Human Behavior &

Evolution Society

Program for the Eighth Annual Meeting of the

Human Behavior and Evolution Society

NOTE:  This was scanned from a printed program.  There are scanning errors in some of the following abstracts.

Welcome to HBES ‘96

Welcome to Northwestern University. Most activities will take place in two general areas. Lodging and meals are in Foster Walker Dorm, and the academic portion of the conference is at Norris Center, Northwestern’s student union. A map of campus is included in this program.

Your local hosts are Bill Irons and Jack Beckstrom. For most issues related to conference logistics, you should find Bill Irons. The program committee consisted of Linda Mealey and Mike Bailey, with input from Bill and Jack.

Nigbtlife. At least three decent bars are near campus. They are: MyBar (most subdued), near Clark and Sherman, Tommy Nevins, on Sherman south of Grove, and the Keg (loudest), on Grove near Sherman.

HBES Officers:

Richard D. Alexander President

Kevin McDonald Secretary/Archivist

Napolean A. Chagnon Past President

Patrick McKim Treasurer

Margo Wilson President Elect

Joanna Scheib

Student Representative

Randolph Nesse Chair Publications Committee

Michael McGuire

Editor-in-Chief

Ethology and Sociobiology

Elizabeth Hill Newsletter Editor

Martin Daly

Associate Editor

Ethology and Sociobiology

Executive Council:

David Buss

Sarah Blaffer Hrdy

Monique IBorgerhoff Mulder

Lee Cronk

William Irons

Jane Lancaster

A Study of Darwinian Aesthetics: Health and Preferences

Tamara Addison

Department of Psychology, McMaster University, Hamilton, Ontario L8S 4K1

g9017681@mcmaster.ca

When a person reacts to a particular scene his or her judgments are a reflection not merely of the features of the stimulus but also how the stimulus is interpreted. People seem to like scenes of places which offer interesting and productive possibilities. Images of natural landscapes and vegetation containing cues of healthy plants are expected to be preferred over ones with unhealthy plants. In a computerized photo­questionnaire experiment, images of plants were manipulated electronically to create variants of the images with only cues of healthiness altered. Healthiness cues included leaf discoloration and damage (holes). In addition, the presence or absence of an insect offered alternative interpretations for the state of the leaves. People rated, on a 7­point Likert scale, the healthiness of the plants and how much they liked the scene. Healthiness and preference judgments were significantly higher for 'healthy' leaves. People prefer looking at healthy plants.

A New Aesthetics

Nancy E. Aiken

P.O. Box 27

Guysville, Ohio 45735

614­662­5701

If art is looked at as a species­specific behavior that has evolved for adaptive purposes, a new aesthetic is needed. A new aesthetic is needed, anyway, because the old aesthetic has fundamental problems in logic, in being exclusive (not all art is included) and, because of its exclusiveness, its ties to artistic traditions of the West. Other contemporary opponents of the old aesthetics (postmodern deconstructionists), because they offer only a reaction to the old aesthetics, also are rebutted. This new aesthetics observes aesthetic behavior and finds: aesthetic behavior includes art making and art appreciating, art can be simple (self­adornment) or complex (the Taj Mahal), all normal human beings are art makers and art appreciators, all human populations through time and geography have produced art. This new aesthetic looks for adaptive purpose in art and finds that ultimately art binds human society together. The new aesthetics asks questions such as: how does art bind societies together, what is the effect of culture on aesthetic behavior, what are the political aspects of aesthetic behavior, what new criticism will result from the new aesthetics. The new aesthetics does not ask what art ought to be (which is what the old aesthetics asks), but what art is.

From Adaptation To Illness: The Case Of Depression

Nicholas B. Allen, Ph.D.

Oregon Research Institute

1715 Franklin Boulevard

Eugene, OR 97403­1983

Evolutionary analyses of depression have often been compromised by a lack of precision concerning which forms of depression were selected for their adaptive utility, and which forms represent pathologies based on adaptive mechanisms. In order to establish a strong argument for the adaptive nature of a putatively evolved mechanism one must specify the "fit" of the mechanism to its environment of evolutionary adaptation, i.e., the mechanism must demonstrate a complex and specific adaptive fit to this environment. Based on these principles, this paper will argue that depressed mood, but not clinical form of depression, satisfy such criteria for an adaptive mechanism. Furthermore, it will be argues that the environment to which human depressed mood is adapted is a specifically social one. Based on these principles a number of logical possibilities regarding the emergence of clinically depressed states will be described. They are (1) poor fit between the adaptive mechanism of depressed mood and the environment, (2) abnormal threshold of activation of one or more of the psychobiological mechanisms that form the substratum the depressive response, and (3) functional breakdown of these psychobiological mechanisms. Empirical research on the cognitive psychology, epidemiology, phenomenology, and actiology of depression will be used to support and illustrate these arguments.

"A Sociobiological Deconstruction of the "Good Husband/Bad

Husband Motif in Dene Oral Narratives"

Wayne E. Allen

The Dene Athapaskans of Subarctic Candada have, until quite recently, maintained an enormous body of traditional oral narratives that are recounted by the elders in their indigenous language. The explicit purpose of these orally­transmitted narratives has been to teach males and females, both young and old, what it is to be "capable" in the traditional bush­oriented lifeway. Implicit in these narratives, though, are themes and motifs ­ e.g., violent male­male competition, male sexual jealousy, parental investment and parent­offspring conflict, sibling rivalries, status striving and dominance hierarchies, selective female infanticide, and mate selection criteria to name but a few ­ that are amenable to a sociobiological deconstruction and analysis.

One genre of these narratives has to do with a group marriage theme, where there are two husbands, a "good" one and a "bad" one, who end up competing with each other for the two wives they share. This situation always precipitates an episode of male sexual jealousy on the part of the "bad" husband, who initiates the male­male competition over the two females wherein he tries to kill the "good" husband. These narratives always end in the death of the "bad" husband by the hand or actions of the "good" husband. In this way an untenable group marriage becomes a tenable polygynous marriage.

Two of these narratives, accompanied by complete illustrations provided by a Dene informant, will be presented with a brief analysis and discussion to follow.

Determinants of parental expenditures among Albuquerque men.

Kermyt G. Anderson, Hillard S. Kaplan and Jane B. Lancaster

Dept. of Anthropology, Univ. of New Mexico, Albuquerque, NM 87131

We measured the financial expenditures of 385 men on the 1093 children they had parented, and tested two models to explain the observations. The Capital model, based on the capital labor market theory (Kaplan et al. 1995), predicts that, controlling for income, parents with more embodied capital will expend more on their offspring. As predicted, the father's embodied capital was a significant predictor of parental expenditures for offspring younger than 24, and was strongest for children ages 18­23; parental embodied capital had no effect for offspring age 24 and older. The second model, the Livebio model, examined the interaction between the child's residency pattern and relationship to the informant. The success of the model varied with the child's age. For children age 18 and over, step­children living elsewhere received less financial investment than other children; however, the data did not support the prediction that men spent more on genetic children living with them than on all other offspring. For children under age 18, no relationship was found between the child's residency pattern or biological relationship and the amount the informant spent on the child. These somewhat surprising results may result from financial expenditures measuring only one aspect of parental investment.

Sexual Orientation, Masculinity­Femininity, and Mating Psychology

J. Michael Bailey, Department of Psychology, Northwestern University, Evanston, IL 60208­2710

On average and in some respects, homosexual people are somewhat similar to the opposite sex. In other respects, they are identical to same­sex heterosexual people. I present results from a program of research aiming to delineate the ways in which gay men and/or lesbians are masculine or feminine. Studies have examined both homosexual and heterosexual, and transsexual individuals. Results have implications for theories of sexual differentiation, the modularity of sex­differentiated adaptations, and the explanations of specific sex­differentiated adaptations.

Individual Differences in Sexually Dimorphic Traits

J. Michael Bailey, Department of Psychology, Northwestern University

Evanston, IL 60208­2710

Evolutionary psychologists have focused their attention on explanations of sex differences. Existing explanations imply tha thte sexes should be entirely distinct on relevant traits. In fact, however, relevant traits show considerable overlap between the sexes, and some of the within­sex variation is heritable. I present examples from both American samples and the Australian Twin Registry.

Should Societies Practice Eugenics with Respect to Reproduction?

Professor Carl Jay Bajema, Biology Department, Grand Valley State University, Allendale, Michigan 49401

The numerous socioeconomic changes taking place in human societies have an effect on the direction and the intensity of natural selection with respect to the reproductive success of genes affecting human mental and physical health. The philosopher Philip Kitcher discusses the inescapability of eugenics in his new book The Lives to Come: The Genetic Revolution and Human Possibilities. Kitcher asks the crucial question "Are we morally committed to courses of action that will utterly debase the lives of our descendants?" Unfortunately Kitcher neglects a very rich intellectual humanist tradition of scientific and ethical discussion of the genetic/cultural implications of social policies. How have the biologist Garrett Hardin (Nature and Man's Fate, "Tragedy of the Commons") and the theologian Joseph Fletcher (Situation Ethics) addressed the issues of population quantity/quality?

Secular Changes in Standards of Bodily Attractiveness in Women: Tests of Evolutionary Predictions

Nigel Barber

Department of Psychology, Box 549037

Birmingham­Southern College, Arkadelphia Road

Birmingham, AL 35254

Women vary in the relative emphasis which is placed on work and marriage as economic strategies. Since success at work is likely to be favored by a more slender body build while success in marriage is favored by curvaceousness, changing standards of bodily attractiveness for women should be predictable from economic and reproductive variables. This hypothesis was tested using published data on bodily curvaceousness in Vogue models. Results tended to support the hypothesis. Curvaceousness is reduced as the economy expands, and as women participate more in the work force and in higher education and reproduce at a lower rate. Results (which replicate and extend similar findings in the sociological literature) suggest that fashions of bodily attractiveness are influenced by an evolved psychology of mate selection.

Against The Ghettoization Of Sociology

Jerome H. Barkow Department of

Sociology and Social Anthropology Dalhousie University Halifax, N.S.

CANADA B3H 3J5

One would expect sociologists to be fascinated with the evolutionary perspective because the latter has yielded so much insight into some of their favorite topics, including crime (particularly homicide, rape, and sociopathy), social stratification and hierarchy, gender and sex, and social exchange. Uninterest in and even antipathy towards the evolutionary approach apparently stems from the Durkheimian insistence that sociology must not be clearly linked to biology or psychology, the historic use of biology and evolution to justify social iniquity and inequity, species chauvinism, tension between sociological feminism and modern science, the scant familiarity of many sociologists with elementary Darwin, and the rise of a strongly anti­ positivistic "postmodern" school strongly influenced by literary criticism rather than by empirical science. These factors are much weaker in the other social sciences, which have correspondingly been much more ready to think from an evolutionary perspective. HBES members can work to influence sociologists and student sociologists by: contacting the authors of sociology textbooks directly in order to acquaint these influential individuals with relevant research and theory; publishing in journals read by sociologists; and by discussing these issues in undergraduate courses sociology students often take. The goal would be to end the increasing ghettoization of sociology.

Sexual Selection as a Causal Factor of Gender Differences in Self­esteem

Alicia Barr, Stephanie L. Brown, Emily Brannon & Angela D. Bryan

Arizona State University

Sexual selection may have favored females and males whose self­esteem was based on self­appraisals of reproductive fitness. If self­esteem measures can serve as a proxy for perceived reproductive fitness, then it is possible that gender differences in self­esteem reflect gender differences in perceived mate value. In particular, resource acquisition should be more important to male self­esteem and physical attractiveness should be more important to female self­esteem. To test this hypothesis, one­hundred and sixty­two male and female students at Arizona State University responded to a personality inventory which assessed self­esteem as well as other dimensions of the self­concept. Specifically, subjects responded to questions concerning physical attractiveness, ability to garner resources, mating potential, social competence, relationship attachments and athletic ability. Subjects' Rosenberg self­esteem scores were regressed on each of the above dimensions. As predicted, a three­way interaction between gender, physical attractiveness and resource potential indicated that a male's self­esteem score was more strongly correlated with his resource potential than his physical attractiveness, whereas a female's self­esteem score was more strongly correlated with her physical attractiveness than her resource potential. Results are discussed in terms of causal factors associated with self­esteem.

Psychological Trauma and Social Polarization

John O. Beahrs, M.E. (116A­OPC)

Portland D.V.A. Medical Center, P.O. Box 1036, Portland, OR 97207

and Department of Psychiatry, Oregon Health Sciences University

Psychological trauma leads to persisting cognitive, affective, and interpersonal sequelae: cognitively, one is more likely to perceive polar extremes within what are better viewed as continua; affectively, avoidance occurs in tension with a quasi­addictive drive to reenact the trauma; and interpersonally, trauma heightens and rigidifies humans' penchant for dichotomizing significant others into allies and enemies. With today's forensic psychiatry "adult delayed recall" controversy a clear case in point, traumatized individuals tend to unite into tightly knit in­groups, like cults; while others are denigrated and defined as enemies. This often creates new enmities where objective interests had formerly clashed only minimally. Traumatic social polarization is hypothesized to be adaptive in dangerous but stable environments where alliances and enmities are likely to persist for decades or more., In rapidly changing environments, the process becomes increasingly dysfunctional; and currently, is a major obstacle to cooperative social problem­solving. Discussion will focus on the risks and benefits of different strategies ­­ clinical, legal, social, and political ­­ for attemting to master this obstacle.

Depression as an Evolutionary Strategy

Aaron T. Beck, M.D.

Department of Psychiatry

University of Pensylvania

Philadelphia, PA 19104­2648

In depression, the patient perceives radically diminished resources (loss of close relationship, shrinkage of financial resources), decreased social influence (due to loss of social attractiveness), and diminished internal assets (due to illness, etc. With the reduction of resources, the value of social influence and internal attributes to self as well as others drops to zero. The catastrophic drop in self­esteem ("worthless, useless") triggers a program involving an overwhelming sense of fatigue and loss of motivation.

The picture in mania is the mirror opposite; the patient perceives an intensification and expansion in her sphere of influence and personal attributes: superior, highly worthwhile, and excessive energy and motivation. The alternation between depression and mania may be viewed as atavistic strategies designed to adapt to the perceived shrinkage or expansion of available resources. Both clinical and ethological evidence support the notion that following defeat or deprivation, the individual slows down, apparently "gives up." I propose that the function of depression in the ancestral environment was to conserve energy and resources whereas mania served to expand resources. The merits and the shortcomings of the formulation will be discussed.

Patterns of Attachment, Mating and Parenting: An Evolutionary Interpretation

Jay Belsky

Human Development and Family Studies

Penn State University

University Park, PA 16802

A modern evolutionary perspective is brought to bear on the three core patterns of attachment­­insecure­avoidant, secure and insecure­resistant­­after reviewing some basic tenets of life­history theory which emphasize the role of environmental influences on reproduction. Mating and parenting correlates of secure/autonomous, avoidant/dismissing and resistant/preoccupied attachment patterns are reviewed and the argument is advanced that security evolved to promote mutually­beneficial interpersonal relations and high investment parenting; that avodiant/dismissing attachment evolved to promote opportunistic and disproportionately self­serving interpersonal relations and low investment parenting; and that resistant/preoccupied attachment evolved to foster "helper­at­the­next" behavior and indirect reproduction. The role of constitutional temperament and plasticity in development are also considered in this facultative analysis of early and enduring attachment patterns.

Mate preferences: Implications for gender differences in depression and body dissatisfaction

Souhir Ben Hamida

Northwestern University

We combine two models to investigate gender differences in depression. The reformulated learned helplessness theory (Abramson, Seligman, & Teasdale, 1978) outlines the mechanisms by which uncontrollability can lead to dysphoria. We use mate preferences theory (Buss, 1989) to argue that characteristics that increase women's mate value (youth, attractiveness) are more immutable than traits that increase men's desirability (status, industriousness). Women's reduced control over desirable attributes may increase their risk for helplessness, dysphoria, and low self­esteem. We conducted two studies to test this hypothesis, one using 150 undergraduates, another using 301 older adults. Subjects rated the importance of various traits when selecting partners, and their degree of perceived personal control over the same traits. Men's controllability ratings were higher on traits that women rated as more important in mate selection, compared to women's controllability ratings on traits that men rated as more important in partner selection (college and older sample: e.s.=1.75; e.s.=1.03). Generalized gender differences in perceived controllability could not account for these findings. Traits on which women are selected appear to be more uncontrollable than those on which men are selected, suggesting one reason that women are at higher risk for depression and body dissatisfaction.

Exploring The Labyrinth From Dominance To Paternity In Primates

Fred B. Bercovitch

Caribbean Primate Research Center

One of the most consistent findings to emerge from the primate literature is the inconsistent relationship between rank and reproduction among males. Variables that can affect the chances of high ranking males mating more than low ranking males include the number of females in a group, the degree of cycle synchrony, the length of the mating season or sexually receptive period, the number of males in a group, the extent to which males can adopt alternative reproductive tactics, physical features of the environment, morphological attributes, and patterns of mate choice. Comparing behavioral assessments of paternity with actual paternity has provided insights into the actual payoffs of different male reproductive strategies, but the use of genetic data has revealed the same inconsistent link between male rank and reproduction. The relationship between dominance and reproduction in male primates is a conditional probability, not a predictable correlation.

Address all correspondence to:

Fred B. Bercovitch

Caribbean Primate Research Center

P. O. Box 1053

Sabana Seca, PR 00952

(809) 784­6619; FAX: (809) 795­6700

Father Absence and Mate Preference: Do Birds of a Feather Mate Together?

Gerald Beroldi

Department of Psychology, Simon Fraser University

Burnaby, BC; Canada V5A 1S6

email: gerald_beroldi@sfu.ca

This poster is on two works in progress. One is a review of the evolutionary and non­evolutionary literature self­identified as father­absent. The theory upon which the evolutionary literature is based is within the Darwinian anthropology tradition. These works are from an evolutionary psychology perspective with an attempt to elucidate and test the psychological mechanism mediating the effect that father absence and presence has on the mating strategy of their off­spring. This review is planned to be the core of a broader review of the literature concerning the putative developmentally contingent effects of one's father presence in, or absence from, one's home during a critical period (age 0­5 or 0­7). This larger review in turn will be the basis for a study investigating a replication of these effects. The other work is a questionnaire that was developed to test the hypothesis mentioned by Harpending & Draper (1983) and Blain (1984) that individuals from father absent or present homes tend to choose mates from the same type of home. This questionnaire is for females, a future one will be for males.

Delayed Reciprocity And Tolerated Theft: The Behavioral Ecology Of Food Sharing Strategies

Rebecca L. Bliege Bird

Department of Anthropology

University of California, Davis 95616

Models derived from behavioral ecology may have the potential to explain a great deal of variability in food sharing patterns within and between human societies. I use quantitative observational data on the hunting and sharing of large animal prey (marine turtle) among the Meriam of the Torres Strait to test specific predictions of reciprocity­based and tolerated theft sharing models, evaluating the extent to which such models can account for the way in which prey are distributed after acquisition. I also evaluate the influence on sharing strategies of seasonal variability in the costs and benefits of pursuing prey. Prey are shared widely and unconditionally when costly to acquire, and more narrowly when acquisition costs are low. Hunters receive little consumption benefit when prey are shared widely, and only receive high consumption benefits when they hunt for their own household's consumption. I conclude that hunters seek both social and consumption benefits from prey and that these goals can be predicted according to seasonal variability in the costs of acquisition and the reproductive strategies of individual hunters.

The Group Mind: Groups As Complex Adaptive Systems

Howard Bloom and Michael Waller

National Coalition of Independent Scholars

howlbloom@aol.com

mwaller@comparator.win­uk.net

David Sloan Wilson has asked: "Can social groups evolve into functionally integrated units, similar to single organisms in their adaptive design?" This paper will argue that the answer is yes: social organisms often coalesce into what might be termed a group mind. John Hopfield's neural nets and J.H. Holland's Classifier Systems model the manner in which individual components combine to make each solo element a module in a learning machine. It will be argued that a complex of autonomic biological devices similarly orchestrate social individuals to function like components of a group brain. A range of studies will be cited indicating that these physiological systems, which we call comparator mechanisms, either shut down or invigorate the individual depending on its likely contribution to mastery of communal challenges. Examples will be drawn from honeybee colonies, bird swarms, lower primate bands, and human groups of all sizes. Intergroup competition and environmental change frequently place a high premium on the rapid generation of new, adaptive responses. Hence the ubiquity of genetic coalitions which energize or handicap their carriers to maximize their function as constituents of a collaborative intelligence.(186 words)

Five Mechanical Routes To Altruism

Chris Boehm

Department of Anthropology, University of Southern California

fax: 213­747­8571

Evolutionary biologists have relied exclusively upon inclusive fitness/reciprocal altruism arguments to explain altruistic behavior because group effects are so weak that they are inevitably swamped by individual (inclusive) effects. It is proposed, for humans, that five factors have made possible substantial augmentation of group effects at the expense of individual effects. The first four are cultural. Egalitarian leveling behavior and group consensus seeking reduce intra­group phenotypic variation among individuals, while group decisions and emergency decisions in particular amplify phenotypic variation among groups. In addition moral sanctioning of free­loaders and cheaters provides special reproductive advantages to altruists. There is also a genetic factor. Pleiotropic traits that are well­supported by inclusive fitness may be inextricably coupled with altruistic traits that are moderately costly, and therefore can be maintained in spite of their costs. By taking these five factors into account, a selection scenario can be created in which many types of (non­kin) altruism are readily explained. The realigned balance of power between individual and group levels of selection helps to explain strong ambivalences found in human nature.(180 words)

Status Reinforcement Behavior, Long Term Fitness, And The Evolution Of Conspicuous Consumption

James L. Boone and Karen Kessler

Human Evolutionary Ecology Program, Anthropology Dept., University of New Mexico

Albuquerque, NM 87131

e­mail: jboone@unm.edu

Most analyses of the correlation of socioeconomic status with reproductive success have treated wealth and status as a condition or outcome, focusing on the proximate benefits of socioeconomic status­­increased access to mates and higher fertility­­rather than treating status reinforcement as an ongoing social strategy which itself involves both costs and benefits. In many ranked and stratified societies considerable resources are invested purely in status reinforcement-resources that could have gone into further production of offspring. Why? We argue that the utility of status is not limited to the momentary benefits of greater access to resources. Rather, status reinforcement has evolved as a behavioral strategy that increases probability of survival through relatively infrequent, but recurrent demographic bottlenecks by determining individual/ familial priority of access to of resources accumulated, produced or defended collectively by the social group during periodic shortages. Maintaining priority of access requires expenditures in the form of defense costs and costly signalling, often in the form of conspicuous consumption. In many contexts such expenditures may divert resources away from further production of offspring, yet these short term costs are offset by the long term benefits of increased survivorship through recurrent crashes.

Evolutionary Analysis of Suicidal Ideation and Behavior

R. Michael Brown and Kirsten Melver

Department of Psychology

Pacific Lutheran University

Contemporary explanations of suicide view it as a pathological response to depression and hopelessness. The idea that at least some aspects of self­destructive motivation may be part of our evolutionary heritage has received little attention in spite of the exposition of a formal mathematical model outlining possible adaptive functions of suicide. In a recent study, we reported findings consistent with this model. We designed the present study to provide a more finely tuned analysis of fitness variables that appear related to components of suicide, and to determine how they might be related to another component of self­destructive motivation­­psychological pain. University students served as subjects, and variables were constructed from a questionnaire. Results indicated that psychological pain was highest among those individuals who considered themselves a burden to their kin, were low in reproductive potential, and had kin who were low in reproductive potential. Psychological pain accounted for more of the variance in suicidal ideation and behavior than did any of our other predictors. Taken together, our findings raise the possibility that suicidal ideation and behavior result from failed attempts to reduce psychological pain.

An Empirical Examination of the Evolutionary Mechanisms of Prosocial Behavior

Stephanie L. Brown, Brian P. Lewis, Robert B. Cialdini, Steven L. Neuberg, &

Carol Luce.

Department of Psychology, Arizona State University, Tempe, AZ 85287

Theories of reciprocal altruism and inclusive fitness posit that selection pressures have favored the existance of prosocial behavior. Since indiscriminate helping can be maladaptive, it is probable that helping another is predicated upon the perception that helping will enhance the giver's inclusive fitness either by benefiting kin or by engendering future help. One indicator of the extent to which helping serves this purpose may be the helper's perception that the recipient and the helper share a 'sense of self', either through kinship or intimacy. In order to test this prediction, 242 undergraduates were presented with a helping scenario that varied in the severity of the situation, and in the closeness of the target­­a stranger, aquaintance, close friend, or sibling. Participants were asked to report how much help they were willing to give the target, their emotional response to the person in need, and indicated the extent to which the target's identity overlapped with their own. Results indicate that as this overlap increased, so did the amount of help given. Additionally, as the helping situation became more severe, the difference in help as a function of perceived overlap became more pronounced. Structural equation modelling confirmed these results and demonstrated that emotional feelings toward the target had only an indirect effect on helping, mediated by the perception of self­target overlap.

The Glass Ceiling, the Gender Gap, and Evolutionary Biology

Kingsley R. Browne

Wayne State University Law School

Detroit, Michigan 48202

The "glass ceiling" and the "gender gap" in compensation are commonly viewed as indicia of unfairness to women and attributed to inappropriate employer behavior and sexist socialization patterns. However, well­known stereotypes of men as more competitive, more driven toward acquisition of status and resources, and more inclined to take risks than women, and stereotypes of women as more nurturant, more risk averse, less greedy, and less single­minded than men are true as generalizations. These temperamental sex differences have an underlying biological basis that appears to be a legacy of our evolutionary history.

These sex differences are responsible for much of the sex difference in workplace outcomes. Characteristics of successful executives - both male and female - include the "male" traits of aggressiveness, ambition and drive, a "passion for success," and a willingness to take risks. Factors that explain differences in overall compensation for men and women include number of hours worked, riskiness of job (both in terms of physical risk and "career risk"), amount of job­related schooling, and pleasantness of surroundings.

From Vigilance to Violence: Mate Retention Tactics in Married Couples

David M. Buss and Todd Shackelford

Department of Psychology, University of Michigan, Ann Arbor MI 48109­1109

Although much research has explored the adaptive problems of mate selection and mate attraction, little research has been conducted on the adaptive problem of mate retention, despite the fact that more than 50% of all married couples in the United States end up divorced. This study was designed to test seven evolutionary psychological hypotheses about the determinants of mate retention in a sample of married individuals (N = 214). We assessed the usage of 19 mate retention tactics, ranging from vigilance to violence. Empirical support was found for the hypotheses that men's, but not women's, mate retention effort is a function of the partner's youth and physical attractiveness, even after statistically controlling for the man's age and the length of the couple's relationship. Women's mate retention, although less predictable than that of men, was correlated with the effort allocated by their husbands to the problem of hierarchy negotiation. Overall, men reported using higher frequencies of resource display, vigilance, and intrasexual threats to retain their mates. Women reported using higher frequencies of appearance enhancement, emotional manipulation, jealousy induction, and derogation of competitors. Discussion focuses on the evolutionary psychology of mate retention and the importance of this psychology for understanding spousal violence.

Sex Differences in Partner Preferences: A Replication and Extension in The Netherlands

Bram P. Buunk, Astrid Warntjes & Douglas T. Kenrick

University of Groningen, The Netherlands

The present study among 137 subjects examined sex differences in partner preferences in The Netherlands. Subjects were either 20, 30, 40, 50 or 60 years of age. In line with predictions based upon evolutionary theory the results showed that females, regardless of their age, preferred partners a few years younger or a few years older than themselves. In contrast, among males the discrepancy between one's own age and the preferred age of a potential partner was larger as males were older. For instance, males of 60 years old preferred females with a minimum age of 35, and a maximum age of 53. Females found a high income, a high level of education, dominance, intelligence and social status of a partner more important than males, whereas males found physical attractiveness more important. The higher the level of involvement with a potential partner (sexual fantasy, short­term sexual affair, fall in love, steady relationship, marry), the higher the preferred educational level, dominance, and physical attractiveness of the partner. Males and females required the highest level of physical attractiveness for a partner about whom they would have sexual fantasies. Some evidence was found that males had lower standards than females for short­term sexual affairs.

What Should Evolutionary Critics Do?

Joseph Carroll

English Department, UM­­St. Louis

The effort to study literature from an evolutionary standpoint has only just begun, and there is no consensus among the practitioners as to precisely what it is they can and should be doing. Many Darwinists harbor understandable doubts as to whether (as John Constable puts it) "biologized criticism" can be "an integrated part of human behavioral science." Among those who have attempted any such integration, the most common form of practice so far has been to examine literary texts with the intent of extracting examples of behavior that illustrate principles of evolutionary psychology, especially reproductive psychology. I shall argue that "criticism"­­the analytic, interpretive study of individual texts and groups of texts­­is a necessary precondition for any literary study likely to produce substantive findings of some value and interest to human behavioral science. I shall argue also that combing literary texts for behavior that illustrates evolutionary psychology is at best a rudimentary form of analysis. A more fruitful method would be, first, to use evolutionary psychology to establish a common analytic framework for understanding meaning in literary texts, and second, for specific texts, to examine the way proximate motives interact with complex cultural situations to produce representations that are often far removed from simple illustrations of fitness maximization.

Variation in Female Competition

Elizabeth Cashdan

University of Utah

Reproductive trade­offs and differences in access to resources favor differences in reproductive strategies among women. These differences affect the ways in which women compete with each other.

This study, which uses competition diaries, indicates that women are more competitive with other women over men when either (a) the women come from poor families, or (b) they are sexually unrestricted (willing to engage in sex with less evidence of long­term commitment

from a man). These findings are consistent with literature reports showing aggressive competition among women for the attention of desirable males in communities characterized by low paternity

confidence and economic scarcity. Competition among women over mates may be more acute in such communities both because of limited economic resources and because the presence of sexually unrestricted women poses a greater threat to a woman intent on keeping her mate.

As women become older and less fertile, their mate value should decline. We might expect, therefore, that they will become less sexually restricted as they become older. This expectation is

supported both by literature accounts of female­female aggression and by this data set. A woman's competitive strategies may be expected to shift accordingly as she ages.

Are Group Minds Self­Organizing Systems?

Hiram Caton

Griffith University, Brisbane, Australia

h.caton.hum.gu.edu.au

Recent applications of nonlinear mathematics to the description of animal aggregations (Kauffman) and to game theory (Nowak & Sigmund) suggest that self­organisation may be the 'missing link' in neo­Darwinian orthodoxy. After mentioning some trouble spots in neo­Darwinism (saltationism in the fossil record), the paper notes the forgotten tradition of group selection in evolutionary biology (Allee), and current work on group selection (D S Wilson, Boyd & Richerson). Although the group mind(s) is widely regarded as a discredited concept, its use under other names is pandemic in the social and evolutionary sciences. The central theoretical blockage is the apparent absence of a theory able to treat individual events as both individual and as aggregates in non­reversible real time. Nonlinear mathematics provides many avenues of approach. The central empirical blockage is the apparent absence of measures of 'groupness' of group behavior. There are many such measures; the paper attends especially to ethological description of behavior synchrony. I conclude with a clarification about just what is attributed when an aggregate is said to be of a common mind. I argue that the attribution involves a necessary cognitive illusion, similar perceptual illusions. Its evolutionary origin is Homo sapiens' facultative eusociality. Its social effect is to mobilize the appearance of an authoritative or unchallengeable consensus, which in turn gives effect to sudden and dramatic group action on small and grand scales.(229 words)

Attachment And Time Preference: Algorithms For The Contingent Development Of Reproductive Strategies

James S. Chisholm

Department of Anatomy and Human Biology

University of Western Australia

Nedlands, WA 6907

Australia

This paper investigates hypotheses drawn from two sources: (1) Belsky, Steinberg and Draper's (1991) attachment theory model of the development of reproductive strategies, and (2) recent life history models and comparative data that suggest that environmental risk and uncertainty may be potent determinants of the optimal tradeoff between current and future reproduction. A retrospective, self­report study of 136 university women aged 19­25 showed that current recollections of early stress (environmental risk and uncertainty) were significantly related to individual differences in adult time preference and adult sexual behavior and attitudes, and that individual differences in time preference were significantly related to adult attachment organization and sexual behavior. These results are consistent with the view that perceptions of early stress index environmental risk and uncertainty and mediate the attachment process and the development of reproductive strategies. In this view individual differences in time preference are considered to be part of the attachment theoretical construct of internal working model, which itself is conceived as an evolved algorithm for the contingent development of alternative reproductive strategies.

KEY WORDS: Life history theory; Attachment theory; Reproductive strategies;

Early stress; Environmental risk and uncertainty; Sexual behavior of young

women.

Sex Differences in Spatial Mapping Strategies

Jean Choi and Irwin Silverman

York University, 4700 Keele St., Toronto, Ontario, M3J 1P3

Recent studies with humans have revealed sex differences in preferred strategies for route learning, with males disposed to Euclidean methods (the use of distance concepts and cardinal directions) and females to topographical techniques (the use of landmarks and relative directions). The present study was designed to assess whether these differences represented a default strategy on the part of females, compensating for their lesser general spatial abilities, or an evolved dimorphism. The latter view was based on the historical role of females as caretakers of the habitat and foragers for food, both of which would have required superior incidental recall of the location of objects. The evolved dimorphism theory was favored, particularly by data showing that route learning success was related to Euclidean strategy preferences for males only and topographical strategy preferences for females only. An attempt to establish whether strategy preferences were related to estrogen level yielded ambiguous findings.

Mate Choice And Kin: "Gosh, Your Cousin Is Ugly!"

Melissa L. Citro and Jack Demarest

Monmouth University, Department of Psychology

West Long Branch, NJ 07764

Research on mate choice has focused on characteristics of potential mates. Inclusive fitness theory suggests that the traits of close kin may also affect mate preferences. Using written scenarios, two studies examined how likely men and women would get involved with a person whose kin exhibited one of 8 traits (attractiveness, youthfulness, leadership, success, wealth, faithfulness, nurturing or family oriented, faithfulness, infertility, or a genetic disorder leading to death). This choice was compared to a potential mate whose relatives did not have the trait. Kinship was either close (r = 0.5) or distant (r < 0.26) and the level of commitment to the relationship varied (one date, sexual intimacy, serious dating, or marriage). Results show that males were less selective than females concerning sexual intimacy, but more selective when it came to marriage. Men preferred a mate with attractive kin; women preferred a mate with financially successful kin. Those with kin who had a genetic defect (infertility or a fatal disorder) were highly unlikely to be selected as mates.

Jealousy: Adaptive or Destructive?

Heather Claypool and Virgil Sheets

Department of Psychology

Indiana State University

Terre Haute, IN 47809

Evolutionary theorists argue that jealousy is an adaptive psychological mechanism that promotes mate retention and thus relationship stability. Social psychologists, in contrast, contend that jealousy is an unsettling force that promotes relationship dissolution. To test these contrary predictions, college students involved in a romantic relationship were surveyed regarding jealousy in the fall, and recontacted in the spring to assess the status of the relationship. Cross­sectional analyses showed that the respondents' jealousy was negatively correlated with expected relationship stability, but their partners' reassurance was positively correlated with expected relationship stability. Prospective analyses showed no effect of respondents' jealousy on actual relationship stability, but positive effects of partners' reassurances and of partners' jealousy. These results seem more consistent with adaptive than destructive models of sexual jealousy.

Is the Influence of Single­Parent Families on Children Qualitatively

Different? A Behavior Genetics Analysis of the National Longitudinal

Study of Youth

Hobart H. Cleveland III and Richard P. Wiebe

Department of Family Studies

Department of Psychology

University of Arizona, Tucson, Arizona

Some investigators (e.g. Draper & Harpending, Belsky) have proposed that certain family structures, such as single parenthood, can trigger conditional life strategies in children developing thereunder. These, we believe, would be evinced by qualitatively different predictors of child outcomes in these families when compared with two­parent families. An alternate hypothesis holds that factors influencing development, including but not limited to the biological relatedness between the child and the caretakers and the amount of attention and monitoring afforded the children, influence children similarly regardless of family structure. These hypotheses were tested through examining genetic and environmental influences on intellectual abilities and behavior problems in whole and half siblings born to original participants in the National Longitudinal Study of Youth (NLSY), a national probability sample of over 11,000 respondents born between 1957 and 1964. Patterns of covariance were compared to determine whether a single multivariate model fit both single­ and two­parent families, or whether different models were needed.

The Biology And Culture Of Moral Systems

Kathryn Coe

Hispanic Research Center, Arizona State University

e­mail: icmck@ASUVM.INRE.ASU.EDU

In this paper I will examine existing data in light of Alexander's proposition that humans have one system of behavior codes and that that system is aimed at leveling reproductive opportunities. I will examine the earliest system of rules of behavior based on evidence found in modern hunter­ gatherers, as well as the system found in the early state. Attention is paid to the source of the system and the justification for it, the codes themselves, the presence or absence of an authoritative hierarchy that has the ability to use force or coercion, the boundary of the system, and the methods used to determine guilt, punish offenders, resolve conflicts, educate youth, and enact legislation.

It is argued that both kinship­based and state­based systems of behavior codes are based on religion; that is, they are based on the communicated acceptance of non­verifiable claims. An example of one such claim would be that the rules are of divine inspiration and that breaking them will bring about divine retribution. The acceptance of these supernatural claims has the significant effect of encouraging cooperation in the moral system.

Evolutionary Applied Psychology and the Workplace

Stephen M. Colarelli, Bradford Kruse, & Matthew J. Such

Department of Psychology

Central Michigan University

This paper examines the relationship between evolutionary principles and applied psychology, and it explores how an evolutionary applied psychology might be useful in the workplace. A principal goal of applied psychology is to use psychological knowledge to achieve intended effects. How might an evolutionary applied psychology be useful, given that evolution implies that change is (usually) slow, context­dependent, and difficult to predict? It would, first, require a different set of assumptions than traditional applied psychology. These would include: (1) the ecological nature of complex systems; (2) the role of variation, selection, and retention as a principal change mechanism in socio­cultural systems; and (3) the existence of content­specific psychological mechanisms that influence behavior. These assumptions suggest different, although perhaps more realistic, approaches for using psychological knowledge. One is the use of evolutionary algorithms and computer simulations to "grow"­­rather than design­­alternative organizational arrangements, based on different sets of inputs and goals. Another evolutionary approach is using variation as an intervention principle. Methods to increase or adjust variation­­and then allowing organizational selection and retention mechanisms work­­may be more useful than designing a priori solutions. A third approach is to use knowledge from evolutionary psychology. For example, given psychological mechanisms related to dominance, status, cooperation, and sexual behavior, an evolutionary applied psychology might suggest interventions that focus on organizational demographics (sex ratios, age distributions), group composition, and propinquity.

"Some Determinants Of Human Capital Achievement For The Children Of Albuquerque Men"

Benjamin Connor, Hillard Kaplan & Jane Lancaster

Dept Of Anthropology, University Of New Mexico

Albuquerque, Nm 87131­1086

Recent theoretical developments combining life history and economic optimality approaches (Kaplan, et.al. 1995) have led to the expectation that the impact of parental time investments on the rate at which a child acquires embodied human capital will be dependent on the parent's own levels of human capital. As a consequence more educated parents are expected to invest more time with their children than less educated parents. For a sample of 620 children of Albuquerque men it was found that paternal time investment, measured as the number of hours per week that the father spent with the child during preschool years, has a significant positive effect on the child's probability of graduating from high school. Maternal time investments, measured by the percent of time that the mother was employed in wage labor during the child's preschool years, has a similar effect. Both father's and mother's education levels also have a significant positive impact on the probability of high school graduation. The educational levels of both parents were expected to interact with their time investments, i.e. the more educated the parent, the greater the impact of their time investment on the child's probability of graduating from high school. Tests of this hypothesis gave mixed results.

The Epidemiology of Cultural Representations: Verse Forms in English Language Poetry

John Constable

Dept. of International Culture, Faculty of Integrated Human Studies, Kyoto University, Sakyo­ku, Kyoto, 606. Japan.

Fax: 075 753 6647. E­mail: john@ic.h.kyoto­u.ac.jp

No study of cultural materials which is predominantly evaluative, or critical, can be sufficiently technical to lead to consensus among researchers, and hence biologized criticism cannot be either an integrated part of human behavioural science, or a satisfying university subject. The theory of culture and cultural studies which offers the most promising alternative to critical interpretative and historical studies is Dan Sperber's program for cultural epidemiology, an approach which has the twin virtues of introducing population thinking into the study of culture, and of taking physicalism seriously. Following Sperber's lead this paper reports on a pilot study examining changes in the frequency of verse forms in English language poetry. The drift of high literary writers from restrictive forms to less restrictive forms, an aspect of verse which is discussed in detail, is explained in terms of the need of these writers to maintain the status of their production in the face of intense competition from an unrestricted form rising to dominance in the cultural pool, prose.

It is proposed that although apparently distant from evolutionary thinking, this mode of cultural study is not only compatible with evolutionarily grounded psychology, but is an extension of the general principles of darwinian theory.

Utopian Fiction and Human Nature

Brett Cooke

Modern & Classical Languages

Texas A&M University

College Station, TX 77843­4238

Utopian fictions provide a heretofore unstudied illustration of Alexander Argyros' dictum that literature is a society's means of choosing its future. Planning ahead would seem to be one of the major advantages of speculative thought, and art outstrips philosophical discourse to these ends by permitting one to vicariously live in an envisioned social order with a greater degree of fulsome experience. It allows us to visit utopia.

The past is highly relevant to such forward­looking inquiry. This is notable by how often the issue of human nature is relevant to utopian discourse, especially to the utopia/dystopia distinction. This study tests the hypothesis that fictional utopias will dictate behaviors similar to those attributed to the EEA. There is little point to social engineering if it does not make one feel better. Artists like More, Chernyshevsky and Bellamy accomplish this by reminding us of ancestral ways of life. On the other hand, there are two corollaries to dys­(or anti­) utopian fictions: these will affront human nature by depicting societies which require behaviors that either 1) affront established patterns or, 2) over­do them. Examples of food sharing, personal identity, social size, sexuality, and religious structures also will be provided from works by Huxley, Orwell and Zamyatin.

What Behavior Genetics Can Tell Us About Evolved Human Psychology

Leda Cosmides and John Tooby

Center for Evolutionary Psychology, CORI

University of California, Santa Barbara 93106

tooby@alishaw.ucsb.edu fax: 805 965­1163 phone: 805 893­8720

The study of the impact of genetic variation on behavior can be an important tool in exploring a range of questions that are central to an evolutionary understanding of humans. Perhaps the most interesting and underutilized application is how behavior genetics may be used to explore human species­typical psychological architecture. In particular, the continuous injection of new mutations and the background presence of genetic noise provide natural diagnostic probes, much like strokes or head trauma are presently used in cognitive neuroscience. Mutations in the genetic specification of complex psychological adaptations are expected to cause impairments that may help reveal the evolved functional architecture of cognitive specializations in normal unimpaired individuals. This emerging cognitive genetics offers alternatives to the study of individuals with ontogenetically caused neural impairments, because physically caused neural damage has no intrinsic tendency to follow functional boundaries, while a subset of mutationally introduced variation may. In contrast, the methods presently available in behavior genetics allow almost no conclusions to be made about the sources of intergroup differences in quantitative behavioral characters, or about how responsive novel or unstudied environmental interventions may be in changing the expressed phenotype along socially targeted dimensions.

WHEN IN ROME...A Small Scale Test Of Boyd and Richerson's Conformist Transmission Model

Julie Coultas

School of Cognitive and Computing Sciences

University of Sussex

U.K.

Some imitative behaviour in humans is spontaneous and is produced through a predisposition to imitate the most common behaviour. This behaviour is more likely to be elicited if an individual is naive and in an uncertain environment. A small scale test of Boyd and Richerson's (1985, 1991) conformist transmission model was undertaken using 105 first year psychology undergraduates (separated into 8 groups) in their first ever computer practical class. A normally, rare behaviour was modelled by a number of (unknowing) stooges. As each subject entered the laboratory the proportion of others modelling the rare behaviour was noted and the behaviour of the newcomer was recorded. Logistic regression indicated that proportion of individuals modelling the rare behaviour was a significant predictor of imitation. Thirty one per cent of subjects imitated the behaviour when the initial group size was five. No subject imitated the behaviour when initial group size was three and no subject imitated the behaviour when the proportion producing the behaviour was less than seventy one per cent. Phenomena such as this are discussed in terms of their contribution to an explanation of human cooperative behaviour.

Heroic Literature as Aggression Control Mechanism:

Theoretical Prolegomena and a Pilot Experiment

Gary Cox

Foreign Languages & Literatures (Russian)

Southern Methodist University, Dallas, Texas 75275

(214) 768­2294, fax: (214) 768­3341, e­mail: gcox@post.smu.edu

It is hypothesized that a group's recorded aggressive fantasies constitute a mechanism for regulating levels of aggression. The recent 4­university study on televised violence distinguishes between aggression­inhibiting motifs and aggression­enhancing ones, giving us a valuable experimental instrument.

Further study requires a theoretical stance on the interface between physiological components (impulses) and cultural components (constructs) of behavioral responses to fantasy aggression. Culturally transmitted data are constructs, but they are constructs of something (construe is a transitive verb); what is construed is an impulse, triggered physiologically or environmentally. Genetically conditioned aggressive impulses may be "domain­specific modules." The phenotype or group construes the impulse in accord with self­defined proximate needs, ignorant of its genetic goal (selective reproductive fitness). Inherited neural structures may be "exploited" by culture in ways divergent from, or opposed to, the selective advantages that stimulated their evolution (e.g., status competition among monks; e.g., mooning). Fantasy ability (i.e., literature) may have evolved, through mimesis, as a device for enhancing "exploitative construction" of hard­wired impulses.

As a pilot experiment, rates of aggression­inhibiting and aggression­enhancing motifs are contrasted in 3 representative bodies of oral and written literature: Yanomamo folklore, Russian folklore, and chivalric romances. Hypothesis tentatively confirmed.

Dominance Hierarchies and The Evolution of Reasoning

Denise Dellarosa Cummins

Cognitive Science

University of Arizona

Tucson, AZ 85721

There is a good deal of evidence from primatology and evolutionary anthropology that the most pressing reasoning problems primates faced during their evolution were of a social nature. The most crucial of these falls under the category of deontic reasoning, that is, reasoning about what is permitted, obligated, or prohibited. As a simple example, avoiding agonistic encounters and ostracism requires reasoning effectively about the permission structure inherent in primate dominance hierarchies (i.e., who may groom, play, and mate with whom). Acquiring and maintaining status within the hierarchies depends on forming and maintaining alliances based on reciprocal obligations. My thesis is that problems like these occurred so frequently and with such adaptively important consequences that domain­specific reasoning modules evolved for solving them. In support of this, I present evidence that, unlike other types of logical reasoning, deontic reasoning emerges early in human development, is dissociable from other types of intelligent reasoning at the neurological level, and is apparent in the reasoning of protocols of adults regardless of culture and educational background.

Three Lessons of Biology for Psychology:

The Adapted Mind, Within­Organism Selection, and Perceptual Control Theory

Gary Cziko

University of Illinois at Urbana­Champaign

Biology provides three important lessons for understanding human behavior. The first is that the human mind is a product of the human brain which is the result of natural selection. The second lesson is the evolution of evolution, i.e., _among_­organism variation and selection has resulted in the evolution of mechanisms of _within_­organism variation and selection, as is the case for the immune system's production of antibodies, brain development, and aspects of cognition. Through within­organism cognitive variation and selection, the adapted mind becomes an adapt_ive_ mind. The third lesson is that organisms have evolved negative­feedback control systems to regulate not only their internal environments ("homeostasis") but also aspects of their external environment, resulting in what we observe as purposeful, functional behavior. While the first of biology's three lessons is well accepted by evolutionary psychologists, the other two are not. Arguments based on both theory and research will be made for the importance of biology's second and third lessons, going beyond the development in my _Without Miracles_ (1995, MIT Press). Also, a computer simulation will be shown demonstrating how the interaction of negative­feedback perceptual control systems accounts for imprinting behavior in birds and human collective behavior.

HOW TO DISTINGUISH EXAPTATIONS FROM ADAPTATIONS IN EVOLUTIONARY PSYCHOLYGY?

Austin Warren Dacey

Bowling Green State University

Evolutionary or Darwinian psychology holds human psychology to be largely a collection of adaptations. Contrary to this, Gould has suggested that human psychology is largely a collection of EXAPTATIONS, or structures currently put to a use other than that which they were selected for. If he is right, then evolutionary psychology would be left with not much to talk about. It contends that many important features of human psychology are best explained by the theory of natural selection. But exaptations cannot be so explained, since their present features are not the product of selection for those features.

This essay addresses not the crucial question of whether the mind is mostly a collection of exaptations or adaptations, but rather the prior question of how to distinguish the two in evolutionary psychological explanantion. I begin by elaborating on the invention and use of the concept 'exaptation' in biology, and introducing several terminological distinctions to improve its application. Second, I indicate two general difficulties with the application of the concept, one of which appears in Gould's analysis. Third, I examine a method of distinguishing exaptations from adaptations­­ recently emphasized by Pinker and Bloom­­ by which one recognizes an exaptation by its deployment of complex and specialized problem­solving machinery in a task that does not require such complexity or specialization. I conclude that because of some interesting complications, this is not a good method for evolutionary psychological explanation. Finally, I point to a method that is more promising.

I suspect that the possibility of exaptation does not mean the cancellation of the research program of Darwinian psychology, but rather its further refinement and progress. I am hopeful that close analysis of the concept of exaptation will be a contribution to that end.

EVOLUTIONARY PSYCHOLOGY OF KINSHIP: A PROMISSORY NOTE

Martin Daly, Catherine Salmon and Margo Wilson

Dept. of Psychology, McMaster University, Hamilton, Ont. L8S 4K1

Daly@McMaster.CA

Kinship is the central construct in evolutionary biological analyses of social phenomena and kinship is also central to anthropological analyses of social phenomena as well. Since kinship is so important both theoretically and phenomenologically, one might suppose that it would have attained a central position in social psychology, too, but alas it has been virtually ignored. What has yet to be appreciated by psychologists and other social scientists who lack a selectionist perspective is that different classes of social relationships are qualitatively distinct in many specific ways rather than just in their degrees of intimacy.

Human kinship systems are dauntingly diverse, but they have many universal aspects. We shall consider 13 putative universals of human kinship psychology which suggest that our species possesses a complex evolved system of kinship cognition adapted to the task of nepotistic decision­making.

An Evolutionary Theory of the Human Family

Jennifer Davis and Martin Daly

Department of Psychology

McMaster University

Hamilton, Ontario

davisjn@mcmaster.ca

Emlen's recent paper "An evolutionary theory of the family" (PNAC, 1995) provides a valuable summary of existing theories about the nature of family systems and the reasons why they have evolved in certain species. Emlen's theoretical account leads him to propose 15 predictions about how family systems function, and he reviews evidence in their favor. Elucidation of the evolved psychological mechanisms that govern human reproductive decisions and consideration of unusual aspects of human sociality may help explain the deviation of available data from the predictions, as they are currently worded, and provide insight into how to better apply them to human family systems.

Parental Investment: "When Mom Can Provide Resources"

Jack Demarest and Megan Schramm

Monmouth University, Department of Psychology

West Long Branch, NJ 07764

We examined differences in perceived levels of parental investment by husbands and wives as a function of the wife's ability to provide resources (occupational status) and the age of their offspring. 46 couples indicated how much time per week each parent spent on various parental investment activities, including time at work outside the home; time devoted to nurturing the child; playing with the child; ensuring child's safety; educating the child; and custodial care. The proportion of income each parent provided was also calculated. As expected, men provided more investment in time at work outside the home, and in financial contributions; women invested more in every other category. Wives who provided the most resources (high occupational status) and who had a young child (less than 3 yrs old) exhibited greater overall parental investment than all others. In fact, they spent as much time on direct child care as homemakers and females with low occupational status. Husbands did not significantly vary their investment of time as a function of the wife's ability to provide resources.

Group Selection Inferred From Breast Asymmetry Of Playboy Centerfold Twins

Patrick Dempsey

Unaffiliated, 5091 Citation, Cypress Ca 90630

Playboy has an archive of many millions of unpublished Centerfold photographs. Often, these are published, un­retouched in special Playboy Newsstand Editions. From these un­retouched photos we have discovered roughly a 20% asymmetry rate in centerfold areolas, including asymmetry reversals in four sets of Playboy twins. These rates are roughly similar to percentages found by others who propose a "Bad Genes" concept for human breast asymmetry. We review the evolution of primate secondary sex characters leading to asymmetry in human bread, breast baldness in percentages consistent to that of left handers in all­star baseball teams and common in human brain physiology. Some argue genetic noise accounts for variation of human physical attraction. We propose that human asymmetry may be evidence of a "Group Phenotype" an artifact of group selection, rather than a sign of parasite load. We argue that brain and breast asymmetry are most likely linked by an as yet undiscovered developmental process common to both. That developmental hormones working to create asymmetries in the human brain sometimes spill over to cause asymmetry in the human breast. We propose that the most likely generator of this adaptive "Group Phenotype" are the newly discovered Dynamic mutations or trinucleotide repeats responsible for rare neurodegenerative disorders such as Huntington's Disease and others.

Protocultural Aptitudes In Early Mother­Infant Interaction

Ellen Dissanayake

c/o Franzen, 180 Colman Drive

Port Townsend, WA 98368

The close mother­infant relationship is characteristic in primates, and especially in humans where infants are highly altricial. In most if not all human societies, ritualized face­to­face play between mothers and infants ­­ using facial, vocal, and kinesic signals ­­ provides significant neurological, emotional, intellectual, linguistic, and psychosocial developmental benefits for infants. Organized in jointly­maintained temporal patterns with simultaneous or overlapping (coactive) and alternating (turn­taking) sequences to which both partners respond in split­seconds, these signals also correspond to universal expressive features indicative of motivation for social contact (affiliation) found in nonverbal communication in adults, rudiments of which are observed in mother­infant and other dyadic behaviors in some primates. It will be suggested that the sensitivities and competencies evolved by human infants and mothers that enable them to participate in these early interactions not only contributed ancestrally to infant survivorship and enculturability, as is well accepted, but may also underlie the origins of some human cultural behaviors.

Jealousy As A Function Of Rival Characteristics.

Pieternel Dykstra & Bram P. Buunk

University of Groningen, The Netherlands

According to evolutionary psychology men and women differ in the characteristics they value in a partner. Men value physical attractiveness in women since a woman's physical attractiveness is related to her fertility while women value dominance in men since dominance is related to a man's ability to provide resources. Since jealousy is evoked by characteristics of the rival that are perceived to be important to the other sex, it was predicted that jealousy in males would be influenced by the rival's dominance while jealousy in females would be influenced by the rival's physical attractiveness. In an experiment participants were presented with a scenario in which their current (real or imagined) partner was flirting with an opposite­sex individual. Next, participants received one of four profiles of the individual flirting with their partner. Profiles consisted of a photograph (low or high in attractiveness) and a personality description (low or high in dominance). Consistent with an evolutionary model of jealousy, females exposed to physically attractive rivals reported more jealousy than females exposed to average attractive rivals. Males exposed to physically atractive, compared with average attractive, rivals did not report more jealousy. Males exposed to rivals high in dominance reported more jealousy then males exposed to rivals low in dominance, while females exposed to rivals high in dominance, compared with rivals low in dominance, did not report more jealousy.

Individual Actors and Systems­Level Effects

Rada Dyson­Hudson and Dominique Meekers

Department of Anthropology, Binghamton University, New York

Sociology/PRI, Pennsylvania State University

Life histories of more than 11,000 South Turkana pastoralists were recorded, including sectional affiliation, year birth, and (where relevant) year marriage, year death, year migration, and reasons for migration. The sample is (as nearly as possible) all the descendants, living and dead, male and female, pastoralist and non­pastoralist, of 63 South Turkana elders born between 1860 and 1917. Information about wives of the male members of each genealogy was also collected. The data allow an analysis of migration across ecosystem boundaries in the context of the uterine and polygynous family; allow retrospective longitudinal analysis of migration across ecosystem boundaries for an approximately 90 year time span, and provide information on the relationship between individual behavior and the "functioning" of the ecosystem. They show that, although decisions about leaving the pastoral sector are made by individual South Turkana pastoralists seeking alternative sources of economic support, the net effect of these individual decisions on the ecosystem is toward regulating population with respect to resources.

Comparing the Sexes: Feminism, Science, and Interpretation

Alice H. Eagly

Northwestern University

Comparing the sexes is a research activity that offers many scientific and ideological challenges. Feminist discourse, in particular, often trades on claims about the presence or absence of differences between the sexes. To place the study of sex­related differences and similarities on a better scientific footing, psychologists have turned to quantitative synthesis as a method for integrating research findings across studies. The method is especially informative for examining sex­related differences because the large numbers of psychological studies that have compared female and male behavior render generalizations based on narrative reviewing especially unreliable. These meta­analyses have provided a more scientifically adequate database, but they do not yield interpretations. Although evolutionary psychology provides a framework for interpreting certain sex­related differences in behavior, alternative social psychological frameworks provide equally powerful frameworks. In particular, social role theory maintains that sex­related differences are influenced by gender role expectations that are derived from the specific family and occupational roles that women and men occupy in the society. Over time, women's and men's roles change as the economy evolves, and these gender roles slowly change. In contemporary post­industrial societies, men's and women's roles have become somewhat more similar as the majority of women have entered paid employment. Nonetheless, social role theory predicts only modest erosion of sex differences, because occupations remain moderately sex­segregated with women concentrated in occupations believed to require feminine attributes and men concentrated in occupations believed to require masculine attributes. In addition, domestic work is carried out mainly by women, and women remain moderately economically dependent on men.

Human Breats Disguise Fertility And Mensuration Signals It Occurence.

Dorothy Einon.

Psychology Department, University College London, Gower Street, London, WC1E 6BT

Alexander & Nooman (1979) suggest that hiding of oestrus and constant receptivity in women evolved to induce men to parent. By themsleves such mechanisms are insufficient to induce male parenting. Men who locate women experiencing ovulatory cycles have a 1:14 chance of meeting fertile woman. Odds which are not dissimilar to males of species who share fertile females with a large number males. The interval between births in women is divided into three phases: pregnancy, lactation, and waiting time. Women only ovulate in the later. To induce men to commit women must hide both ovulation and lactation amenorrhea. It is suggested that the growth of breasts at puberty are an effective means of doing this. It is further suggested that mensuration acts as a signal for the onset of fertile cycles, but that such signals are only available to men who stay with women. Low fertility and high rates of spontaneous abortion maintain that commitment over time because the odds of finding a woman mensturating are always higher inside the relationship than outside.

Alexander R.D. & Nooman, K.B. Concealment of ovulation, paternal care and human social evolution. Evolutionary Biology and Human Social Behavior, N.A. Chagnon and W. Irons. Duxbury Press, North Scituate, MA. 1979.

The Dating Alternatives Questionnaire: An Evolutionary Approach to Comparison Level for Alternatives

Bruce J. Ellis

Psychology Department, Sloan Hall 235, Central Michigan University,

Mt. Pleasant, MI 48859

From an evolutionary perspective, one's "mate value" is a function of the degree to which one possesses attributes that reliably correlated with the capacity to promote reproductive success in members of the other sex in ancestral environments. From a social exchange perspective, one's "market value" as a mate is a function of the degree to which one possesses whatever attributes are valued by the other sex in one's culture. Both evolutionary and social exchange theorists emphasize that individuals make social comparisons between self and others and use these comparisons to form concepts about one's own value as a mate. Social exchange theorists have developed social comparison measures to assess individuals' global perceptions of relative market value within dyadic relationships. In two studies of dating couples (N = 227 heterosexual dyads), the present research develops social comparison measures to assess individuals' specific perceptions of relative mate value within dyadic relationships. These content­specific measures are based on strategic modeling of specific adaptive problems encountered in mating relationships throughout our evolutionary history. Compared to the past global measures, these content­specific measures significantly increase our ability to predict feelings of love for one's dating partner and investment of time in one's dating relationship.

Social Hierarchies And Reproductive Success At The Individual And Group Levels

Lee Ellis

Minot State University

ellis@warp6.cs.misu.nodak.edu

This paper will extend a recent review of the literature on relationships between dominance in nonhuman animals and reproductive success (Ellis, 1995) by exploring theoretical issues surrounding the relationship between all types of social hierarchies (including human social status) and reproductive success. I will argue that most animals who form social hierarchies may realize a reproductive benefit at both an individual and group level. While those highest in the social hierarchy are expected to usually derive greater reproductive benefit than those who are lowest in the hierarchy, there are conditions under which this should not be true.(97 words)

Evolutionary Studies Of Animal Families: What Can They Tell Us About Ourselves?

Dr. Stephen T. Emlen

Jacob Gould Schurman Professor

Section of Neurobiology and Behavior Cornell University

Ithaca, New York 14853­2702

E­mail: ste1@cornell.edu

Phone: (607) 254­4327

Fax: (607) 254­4308

Darwinian thinking is making important inroads into the social sciences. This is exemplified by the growing discipline of Evolutionary Psychology, which attempts to understand human behavior by positing that many of our social behaviors and emotions represent heritable adaptations that were selectively advantageous for life in our ancestral (pre­agricultural, pre­industrial) human environment.

This evolutionary framework for viewing behavior, in turn, derives from Behavioral Ecology, the discipline that studies the adaptive bases of animal social behaviors. I will review some of the basic assumptions of Behavioral Ecology, discuss the importance of animals as model systems, and review general patterns of family dynamics that occur in non­human species. I will argue that an evolutionary theory of the family is at hand, and that we can learn much about ourselves by examining our own family dynamics within this evolutionary framework.

Cross­sex Differences in Incest: Towards an Evolutionary Explanation of

Patterns in Myth and Incidence

Daniel M.T. Fessler

Dept. of Anthropology, University of California San Diego

9500 Gilman Dr., La Jolla, CA 92093­0532

email dfessler@weber.ucsd.edu

Although myths containing Oedipal themes have been identified in many cultures, stories concerning the Electra configuration are rare. In contrast, father­daughter incest appears to be more common than mother­son incest. These two patterns reflect fundamental differences between male and female sexuality. Psychoanalytic accounts of the Oedipus and Electra complexes do not adequately explain differences between the sexes. Moreover, these approaches focus on the young child as a sexual actor, yet it is the older child who constitutes a realistic rival for the same­sex parent. In contrast, both cultural anthropologists and evolutionary psychologists focus not on sexual rivalry, but on the conflict over resources which occurs between parent and child. Evolutionary psychologists have also explored father­daughter incest as a case of conflicting reproductive strategies. However, the emphasis of these explanations is misplaced. Rather, parent­child incest is best viewed as a special kind of adultery. Because parental investment differs across the sexes, there are significant differences in reactions to adultery. Likewise, because the reproductive concerns of men and women differ, mother­son incest is a significant threat to fathers, but father­daughter incest is far less threatening to mothers, and may even be advantageous sometimes.

Rationality As An Adaptive Adaptation

James H. Fetzer

Department of Philosophy

University of Minnesota

Duluth, MN 55812

The relationship between causality and rationality assumes an acute form from the perspective of evolution, since natural selection appears to be a causal process that functions independently of considerations of rationality. Once distinctions have been drawn between rationality of belief and rationality of action­­neither of which has to be conscious to organism or agent­­it becomes obvious that rationality of both kinds promotes attainment of goals, which is significant to evolution when those goals include survival and reproduction. Indeed, given these goals, behaviors that are adaptive are rational and be­ haviors that are rational are adaptive. Rationality is especially useful in coping with genetic lag. The emergence of mentality thus provides a means toward the end of acquiring more efficient, effective, and reliable mechan­ isms to serve this function. Relative to the evolution of species, natural selection is a causal process yielding rationality as an adaptive adaptation.

By Accident, or By Design.

Larry Fiddick, Leda Cosmides, and John Tooby

Dept. of Psychology, Dept. Of Psychology, Dept. of Anthropology

University of California, Santa Barbara

It has been suggested that one of the design features of a psychological mechanism for detecting cheaters is that it distinguishes between intentional and accidental violations of a social contract. A 'look for cheaters' program should be activated only in those cases where individuals stand to illicitly benefit by violating rules and it should not be activated when a person accidentally breaking the rule does not stand to receive an illicit benefit. Experimental evidence demonstrating that people do make such a distinction has lent support to the view that cheater detection is governed by a special­purpose, cognitive mechanism.

However, psychological experiments on reasoning demonstrating that people are able to detect violations of rules other than social contracts, such as precautions, has been taken as undermining claims for the specialized nature of the underlying cognitive mechanisms. The possibility remains that there is a variety of specialized mechanisms. Were this the case, evolutionary arguments would suggest that social contract mechanisms and precaution mechanisms should diverge in terms of sensitivity to accidental violations. Whether one intentionally or accidentally violates a precautionary rule is irrelevant since any violation puts the violator in danger. We present evidence demonstrating that whether or not the violation of the rule was accidental influences the inferences people draw about social contracts, but not precautions, on formally identical cognitive tasks.

Daughters Of El Cid: Family Deterrrence Of Domestic Violence In Spain

Aurelio Jose Figueredo, Karen Bachar, and Janine Goldman­Pach

Behavioral Evolution And Development Group, University of Arizona

A telephone survey of battered and non­battered women with children under 12 years old was conducted in Madrid, Spain. This cross­national constructive replication was supported by a BRAVO/MIRT Grant (5T 37 TW00036) to Jose Ribeiro from the NIH Fogarty International Center. Four different subpopulations were sampled for varying degrees of risk to test if a woman's extended kin network protected her against spousal abuse. Three factors had previously predicted domestic violence in a Tucson, Arizona, study: (1) Sex, (2) Money, and (3) Paternity; a general factor for domestic violence included four subscales: (1) Verbal, (2) Physical, (3) Escalated, and (4) Sexual. The spatial distributions of the woman's relatives were weighted by their coefficients of relatedness; family support was also measured. A path analysis estimated the direct and indirect effects of the woman's kin on domestic violence. Kin densities both inside and outside Madrid were found to reduce domestic violence, although kin densities outside Madrid exerted lesser effects. Because higher kin densities inside Madrid predicted lower kin densities outside Madrid, the major difference was in family spatial distribution rather than absolute family size. Because these effects were not mediated by reported family support, the protective effects of extended kin networks were attributable to deterrence rather than support.

Family Environment, Stress Response, and Health Among Children in a Caribean Village

Mark Flinn, Mark Turner, & Barry England

U Missouri, Northwestern U, & U Michigan Hospitals

We investigate daily variations in glucocorticoid stress response, immune function, and health among children in a natural (non­clinical) environment. The study involves 262 children aged one month ­ 18 years residing in a rural village on the east coast of Dominica. Fieldwork was conducted over a nine­year period (1988­1996). Research methods and techniques include: immunoassay of saliva samples (N = 24,560), systematic behavioral observations, psychological questionnaires, health evaluations, medical records, informal interviews, and participant observation.

Analyses of data indicate that childhood stress is associated with family environment. Children residing with caretakers that are nonrelative, stepparents, or single parents without kin support have different cortisol profiles than children living in nuclear, extended, or single parent with kin households. Temporal changes in family relationships are accompanied by elevated cortisol levels. Children with histories of troubled family relationships during infancy commonly have unusual cortisol response profiles.

Stress is associated with child health. Children with higher average cortisol levels have more frequent health problems than children with lower cortisol levels. Temporal patterns of cortisol suggest that children undergoing stressful events are at higher risk for illness (diarrhea, influenza, common cold, asthma, rashes, etc.) during a two ­ six day period following unusually high cortisol levels. Concomitant with abnormal cortisol response is altered immune function; some chronically stressed children appear to have reduced cell­mediated (neopterin, microgloblin 2), humoral (s­immunoglobulin A), and/or non­specific (neutrophil recruitment via interleukin­8) immunity.

These results suggest that family environment has important effects on childhood stress, health, and psychological development. The mind of the human child appears especially sensitive to interactions with caretakers. Glucocorticoid stress response to family trauma appears to allocate somatic resources to mental function and protection from auto­immunity.

Supported by NSF BNS 8920569, NSF SBR 9205373, and NIH RR 07053 to MVF.

Neurohumoral Brain Dynamics Of Group Formation

Walter J Freeman

Department of Molecular and Cell Biology

University of California, Berkeley CA 94720

wfreeman@garnet.berkeley.edu

The biological basis of consciousness can be explored with two assumptions: that animals are conscious in ways less complex than in humans, and that neural mechanisms are the substrate of mental processes. My main concern here is with a salient property of consciousness, namely the solipsistic isolation between different brains. How is it that we cannot be certain, by direct experience, what any other entity has in its consciousness, whether it is an animal, a machine, or a fellow human being? Research on brain waves (EEG) offers a mechanistic answer to this fundamental epistemological question. It is because brains are self­organizing systems that are closed with respect to meaning. This is shown by following the flow of sensory input into the olfactory, visual, auditory, and somesthetic systems and finding that input is replaced by spatial patterns of neural activity, which are uniquely constructed by brains as meanings. The question then follows: how do humans surmount the resulting solipsistic isolation and engage in social action based in mutual understanding? A proposed answer is that human brains already contain mammalian neurohumoral mechanisms for pair bonding, and that these have been adapted through biological and cultural evolution to individual, familial, tribal, religious and political conversion processes. (204 words)

A Biological Basis for Group Mind without Group Awareness

Walter J Freeman

Department of Molecular & Cell Biology

University of California at Berkeley

The concept of 'group mind' has been derived from observation and analysis of cooperative behavior through sociology and anthropology, so that its biological basis is unclear. In particular, the question arises, whether the property of awareness can be assigned to groups in something like the way that it is conceived for individual minds, as, for example, to the pygmies of Central Africa (Arom 1991), who cannot explain how they make their communal music together. Neurophysiological explorations by Libet (1994) and his colleagues have shown that the complex integrative process, which results in awareness of a stimulus, requires about half a second, although the time of stimulus onset is back­dated close to its origin. Evidence for a comparable delay has been found for awareness following the genesis of self­paced actions. A hypothesis is presented here that socialization leading to group actions depends on a neurohumoral mechanism for 'unlearning', which has evolved from a mammalian process supporting reproductive behavior, and which enables inculcation of cooperative maternal/paternal activities. The implication is that human socialization through unlearning gives a basis for preconscious actions embedded in past learning, such that the rapid exchange of behavioral signals during cooperation can result in group intentional behaviors without the necessity or opportunity for individual reflection. Introspection can interfere with the smoothness of group actions and, in any case, would appear always to follow the actions through elective individual processes of contemplative evaluation.

References

Arom, Simha (1991) African polyphony and polyrhythm: musical structure and methodology. Translated from French by Martin Thom, Barbara Tuckett, Raymond Boyd. Cambridge UK: Cambridge University Press.

Freeman WJ (1995) Societies of Brains. A Study in the Neuroscience of Love and Hate. Hillsdale NJ: Lawrence Erlbaum Associates.

Libet B (1994) Neurophysiology of Consciousness: Selected Papers and New Essays. Boston MA: Birkhauser.

Towards an Understanding of Human Skin Color in the EEA: Age­Related and

Sex­Related Meanings

Peter Frost

Department of Anthropology

Universite Laval

Male skin has more melanin and hemoglobin than does female skin, i.e., men are browner and ruddier; women, paler. The sexes differ in both "constitutive" pigmentation and "facultative" tanning potential. This sex difference begins at puberty when girls lighten in color; it may widen in adulthood as male constitutive pigmentation darkens in response to repeated tanning.

Within ancestral societies, i.e., bands of related families, the different complexions of men and women were the main source of skin color variability. Darker skin signified "man" and lighter skin "woman" (or "infant"© ­­­important information in band societies, where age and sex were the main social cleavages. Early humans may have thus prepared themselves for potential social interactions by using complexion and other visual cues to identify the type of encounter they might have to face (man­woman, man­man, woman­woman, or adult­infant) and adopting the appropriate state of readiness.

Over time, "hardwired" mental linkages may have formed between this visual cue, the type of encounter it called to mind, and the appropriate state of readiness.

"Footedness" in Parrots

Dr. Mildred Funk

Biology Department, Roosevelt University, Chicago

Through several centuries, published reports have claimed "footedness" in parrot species, suggesting that parrots have population preferences in limb use similar to human handedness. However, early parrot studies did not include many species, used small samples and took few observations of those individuals. More recently, several studies of parrots have found a left­footed tendency in 25­30 species and a right footed bias in several species of one genus, the Australian Rosella. This presentation briefly reviews the parrot literature and presents data on a species closely related to the Rosella, the New Zealand parakeet (Cyanoramphus auriceps). Of 13 birds tested, nine were right­footed, two were left­footed, and two used both feet equally in feeding behaviors. This right claw bias may be related to their ecological activities. This is a small sample and more subjects are being sought.

Variation in Developmental Imprecision: Implications for Evolutionary Psychology

Steven W. Gangestad

Department of Psychology

University of New Mexico

Albuquerque, NM 87131

sgangest@unm.edu

During the 1950s, Waddington, Lerner, Thoday, and others argued that selection should favor genetic properties (e.g., coadaptation, modifiers) that ensure developmental stability ­­ the precise expression of developmental design in the face of genetic and environmental perturbations (e.g., mutations, pathogens). These phenomena have received limited attention from behavior geneticists and evolutionary psychologists. This talk addresses several topics: 1) Evidence that neurodevelopmental disorders are partly a function of developmental instability; 2) Evidence that, even in nonpathological populations, variation in developmental instability affecting brain structure and function is present; 3) Reasons why selection has not driven out variation in developmental stability; 4) Implications of these issues for a major tension between behavior genetics and evolutionary psychology, namely, a universal design purported to exist despite substantial genetic variation in psychological phenotypes.

Invoking Alpha State to Treat Involuntary Subordinate Strategy

Russell Gardner, Jr., M.D.

Department of Psychiatry and Behavioral Sciences

University of Texas Medical Branch

Galveston, TX 77555­0428

Are there implications for considering depression not as a biochemical imbalance but as a brain­encoded result of natural selection? Animal model research suggests that depression may reflect an involuntary subordinate communicational strategy that had existed in animals ancestral to humans, involuntary as it occurs outside conscious control, subordinate and communicational because the characteristic behaviors communicate lack of threat, and a strategy in that the communicational state was "designed" by Darwinian selection. Other work concerns mania as a maladaptive also involuntary variant of a communicational state in which the individual signals "taking charge" as through possessing alpha status in a hierarchy. Use of serotonin­enhancing agents not only reverses depression in humans but elevates status in subordinate vervet monkeys. Case reports show that patients appropriately feel more "in charge" with serotonergic medications, although changes in actual status are less evident. Nonhuman/human contrasts may assist in intervention: large­brained humans have metaphoric capacities that allow one to be voluntarily "in charge" of life components. The shiver/ATP strategy therapeutically deploying this formulation uses shivering to illustrate ancient involuntary strategies. Humans more uniquely than other animals are able to use Allies in deploying Thought to analyze circumstances and capably Plan in order to forestall future problems.

Superior Spatial Memory of Women: Stronger Evidence for the Gathering Hypothesis.

Steven Gaulin, Donald McBurney, Trishul Devineni, and Christine Adams.

Department of Anthropology, and Department of Psychology, University of Pittsburgh.

Male and female college students played the commercial game Memory requiring them to recall the locations of previously viewed items, and also completed the 20­item mental rotations task. As is typical, males performed better than females (d=.67) on the mental rotations task. In contrast, females outperformed males by a large margin (d=.89) on the memory task. Performance on the two tasks was positively correlated for females but not for males. The reversal of the sex difference between the tasks suggests that spatial ability is not a unitary trait and that different kinds of spatial processing may have been important for males and females in the EEA. The Memory game appears to mimic the cognitive demands of foraging better that previous "spatial" memory tasks.

GROUP SELECTION: IT HAPPENS (IN HUMANS)

Francisco Gil­White

U.C.L.A.

Sound arguments have been made against the likelihood of group selection being an important force in non­human populations. These arguments, however, fail to apply to group selection amongst cybernetic (self­regulating) cultural units. This is because cultural cybernetics operates through conformist transmission (CT) and third­party punishment (3PP) to keep the frequency of certain memes (ideational or behavioral variants) at high frequency. These mechanisms are important because of their effects on migrants. If a migrant with a new meme enters a population, CT and 3PP will act to disfavor that meme, and therefore migration will often not lead to the rapid diminution of memic variation between groups that would make group selection of memes implausible. Group selection at the memic level will sometimes lead to the emergence of genetic adaptations because the cultural environment creates genetic selection pressures on group­living individuals. This still argues for species­wide genetic adaptations (in cases where the meme is stable enough and it is advantageous to hard­wire the meme), however, because selection amongst groups entails that ultimately all groups end up with such a stable meme, generating selection pressure across the species for genetic adaptations to it. Important psychological adaptations such as group­welfare altruism (i.e. of non­relatives) and the in­group/out­group phenomenon can be explained this way, whereas kin­selection and reciprocity explanations fail.

The Theory Of Patriarchy

Steven Goldberg/Chair/Sociology/City College/CUNY

This paper attempts to demonstrate, and explain, the universality (the presence in every society without exception) of three institutions:

1. Patriarchy: Male attainment of upper hierarchical positions.

2. Male Attainment: Male attainment of the high­status, non­maternal roles,

3. Male Dominance: The association of dominance with males in male­female encounters and relationships.

Even were there no direct physiological evidence, the cross­cultural evidence could be logically and parsimoniously explained only by positing a physiologically­rooted differentiation of male and female emotional/behavioral tendencies. Moreover, such a differentiation need not be merely posited; the physiological evidence is overwhelming.

Hierarchy, status, and member of the other sex elicit more readily from males (statistically­speaking, as always) the tendency towards dominance and attainment. Males are more willing to sacrifice other sources of satisfaction to these ends­­to do whatever is necessary and possible to attain position, status, and dominance.

Sociological explanations of the universalities fail. For example: explanations invoking socialization as primary cause do not explain, but merely beg the question: why does every society associate dominance behavior with males? Explanations emphasizing environment incorrectly treat environment as an independent variable, thereby failing to see that environment is given its limits by the psychophysiological differentiation and failing to explain why the environment is never sufficient to alter the direction imposed by the physiological.

Biological scientists have demonstrated the importance of neuroendocrinology to sex differences in behavior, but have lacked the cross­cultural evidence required for specificity of the social effects of the differences. This paper attempts to provide such evidence.

Exchange, Appropriation, Partnering, and Other Active Evolutionary Strategies

Oliver R. Goodenough

Vermont Law School,South Royalton, Vermont 05068

ogoodeno@vermontlaw.edu

Evolution can be usefully­­if somewhat abstractly­­described as a process by which replicating systems increase the amount of information they possess which will be useful in the further replication of the system. The classic Darwinian model of evolution, coupled with a knowledge of genetics, suggests a kind of "branch and loop" process, in which randomly occurring change creates mutations which then are winnowed out through the process of natural selection. The power of this model, and of the "selfish" logic on which it operates, is considerable. Its power, has, however, tended to drown out consideration of other models by which systems can gain useful information, and thus evolve. These models include strategies for the exchange or appropriation of information; for the banding together of systems; and for the construction of organs of learned information. These models have particular applicability to the behavior of humans. They can work through a biologically rooted, evolutionarily sound logic which can be quite different from that of classically "selfish" genetically based evolution. In some cases, and depending on the level of organization at which one looks, these processes can produce "group" level evolutionary effects.(190 words)

Sexual selection, sexual dialectics, and evolution of social monogamy: a Darwinian­Feminist view

Patricia Adair Gowaty

Institute of Ecology, University of Georgia, Athens, Georgia 30602

Female control of own reproductive capacity, a feminist goal, is predicted by the anisogamy argument that says that some males will be under selection to manipulate and control females' reproductive capacities, providing selection pressure on females to resist. I call this control and resistance game "sexual dialectics"; it is a type of sexual conflict. I discuss how fitness benefits ­ for females of freely expressed behavioral female choice ­ theoretically fuel sexual dialectics. I provide a graphical model of how the control and resistance game between females and males organizes reproductive success variance of human males and predict patterns of male­male coalitions (both conscious and unconscious). I then use the game of control and resistance to predict extra­pair paternity as a function of variation in 1. women's reliance on male­controlled resources and 2. their needs for protection from dangerous men. Throughout, I note the correspondences in feminist and Darwinian thought, reflect on the (mis)understandings of proximate and ultimate causation that fuel debates both within and between the evolutionary biology and feminism enterprises, and show how sexual dialectics can be brought to bear on the problem of world population growth.

The Human Mating Game: The Battle Of The Sexes And The War Of Signals

Karl Grammer

Ludwig­Boltzmann­Institute for Urban Ethology

Althanstrasse 14

A­1090 Vienna/Austria

The main themes of the battle of the sexes in terms of evolutionary adaptedness are to render deception, to avoid deception and to secure investment. As a result humans evolved a number of strategies, behavioral and cognitive adaptions and like active female choice, strategies for establishing and maintaining relationships, strategies of male philandering and female sexual crypsis. The function of the latter is supposed to lie in the promotion of active female choice and pair­bonding. We have to keep in mind that as soon as cognitive and strategic adaptions exist, they also are open for exploitation. Therefore, we can expect a highly manipulative repertoire of behavioural tactics. In this talk I will present two experiments and an observational study that show manipulation tactics reaching from low level sensory exploitation over the direct control of cognitive processes in a potential mate to the machiavellistic use of culturally determined explicit sign codes. If male philandering is a successful mating strategy which exploits active female choice, we would expect an advantage for males who are able to detect ovulating females. Up to now no unambigous behavioral marker has been identified that may be perceived at the time of peak fertility and the evolution of female sexual crypsis seems to be complete. Indeed males have found a more direct way to find access to female brains and cycle state. One of the main components of male pheromones induces negative emotions towards males with one exception: the negative evalution of males disappears at midcycle. Male pheromones thus could function as a chemical device for the detection of ovulating females and the induction of ovulation itself. On the other hand if female sexual crypsis is a successful female strategy, females could use philandering males for their own purpose. Female sexual crypsis could serve in the choice of an optimal father or in the induction of sperm­competition. The female problem is that males are highly selective for female attractiveness. Although it is possible to use deception in this area, females have developed a chemical weapon which influences male decision making: female copulines. Female copulines equalize males ratings of females attractiveness, make ovulating females less attractive but balancing the loss of attractiveness by an increase in male testosterone levels at midcycle. In this view, female sexual crypsis indeed seems to be one of the main themes of the battle of the sexes. In an observational study in discotheques we found that females are able to use a culturally determined sign­code and explicit knowledge attached to the function of this sign code. Clothing not only signals personality features it also might signal behavioral tendencies. Females seem to have a way to access their cycle state and use explicit sexual advertisment through clothing accordingly. We found that unpaired non­pill taking females actually avoid to signal cycle dependent. Yet they still might be detected by males through their reactions to olfactory stimuli. Pill taking single females show the highest amount of sexual signalling and interest in males. Instead, non­pill taking females who have a partner but come alone use explicit sexual signalling at midcycle as measured by amount of skin shown, tigthness and skirt­length. Male behaviour tactics thus exploit female active choice and female behaviour tactics exploit male's mate selection preferences and their preferences for sexual signals. Intersexual signalling works on a broad range from levels where actual information processing of the brain is either influenced or exploited to the use of culturally determined sign codes turning the battle of sexes into a war of signals.

Postpartum depression as an adaptation to paternal and kin exploitation.

Edward Hagen

Department of Anthropology

University of California, Santa Barbara

(805) 893­2236 6500ehh@ucsbuxa.ucsb.edu

Given the high levels of investment required to successfully raise human offspring, mothers are vulnerable to exploitation by fathers and family members who fail to provide sufficient investment once the child is born. Mothers who fail to receive sufficient investment should defect from the infant. In order to maximize their inclusive fitness, however, low or non­investing fathers and family members can impose costs on her to prevent her from defecting. Imposing these costs may be cheaper than investing, but would not be free. Numerous studies of depression and spousal relations pre­ and post­partum support the hypothesis that postpartum depression (PPD) is a strategy by the mother to elicit greater investment from the father and family members by making a credible threat of defecting from the offspring. Mothers with PPD have little or no interest in investing in either the infant or themselves, and often have obsessive thoughts of harming the infant or allowing it to come to harm. During our evolutionary history, this would have dramatically increased the odds of infant mortality, forcing the father and family members to either increase their investment or cease paying the costs of coercion, which are now unlikely to pay off. This model may have implications for depression in general.

Reproductive Strategies in Restoration Comedy

Brian Hansen.

Professor of Theatre (Emeritus), University of New Mexico, Albuquerque, NM 87131

Crucial as it is to human affairs, it is not surprising that sex figures so heavily in theatre. However, our species' actual reproductive strategies are usually obscured by layers of idealism and religious cant. A rollicking exception is Restoration comedy. Here, reproductive strategies are center stage, so much so that moralists then and since have tried to label the plays a perversion...and a slander against human nature. Only since Darwin have we understood how true the plays are­­and why so funny. Bio­social theory lets us see clearly what is being disclosed in these plays and how "speaking the unspeakable" in public conforms to modern theories of comedy. Special reference to Wycherley's The Country Wife (1675) and Congreve's The Way of the World (1700).

Factors Influencing Successful Birth Outcomes

Mary Harmon*, Kathryn Coe**

*AIDS Research Consortium of Atlanta, Atlanta, GA

**Arizona Department of Health Services, Phoenix, AZ

Using data from the 1989­1991 birth subsystem of the vital statistics of a state in Southern Appalachia (n=84,510), we examine factors correlated with infant mortality or associated with morbidity that can profoundly affect the individual's life: birth weight, gestation period, congenital anomalies, and abnormal conditions. We compare a category of mothers who can be predicted to have increased access to resources (indicated by marital status and education level) with mothers who have decreased access. We then examine factors correlated with successful birth outcomes in each of these two categories: sociodemographic characteristics (age and education of mother and father), age differences between spouses, reproductive factors including prenatal care and weight gained, and risk factors such as medical conditions and prior terminations.

Cognitve Processing Of Physical Attractiveness By Males And Females

R. Glen Hass

Department of Psychology

Brooklyn College, CUNY

Brooklyn, New York 11210

Previous research has used self­report measures to examine attributes males and females desire in the opposite sex. Questions of the psychological mechanisms that underly these stated preferences have been left open. Using reaction time as a measure of mental processing of information, we have found differences between males and females in their cognitive processing of opposite­sex physical attractiveness information. Consistent with an evolutionary analysis, the results of six experiments with heterosexual participants show that: (1) males are more likely to spontaneously cognitively process physical attractiveness of females in terms of sexuality, while females are more likely to process physical attractiveness of males in terms of successfulness; (2) this effect holds only for processing of opposite­sex physical attractiveness; (3) within­sex, as well as between­sex differences in cognitive processing occur when thinking about an opposite­sex person's attractiveness for a short­term vs. a long­term relationship; and (4) predicted similarities between males and females also emerge in the cognitive processing of attractiveness for a long­term relationship.

Herd Behavior in Market Trading?

by Richard Heaney

Dept of Commerce

Univ of Queensland

Brisbane 4072, Australia

The world share markets appear to follow regular boom and bust periods but the rather catastrophic which have occurred in 1929 and 1987 seem beyond most economic theories. Market players commonly described the market as overheated prior to the 1987 crash and many of the "smart" players had left the market some time before the crash. Could the extreme fall in the market in October 1987 have resulted from some sort of "herd" behaviour?

The basic question behind the research is why did the market fall so far and so quickly? Analysis will centre on price movements and information releases around the crash period and experiments based on simulating the crash period characteristics of rapid falls in share price and restrictions on the ability to trade and analysing investor reactions.

Self­Deception And Overconfidence: Evolutionary Adaptations To Disguise Human Pursuit Of Self­Interest?

Mario Heilmann

Department of Psychology

University of California at Los Angeles

<mheilman@ucla.edu>

To allow the benefits of higher intelligence, special mechanisms are needed to selectively blur our logic wherever unbiased thinking would prove detrimental. Social sanctions hit those who see the hypocrisy of their society, the arbitrariness of its norms, the emptiness of its initiation rites and gods. Galileo and many other creative thinkers were persecuted for espousing an objective truth; uncritical belief in socially created truth usually proves to be much safer.

We tend to steadfastly maintain a rosy image of ourselves as honest, rational and self­aware altruists living in a just society, in spite of overwhelming evidence to the contrary. Some of the mechanisms identified by psychological research are: positive illusions, self­serving and other biases, selfish mating strategies, overconfidence, conformity, impression management, etc. Often, well­being is positively correlated with these cognitive distortions. Could it be morally wrong to do research and disturb the self­deceptive positive illusions?

Awareness of self deception is the first step towards overcoming it. Therefore, self deception about self deception is needed to keep the system intact.

UNTANGLING ECONOMIC CONFOUNDING OF FITNESS ISSUES

Kathryn B. Held

Department of Anthropology

University of Oklahoma

Norman, Oklahoma 73019­0535

The success of sociobiological logic in deductively revealing biological mechanisms driving behavior does not always carry over to inductive explanations of observed phenomena. Interpretation of the biological foundations of human behavior is frequently hampered by confusion between fitness and the often intertwined­­yet sometimes causally unrelated­­factors of economics or dominance. Analysis of particulars at the level of individual or household decision­making can provide clues to unravel underlying behavior motivation. These issues are illuminated through re­evaluation of impoverished groups in which biased parental investment in favor of daughters has been noted as following the predictions of the Trivers­Willard proposition that natural selection favors parental ability to adjust the sex ratio of offspring. Even when females average more children than do males, parental bias does not necessarily originate from a generalized evolutionary trait if daughters also provide an economic advantage or will enjoy economic advantages themselves. Untangling these competing hypotheses need not be consigned to the dusty shelves of unanswerable ontological conundrums. Methodology using deduction of the hypothetical extensions of each leads to inductively testable hypotheses.

Psychological Models Of Environmental Unpredictability: Related To Developmental Life History Strategies?

Elizabeth M. Hill, Ph.D.

The University of Michigan Alcohol Research Center

Human life­courses vary in the degree of risk taken in forming families and choosing careers or educational pathways. In particular, decisions made at various points have been defined as risky versus conservative or as reflecting short­term versus long­term strategies. Effectiveness of risk­taking will depend on the present and future benefits and costs, compared to available alternatives for gaining economic and social resources for family formation and reproduction. One's assessment of costs and benefits depends on both actual environmental characteristics and personal characteristics. A conceptual model is presented of a factor that may influence such decisions, one's mental model of the future environment, especially the predictability and amount of resources available in the future, in comparison to the present. Current measures of a "predictability schema" are described, such as Future Orientation, Causal Uncertainty, Self­efficacy, and Locus of Control. We present evidence for individual differences, evidence that such differences relate to developmental experiences of environmental unpredictability, and evidence that one's mental model is associated with risk­taking behaviors. The relationships among constructs in the conceptual model are illustrated using studies of families with an alcohol­dependent parent, which can manifest a variable and unpredictable family environment even though the average level of economic resources may be high. (Supported by NIAAA grant P50 AA0738)

"Quantity" And "Quality" Fathering Strategies: Not All Men Follow In Their Fathers' Footsteps.

Linda R. Hirsch

Department of Psychology/Weiss Hall (265­66)

Temple University

Phila., Pa 19122

Belsky et al. (1991) argue that the adoption of a "Quantity" reproductive strategy (early puberty, multiple short­term sexual relationships, little paternal investment) is adaptively based on a stressful rearing environment and insecure attachments to parents whereas a "Quality" strategy (late puberty, pair­bond with substantial paternal investment) is based on the opposite. These ideas was tested with 108 young male subjects who rated (a) their perceptions of their fathers' fathering, (b) attitudes about the approporiate roles for mothers and fathers, and (c) their own fathering intentions. Factor analysis generated three factors: 1) Quality males, fathered by Quality fathers, 2) Quantity males, fathered by Quantity fathers, and 3) "new" Quality males, fathered by Quantity fathers. Factors 1 and 3 involved egalitarian attitudes about sex roles and intent to invest substantially in fathering, consistent with pair­ bonding and substantial paternal investment. Factor 2 entailed acceptance of fathers' fathering and "traditional" attitudes about separation of sex roles. Correlations of factors with markers of stressful rearing and sexual behavior suggest that low paternal investment fathers can provide stresses that, contrary to Belsky et al., are percieved by some sons as extreme and detour them toward a Quality strategy.

Game Theory and Reciprocity

E. Hoffman*, K. McCabe** and V. Smith*** (presenter)

*Iowa State University, **University of Minnesota

***University of Arizona

There are now a number of two person extensive form bargaining games, conducted under conditions of anonymity, in which cash motivated experimental subjects do not satisfy the predictions of noncooperative game theory. They cannot, however, be said to be irrational: in strategic games, subjects as a whole tend to collect more money from the experimenter­­and thus provide more efficient social outcomes­­than predicted by noncooperative game theory.

We examine decision making in two­person extensive form game threes using nine treatments that vary matching protocol, payoffs and payoff information. Our objective is to establish replicable principles of cooperative versus noncooperative behavior that involve the use of signalling, reciprocity, and backward induction strategies depending on the availability of dominated direct punishing strategies, and the probability of repeated interaction with the same partner. We find surprising support for cooperation under complete information even in various single­play treatments. Only under private information do we observe strong support for noncooperative game theory.

These results are consistent with the reciprocity hypothesis of evolutionary psychology, but involve more than the "punishment of cheaters"; in particular trust plays an important role.

Intellectual Surplusage: The Role Of Bipedalism And Neonatal Head Trauma

Sean C. Hogan & Gordon G. Gallup, Jr.

Department of Psychology

State University of New York at Albany

Albany, NY 12222

email: s1707@albany.net

Since early Homo, human evolution has been dominated by two opposing trends. There has been a continued refinement in bipedal efficiency resulting in a narrow obstetrical outlet, in addition to an increase in overall brain size. This has led to the development of a species with difficulties in parturition that are unique when compared to other great apes. The tight fit between the head of the human neonate and the maternal obstetrical outlet has resulted in selection for a more flexible skull at birth. The extensive system of fontanelles and suture zones allows the skull to be molded as it makes it's way through the birth canal.

Although the flexibility of the neonatal skull makes possible the delivery of a large brained neonate, it has the disadvantage of increasing the risk of birth related and environmentally induced brain damage. For human infants head trauma is the leading cause of morbidity and mortality. Surplusage states that larger brains have been selected for in Homo to compensate for the inevitability of early neurological insult. Neural mechanisms, such as plasticity, utilize surplus cortical tissue to replace that which has been damaged through the birth process and the postnatal environment.

Teaching Human Mating: Handling Student Criticisms

Harmon R Holcomb III

Department of Philosophy

University of Kentucky

Lexington, KY 40506­0027 e­mail: Holcomb@ukcc.uky.edu

Students may not voice them, but each student has his or her own misgivings about evolutionary studies of human mating. If we don't deal with them, student misunderstandings will prevent acceptance of evolutionary findings as factual. I turned their resistance into a learning tool in teaching four popularizations: Buss's The Evolution of Desire, Batten's Sexual Strategies, Ridley's The Red Queen, and Wright's The Moral Animal.

I shall describe teaching methods to: identify the misgivings; give the class a sense of the whole set of scientific, political, and philosophical objections; expose misunderstandings behind most objections, focus on central issues in evaluating evolutionary studies, and facilitate learning through essays that develop a student's stand on the issues.

Women's Reluctance To Defend Their Gender Interests

Annette Hollander, M.D.

Department of Psychiatry, UMDNJ, New Jersey Medical School

Newark, NJ 07103­2714

E­mail: hollanan@umdnj.edu

Men's control of political power, resources, and women's decisions about reproduction clearly increases male reproductive success. Some evolutionary biologists have suggested that there "should be strong selection on women to resist". On the contrary, there is an unexplained, observed lack of resistance. Even in contemporary USA, where women can be economically independent and could form a voting majority, women still voted against equal rights, and 1/3 support legislation that would remove from women decision­making about their own pregnancies.

Evolutionary theory illuminates why the enterprise of feminism is so difficult. For example, selection operates on behaviors that maximize the number of grandchildren. Sexual selection predicts that female behavior that endangers the reproductive success of sons will be selected against if the disadvantage to sons outweighs the benefit to daughters. Other factors discouraging challenge to male dominance include female­female intrasexual competition, aspects of primate alliance behavior, and some uniquely human culture­biology interactions, as well as proximate psychological mechanisms. Understanding these obstacles and the environmental contingencies that affect them is necessary to continue the movement toward empowering women.

Perceptions of Landscape and Environmental Preservation

Robert Hood

Graduate Assistant

Department of Philosophy

Bowling Green State University

What is the relationship between perceptions of landscape and attitudes concerning environmental preservation? I review evidence that there exist cross­cultural preferences in humans for certain landscape types and that these preferences are a result of evolutionary pressures. For example, humans are predisposed to prefer savannah environments. These preferences exist even in very young children, and exist even if the individual has never experienced the landscape directly. There is evidence that people prefer structural features of landscapes such as complexity, coherence, legibility, and "mystery." Conversely, people are indifferent to, or have aversions to, rainforests, wetlands, and deserts that lack these structural features. But rainforests and wetlands are just the sorts of areas that biologists and environmental managers urge that we preserve because of their biological value. I argue that, if landscape preferences are in fact the result of evolutionary selection pressures, these findings may have applications in environmental management and public policy concerning parks and wilderness areas. However, more work needs to be done on the models that explain how evolutionary pressures shaped landscape preferences in humans before such applications are possible.

'Thou Shalt Not Covet Thy Neighbor's Wife...Unless Thy Neighbor Is A Sibling'

Kelly Hornbeck and Stephanie L. Brown

Arizona State University

To the extent that the experience of sexual jealousy is proportional to the magnitude of reproductive threat imposed by an infidelity, and to the extent that gains in inclusive fitness may off­set the costs associated with infidelity, individuals should be less jealous of a related interloper than of a non­related interloper. In order to test this hypothesis, 100 undergraduate A.S.U. students responded to a hypothetical jealousy­provoking situation in which their partner was described as being sexually involved with either their sibling, best friend, co­worker, or a stranger. Participants indicated their likely affective and behavioral reactions. As predicted, those subjects who imagined an infidelity involving a sibling reported experiencing less behavioral jealousy then the subjects who imagined an infidelity with a non­relative. These results are discussed in terms of the adaptive advantages of polygamy within groups of kin.

Sexually Transmitted Diseases And Human Evolution: An Insight Into The Development Of The Nuclear Family.

Ronald S. Immerman, M.D.

Department of Psychiatry, Case Western Reserve University,

MetroHealth Medical Center Campus, Cleveland, Ohio 44109.

In addition to an immediate concern for the public health, sexually transmitted diseases (STDs) are also argued to have driven selected characteristics of human evolution over the millennia. STDs directly impair reproduction through increased infertility and infant morbidity. Increased number of sexual partners is an important predictive marker for increased STD­risk. Characteristics (e.g. dominance and sexual displays) which maximized the number of sexual partners would have been negatively selected. Those characteristics (e.g. consort behaviors, pair­bonding) which minimized the number of sexual partners would have been positively selected. A relationship is proposed between (i) changing mating behaviors secondary to STDs and/or STD­avoidance and (ii) the development of the nuclear family.

Sex, Gender, and Emotionality in Chinese Society and Chinese Studies

William Jankowiak (University of Nevada, Las Vegas).

In this paper I will explore the various perspectives China scholars use to analyze the Chinese construction of gender and sexuality. Particular attention will be given to the construction of gender stereotypes which demonstrate a remarkable ability to persist in spite of transformation in social roles. My study conducted during the 1989's in Huhhot, China found consistency in the use of gender stereotypes that is direct contradiction with the excepted cultural explanation. It is more consistent with the emerging evolutionary psychological research that holds gender differences reflect innate differences between the sexes. My study concurs with Lauthman et al study of American stereotypes by noting that the social psychological explanations used to explain gendered personality traits cannot account for the persistence in certain forms of gendered behavior. The theoretical implications for accessing the validity of contemporary studies of gender and sexuality in Chinese society and beyond will be explored.

Group Nepotism And Human Kinship

Doug Jones

Cornell University

dmj5@cornell.edu

If two or more individuals act collectively to assist their mutual kin, the optimal level of altruism will be higher than if each acts individually. This suggests, given the human aptitude for collective action, that human beings may have psychological adaptations not only for individual nepotism but also for group nepotism­­adaptations leading people to create and maintain solidary groups enforcing an ethic of unidirectional altruism toward kin. Human kinship systems have a number of features that seem more consistent with group nepotism than with egoism or individual nepotism.

1) Human kinship commonly features an "axiom of amity", a presumption that kin are entitled to aid independently of their ability to reciprocate or coerce However, human kinship systems commonly also include a distinction between domestic and jural domains; kin altruism in the jural domain is socially imposed altruism.

2) Human kin groups come in many sizes, ranging from families to clans, lineages and tribes of thousands of people.

3) Relatedness as defined by human kinship systems generally differs systematically from biological relatedness, and kin categorization is often carried out in ignorance of the exact genealogical connections between the individuals involved; even individuals known to be genealogically unrelated may be accepted as kin.

The theory of group nepotism may have implications for a number of research areas in the social sciences. I conclude by focusing on two; demand sharing of food among hunter­ gatherers and modern ethnonationalism.

Wealth and Surviving Children in American Men and Women.

Debra S. Judge

Dept. of Anthropology

University of California, Davis.

The overall relationship between the number of surviving biological children and residual wealth (the log of estate value after adjustment for purchasing power) is significant and positive for Sacramento, CA men during the last 100 years. There is no overall relationship between wealth and numbers of children for women. Micro­historical analysis of the 100 year period in 5 year increments indicates that the association of wealth and reproductive success in men shows no consistent change over time. The positive correlation for women between 1890 and the 1930s of terminal wealth and surviving children gives way to a negative correlation thereafter. Macro­historical comparisons between the Sacramento population and 18th and 19th century New England samples provide a baseline of comparison for contemporary patterns of change in residual wealth and lifetime reproductive success.

Every Man Has His Price: Torts, Distress, and a Fitness­Based Scale for

Compensatory Damages

Charles N. W. Keckler

Human Evolutionary Ecology Program

Department of Anthropology, University of New Mexico

Albuquerque, NM 87131 (cnwk@unm.edu)

Society (through the courts) and its most prominent counselors (economists and lawyers) have long struggled to come up with the cash equivalent, for instance, of a dead or disabled child. Though clearly difficult, this must be done if torts of wrongful death are to be redressed, and forces us, as a practical matter, to confront issues of profound theoretical importance. As with disfigurement or loss of fecundity, the Darwinian sees the damage here as a loss of potential fitness. Currently, the law glosses these difficult­to­price but clearly harmful torts by the degree of pain and suffering they generate. This may work somewhat, if clumsily, due to the loose evolved connection between negative emotional states, stress, and fitness loss. But it is a vague standard that naturally produces highly unpredictable settlements, and by treating reproductive capacity as a core interpersonal utility measure, a more consistent standard can be generated ­­ even in a misguided population that no longer maximizes fitness. I conclude with some general thoughts about how cultural regulation of social behavior (i.e. law) mediates between our inherent biology and economic interaction.

The Origin of Teleological Conceptions

Deborah Kelemen

Department of Education,

University of California, Berkeley.

Teleological reasoning ­ reasoning based on the assumption of purpose, design or function is a fundamental aspect of adult cognition. We wonder about the goals underlying people's actions and view human artifacts as created for a purpose. We also construe biological structures and processes in terms of functions. Drawing on developmental research, this paper addresses two questions: Why do we think in teleological terms? How did this tendency originate? Keil (1992) argues that the teleological bias evolved as a mechanism for drawing inferences about living things and is the foundation of an intuitive biological theory. An alternative proposal (Kelemen, 1996), is that teleological reasoning derives from children's knowledge of intentional behavior and is not inherently restricted to any category of phenomena: In the absence of scientific knowledge, preschoolers may draw the same conclusions as adults did prior to scientific advances such as Darwinism, and view virtually everything as intentionally caused for a purpose. Several findings are presented supporting the notion that, unlike adults, preschoolers' broadly view natural objects (e.g., mountains), artifacts (clocks) and biological organisms (tigers) and their parts as "made for something". These and other findings on preschoolers' function concepts and their beliefs about origins, are discussed in relation to the claim that there is an innate "teleological stance".

Evolutionary Psychology in the Workplace

Heidi Keller­Glaze, Bruce J. Ellis, Stephen M. Colarelli

Psychology Department

Sloan Hall, Central Michigan University

Mt. Pleasant, MI 48859

Much of human evolutionary history was characterized by a division of labor by sex not only on the basis of hunting and gathering but also fighting and urturing. This division meant that certain group activities engaged in primarily by ancestral females (communal childcare and gathering) differed profoundly from certain group activities engaged in primarily by men (hunting large animals and coalitional aggression). Because group­level hunting and fighting entails solution of different adaptive problems than group­level gathering and childcare, selection would have diverse cognitive mechanisms between the sexes underlying thought, feelings, and behavior in groups. In this paper, we review the literature on sex differences in competitive and cooperative behavior in groups. Males tend to form instrumental coalitions organized around competitive, goal­directed activities such as hunting, sports, and politics. Within male groups, interactions emphasize joking, competition, testing of masculine prowess, and exercise of power and influence to establish dominance hierarchies. These characteristics of male groups are pervasive in many professional work groups and may constitute social environments that are inhospitable to women. We address the implications of sex differences in competitive and cooperative psychologies for understanding women's participation and functioning in modern workgroups. We discuss strategies that could be used to enhance women's comfort and performance in workgroups.

Embarrassment and social life: The study of a social emotion

Dacher Keltner

University of Wisconsin­Madison

In this paper I address two questions concerning embarrassment, an emotion that imbues social relations but has long been neglected by emotion researchers. First, is embarrassment a distinct emotion? The evidence indicates that the antecedents, nonverbal display, and autonomic physiology of embarrassment are distinct from those of similar, theoretically relevant emotions, including shame, guilt, amusement, fear, and sadness, and share the dynamic and temporal characteristics of well­studied emotions. This descriptive evidence begs the question of the functions of embarrassment, which I examine in the second half of the paper. In the second half of the talk I review two studies that are consistent with an appeasement account of embarrassment: embarrassment shapes social interactions, namely teasing, that have appeasement functions, and individual differences in the relative absence of embarrassment are related to poor psychological adjustment. I conclude by discussing the implications the study of embarrassment has for a general understanding of the social functions of emotion.

Age Preferences In Mates In Homosexuals And Heterosexuals: Evidence Of Evolved Modular Mechanisms?

Douglas T. Kenrick

Will report on a consistent life history pattern of mate choice found in males and females across a number of modern societies and data collection methods. More recently, data collected from over 2,000 marriages during the 17th and 18th century in the Netherlands yields the same pattern. Young males express interest in women their age and older, men in their twenties express interest in older and younger women, and older men express interest in younger women. Women at all ages express an interest in men their age or older. Data from 783 homosexual advertisements reveal the same lifespan pattern in homosexual as in heterosexual males, and a slightly different pattern in homosexual versus heterosexual females. Results are discussed in context of more recent survey data and previous literature to suggest that homosexual preferences may reflect on conceptions of independently evolved and specialized psychological mechanisms.

Dominance And Heterosexual Attraction

Douglas T. Kenrick, Stephanie Brown, and Alicia Barr

In previous research conducted with Ed Sadalla, we found evidence that nonverbal expressions of dominance enhanced the sexual attractiveness of male targets, but had no influence on the attractiveness of female targets. The complete lack of effects for female dominance was surprising to some. Given findings that female primates will often refuse copulations with males that are below them in the dominance hierarchy, we conducted two new studies to test the hypothesis that female dominance would be unattractive to males if the female was directly dominant over the male judge. In study 1, males and females judged targets who were described as working for the same organization, and who varied in being either directly above the subject, directly below the subject, or a peer of the subject. In this study, female dominance did affect male judgments ­ males expressed least attraction towards females directly above them, and most attraction towards females directly below them. Contrary to previous results, however, male dominance did not affect female judgments. A second study varied whether the targets were high or low dominance in the subject's own organization or in another organization. In judging men in other organizations, females again showed a preference for dominance in males. In light of other findings suggesting that dominance has differential attractiveness value depending on whether the dominance is expressed within or outside the relationship, a more complex model of the dominance­attraction relationship is proposed.

Fertility Reduction As A Lineage Survival Strategy In The Face Of Recurrent Demographic Bottlenecks

Karen Kessler and James L. Boone

Human Evolutionary Ecology Program, Anthropology Dept., University of New Mexico

We present a model that demonstrates that lower than expected fertility of humans can be explained as a strategy to maximize longterm fitness in the face of periodic calamities that result in demographic bottlenecks. There are three conditions that must be met for this model to be plausible: 1) population history is characterized by periods of growth punctuated by recurrent crashes caused by calamities such as climatically induced resource shortfalls; 2) a strategy is available to individuals which increases the probability of survival through a bottleneck, but which in order to implement, requires diverting resources away from producing more offspring; and 3) longterm fitness benefits to increased survivorship through a crisis must outweigh or equal the fitness benefits that would accrue to putting the same resources into higher fertility. We present a formal mathematical model that shows that relatively slight increases in survivorship can outweigh the benefits of higher fertility in the long run even if crises are neither very frequent nor particularly severe. The model employs three key variables: r (intrinsic rate of growth), p (probability of a crash occuring during time t), and S (severity of the crash, measured by proportion of the population surviving the crash).

The role of emotion in guiding behavior across the cost­benefit landscape

of the social environment

Timothy Ketelaar

NIMH Postdoctoral Training Program in Emotion Research

Department of Psychology

University of Illinois, Champaign, IL 61820

Several evolutionary perspectives have converged on a general view of emotions as psychological mechanisms designed to solve the adaptive problem of representing the cost­benefit structure of one's social environment (Frank, 1988; Nesse, 1990; Tooby & Cosmides, 1990). Some models focus on the manner in which particular fitness­relevant circumstances come to elicit adaptively­patterned emotional representations of one's social environment (Nesse, 1990; Nesse & Williams, 1995). Other models focus on the strategic effects that these emotions have on subsequent cognition and behavior in a social setting (Frank, 1988). In four experiments, several basic premises of these models are explored. First, the general role of positive and negative moods in representing costs and benefits is explored by examining participant's emotional reactions to actual changes in important resources. Evidence is then presented from several laboratory experiments which explore the role of a particular negative emotion­­guilt­­in facilitating cooperative behavior in a social dilemma known as the Prisoner's Dilemma.

Butch or Femme: Partner Preferences of Gay Men and Lesbians

Peggy Kim and Michael Bailey

Department of Psychology, Northwestern University, Evanston, IL 60208­2710

pkim@merle.acns.nwu.edu

Homosexual people differ markedly in the extent to which their behavior is stereotypically masculine or feminine. This variation is sufficiently salient, for example, that both gay men and lesbians have invented a vocabulary to classify individuals according to their degree of gender nonconformity. In a series of studies we examined the importance that gay men and lesbians attach to a potential romantic partner's behavioral gender nonconformity. Gay men were markedly prejudiced against effeminate men. Lesbians' preferences were much more variable. These results have implications for the meaning, and explanations, of sexual orientation.

Sex Differences in Sexual Jealousy: Testing Two Competing Hypotheses

Lee A. Kirkpatrick

Psychology, College of William & Mary

Williamsburg, VA 23187­8795

WPSSLAK@WMMVS.CC.WM.EDU

David M. Buss

Psychology, University of Michigan

Ann Arbor, MI 48109­1346

DBUSS@UMICH.EDU

Different adaptive problems faced by men and women over human evolutionary history ­­ paternity uncertainty for men and commitment/resource diversion for women ­­ have led evolutionary psychologists to predict and empirically demonstrate sex differences in the weighting given to cues that trigger jealousy. According to a recently­proposed alternative hypothesis, these findings can instead be explained by socialized sex differences in beliefs about the respective conditional probabilities relating sexual and emotional infidelity (i.e., the perceived likelihood that one has occurred given that the other is known to have occurred). In two separate studies (N's = 1122 and 234), we pitted this "double­shot hypothesis" against the evolutionary hypothesis using a variety of different research strategies. In every case, the evolutionary hypothesis was supported and the double­shot hypothesis falsified. Specifically, sex differences remained even when the potential effects of differential conditional probabilities (and thus the double­shot effect) were eliminated by (a) rendering the two infidelity types mutually exclusive; (b) asking respondents which aspect was more upsetting when both were presumed to have occurred; and (c) statistically controlling differences in beliefs about conditional probabilities in logistic regressions.

Ritual/Speech Co­Evolution: A Darwinian Account Of "The Human

Revolution".

Chris Knight

Dept. of Anthropology and Sociology, University of East

London, Longbridge Rd., Dagenham, Essex RM8 2AS, England

email: C.Knight@uel.ac.uk

Studies of the energetics of hominid encephalisation suggest that human females in kin­based coalitions balanced their energy budgets by increasingly exploiting the muscle­power of males as mates. A coalitionary strategy of compelling males to bring meat "home", on pain of exclusion from sexual relations, would generate anomalously high levels of ingroup co­ operation. In view of the costs of deception, very high levels of ingroup trust and co­operation would have to be established before there would be selection pressures favouring reliance on a purely conventional system of communication, such as speech.

Signals indicating "No sex" to outgroup males would be predicted to encounter high levels of listener­resistance. We would expect these signals to be negative counterparts of the standard signals of female "courtship ritual". This yields, instead of "RIGHT sex/species/time", "WRONG sex/species/time". Costly ritual signals of this kind, directed externally, would generate intense ingroup solidarity, sufficient to underwrite internal reliance on conventional signals. Any conventional vocal label attached to the displaced construct "WRONG sex/species/time" now qualifies as a word. In uttering it, joint attention is focused outside personal space and time. To

specify intended meaning, the speaker must now draw the listener's attention from the abstract to the concrete, from "the gods" to "the mortals", accounting for the structural novelties of syntactical speech.

MENTAL LIFE AS A SMALL­GROUP PROCESS

Ferdinand Knobloch, M.D.,F.R.C.P. (C.)

Professor Em. of Psychiatry, University of Brtitish Columbia,Vancouver,Canada

­­­­­­

The author, a psychotherapist studying therapeutic communities from ethological point of view, replaced Freud's and others' one­person­models withthe small social group model as the minumum system for studying an individual. The concept of "group schema" was introduced (Knobloch, 1963), which anticipates later concepts such as Bowlby's "working model".In connection with evolutionary studies (such as Harlow's affectional systems;Cosmides' hypothesis of social exchange as a Darwinian algorithm; individual versus group selection controversy), the following hypotheses will be discussed: Group schemas are genetically programmed, though individualized in ontogenesis; psychopathology of social exchange is the most common problem in psychotherapy; fantasy and dreams are"idling" processes (K.Lorenz) in group schema; the axis of esthetic experience is locomotion in one's group schema; "group schema" may contribute to the understanding of the religious and other experiences of the presence of supernatural beings; social exchange is the basis of distributive and retributive justice, and may be source of the belief in the world justice (Lerner), as well as a neglected factor in the developmental theories of human society. Also, a third solution in the individual (Dawkins,etc.) and group (D.S. Wison & Sober) selection controversy for some socially important characteristics (such as altruism/egoism) will be suggested.

What is the function of serotonin in emotion regulation?

Brian Knutson, Ph.D.

Bowling Green State University

Department of Psychology

Bowling Green OH 43402

Forebrain serotonergic neuroanatomy exhibits remarkable conservation across the phylogeny of mammalian species. Recent evidence indicates that these projections may also show conservation in their functional implications for emotion regulation. Original research is presented on the emotional effects of serotonergic manipulations on both rats and humans. In rats, serotonin depletion can intensify fear behaviors in ethological paradigms (i.e., open field, elevated plus maze), as well as enhancing aggressive behaviors (e.g., muricide, intruder aggression). Further, serotonin depletion magnifies dominance asymmetries in the social play of juvenile rats. In humans, serotonergic augmentation via a four­week administration of a selective serotonin reuptake inhibitor (SSRI) diminished focal reports of hostility and global reports of negative affect at both one­ and four­week assessments. Additionally, this treatment increased affiliative behavior in a dyadic puzzle­solving task. These data on normal rats and humans suggest that serotonin plays a role in the regulation of negative emotions. These findings also argue for the utility of simultaneous consideration of neural, phenomenological, and behavioral levels of analysis in assessing the social function of emotions.

Retrieval Cues in Social Categorization: Content and Context Effects

Robert Kurzban*, John Tooby, & Leda Cosmides

Center for Evolutionary Psychology ­ University of California Santa Barbara

Santa Barbara, CA 93106

kurzban@psych.ucsb.edu, tooby@alishaw.ucsb.edu, cosmides@psych.ucsb.edu

We have proposed that complex psychological adaptations exist for parsing the social world into relevant categories, and that these adaptations exist by virtue of selection pressures relating to the complexities of alliance formation, intergroup conflict, and interpersonal coordination. In particular, we suggest that humans can and will use a variety of cues from the social world to extract information about the composition of the relevant cooperative groups in the environment. Additionally, because the impact of participating in and discerning the composition of coalitions differed for men and women, we expect that the way in which social targets are encoded varies with the sex of the observer and of the targets. Finally, we suggest that although a target's race constitutes a powerful cue for categorization, the extent to which it is used as a retrieval cue can be attenuated under appropriate conditions. In a series of experiments, we examined the extent to which conversational pragmatics, race, sex, and clothing color were used by participants in retrieving information about social targets. Results are consistent with the idea that the degree to which a particular cue is used is a function of that cue's diagnosticity of coalition membership and the availability of other diagnostic cues. Support for the expected mediating effect of observer and target sex was also obtained.

The Biosocioeconomic Circuitry of the Mind and the Generation of Psychological, Behavioral, and Social Phenomena

Peggy La Cerra

Santa Barbara, California

A conceptual model detailing the major functional components of the primary decision­making circuitry of the human mind is presented. This neural complex performs on­line cost­benefit analyses of factors comprising an individual's current "biosocioeconomic world", generates mental models of immediately prospective biosocioeconomic worlds, performs comparative analyses across working models, and generates "optimal" psychological, physiological, and behavioral outputs on a continual basis. As the central mechanism orchestrating our negotiations in the social world, it is also a core component of the neuroendocrinological circuitry that directs all human life activities in a gender­specific, lifestage­dependent manner. The biosocioeconomic­negotiation parameters and information­processing tendencies of the system (one's "personality" and "cognitive style") calibrate during the first few years of life in response to various intra and extrauterine environmental factors. The system's "behavioral optimization standards" change at the onset of each new lifestage. In addition, the system finely calibrates in response to behavioral outcomes thereby "learning" throughout the lifespan. This model provides a mechanism for the generation of "normal" and "abnormal" human mental experiences and behaviors, as well as myriad social, cultural, political, and economic phenomena; furthermore, it provides a cogent explanation for the psychological and behavioral uniqueness of individuals arising from a universal biological substrate.

Bobbi Low

EVOLUTIONARY SEX DIFFERENCES IN HIRING APPLICANTS

Marc Luxen

Tilburg University, Psychology Department

P.O. Box 90153

5000 LE Tilburg The Netherlands

Predictions derived form evolutionary psychology about sex differences in the selection of applicants were tested. Fifty­seven male and 52 female undergraduate students indicated on a ten­point scale the likelihood that they would hire each of 32 applicants, represented by a photograph and a short personality description. The photographs differed in two levels of attractiveness (low or high), the descriptions in two levels of conscientiousness, dominance and agreeableness, presumaly triggering evolutionary mechanisms of mate choice, intrasexual competition, and selection of coalition partners. As predicted, women valued agreeableness more than men. Women showed a preferences for low attractive women and highly attractive men, whereas men preferred attractiveness in both sexes. Predictions concerning dominance and conscientiousness were not confirmed. It was concluded that the domain of application of evolution theory extends beyond the behaviors and mechanisms typically studied in evolutionary psychology

Infectious Agents And Hormones: Implications For Evolutionary Medicine

Mark Lyte

Department of Biological Sciences

Mankato State University

Mankato, MN 56002

Recent studies have demonstrated that infectious agents can actively respond to the neuroendocrine hormones present within humans. For example, exposure to the catecholamine norepinephrine, which is one of the principal human stress hormones, can increase the growth of pathogenic bacteria over 100,000­fold as well as increase the expression of virulence­associated factors such as toxins. The evolution of unicellular organisms preceded that of vertebrates such as man. A wide spectrum of hormone­like materials and their respective receptors have been recognized in microorganisms for years. The presence of such hormones in microorganisms is believed to represent a form of intercellular communication and as such may constitute a type of primitive nervous system. In the case of norepinephrine, it is perhaps somewhat surprising to learn that the presence of what is thought to be almost exclusively a vertebrate neurotransmitter is in fact widely dispersed throughout nature. In addition to its presence in vertebrates, norepinephrine has been additionally identified in plants, insects and fish. This ubiquitous distribution of a neuroendocrine hormone suggests that microorganisms in general have had ample time preceding the evolution of man to come into contact with a spectrum of neuroendocrine hormones and develop mechanisms by which to synthesize as well as recognize hormones. It is therefore suggested that neuroendocrine hormones might serve as a type of environmental cue by which microorganisms may sense their surroundings upon entering a human host and thereby initiate pathogenic processes. As such, the study of the interaction of infectious agents with neuroendocrine hormones may have important implications for evolutionary medicine. Chief among these would be the consideration whether the ability to cause disease in man represents a reflection of a particular microorganism's evolutionary exposure and adaptation to its environment which happens to contain a particular set of neuroendocrine hormones that are also found in man.

Creating Evolutionarily Significant Groups: Judaism As A Case Study

Kevin MacDonald

Department of Psychology, California State University­Long Beach

Long Beach, CA 90840­0901

kmacd@csulb.edu

Humans are able to form group­structured populations in which the group becomes the vehicle of selection. This paper will discuss several processes critical to the group structure of traditional Judaism: 1) High levels of within­ group genetic commonality achieved by endomagous matings and resistance to genetic assimilation with surrounding people; 2) Social controls that raise the cost of defection and non­compliance with group goals by penalizing not only the individual but also blood relatives; 3) Intensive mechanisms of group enculturation (indoctrination) directed at producing within­group altruism and economic cooperation as well as conformity to other group goals, such as maintaining genetic and cultural separation from surrounding peoples. Based on the social science literature on indoctrination and social identity processes, a model will be presented in which indoctrinability is conceptualized as an individual differences dimension with genetic and environmental sources of variance. Over historical time average group standing on the trait of indoctrinability is expected to increase because individuals low on indoctrinability are more likely to voluntarily defect or be forcibly excluded from the group. Historical evidence will be provided that in fact non­conformists have excluded themselves or been excluded by Jewish groups. Group processes may therefore result in feed­forward effects which result in shaping psychological mechanisms that facilitate the development of cohesive groups.(218 words)

Life History and Human Development: Alternate Strategies Versus Heritable Variation

Kevin MacDonald

Department of Psychology

California State University­Long Beach

Long Beach, CA 90840­0901 KMACD@CSULB.EDU

I argue on theoretical and empirical grounds that the most parsimonious interpretation of the available evidence is that differing human life history strategies do not represent alternate strategies triggered by environmental cues of resource availability. Variation in life history strategies is here conceptualized as influenced primarily by genetic variation in viable reproductive strategies. In addition to evidence of the heritability of variables related to reproductive strategies, data are reviewed indicating that a wide variety of stressors result in delayed physical maturation, including the onset of menarche, while better nutrition and lack of stress result in more rapid physical maturation and earlier onset of menarche. Historical data are reviewed indicating that the primary response of Western populations to resource scarcity has been to delay marriage and restrict reproduction. However, since 1965 there has been a dramatic rise in low­investment parenting in the United States associated with a decline in traditional cultural supports for high­investment parenting and interpreted here as occurring primarily among individuals genetically inclined to low­investment parenting. These secular trends are analyzed in terms of changes in the social (group) control of reproduction.

Sexual Media And Gender Differences: The Value Of Evolutionary Theory

Neil M. Malamuth

University of California, Los Angeles

Evolutionary psychology theory is used to explain sex differences in uses of and gratifications derived from various types of sexual media. These differences are viewed as at least partly due to gender dimorphism in sexuality mechanisms that evolved in ancestral environments in response to the contrasting adaptive problems faced by women and men. Uncanny correspondence is revealed between the specific content of these ancestral adaptive problems and the content of modern formulas used in sexual media. Moreover, data across a variety of studies and responses are shown to fit a meaningful pattern predicted by the evolutionary model proposed. Using the evolutionary paradigm, a comparison is made with explanations based only on differences in socialization that do not include gender dimorphism in sexuality mechanisms.

Archetypes in the Evolved Mind: Preference Rating of Images Representing

Archetypal Themes.

Alan Maloney

Department of Psychiatry and Behavioral Sciences

Stanford University School of Medicine

Evolutionary, psychologic and linguistic research has shown the human mind to be a priori structured. Although most theories of the mind can not account for these results, they are consistent with archetype theory of analytic psychology. As part of a research program to integrate contemporary experimental results with psychologic theory, I asked subjects to rate their preferences for images representing archetypal themes and factor analyzed their responses. The results are consistent with the hypothesis that archetypal themes determine affective responses. Archetype theory may prove itself to be useful in operationalizing certain modern­day theories of evolved mental structures.

Raisins Of State

Mary Maxwell

Author of Morality among Nations

Address: GPO Box 1824 ADELAIDE SA 5001 Australia

Home Fax: 011­61­8­379­3401 Tel: 011­61­8­379­1735

Henry Kissinger says, in Diplomacy (1993), that the US should not be confrontationist with China (such as in regarding Taiwan) because of raison d'etat. This French­named theory (related to 'national interest' and realpolitik) sounds neat, but it isn't. It is a wholly inadequate intellectual construct (more suited to the name I have given it above: raisins of state). What has this to do with human evolution? The false simplicity of treating nations as unified actors is agreeable to our emotional reactions ­­ we see our own group and its leader as a unit, and project the same unity onto 'the enemy'. In doing so today we blot out much of reality. Raison d'etat has no capacity to deal with the new global economic power of non­state actors, much less with the ecological crisis. Moreover, as Sidney Blumenthal notes, the theory of the national interest does not even concede that it needs to look at the interests of the majority of the people within the nation! This paper will offer ways to get past our evolved obstacles to global thinking.

Testosterone and Dominance in Men

Allan Mazur

Public Affairs Program, Syracuse University

tel: +1­315­445­1970

fax: +1­315­443­5451

e­mail: amazur@forbin.syr.edu

In men, high levels of endogenous testosterone (T) seem to encourage behavior apparently intended to dominate ­­ to enhance one's status over ­­ other people. Sometimes dominant behavior is aggressive, its apparent intent being to inflict harm on another person, but often dominance is expressed nonaggressively. Sometimes dominant behavior takes the form of antisocial behavior, including rebellion against authority and law breaking. Measurement of T at a single point in time, presumably indicative of a man's basal T level, predicts many of these dominant or antisocial behaviors. T not only affects behavior but also responds to it. The act of competing for dominant status affects male T levels in two ways. First, T rises in the face of a challenge, as if it were an anticipatory response to impending competition. Second, after the competition, T rises in winners and declines in losers. Thus, there is a reciprocity between T and dominance behavior, each affecting the other. I contrast a reciprocal model, in which T level is variablle, acting as both a cause and effect of behavior, with a basal model, in which T level is assumed to be a persistent trait that influences behavior. An unusual data set on Air Force veterans, in which data were collected four times over a decade, enables us to compare the basal and reciprocal models as explanations for the relatinship between T and divorce.

Sex And Laterality Biases In The Concern Of Second­Degree Relatives

Donald H. McBurney, Steven Gaulin, and Stephanie Brakeman

Department of Psychology and Department of Anthropology

University of Pittsburgh, Pittsburgh, PA 15260

Evolutionary theory yields predictions about how individuals should distribute their investment in kin. In particular, sex biases in parental confidence and in the variance in male and female reproductive success suggest particular biases in investment tactics. Predicted biases in 1) sex of investor, 2) sex of target, and 3) laterality of the relationship (matri­ vs. patrilateral) are all examined in the context of a contemporary North American sample of second­degree relatives (aunts/uncles/nieces/nephews) where it is possible to control for factors affecting opportunity to invest. There are some surprising results. For example, despite strong patrilineal elements in American society there is a marked matrilateral bias in the concern of uncles and aunts.

Stirring the Gene Pool: Maintenance and Expression of Diversity

Carol A. McMillan

Wenatchee Valley College, Omak Campus

Omak, Washington 98841

email: cmcmilla@ctc.ctc.edu

(509) 826­7414

An important similarity between rhesus monkeys (Macaca mulatta) and humans (Homo sapiens sapiens) is their tenacity in adapting and surviving in multiple environments. In species such as ours, mechanisms must be in place for introducing and maintaining diverse alleles in breeding populations. In the free­ranging rhesus monkey population at Cayo Santiago, two mechanisms exist that meet these ultimate needs. First, a lineage­specific mating system acts to concentrate novel alleles, increasing the probability of their expression in a subpopulation. Second, adjustments in mating length and visibility nullify the effects of male dominance rank, allowing most fully adult males to mate successfully. This mechanism acts to retain in the gene pool any alleles that are sufficient for an individual to reach maturity. If wild rhesus monkeys also employ these two mechanisms for maximizing polymorphism, then we can see how the species has become genetically equipped for survival in diverse conditions.

The Role Of Self­Deception In Cooperation And Competition

Jeffrey McNally & Michele K. Surbey

Mount Allison University, Sackville, N.B., Canada, E0A 3C0

Deception and self­deception may be two psychological capacities serving to enhance an individual's inclusive fitness. Self­deception has been defined as any psychological act in which one thought or belief is held at the expense of another (Gur & Sackheim, 1979). The present study was designed to test the notion that we may deceive ourselves about our own intentions or the intentions of others (Nesse & Lloyd, 1992) in situations which allow us to cooperate with others, if the cooperative behaviour has the potential to improve fitness. We may also deceive ourselves in situations where we may need to compete with others (Trivers, 1985), if not competing might represent a loss of fitness. The Self­Deception Questionnaire was administered to 80 women and 70 men in a university setting to determine their levels of self­deception. A series of vignettes, conforming to the Prisoner's Dilemma Game format, were administered in questionnaire material to measure participants' tendencies to cooperate or compete in three different contexts (family, mating, and neutral). Results indicated that participants were significantly more likely to cooperate with kin than with non­kin, p < .0001, and that, overall, men were significantly less cooperative than women, p < .014. Moreover, participants scoring highly in self­deception cooperated more in both family and mating contexts than those with low scores in self­deception, p < .05. Finally, the three­way interaction between sex, context, and level of self­deception indicated that the role of self­deception in cooperation and competition may vary according to the sex of the individual and the context.

Kinship: The Tie(s) That Bind(s)

Linda Mealey

Psychology Department

University of Queensland

Brisbane, 4072 Australia

Until recently, sociobiologists and behavior geneticists have been at best, ignorant of each other's work and, at worst, antagonistic. This is largely because sociobiologists emphasize the study of pan­specific behaviors and mean effects, while behavior geneticists focus on individual differences and variability. Thus, what has traditionally been grist for one has been chaff for the other. At the core of both disciplines however, is the same fundamental concept­­ kinship. As the study of the biological bases of social behavior, sociobiology concerns itself with the adaptive value of mating, parenting, and other kin interactions; behavior genetics, on the other hand, relies on kin and kinship structures as a methodological tool. The purpose of the current presentation is to show that there is much room for collaboration between the two disciplines­ for example, in the study of assortative mating, parent­offspring conflict, sibling rivalry, and even the proximate triggers of various facultative developmental strategies.

Fertility and a Mate's Signals of Continued Presence

Edward M. Miller

Professor of Economics and Finance

University of New Orleans

New Orleans, LA 70148

504­286­6913 (work)

504­286­6397 (fax)

504­283­3536 (home)

emmef@uno.edu (E­Mail)

A well designed human female would have one or more devices for detecting a committed male, and increasing her fertility in his presence. The evidence that the menstrual cycle is more often of a fertile type when there is regular sex, that sex promotes the success of the GIFT procedure, that an extract from male sweat affects the female cycle so as to promote fertility, that exposure to men influences ovulation, suggest that females do have such devices. Much human sexual behavior and anatomy, including non­reproductive sex, the presence of a functional vomeronasal organ, axillary hairs, and the apparent design of the axillary for emitting odors or pheromones, the desire to cuddle, the male tendency to fall asleep after intercourse, the thickness of the human penis, may be part of a system by which males send and females receive evidence of the males continued presence.

Males may be "tamed" by pheromones emitted by females and led to adopt a less risk taking life style, more characteristic of "married men" than of single men. In both sexes, pheromones may contribute to the recognition of the existence of a pair bond and to its maintenance.

Evolutionary Epochs in Neural Evolution: A Model and Some Implications for Human Psychological Functioning

Michael E. Mills

Psychology Department

Loyola Marymount University

Los Angeles, CA 90045

email: memills@gmail.com

This paper offers a cross­species model of the accretion of macro neurological functional systems, and their putative functioning in modern humans. The implications of this model to understand both normal and dysfunctional human psychological functioning are explored. Main points include: (a) as brains evolved there developed, at various evolutionary epochs, a functional differentiation between several semi­independent, macro regulatory systems in a hierarchic configuration, (b) differential major regulatory system involvement is characteristic of many psychological dysfunctions, and (c) interventions have differential effects on different regulatory systems. Evidence from various research domains, including the evolutionary, neurological and clinical literature, is presented in support of the model. Some implications of the model for research and clinical practice are discussed.

Susan Mineka

The Evolutionary Biology Of Demographic Transition

Ulrich Mueller

University of Marburg (Germany)

The concept of "demographic transition" stands for a uniform dynamical pattern in all societies which have ­ in the process of industrialization and socioeconomic development ­ experienced a decline in mortality rates, followed by a decline in fertility rates, both down from app. 25­50 per 1 000 per year to app. 10 per 1 000 per year. As a consequence of the time lag, there was a phase of rapid population growth in between the two developments. The decline in both rates always started among the urban elite's and reached the rural underclass last. Also, the higher the peak growth rates are before fertility rates start to fall, then, the faster fertility rates will fall. In no society we know of, fertility rates have started to fall before the fall of mortality rates. On no society we know of has the transition started in the poorer classes. The uniformity of this dynamical pattern in various cultures is strong evidence of a common evolutionary biological mechanism behind it. I will give various alternatives evolutionary explanations of demographic transitions and will try to evaluate them with demographic data.

Facial Dominance in Homo Sapiens as Honest Signaling of Male Quality

Ulrich Mueller, Institute of Medical Sociology, Medical School, University of Marburg

tel: +49­6421­286244

fax: +49­6421­285660

e­mail: mueller2@mailer.uni­marburg.de

Allan Mazur, Public Affairs Program, Syracuse University

tel: +1­315­445­1970

fax: +1­315­443­5451

e­mail: amazur@forbin.syr.edu

For a cohort of military officers, graduates of the class of 1950 of the United States Military Academy at West Point, dominant facial appearance was the most important predictor of rank attainment at the academy and ­ for those who graduated from staff college ­ for high final rank. For men performing below the average, however, dominant facial appearance was a handicap for promotion. High rank came with high fitness. Thus, facial dominance can be an evolutionarily stable honest signal of leadership qualities in a male dominance hierarchy. These findings may apply also to civilian populations.

Did The Changes in the Economic Environment of the Patagonian Tehuelche Tribe

(XVI to XIX Centuries) Affect their Marriage System?

Pablo Nepomnaschy

Evolutionary Biology Area, Universidad Nac. de la Patagonia S.J.B, Argentina.

This study investigated the influence of appearance, availability and distribution of European resources on the Tehuelche marriage system. Information was collected from 127 journals from European expeditions between 1520 to 1884. A direct relationship was found between the assimilation of European resources into the Tehuelche culture and the development of a socio ­ economic stratification. Earliest journals mention just a headman with little political power while later journals describe politically powerful chiefs and 5 different social hierarchies (SH). Reference to economic differences between individuals (EDBI) appeared late on the XVII c. In 30 % of the references of EDBI (n = 87), chiefs were referred to as the wealthy individuals.Tehuelches were early described ( XVII c.) as mostly monogamous. An increment in the mention of the practice polygyny was recorded in the XVIII and XIX c. Earlier references to polygyny were associated with high SH males (53 %, n=16), and later ones with wealthy males (63 %; n = 16). These results suggest that the introduction of accumulative goods caused a social and economic stratification of the Tehuelche society. It permitted some males to monopolize resources and, as a result, it allowed them to acquire and economically support more wives.

Varieties of Depressive Experience

Randolph Nesse, M.D.

Department of Psychiatry

The University of Michigan

Ann Arbor, MI 48109­0840

Attempts to specify the functions of low mood have foundered on two shoals: 1) attempting to discover directly the functions of mood, instead of the special situations in which the various aspects of low mood are adaptive, and 2) seeking a single situation to explain all varieties of low mood. Following previous work on anxiety, this paper proposes that the situation of loss of a reproductive resource has shaped a generic capacity for low mood with advantages mediated by cognitive, behavioral, physiological, and motivational mechanisms. This generic response has likely been differentiated by natural selection in a variety of overlapping subtypes with characteristics that more exactly meet the challenges posed by the specific situation depending on the nature and amount and replaceability of the resource lost, its significance to major life strategies, the permanence of the loss, the individual's control over the loss and whether or not it can be recouped. This proposal makes specific predictions about the kinds of mood changes that should attend different kinds of losses and disadvantages that should arise for people whose capacity for negative affect is blocked by SSRIs.

Social Emotions, Reciprocity, and the Prisoner's Dilemma

Randolph M. Nesse

The University of Michigan

nesse@umich.edu

If the four boxes of the Prisoner's dilemma do indeed represent situations that have been recurrent and important over evolutionary history, then natural selection may well have shaped specialized states that increase the ability to cope with these challenges. The emotions of friendship, rejection, suspicion/anger, and anxiety/guilt have characteristics that suggest they were shaped specifically for these situations. This hypothesis is tested by data that show whether they are reliably elicited by these situations, whether people under the influence of these emotions behave in ways that increase fitness in these situations, and whether the fine­grained characteristics of these emotions can be identified as adaptations that match the requirements of the situations. Variations in reciprocity strategies are correlated with the experience of these emotions, with substantial clinical implications.

Depression and anxiety ­ do they affect reproductive success differentially in men and women?

Åsa Nilsonne M.D., Ph. D.

Dept. of Medical Psychology, Karolinska Institute, Stockholm, Sweden and Dept. of Zoology, Stockholm University, Stockholm, Sweden.

Depression and anxiety disorders are common in the general population and affect roughly twice as many women as men, a finding which has prompted a broad range of interpretations. Most hypotheses that have been suggested have focused on proximate causal factors. This study takes an evolutionary view: if depression and anxiety have a differential effect on the reproductive success of men and women, then sexual selection could result in a sexually dimorphic expression of genetic vulnerability.

The hypothesis in the present study was thus that the reproductive success of men would be more compromised by anxiety and/or depression than that of women .

The Swedish Twin Registry was used to provide data on the reproductive status of

20 000 pairs of same­sex twins. Twins who had been hospitalized for depression or anxiety turned out to have a mean of 1.34 children as compared to 1.19 for individuals with no hospitalisation. In female monozygotic twin pairs who were discordant for anxiety /depression the depressed/anxious twin had a mean of 1.5 children as compared to 1.7 for the control twin, whereas for males the depressed/anxious twin had a mean of 1.3 children and the control twin had a mean of 1.2 children.

Being depressed or anxious thus had no negative effect on reproductive success in this population. The hypothesis that depressed/anxious men would be at a greater reproductive disadvantage compared with depressed/anxious women was not supported. In fact, among monozygotic twins the trend was in the opposite direction.

Numinous Perception: Missing Link in a Paradigm of Human Consciousness Origins

Alondra Oubré

Bioanthropology Laboratory

Department of Anthropology

University of Maryland

College Park, MD

(Mailing address: 1081 Alameda De Las Pulgas #112, Belmont, CA 94002)

(415) 266­7474 (415) 286­7526 (aoubre@shaman.com)

The emergence of human consciousness arguably correlated with the canalization of neurobiological substrates for Piagetian­like concrete operations. Rapid encephalization in early Homo was catalyzed by a complex feedback interaction between environmental selection pressures and novel behaviors. Among these behaviors were possibly preconceived imagery required for standardized tool­making and precision overarm throwing at small prey. In this paper, I explore the hypothetical role of nascent numinous perception ­­ not as precursor of religious beliefs but as a unique genre of abstract mentation ­­ in the evolution of human consciousness. Incipient ritual activities postulated to have occurred in Pleistocene hominids could have fostered symbolic thinking, thereby directly or indirectly selecting for encephalization. Homo erectus could have used vocal calls and gestural display acts, in combination, as part of an intricate communicative and cognitive system for conveying information in both mundane and ritual settings. Early hominid ritual activities, mediated partly by genetic mechanisms, could have been driven by a motivation to reconcile the me­thou polarity, or the perceived schism between self and not­self. Inchoate forms of social ritual performed over one mya could have reinforced or amplified certain cognitive transformations used by Pleistocene hominids in instrumental, that is utilitarian, activities.

An "Acoustic­Signature" Model Of Vowel Evolution

Michael J. Owren

Department of Psychology

Reed College

Portland OR 97202

Recent work in bioacoustics has emphasized the importance of cues to individual­ and kinship­related identity in "signature" calls produced by many animal species, including nonhuman primates. Applying the "source­filter" approach to sound production in monkeys and apes, it is proposed that low­pitched, tonal calls may be significantly better­suited to providing such indexical cues that are noisy or high­pitched vocalizations. As the supra­laryngeal vocal tract is relatively inflexible in many primates, harmonically rich calls produced by different individuals should exhibit stable, subtly distinctive spectral characteristics due to intra­species variation in vocal tract size, shape, and tissue properties. Based on field studies of calls from baboons and rhesus monkeys, it is proposed that protohominids routinely uttered vowel­like sounds long before the development of speech. Laboratory tests of pure­tone and formant frequency discrimination in monkeys and humans further indicates that detailed formant­related characteristics in these sounds were likely both functionally important and perceptually salient. Due to changes in facial morphology (probably reflecting dietary factors), shortening of the protohominid vocal tract created selection pressure for lower laryngeal positions to maintain acoustic­signature cues. Laryngeal descent therefore set the stage for development of flexible vocal tract positioning, but was not itself an adaptation for speech.

Learning to Use the Technology of Sociobiology

William R. Page

Center for Psychology and Social Change affiliated with Harvard Medical School

One aspect of HBES' Great Branch of Learning is learning how to put it to use. As with most branches of Science, there is a technology of application. What is it and how is it taught? This presentation will describe it and the teaching of it. People who know how to apply their understanding of human nature from the perspective of sociobiology and evolutionary psychology are very likely to soon be in high demand. What will they find themselves doing as this new profession bursts on the scene?

Experiences in Vermont State government, in Polaroid Corporation, and in public policy development at a local level in Lexington, Massachusetts have demonstrated the social value of the science. Techniques for applying sociobiology have taken shape and have been successfully learned by large groups.

The Kindness of Strangers: Use of Nonverbal Cues to Identify Altruists in Zero­ Acquaintance Situations.

*Boris Palameta & **William M. Brown

*Psychology Dept., University of New­Brunswick, Fredericton, NB, Canada E3B 6E4

e­mail: bpalamet@unb.ca

**Psychology Dept., St.Thomas University, Fredericton, NB, Canada E3B 5G3

Altruism to non­kin may be beneficial if altruists are preferred partners in mutualistic endeavours. Robert Frank's theory of moral sentiments suggests that people use nonverbal cues such as facial expression and tone of voice to identify potential altruists. In our study, subjects (perceivers) viewed brief (~ 1 min.) video recordings of 4 altruist/non­altruist pairs (targets). Targets were selected from among 73 female undergraduates who completed a 56­item altruism scale. An altruist was defined someone whose score was at the 90th percentile or above, while a non­altruist was defined as someone whose score was at the 10th percentile and below. Perceivers (143 female undergraduates) were asked to identify the altruist in each target pair. To control for verbal content, videotapes consisted of targets telling a familiar fairy tale (Little Red Riding Hood). In addition, altruist and non­altruist targets were matched for age, attractiveness, expressiveness, and acting ability. Results support Frank's theory. Perceivers were able to identify altruists with significantly higher than chance accuracy.

Kinship And Ultra­Sociality: Group Selection Or Descendant­Leaving Strategy?

Craig T. Palmer, Department of Anthropology, University of Colorado, Colorado Springs. ctpalmer@excel.uccs.edu

Lyle B. Steadman, Department of Anthropology, Arizona State University

B. Eric Frederickson, Department of Anthropology, University of California, Santa Barbara

Several group selectionists have suggested that the ultra­ sociality of humans has been produced by group selection acting on kinship "groups" such as clans. We present ethnographic examples demonstrating that clans do not form "vehicles of selection". As an alternative to the group selection model, we propose that both the classification of humans into kin categories, and the ultra­sociality of humans, are the result of the most crucial aspect of the human descendant­leaving strategy­­traditions that identify kin and encourage kinship cooperation.(84 words)

Defining Group Boundaries And Searching For Evidence Of Altruism In War: A Case From The Amazon

John Q. Patton

Dept. of Anthropology

UC­Santa Barbara

Santa Barbara, CA 93106

The current debate concerning groups as vehicles for selection brings into sharper focus the need for precise definitions of "group" and empirical methodologies for detecting group boundaries. Both are essential for testing group selection hypotheses within ethnographic settings, particularly in small­scale segmentally organized societies which are thought to represent the social environments of our evolutionary past, and where more often than not, coalitional boundaries and membership are volatile, and power is decentralized.

A methodology for empirically defining coalitional boundaries is presented. Based on de Waal's concept of triangular awareness, informant judgments concerning the formation of minimal coalitional pairs were used to tabulate alliance strengths and the degree to which men living in Conambo, a small­scale community in the Ecuadorian Amazon, share common patterns of alliance.

Individual risk­taking in war is commonly cited as indirect evidence for altruism where the benefits of security and the advancement of coalitional goals are described as public goods. Data are presented indicating that warriors are rewarded proportionally to how others perceive their willingness to take risks, questioning the utility of invoking extra­individual motivations in a parsimonious description of war and feuds within and between the confines of group boundaries.

Applying Evolutionary Psychology To Ecological Problems

Dustin Penn

Department of Zoology, University of Florida, Gainesville FL 32601

Our environmental problems are due to human nature: we have been "designed" by natural selection to over­reproduce and to exploit natural resources. Yet, the idea that humans have a nature is still generally resisted by environmental and social scientists. This is a problem because proposals for achieving ecological sustainability are often based on wishful thinking. By offering insight into human nature, evolutionary psychology offers a guide for creating realistic environmental policies. Contrary to what many advocate, evolutionary psychology suggests that appeals that stress how environmental problems adversely affect individual health and psychological well­being will be more effective than those that stress the intrinsic good of the biodiversity. Achieving ecological sustainability will require that people act prudently and evolutionary psychologists can suggest the conditions in which people will reduce their reproduction and consumption. Surprisingly, they suggest that an important social mechanism for enforcing reciprocity among humans is moral coercion and religious condemnation. This "environmental morality" hypothesis provides common ground between secular and spiritual approaches to environmental problems. Ironically, our religious nature may be the chink in our psychological armor that enables us to rebel against our selfish genes.

Patrick Peritore

University of Auckland­­Tamaki Campus

Div. of Arts/ Private Bag 92019

Auckland, New Zealand

fax 011­649­373­7000

p.peritore@auckland.ac.nz

This study utilizes Q­Methodology "survey" of equal samples of powerful and regular men and women, to discover the factoral structure of attitudes about sex and power. The 33 statements in the protocol are drawn from biological literature and are meant to test the extent to which subjects are consciously aware of what Neo­Darwinian evolution postulates as ultimate/ unconscious motivation.

There are three hypotheses regarding the resultant factoral structure: 1. Separation and bifurcation of masculine and feminine ideologies, with unique attitudes toward power; 2. Convergence of attitudes as both sexes rise in social power; 3. The sexes occupy different universes of discourse and so the types are bipolar without reference to power as a factor. Interviews are currently in process.

Ethological and Ethnographic Observations of Courtship

Timothy Perper, PhD, Independent Scholar, Philadelphia

Courtship may be defined as those events leading two people from relative strangerhood to social and sexual intimacy. Extensive (ca. 2000 hrs) ethological and ethnographic field observations of courtship yield sequence data and mate choice criteria for women and men. Courtship involves a temporally patterned sequence of approach, talk, turn, touch, and synchronize. Women often initiate courtship proceptively and actively escalate it, and can describe proceptivity in detail. Men tend to describe only the sexual interaction. Empirically, women choose men for their ability to respond to her signals and their meanings to her. Only sometimes do these choices correspond to standard predictions that women choose wealthy, powerful, or high­status men (the poor have children too). Courtship entails repeated and mutual signal exchange (an "iterated signal exchange system," ISES) and can escalate towards sexual intimacy; stabilize into nonsexual conversation; de­escalate into indifference; or produce rapid changes in emotional tone. An ISES can be characterized mathematically by positing a pair of transfer functions and defining input/output parameters; computer graphic analyses show each observed outcome follows rigorously from the assumptions, greatly assisting categorizing authentic vs. deceptive communication.

Population Genetics and Cultural History.

Richard Pocklington

Behavioural Ecology Research Group, Department of Bioscience,

Simon Fraser University, Vancouver, British Columbia, V5A 1S6, Canada

email: pockling@sfu.ca

As Darwin predicted, (1859) evolutionary trees based on linguistic information are similar to trees constructed from genetic distance measurements (Cavali­Sforza, Piazza, et al. 1988, Cavalli­Sforza, Minch, et al. 1992, Chen, Sokal, et al. 1995). It is as yet unknown to what degree cultural history in areas other than language follows population history. I examined the degree to which the distributions of 47 cultural characteristics paralleled the history of 32 African populations. A multiple regression model based on the Mantel (Mantel 1967, Smouse and Long 1986) matrix correlation test was used to examine the fit of seven cultural dissimilarity matrices to a genetic distance matrix while controlling for geographic proximity. The partial regression of cultural distance on genetic distance was statistically significant for two of the seven sets of characters: social structure and kinship organization. This result supports the hypothesis that over thousands of years, some cultural characteristics were vertically inherited, from parent to offspring, in parallel with genetic lineage's (Sokal, Oden, et al. 1991, Cavalli­Sforza, Menozzi, et al. 1993, Guglielmino, Viganotti, et al. 1995).

Infidelity And Sexual Desirability.

Nicholas Pound

McMaster University

Department of Psychology

Hamilton, Ontario, L8S 4K1

Email: g9426393@mcmail.mcmaster.ca

Men, 18­25 years of age, individually viewed an interactive photo story which depicted events involving a heterosexual couple in a long­term committed relationship. The images were manipulated to create two alternative scenarios for a between­groups experimental design: one in which there was evidence of sexual infidelity on the part of the female, and one in which this evidence was absent. As expected, when the photo story presented images indicative of sexual infidelity the female protagonist's desirability as a partner in a long­term relationship was reduced while her desirability as a partner in a short­term relationship was increased. The status of the male subjects affected their responses to questions about the female protagonist: men who were not currently involved in a relationship rated her as being more sexy. Furthermore, they reported that they were more likely to want to have sex with her, and more likely to try to persuade her if she refused. These findings will be discussed in relation to the competitive aspects of male sexual psychology.

A Sexual Selection Model For The Origins Of Art

Camilla Power

Dept of Anthropology, University College London,

Gower St, WC1E 6BT

e­mail: ucsaccp@ucl.ac.uk

Reproductive costs of archaic Homo sapiens females rose rapidly as brain size expanded in the past 250,000 years. Females enhanced fitness by extracting increased energetic investment from males. Advertisement of imminent fertility signals (primarily menstruation) enabled females acting as

kin­coalitions to attract and retain male support. Competition between female coalitions for available male energy drove elaboration of such 'menstrual' advertising to the point where cosmetics were used to amplify 'imminent fertility' signals. theory of parental investment and sexual selection predicts that to the extent a parent invests in offspring, the parent will be discriminating in mate choice. Female archaic Homo sapiens are predicted to be highly discriminating, the major criterion of selection being male ability to provide resources with sexual access dependent on hunting success. As males were drawn into increasing investment they would become increasingly discriminating. A male needs to locate a fertile female of high reproductive value. Advertisement of imminent fertility is a reliable indicator in this respect. Male choice should drive a female trait for cosmetic display. Ostentatious costliness of display by a female with kin would be a reliable index of kin support for an individual female (cf. Zahavi).

The origins of cosmetic ornament, body paint, dance, menarcheal ritual etc. can be understood as costly advertising to discriminating males: 'invest in me because my children will have extensive kin support and higher fitness'.

Raising offspring without paternal's investment in contemporary Venezuela

Grace Chacon­Puignau, Lya Feldman and Evaristo Caraballo

Departamento de Ciencia y Tecnologia del Comportamiento, Universidad

Simon Bolivar, AP 89000, Sartenejas, Edo. Miranda, Venezuela

Female reproductive strategies were studied comparing those mothers that do count on paternal support from the beginning of the offspring raising period with those that do not (single mothers). Evaluation at the population level revealed that single mothers represented a percentage close to 13% of 1990 birth­registering women. The time of previous relationship before the pregnancy was the sociodemographical variable most consistently related to the probability of becoming a single mother, even when considering educational and occupational levels. Women who have a child resulting from sexual relations within a partnership with less than 3 months marry their partners or begin cohabiting without marriage in less than 5% of the cases. Although ages at child birth were similar, single mothers were older when their relationship first started. Semistructured interviews exploring partner selection criteria, sociosexuality, family environment during childhood, attachment styles and reproductive effort, evidenced that single mothers had more probably one­night­stand sexual partners and more boyfriends during adolescence. Diversity of female reproductive strategies and socioecological conditions are discussed.

Premenstrual Syndrome: an Evolutionary Perspective

Chris Reiber

Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA 15261

Although Premenstrual Syndrome (PMS) has long been a focus of medical research, little understanding of the syndrome has been gained through traditional paths of inquiry. The research explores the possibility that an evolutionary approach can yield insights critical to making progress in understanding PMS. First, evolutionary theory suggests particular operational structures for the independent variables that are informative in exploring PMS. Second, it suggests an entirely different vantage point from which to view cyclic changes in women. While traditional medical models of PMS assume that symptoms result from some malfunction or negative force, facultative evolutionary theorizing allows that premenstrual symptoms a) might be adaptive, and/or b) might be the result of the withdrawal of adaptive improvements during other phases of the cycle. These possibilities are explored using correlation analyses between both traditionally­ and evolutionarily­ operationalized independent variables, and multiple measures of symptom change across the cycle.

Recessive X­Linkage Effects on Spatial Test Performance

Pareskevi V. Rekkas and Irwin Silverman

York University, 4700 Keele St., Toronto, Ontario, M3J 1P3

Sex differences favoring males in spatial tests have been well established, with considerable data pointing to the contribution of genetic factors. The question of whether genetic effects are based on X­linkage, however, has yielded inconsistent and sometimes contradictory data. In an attempt to resolve this ambiguity, the present study investigated whether the familial correlational pattern suggestive of X­linkage would occur for 3­ dimensional but not 2­dimensional spatial tests, based on prior reports that the former show larger and more reliable sex differences and hormonal influences. Evidence of X­linkage was not demonstrated for either test type; in fact, the largest correlations were between fathers and sons, for whom a zero relationship was expected. Another unexpected trend was that correlations between fathers and offspring of both sexes were higher than counterpart relationships for mothers, which was regarded as indicative of either socialization effects or genomic imprinting.

Are Human Societies Superorganisms?

Peter J. Richerson,Division of Environmental Studies, University of California Davis, 95616, pjricherson@ucdavis.edu

Robert Boyd, Anthropology Department, University of California Los Angeles, 90024 boyd@anthro.sscnet.ucla.edu

Most evolutionary models of culture assume that individuals transmit culture and are the main locus of forces that affect it. Culture is ideas in the heads of individuals. Decision­ making forces are exerted as individual decision­makers make up their minds about which cultural variants to adopt and which to abandon. Several thoughtful critics of this body of theory have pointed out that human groups seem to have attributes, such as the routines of firms, that do not exist in the heads of individuals. Other critics argue that human societies have institutions for collective decision­ making that cannot be reduced to private, individual actions. These proposals are supported by plausible examples, and beg close investigation. How important are collective cultural phenomena relative to their individual level analogs? What is the relationship between individual level phenomena (e.g. individual attitudes) and institutions (e.g. a new law) before, during and after a collective decision is made? What lessons should we draw for the oft rough­and­tumble character of collective decision­making? Recent work by political scientists investigating policy change in modern societies provides a fine­grained analysis of these issues, and, together with ethnographic accounts from simpler societies, suggests that we might think of human societies as very crude superorganisms with real but limited group­level functionality.(217 words)

Touch, Grab Or Hit: The Behavioral Characteristics Of Winning And Losing Children

Richard W. Rodgerson

School of Kinesiology and Leisure Studies, University of Minnesota

E­mail: rodg0003@gold.tc.umn.edu

Research was designed to generate an ethogram of the behavioral attributes associated with winning and losing children within the context of a four player competitive/cooperative game­like situation. Children in grades K­3 were observed playing a game which required both cooperative and competitive behavior in order to obtain a desirable goal. The experimental design is such that in order to view a movie cartoon a child must enlist the aid of two of the other three children in the group, thus forcing the fourth child to become a bystander. Winning and losing was operationalized as obtaining the most or least time viewing the cartoon. Behavioral measures were conceived as lying on a continuum from physically assertive (touching) to physically aggressive (hitting or kicking). Hypotheses were tested relative to the strategies employed by the winning children. Gender differences were also measured.

Beating Your Neighbor to the Berry Patch

Alan R. Rogers

Dept. of Anthropology, University of Utah, Salt Lake City, UT 84112

rogers@anthro.utah.edu

Every summer, my backyard witnesses a conflict between humans and birds, all of whom wish to eat the same strawberries. Those who wait until the berries are ripe eat none, for by then the others have come and gone. All of us eat sour berries or none at all, and none of us are happy about it.

Such interactions appear to be common in nature; they occur whenever several individuals compete for a ripening resource that is destroyed by the first to harvest it. This is an evolutionary game with no stationary solution: there is no evolutionarily stable strategy, so the population must continue to change. Yet when either the number of competitors or the cost of visiting the resource is large, the strategies vary only within a small region with an unstable Nash equilibrium at its center. This unstable equilibrium is then a good description of the population. This behavior has been confirmed both by computer simulation and by classroom experiment.

Effects of Mere Presence of the Opposite Sex on Attitude Judgments

Jim Roney

Committee on Human Development, University of Chicago

Research with non­human species has demonstrated that the mere presence of opposite sex con specifics often produces reliable physiological and behavioral outcomes. This study attempts to extend such research to human psychological processes. Support was found for they hypothesis that adolescent males will report higher valuations of material wealth when in the mere presence of adolescent females. In addition, highly replicable sex differences in attitudes toward money, competitiveness, and altruism were absent in same­sex testing conditions. These results suggest the possibility that typical gender differences on attitude questionnaires are attributable in part to the activation of mate attraction mechanisms in males; such sex differences may be absent in those contexts in which these mechanisms are relatively inactive.

Uniting Individual Variation and Group Differences: Philosophy and Methods

David C. Rowe, Hobart H. Cleveland, and Richard Wiebe

School of Family and Consumer Resources, University of Arizona, Tucson, AZ 85721.

Evolutionary scholars focus their attention on psychological adaptations. In practical terms, the modal or average response in a group corresponds to the adaptation. The biological basis for psychological adaptations is inferred from arguments about design, universality, or phylogenic heritage. However, most biological systems receive modulation from an accumulation of genetic mutations (whether harmful, neutral, or rarely, beneficial); they create individual variation. New quantitative genetic models permit the simultaneous analysis of group means and individual variation. The conceptual basis of these methods will be illustrated. An appealing feature of these quantitative models is that they can check statistically whether group mean differences and individual variation have the same biological determinants. If this test is affirmative, then the extent of genetic difference between groups may be estimated. Application of these quantitative genetic models will be briefly illustrated using survey data on group differences (e.g., sex differences). They provide a direct test in modern populations of whether genetic influences underlie psychological adaptations. They also make a surprising bridge between the evolutionary analysis of adaptations and behavior genetics.

Adaptive Sex Differences In Reasoning About Self Defense

Melissa D. Rutherford, John Tooby and Leda Cosmides

Center for Evolutionary Psychology, University of California at Santa Barbara

Because of both strength differences and reproductive differences, men and women have different optimal strategies in defending themselves against aggressive others. To comply with the wishes of someone issuing a threat is unnecessarily costly if that person is bluffing. Therefore, men have evolved bluff detection mechanisms. However, if the person making the threat is more powerful than the victim, (or belongs to a coalition more powerful than the victim's) then bluffing is unlikely, and calling the bluff is costly. Therefore, the bluff detection mechanisms in men can be deactivated, and women may not have them at all. Conversely, people in relatively vulnerable positions may be more sensitive to double­cross. Furthermore, because women are vulnerable in particular ways owing to reproductive differences, cognitive processes for evaluating relevant dangers have evolved differently.

Who is Afraid of "Biologicizing" Human Affairs?: Gene­brain Conflict Model

of "Biophobia."

Osamu Sakura

Faculty of Business Administration

Yokohama National University (Japan)

Many academic authors, as well laypersons, tend to take unfriendly position against biological analysis of human affairs. One of the reasons is negative impact from the eugenic movements around the WW II. However, more fundamental factors seem to be behind this tendency because we have ALWAYS the same attitudes. In the late 19th century Darwinian evolutionary theory caused the similar stances. More recently, during the late 1970s and early 1980s, a lot of philosophers and social scientists, even some of the biologists, opposed sociobiology among several countries. Evolutionary epistemology and evolutionary ethics have caused comparable responses. These cases suggest that the human beings may have the natural (genetical?) tendency against the application of biological or evolutionary theory to human beings. My hypothesis about this phenomena, "biophobia," put the reason into the conflict between human brains and genes. These two information processors have a great difference on the processing speed: genes need much longer generations to adjust their information, while brains are tuned to shorter time spans. This discrepancy might have favored our brains to produce "virtual" image of "self," which would be unfriendly to "know" the "real" image of our genetical aspects.

Middleborns Are Different: Birth Order and the Psychology of Kinship

Catherine Salmon

McMaster University, Hamilton, Ontario L8S 4K1

g8815958@mcmaster.ca

Effects of birth order on closeness to individuals, the importance of family roles or names to self­identity, reliance in times of need, or the inclination to record family histories were examined in three studies. First and lastborns were more likely than middleborns to: 1) refer to their kinship status or surname in characterizing themselves; 2) nominate their mother as the individual they feel closest to; 3) turn to parents as opposed to siblings for assistance under two different scenarios of distress; 4) compile family histories. These birth order differences will be discussed in relation to possible differences in perceived, or actual, parental investment.

Race

Vincent M Sarich

Professor Emeritus Of Anthropology

University Of California At Berkeley

94720

Why, at the end of the 20th century, should HBESers, as HBESers, concern themselves with race? Let me list the ways. (1) Race is a salient feature of our everyday world; de jure as well as de facto. (2) Human races are real, and attempts to deny this range from the truly heartfelt but misguided to the pathetic to the absurd. (3) Human races are very strongly marked morphologically ­­ perhaps more so than those of any other mammalian species. (4) Human races are young, with most racial variation no older than about 20,000 years. (5) So much variation developing in so short a period of time implies, indeed probably requires, functionality. (5) There is no good reason to think that behavior should somehow be exempt from this pattern of functional variability. (6) Even when differences among racial means for some salient feature of the human condition are relatively small, as they usually will be, statistical reality will exaggerate the effects of those differences at the more visible tails of the distributions involved; and it is the tails, not the means, that drive feelings and policies. (7) Nonetheless, we cannot allow ourselves to continue to act as if the recognition of the reality of group differences should somehow necessitate, or even encourage, the presence of those groups in statutory and administrative law, and public policy. So let us begin with Ernst Mayr's admonition of 1963: "Equality in spite of evident non­identity is a somewhat sophisticated concept and requires a moral stature of which many individuals seem to be incapable." and see just how realistic, sophisticated, and moral we can be in the minefield that is race, while still coming out alive and ahead having traversed it.

Darwinian Themes in Hawthorne's "Rappacini's Daughter"

Judith P. Saunders

Marist College, F202, Poughkeepsie, N.Y. 12601.

Hawthorne's famous 1844 short story depicts a situation in which the struggle to pass on genes becomes conscious and purposeful. Morally indifferent principles of natural selection and differential survival are personified in the character of Dr. Rappacini, who might with some justice be regarded as the Selfish Gene incarnate. His experiment in genetic engineering represents a deliberate attempt to ensure the evolutionary success of his own lineage. His efforts to endow his daughter with a biological advantage are so successful that his descendants would posses the clear potential to become the sole surviving human line. Hawthorne employs this science fiction­like plot to explore ethical and social implications of the evolutionary forces underlying human behavior.

Use of Twin Research Methods in Evolutionary Psychology

Nancy L. Segal

California State University, Department of Psychology, Fullerton, CA 92634, USA

Twin studies have had a significant influence upon theoretical, methodological and applied aspects of research in the behavioral, social and medical sciences. In recent years, twin methods have been included in an increasing number of research programs within these disciplines. However, the potential contributions from twin designs, as well as sibling and adoption studies, for examining hypotheses generated by evolutionary theory have not been fully realized. A series of studies that have used variations of the classic twin design for examining associations between genetic relatedness and social affiliation are described.Some examples include twin studies of cooperation, bereavement and physical proximity. Data from a new research design using unrelated siblings will also be presented.

Adaptation And The Oral Tradition

Michelle Scalise Sugiyama

Center For Evolutionary Psychology, University Of California, Santa Barbara

Sperber argues that the tale "Little Red Riding Hood" is easier to remember than a twenty­digit number because the tale triggers innate classification schemas, while the number does not. This paper attempts to delineate these hypothesized schemas, in part, by situating the story within a rich, pan­cultural tradition of animal lore. This extensive branch of the oral tradition complements ethnographic evidence indicating that the mind contains mechanisms specifically dedicated to processing and storing information about animal behavior. I thus argue that the schemas posited by Sperber consist of the set of cognitive mechanisms dedicated to processing the adaptively relevant information presented in the story. In other words, "Little Red Riding Hood" is easier to remember than a twenty­digit number because the story contains information that the mind has been designed to notice, process, and retain. These findings suggest that the study of narrative might be useful in guiding the formation of hypotheses about the design of the human mind.

Phylogenetic Constraints on Behaviour in Public Places

Katrin Schafer and Klaus Atzwanger

Ludwig­Boltzmann­Institute for Urban Ethology / Humanbiology,

Althanstr 14, A­ 1090 Vienna

e­mail: A8111GCA@vm.univie.ac.at

Evolutionary approaches to environmental aesthetics hypothesize that humans prefer places where exploration is easy and which indicate the availability of resources necessary for survival, e.g. water and food, social contacts, and high prospect refuge quality. Thus, in urban environments, the quality of public places could influence human behaviour, depending on whether phylogenetic requirements are met, or not. The structure of public places may induce general wellbeing and consequently the probability of encounters with significant others. The latter is of high importance since game theory predicts the amount of potential future interactions to be responsible for the probability of cooperation.

To find out the impact of public places on behaviour, we observed interactions, collected questionaire data and developed an inventory to quantify the structural features of a place. Our results strongly support our hypothesis. The amount of e.g. plants, symbolic barriers and sitting possibilities correlated with user behaviour: The better the quality of a place the more interactions were observed and the more satisfaction was reported. Graduation in the urban environment covaries with differences in subjective evaluation and behavioral data. The design of public places enriching personal contacts may be a means to fight anonymity and rising criminality in cities.

Women's Choices Of Sperm Donors: So Many Donors, So Little Information

Joanna E. Scheib

Department of Psychology, McMaster University

Hamilton, Ontario, Canada

jescheib@ucdavis.edu

Donor insemination is a type of reproductive technology through which healthy women can achieve pregnancy. Little is known about the information that recipients use to select their sperm donors, however the results from both experimental and clinical studies suggest that women are concerned with aspects about the donors, such as their health and character. I report the results of studies that identified the information that recipients used when they chose donors at a fertility clinic. Although there was overlap between the results of these studies and the previous findings, a further experiment was conducted to test for qualitative differences between the recipients at the fertility clinic and experimental subjects who were not in fact recipients. Women's choices of donors are discussed in light of these findings.

Delusional Disorders

David Schlager, M.D.

SUNY Stony Brook; Stony Brook, NY 11794­8101

DSM­IV Delusional Disorder (DD) describes a syndrome in which delusional cognitions are delimited in both form (e.g., plausible but fallacious, incontrovertible, preserved intellect and general function, etc.) and thematic content (e.g., persecutory, jealous, somatic, etc). DD is rare and its cognitive forms unlikely to serve a useful function. At the same time, the delusional themes correspond to specific non­delusional concerns which are well­characterized, universal and which, in turn, bear a recognized connections to challenges of social reciprocity and mating. Persecutory and jealous delusions might then represent disordered forms of such domain­specific adaptations, much like panic disorder has been proposed to represent misfiring of stereotyped responses to imminent suffocation or attack. Such a notion is consistent with repeated failures to demonstrate any defects in general inferential reasoning in DD patients, with the lack of valid nosologic distinction between delusional and non­psychotic disorders of similar content (e.g., obsessive­compulsive), and with anecdotal evidence that DD delusions are more effectively treated with mood/anxiety spectrum drugs than conventional antipsychotic medication. Rare delusional misapprehensions may be consistent with optimal (hyper)sensitivity to important environmental threats or, as evidenced by the high prevalence of DD in deaf and immigrant populations, may represent misfirings evoked by exotic perceptions or environmental cues, respectively.

Cross­Cultural Recognition Of Nonverbal Behavior In Schizophrenia

Karen L. Schmidt 1 and John S. Allen 2

1 Department of Anthropology, U.C. Berkeley, Berkeley CA 94720

schmidt@qal.berkeley.edu

2 Department of Anthropology, University of Auckland, Auckland New Zealand

js.allen@auckland.ac.nz

Evaluators from New Zealand (n=24) were able to recognize the unusual

nonverbal behavior of Papua New Guineans with schizophrenia. Videotaped

interviews were rated for expressiveness (1­7 scale) by evaluators who were

unaware of the diagnostic status of patient (n=6) and matched control

subjects (n=4). Judgments about whether or not subjects appeared strange

or unusual, together with a list of expressions and nonverbal behavior

contributing to those judgments were also collected.

1) New Zealand evaluators were able to recognize affective flattening in the nonverbal behavior of Papua New Guinean subjects with schizophrenia. Expressiveness scores were lower for patient (X=3.61) than for control subjects (X=4.43).

2) Patient subjects were judged strange or unusual in a higher percentage of interview segments than were controls. Evaluators' experience with schizophrenia affected recognition of subject strangeness more than either their sex or self­rating of ability to judge character.

3) Evaluators' judgments of strangeness were based on particular aspects of nonverbal behavior, especially unusual hand movements and lack of facial expression and body movement.

Is Brain Size A Causal Influence On IQ?

P. Thomas Schoenemann

Department of Anthropology, University of California, Berkeley, CA 94720

and the Center for Functional Imaging, Lawrence Berkeley National

Laboratory, Berkeley, CA 94720. E­mail: schoenem@qal.berkeley.edu

Several recent studies using magnetic resonance imaging (MRI) of living brains have consistently shown a substantial (r=~0.4) correlation between brain size and general cognitive performance (IQ). Viewed in an evolutionary context, it would make sense for this relationship to be causal. Hominid brains have tripled in size in the last 3 million years in the face of large and obvious evolutionary costs. The most parsimonious explanation is that larger brained individuals within hominid populations held a statistical advantage in the kinds of abilities tapped by modern general cognitive performance tests. However, Arthur Jensen, writing some years ago, suggested that the causality could be tested directly by looking at within­family relationships between brain size and cognitive performance, arguing that this would eliminate the possibility that either cross­assortative mating and/or major (between­family) environmental effects could have produced the between­family associations observed. In this contribution, I report that the correlation between overall brain size and several tests of cognitive performance for 30 pairs of sisters is consistent with previous recent work for between­family comparisons, BUT ZERO FOR WITHIN­FAMILY comparisons. I will present the details of the work and consider the implications of these findings for our understanding of the evolution of both our brains and our cognitive abilities.

Marital Satisfaction as an Assessment Mechanism of Conjugal Costs and Benefits

Todd K. Shackelford1 and David M. Buss2

The University of Michigan, Department of Psychology

Ann Arbor, MI 48109­1109

E­mail: 1tkshack@umich.edu, 2dbuss@umich.edu

Marital happiness or discontent represent evolved psychological states that track the various costs

and benefits associated with a particular marital alliance. Marital satisfaction, on this account,

facilitates continued investment in the marital alliance. Marital dissatisfaction, in contrast, can

serve the adaptive functions of motivating change in the marriage, conjugal defection, or searching

for a more beneficial arrangement. We tested several hypotheses about the design and functioning

of marital satisfaction as an evolved mechanism that assesses conjugal costs and benefits. 214 individuals (107 men, 107 women) provided information about their own and their spouse's personality, marital conflict, susceptibility to infidelity, and marital satisfaction. Additionally,

couples were interviewed by two interviewers to provide independent assessments of each

partners' personality and mate value. Results suggest that costs associated with partner's

personality, mate value discrepancy, esteem of spouse, mate­guarding tactics, sources of

anger and irritation, and susceptibility to infidelity are predictably associated with marital dissatisfaction.

Did Senescence Slip Through Williams' Net?

Thomas L. Shellberg

Henry Ford Community College

For almost 40 years the Medawar­Williams pleiotropic theory of senescence has dominated evolutionary perspectives on why most organisms deteriorate and therefore die. But the validity of this theory has not been demonstrated, nor do I think it will be. It does not, I think, even begin to explain the neat predictable patterns of aging nor the extreme variations in life span among species and it moreover denies that life span is a trait that was directly, positively selected for (like height or clutch size, for example). And there are other very questionable, assumption required which ought to be reexamined, including the centerpiece suggestion that senescence is largely an incidental coattail effect of genes which cause good effects in youth. The most questionable assumption of all is, I think, the first premise which seems clearly rooted in pre­Hamiltonian individual­selectionist thinking. It is my intent to raise questions about this theory and to suggest a radically different evolutionary perspective on senescence more parsimoniously consistent with Williams' usual assumptions about selection.

Aggressive Fantasies towards Friends, Siblings, & Strangers

Virgil L. Sheets

Department of Psychology

Indiana State University

Terre Haute, IN 47809

Although actual homicides are much more likely to be directed at non­kin than kin relations, whether this reflects differences in the psychological reactions to transgression of kin and non­kin, or differences in the behavioral response to their transgressions is unknown. In an initial study, participants were exposed to vignettes depicting sexual infidelity of their partner with either a sibling, a best friend, or a stranger. Afterwards, participants reported their aggressive fantasies and expectations about their behavior. A content analysis reveals no differences in aggressive fantasy against different categories of transgressors, although men reported that they would ruminate longer about the actions of non­relatives and that it was easier to imagine killing a non­relative in this instance. Men also tended (p<.10) to report that they would show more actual aggression against non­relatives. No significant differences were found for women, but this may be a function of the scenario provided.

Ethnocentrism vs. Pragmatism in the Conduct of Human Affairs

Irwin Silverman and Danielle Case

York University, 4700 Keele St., Toronto, Ontario, M3J 1P3

Current concepts such as van den Berghe's "ethnic nepotism" and Rushton's "genetic similarity theory" maintain that the origin of human group conflict resides in ethnocentrism, which represents the extension of kin selection to extra­familial interactions. Silverman, however, has presented an alternative notion, based on the presumption that natural selection would favor pragmatism and plasticity in the formation of group alliances and would disfavor inflexible

constraints based on genetic relatedness. Silverman's view holds that out­group prejudices serve as rationalizations for inter­group conflicts rather than determinants of these. The present paper explores new data bearing on these contrasting theories. We describe a survey­type study

designed to ascertain the salience of ethnocentric motives when confronted with pragmatic considerations. We also examine, from the perspective of both theories, the historical and direct causes of two of the most violent and genocidal of the so­called, contemporary "ethnic wars".

What An Ugly Barbie Doll: Effect Of Changes In The Size Of Waist­To­Hip Ratio (Whr) And Attractiveness Judgment

Devendra Singh

Department of Psychology

University of Texas, Austin, TX 78712

Studies have shown that both men and women judge female figure drawings with low waist­to­hip ratio (WHR) as more attractive and healthy than similar female drawings with higher WHR. However, in these studies, the lowest WHR size investigated was 0.7 and, therefore, it is not clear whether people would have judged figures with WHR lower than 0.7 as still more attractive. Also, studies on WHR and attractiveness have used stimulus impoverished line­drawings. If WHR indeed is a marker of female attractiveness, this effect should be evident in life­like figures such as Barbie dolls. Two studies were conducted to investigate these issues. In the first study, participants were required to rate seven female line­drawing figures differing only in the size of their WHRs (0.4 through 1.0) for attractiveness, healthiness, and other attributes. Participants also estimated the age of each figure. In the second study, participants rated seven Barbie dolls with altered WHR (0.4 though 1.0) for the same attributes as for the line­drawing figures. Results from the line­drawing figures and the Barbie dolls were strikingly similar: Barbie dolls with the lowest WHR (0.4) and the highest WHR (1.0) were judged to be less attractive and less healthy than Barbie dolls with midrange WHRs. The Barbie doll with 0.4 WHR was, however, judged to be 19­20 years old whereas Barbie dolls with higher WHRs (0.9 and 1.0) were judged to be 32­35 years old. Implications of these findings will be discussed.

Body Fat Distribution And Erotic Identification In Lesbian Women

Devendra Singh

Department of Psychology

University of Texas, Austin, Texas 78712

Lesbian literature contains many references to two types of erotic identifications used by lesbian women: Butch identification is primarily defined by more masculine characteristics and femme by more feminine characteristics. I will present data showing that these erotic identifications are not merely social labels and that butch and femme lesbians significantly differ on various measures. The data will show that age­matched butch lesbians a) have more android fat distribution (higher waist­to­hip ratio), independent of overall body weight b) recall more gender­atypical childhood behavior c) engage in more active sexual practices and d) are less inclined to conceive and give birth. However, butch, femme and heterosexual women do not differ in the degree of body image dissatisfaction, dieting frequency or depressive symptomotology.

Culture And The Evolution Of The Human Mating System

Pouwel Slurink

Philosophy Of Science

Catholic University Of Nijmegen

The Netherlands

In an insightful discussion of the mating system of white­fronted bee­eaters Stephen Emlen et al. (Am. Sci. 83 (1995), 2, 148­157) justifies his choice of this species by noting that it has a mating system that is largely unaffected by culture. This could be interpreted to imply that there is no original human mating system on which culture is superimposed. However, we could also think of a couple of evolutionary forces that both determine our "mating system" and our culture in a mutually amplifying way. In this paper we will try to integrate our knowledge about the evolution of the human mating system and our knowledge about the evolution of culture in the hope of locating causal mechanisms with which both are linked.

Pouwel Slurink

Department of Philosophy

University of Nijmegen

Erasmusplein 1

Postbus 9103

6500 HD Nijmegen

The Netherlands

The Giving of Hostages: Are There Evolutionary Roots to this Ancient Practice?

J. Kenneth Smail

Department of Anthropology, Kenyon College, Gambier, Ohio 43022

In contrast to recent political, scholarly and public misuse of the term, this paper articulates a more accurate definition of the hostage concept. This definition is not only consistent with a broad range of etymological sources but is also in agreement with numerous examples from the historical and anthropological record.

Attention is called to the fact that the giving of hostages as confidence­building "emissaries of trust" incorporates several attributes that might be of interest to contemporary evolutionary theorists. First, hostages are typically the biological kin (children; siblings) of those in power, and function as surrogates for them. Second, hostages are often "altruistic" volunteers, or are at least perceived as such. Third, the giving of hostages is not infrequently reciprocated (i.e. close kin are exchanged). Fourth, the a priori intent of such good­faith exchanges is clearly the reduction of tensions, or "reconciliation" broadly defined. Finally, the continuing presence of hostages has an implicit moral component, deterring future acts of aggression while simultaneously enhancing mutual trust.

A closer examination of the biological and behavioral underpinnings, the historical and anthropological precedents, and the political and psychological efficacy of this ancient idea might prove to be a fruitful area for future empirical and theoretical research.

Natural Selection RevisitedDavid Smillie

Duke University, Dept. of Zoology, Durham, NC 27708

Natural selection theory had its origin in a consideration of ecological and habitat conditions ("nature") selecting those traits that maximized the organism's adaptation to external, extra­specific conditions. With the emergence of an interest in selective conditions operating within the species (Hamilton, Williams, E.O. Wilson) the same traditional paradigm was employed: competitive struggles within the species constitute the conditions which select for traits maximizing the reproductive success of carriers. However, if we consider natural selection in sexually reproducing species there are no lineages which represent a continuing pattern of success. Recombination and outcrossing effectively destroy the phenotypic pattern of a parent by breaking up the whole and mixing genes of two different parents in offspring. It is important to see that this process constitutes, over time, a community of genes, each of which is fit for service in an endless variety of organismic contexts. In this paper I develop these ideas and indicate their significance for individual selection theory.

The Genesis Of Shared Fate

Barb Smuts, Department of Psychology and Department of Anthropology

barbara.smuts@um.cc.umich.edu

Steve Lansing, Department of Anthropology and School of Natural Resources

University of Michigan

slansing@umich.edu

Shared fate (correlated fitness within groups) plays a central role in modern group selection theory. Shared fate is both a cause and a consequence of group selection: Some degree of shared fate must exist for group selection to operate, and as group selection proceeds, shared fate increases. Clearly, however, to avoid circularity, shared fate must initially arise through processes other than group selection. To investigate the nature of such processes, we are developing models in which the environment of "agents" includes both the physical environment as well as other agents. One approach investigates how selection can drive networks of interacting agents to form a structure of functional significance, in which the fitness of each agent depends in part on the state of the entire network of interacting agents with respect to one or more explicitly defined ecological parameters. We call this "system­dependent selection". Two aspects of natural selection are involved: selection for individual agents or "phenotypes" with higher fitness, and system­dependent selection optimizing the frequency distribution of phenotypes with respect to one or more environmental parameters. Mathematical simulations show that system­dependent selection can produce:

1. An increase in mean fitness, which may exceed the fitness of the most fit individual expressed in the initial population.

2. A stable pattern of a mixture of phenotypes.

3. Reduced variance in fitness among phenotypes, which converges towards the mean fitness.

Thus, a positive feedback between organisms and environment appears to be one way in which shared fate can arise. A second approach investigates: (a) how simulated primates inhabiting a patchy environnment may self­organize into groups (creating a metapopulation structure) and (b) how ecology (temporal and spatial variance in food resources) and interactions with conspecifics (within­and between­group feedingcompetition) affect within­ and between­group variance in fitness. Thus, both approaches emphasize the role of ecology in structuring interactions among agents in ways that can lead to shared fate.(319 words)

A Frequency Dependence Model of Cooperative Fishing on Ifaluk Atoll

Richard Sosis

Human Evolutionary Ecology Program

Department of Anthropology

University of New Mexico

Anthropologists have often been concerned with why some individuals engage in cooperative foraging activities even though other group members are able to free ride on their efforts. In order to investigate this free rider problem, empirical data was recently collected on Ifaluk Atoll where males regularly fish cooperatively. The pattern of fish distribution on Ifaluk primarily depends on the amount of fish caught. Distributions of smaller catches are generally biased in favor of canoe owners and males who fish, while larger catches are distributed more equitably among all residents of the atoll. Net caloric returns increase as a function of number of males who fish. Since males who do not fish may receive a portion of the catch, these distribution patterns allow males to free ride on the efforts of other males. Calculations of the expected caloric payoffs will be presented that predict when a male should join a group of fishermen. Tests of the model against empirical data collected on Ifaluk were successful in demonstrating that men choose to fish according to the frequency dependent payoffs they expect to receive. Possible extensions and applications of the model will be addressed following a presentation of the results.

The Evolutionary Significance of Metaphor.

Lyle Steadman, Department of Anthropology, Arizona State University.

E­mail: LyleSteadman@asu.edu

The question addressed is why humans, everywhere apparently, use metaphor, for metaphor is a statement that is literally untrue. What is gained by the lie? It is proposed that the effect of metaphor that has led to its persistence is colusion, collusion between the speaker and listener. Collusion, implying a secret understanding involving deceit, is a form of cooperation. But it is in religion that metaphor achieves apotheosis. As Palmer and I have argued elsewhere, religion is distinguished by at least one individual communicating his acceptance of another's supernatural claim, a claim that cannot be shown to be true. Identifiably, such a claim is accepted as a metaphor. What distinguishes a religious metaphor from other metaphors is the explicit, often passionate, denial that it is metaphor. Such denial promotes a far more intensive collusion than that achieved by an acknowledged metaphor. Examples of such "denied metaphors" include the claim of Roman Catholics that they consume the actual blood and body of Jesus weekly, despite knowing that they originate in the vineyard and bakery, and Australian Aborigines claiming that they are actually kangaroos, without ever attempting to mate with one or resist their slaughter, as they surely would were a fellow clansman so treated. It is proposed that the reproductive benefits achieved through collusion have led to a selection for the use of both normal and religious metaphor.

Evolutionary Metaphysics

Artur Stern

Institute BION ­­ for Bioelectromagnetics and New Biology

Celovska 264

1000 Ljubljana

Slovenia

If 'metaphysical' means 'something beyond physical detectability and thorough logical understanding', then inclusive fitness and its fundament ­­ genetical relatedness, the two key­notions of modern evolutionary theory, are essentially metaphysical. To regard two copies of DNA as being 'identical by descent', just two facts are needed: their exact likeness in the nucleotide sequence, and the existence (present or past) of a common ancestor. But when we do not possess the hard proof of the latter ­­ which is almost always the case in life outside the laboratory ­­ we can never detect who is related to whom (although we can, of course, tell who is not). The argument will be extended further to the very concept of the gene, showing that it, too, is metaphysical. In a certain sense genes can thus be viewed as no better than memes: entities with a highly dubious intrinsic power for self­replication. There is, however, a quantum concept of the gene, which can be applied in the project of resurrection of the gene as a general conception. Implications of these findings and statements for human consciousness and behavior will be discussed.

Physical Size Predicts High Female Fertility In A Us Population.

David C. Steven and Henry C. Harpending

Department of Anthropology, The Pennsylvania State University

Physical size and obesity are under the influence of both genes and developmental environment. This paper investigates the temporal relationship between body size and fertility.

Results are presented from a longitudinal analysis of 493 males and 475 females born in 1964 and interviewed on a yearly basis for 14 years, beginning in 1979, as part of the National Longitudinal Survey of Youth. Body size at age 17, measured as ponderal index, and obesity, measured as BMI, are found to predict higher fertility by age 29 for large or obese females. This effect is not diminished much when controlling for age at first birth. No relationship is found for males. These results mirror results from studies of obesity and social class [Argyle, 1994].

Average physical size was found to vary significantly by race for females, as was the effect of size on fertility. No significant variation in size or effect by race is found for males.

A stronger evolutionary understanding of body size and fertility will be attained once it is possible to analyze directly the contribution of obesity­related alleles to completed family size.

Selective Impairment Of Cheater Detection: Neurological Evidence For Adaptive Specialization

Valerie E. Stone

Center for Neuroscience, UC Davis

Leda Cosmides and John Tooby

Center for Evolutionary Psychology, UCSB

People perform well when reasoning about both social contracts (rules of the form, "If you take the benefit, then you pay the cost") and precaution rules (rules of the form, "If you are in hazardous situation X, take precaution Y") on the Wason Selection Task. Researchers have debated whether reasoning performance in these two domains can be explained as the result of one mental mechanism (a permission schema) or two different mechanisms (a social contract algorithm and a precaution algorithm). We present data from a neurological patient with bilateral orbital frontal and anterior temporal damage who has a selective deficit in social contract reasoning (46.6% correct on a set of social contract problems vs. 74.2% correct on precaution problems). Control subjects performed equally well on both types of problem. Two other orbital frontal patients performed at 78.6% correct on social contracts and 82.9% on precautions. A sample of 37 undergraduates performed at 63% correct on social contracts and 66% on precautions. We believe these results support the hypothesis that reasoning about social contracts and precaution rules are performed by separate mechanisms, using different cognitive resources.

High Child Mortality in Polygynous Dogon Families: Co­Wife Competition or Resource Dilution?

Beverly I. Strassmann and Keith Hunley

Department of Anthropology, University of Michigan

Ann Arbor, MI 48109­1384

Among the Dogon of Mali, West Africa, child mortality is nearly 50% by age five years. To find out whether polygyny contributes to this high mortality rate, we conducted a prospective study of child survivorship over an eight year period from 1986 to 1994 (N = 176). Logistic regression, in which the dependent variable was child survivorhsip (0 = died, 1 = lived), revealed that survivorship increased with age (p < 0.0001, odds ratio 1.5) and wealth (p < 0.05, odds ratio 1.1), was higher for girls than boys (p < 0.06, odds ratio 0.4), and decreased as the number of children in the family increased (p < 0.02, odds ratio 0.8). After controlling for these variables, a child was 7.4 times more likely to survive if the ratio of married females to married males in the family was < 1.5 as opposed to > 1.5 (p < 0.005). Thus, polygyny was the strongest predictor of child mortality in the study population. The Dogon say that co­wives poison each other's children. We compare this indigenous explanation against alternative possibilities such as resource dilution.

Sociosexual Behaviour In The Workplace: Evolutionary Psychology And Public Policy

Michael V. Studd

Faculty of Arts and Science, Nipissing University

100 College Drive, North Bay, Ontario P1B 8L7 CANADA

Sociosexual interactions in the workplace can involve either a congruence or conflict of individual interests, or both. Evolutionary psychology provides a powerful theoretical framework for understanding the ultimate and proximate causes of these complex behavioural and psychological patterns. The better our understanding of the underlying psychological mechanisms, the more successful we should be in developing effective policies for dealing with the positive and negative impacts of such workplace behaviour. Drawing on previous research, and recent suggestions for how such knowledge could be applied, I present some proposals for the development of evolutionarily­informed organizational policy on sociosexual behaviour. Such policy would recognize both the constraining reality and positive aspects of evolved human nature in this area, yet still achieve the goal of minimizing the negative impact of the often conflicting evolved psychological mechanisms ultimately responsible for sociosexual behaviour observed in the evolutionarily novel workplace environment.

Injury Risk And Altruism

Lawrence S. Sugiyama and Richard Chacon, Center for Evolutionary

Psychology, Department of Anthropology, U.C. Santa Barbara

Behavioral data gathered among two indigenous Amazonian groups suggest that variance in foraging returns due to injury can be greater than variance due to changes in foraging "luck" or individual differences in hunting success. Such losses can be substantial (up to two months or more of foraging inactivity). Thus, periods of injury create adaptive bottlenecks exerting strong selective pressure leading to adaptations designed to deal with these constraints. For any individual injury risk is temporally unpredictable. Further, injured individuals are vulnerable to exploitation, least able to enforce pre­existing reciprocal relationships, and in poor position to initiate such relationships. Thus adaptations designed to provide means of insuring aid in times of serious injury have evolved that do not depend on tit­for­tat exchange. Effects of these adaptations can be seen on sharing patterns, group size, the nature of friendship, and incipient role specialization.

Cuckoldry, Divorce, And Evolution: A Study Of New Zealand Supreme Court

Statistics Of Divorce 1922­1987.

Roger Sullivan and John S. Allen

Department of Anthropology, The University of Auckland, Private Bag 92019,

Auckland, NEW ZEALAND

Supreme Court statistics of divorce in New Zealand are examined in three studies to test evolutionary hypotheses of human reproductive behavior. Study 1 (N=119859) analyses divorce statistics over a 60 year period to test a hypothesis that men will apply for, and be granted divorce on grounds of adultery at a higher frequency than women. Significantly more men than women are found to have been granted divorce on grounds of adultery and a gender specific sensitivity to cuckoldry is asserted as the cause. Study 2 (N=8878) analyses divorce statistics over a 24 year period to test a hypothesis that women will apply for, and be granted divorce by court order at a higher frequency than men. Significantly more women than men are found to have been granted divorce by court order and protection from domestic violence is asserted as the cause. Study 3 (N=132685) tests Fisher's (1989) hypothesis that the duration of marriages in the present will reflect adaptive behavioral trends in human evolutionary history. Statistics of duration of marriage over a 25 year period are examined to test a predicted modal marriage duration of approximately 4 years. Results are unsupportive of Fisher's hypothesis, indicating a modal marriage duration of 6 years.

"Sibling Differences and Darwin's Principle of Divergence."Frank J. SullowayMassachusetts Institute of Technology, Program in Science, Technology and SocietyBuilding E51­006Cambridge, MA 02139

Over the last two decades behavioral geneticists have reached a surprising conclusion: Siblings are little more similar in their personalities than people plucked randomly from the general population. For unrelated children raised together, correlations for personality traits are often negative.

These findings are best understood as an instance of Darwin's principle of divergence. When organisms compete for scarce resources (including parental investment), natural selection tends to favor the most divergent forms. Owing to the possession of "open" genetic programs and a capacity for learning, human offspring achieve the kind of niche partitioning in childhood that other species accomplish over millions of years. In seeking to understand human behavior, the application of Darwin's theories requires a developmental approach in which ontogeny brings about the adaptations that were formerly achieved during phylogeny.

Reflections On Parental And Offspring Strategies In The Transition At Adolescence.

Michele K. Surbey

Mount Allison University, Sackville, N.B. Canada, EOA 3C0

In the life history of Homo sapiens, adolescence signifies a transition from the use of childhood strategies to those employed during adulthood. The onset of puberty marks the beginning of the reproductive life and is, not surprisingly, both affected by previous experience and a trigger for behavioural change. Events at adolescence, surrounding the onset of puberty, offer a unique glimpse into human adaptation, from the point of view of the changing strategies of the developing child and it's parents. Surbey (1990) was the first to report relationships between father absence, heightened levels of childhood stress, and early menarche and consider them within the context of human evolutionary history. Subsequently, similar findings have been reported in a number of human populations and have been interpreted from several evolutionary perspectives. This paper will review the current empirical evidence for various alternative explanations of these findings, examining them from the point of view of both parental and childhood strategies. Discussion will include a consideration of how the modern environment may affect the typical life history of human females, the role of phenotypic plasticity and behaviour­genetic effects versus alternative reproductive strategies, and the interwoven nature of strategies employed by parent and child as reflected in the transition at adolescence.

Group Decision Making: A Study of Cognitive Cooperation

John J. Timmel, David S. Wilson and Ralph Miller

Department of Biology, Binghamton University

Binghamton, New York 13902

Humans may have evolved to cooperate, not only at physical tasks such as hunting and warfare, but also at cognitive tasks such as learning, memory and decision making. We studied decision making as a group­level cooperative activity by having individuals and 3­person groups play the game of 20­questions, which is a challenging decision making task. Groups were twice as successful as individuals at playing the game. Advantages of making decisions in groups include memory, motivation, the generation of alternatives, and the evalutation of alternatives. Our results suggest that humans can easily merge their mental activities into a single, coordinated decision making process.

Beyond Kin Selection And Reciprocation: Other Selection Pressures For Adaptations For Altruism

John Tooby and Leda Cosmides

Center for Evolutionary Psychology, CORI, University of California, Santa Barbara 93106

tooby@alishaw.ucsb.edu fax: 805 965­1163 phone: 805 893­8720

The definition of altruism currently accepted in evolutionary biology requires that an organism incur a fitness cost in the course of providing others with a fitness benefit. New insights can be gained, however, by exploring the implications of an adaptationist version of the "problem of altruism" as the existence of complex functional organization designed to deliver benefits to others whether such delivery is costly or not. Such an analysis makes clear that there potentially may be, in a species, many distinct and separable sets of adaptations for altruism designed to deliver benefits to different targets for quite independent reasons. We believe that reciprocal altruism and kin selected altruism are only two pathways out of a larger set, and discuss how some other pathways may be modelled. These models allow one to understand aspects of the design and social dynamics of human friendship (and perhaps mateship) that are otherwise mysterious, such as why overt and explicit reciprocation is taken as a sign of the absence of friendship.

Intersexual Machiavellianism: The evolution of manipulation and deceit in

human mating

William Tooke

A review of research pertaining to deceptive intersexual and intrasexual interactions in humans will be presented. Special attention will be paid to recent research that focuses on sex differences in the "intrapsychic" consequences of deceptive intersexual communication. The relevance of these results for the hypothesis of self­deception by males is considered. Future directions such as research in strategic jealousy induction and deceptive female orgasm are discussed.

Parental Investment among the Vadabalija of Andhra Pradesh, India: A Test of Kin­Selection Theory

Deborah J. Walker and Arindam Mukherjee

Department of Social and Behavioral Sciences

Armstrong State College

Savannah, GA 31419

Kin selection theory predicts that individuals should bias investment in kin according to their degree of relatedness, the benefit to the recipient, and the cost to the actor. To our knowledge, this study is the first to examine differential parental investment by degree of relatedness to offspring in humans. On average, offspring of endogamous marriages are predicted to receive greater parental investment than the offspring of exogamous marriages, due to the greater degree of relatedness between parents and offspring. Genealogies, reproductive histories, and anthropometric data were obtained from several Vadabalija villages along the north­east coast of Andhra Pradesh, India. The Vadabalija are a marine fishing caste. Endogamous marriages (cross­cousin and uncle­niece) have been common among the Vadabalija for many generations; hence, the costs of inbreeding are greatly reduced in this population (Sanghva,1966). Study families, in which at least one sibling practiced endogamy and at least one sibling practiced exogamy, were selected. Reproductive histories were collected from women in the study families, and anthropometric measurements of their children were taken and used as indicators of parental investment. We report here the results from 35 children measured in Uppada, one of the Vadabalija villages. Compared to the Indian National Growth Standards (ICMR, 1984) (controlling for age and sex), the non­inbred males (n=8) were 5.25% shorter and weighed 5.68% less than the mean, whereas the inbred males (n=10) were 3% shorter and 5.8% heavier than the mean. Non­inbred females (n=8) were 4.68% shorter and weighed 11.1% less than the mean, whereas the inbred females (n=9) were 0.2% taller and 3.29% heavier than the mean. In sum, inbred children were taller and heavier on average compared to non­inbred children. We are currently examining other indicators of parental investment in the Vadabalija villages (sex ratios, risk of mortality, birth intervals, and duration to first menses after childbirth).

Risk Variance­Sensitive Choice Model: Empirical Examinations and Computer Simulation

X.T. Wang

Psychology Department

University of South Dakota

Vermillion, SD 57069, USA

The current model tries to capture the stochastic nature of decision environments and variability in choice options; it takes into consideration both the means and variances of expected utility values. The model assumes that people make their choices by comparing the expected values of choice options with a task­specific criterion (i.e., the minimum requirement for gains or the maximum tolerance for losses). The result of such comparisons determines the risk preference. Decision makers tend to be risk­averse if the mean expected value of choice outcomes is above the criterion point, otherwise being risk­seeking for higher variances increase the likelihood of a mean reaching the criterion point. Both empirical examinations and a computer simulation were conducted to test the model. In different decision contexts, the criterion point may vary adaptively as a function of various social and ecological factors, such as size of social group, kinship, survival ratios described in a choice problem, task domains (e.g., life­death vs. monetary problems), age of decision makers and decision recipients, etc. By incorporating these factors, the current mode accounts for observed choice biases that violate rational principles of traditional utility theories, and makes specific and testable predictions about risk preferences in human choices.

Languages of Description, Languages of Command

Dennis P. Waters

1 Palmer Square, Suite 315

Princeton, NJ 08542

While the centrality of language to the evolution of human social behavior is readily conceded, convincing explanations for the evolutionary function of language have been hard to come by. Trying to explain language in terms of communication or cognition begs the question by merely exchanging one difficult concept for another. Since evolution is fundamentally about behavior, any evolutionary explanation of linguistic function must specify a behavioral connection. In this context language can do two especially useful things: it can describe and it can command. Its power of description connects language to the human perceptual system and its power of command connects it to the human motor system. Since arguably it is the functional coupling of perception and motor action that yields evolutionarily interesting behavior, the dual ability of language both to describe and to command would appear to be a fundamental property in the context of evolution.

Kids Having Kids: An Evolutionary Perspective

David Waynforth, Hillard Kaplan & Jane Lancaster

Department of Anthropology

University of New Mexico

Belsky, Steinberg and Draper have hypothesized that factors such as high levels of family stress and father absence during childhood alter offspring psychosocial development so as to promote the adoption of particular reproductive strategies. These strategies include 'problem' adolescent behaviors and early reproduction in unstable unions. Alternatively, Kaplan's theory of human capital explains early reproduction as a function of parental investment and labor­market skills: children who receive little parental investment, or who lack innate ability to compete successfully in a competitive labor market should be less likely to invest time in accrual of skills or capital prior to reproduction, as their fitness gain will be lower than would be gained via early reproduction. This paper presents an evaluation of both of these theories, along with the hypothesis that the timing of first reproduction is a directly inherited trait, using data collected on the reproductive histories of 650 men in Albuquerque, New Mexico.

Marriage: Learning by Looking

Carol C. Weisfeld*, Glenn Weisfeldt**, and Norma J. Schell***

*University of Detroit Mercy, **Wayne State University

*Dept. of Psychology, 8200 W. Outer Dr., Detroit, MI 48219 USA

Before the 1970's, marriage research was essentially questionnaire research concerning wives' perceptions of marital dynamics. Now there is a wealth of data on both spouses' perceptions of the marriage relationship. But with few exceptions (e.g., Gottman, Noller) researchers have not examined how couples actually behave. Observational research has identified a few promising correlates and predictors of marital quality Our research has focussed on couple interactions while making a joint decision in the home. The goal has been to explore the relationships among couples' perceptions of their marital dynamics, objective outcomes of a decision­making process, verbal process used in communicating, and nonverbal expressions (visual dominance, touching, smiling). Happier couples were characterized by perceived husband ascendancy in decision­making, and by his visual dominance during decision­dominance, however, was not necessarily correlated with his prevailing in the decision. Younger couples took more time to negotiate, while older couples seemed to rely on "scripts" which provided a quick, apparently pre­determined decision. Videotaped footage of three different couples making the same type of decision will be shown. Results will be discussed in terms of the importance of nonverbal signalling for status recognition purposes.

The Evolution of Norm Compliance: Studies of Fitness­Relevant Attributions Consequent on Social Norm Violations

Brant Wenegrat, Lisa Abrams, and Eleanor Castillo

Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine

Self­presentation and social­identity theorists have shown that people attempt to comply with prototypical norms of groups with which they identify. While cultures differ in the importance they attach to norm compliance, some compliance with prototypical norms is evident in all societies, suggesting that it depends on universal cognitive and emotional dispositions. As part of a research program to determine the fitness advantages conferred by compliance with norms, we have performed a series of experiments in which subjects view models violating or respecting trivial social norms and then rate them on dimensions, such as romantic attractiveness, which would be relevant to their fitness in real social settings. Multivariate analyses of variance of these ratings show powerful invidious effects of momentary minor norm violations of diverse types. Based on our experimental findings, we propose that deviations from prototypical behaviors are "information rich," in contrast to prototypical behavior itself, which is "information poor," and that norm compliance is a method of controlling others' fitness­relevant attributions.

The Importance of Attributes in Mate Preference Studies: A Methodological Investigation

Adam Wetsman

Department of Anthropology

University of California, Los Angeles

Mate preference studies have generally confirmed predictions derived from evolutionary theory. Specifically, males have been found to favor traits relating to female attractiveness, while females have self­reported a greater interest in attributes relating to male resource acquisition. One aspect of such studies that has been largely overlooked is that when individuals are presented with a group of several attributes to rate, those traits in which sex differences have been observed are usually rated relatively low. This study investigates the possibility that the methodology employed in earlier studies constrains the choices made by individuals, artificially lowering the rankings of some attributes. A mate preference survey was administered using three separate scaling systems in order to test this possibility. Some changes in the ranking of the attributes were observed, especially those in which sex differences have been observed in the past. A computer simulation revealed that some of these changes could not have occurred by chance, indicating that the methodology affected the rankings of a few attributes. These results suggest that we should exercise caution when interpreting results of previous mate preference studies.

Can Sex Displace Violence? Modeling the transition from Pan

Troglodytes to Pan Paniscus

Paul Whitmore

Psychology Department, Stanford University

Jordan Hall, Stanford, CA 94305­2130 wit@psych.stanford.edu

Researchers now appreciate that the Bonobo (p. paniscus) is a distinct species from the common (p. troglodytes) chimpanzee. One intriguing difference between the two species concerns the mechanisms of alliance­formation. Among p. troglodytes, status hierarchy is maintained solely via male­male alliances. Males spend the majority of their time in the presence of other males. Females associate only through connections with males (Goodall, 1986). Both in captivity (de Waal) and in the field, Bonobos have been observed to maintain status hierarchies through females. How were Bonobos capable of socially organizing to distribute power in such a different manner? Following a speculation of Wrangham's (1993), I develop a simulation of Prisoner's Dilemma interactions to explain this transition. Common chimpanzee society begins in a state where aggressive displays isolate females. By increasing the opportunity to feed in view of conspecifics (hypothesized to be responsible for the speciation of Bonobos) troop members can accumulate information about interactions between individuals. This social information can be exploited to form alliances that defend against future defections, and improve the accessibility of social ties that are not vulnerable to aggressive threats.

Family Structure and Child Outcomes: Data from the National Longitudinal

Study of Youth

Richard P. Wiebe and Hobart H. Cleveland III

Department of Psychology

Department of Family Studies

University of Arizona, Tucson, Arizona

The National Longitudinal Study of Youth (NLSY), conducted by the Department of Labor, began in 1979 with a representative sample over 11,000 respondents born between 1957 and 1964. Since then, many have had children, and the children of the NLSY subjects have been followed biennially since 1980. Our poster, incorporating data from 1988, 1990, and 1992, relates children's scores on behavioral and intellectual measures to the structures of their families. Children living apart from their biological fathers, whether with their mothers alone or with a stepfather or other male as well, evinced more behavioral problems, as reported by their mothers, and performed more poorly on intellectual measures than did children living with two biological parents. Among two­adult families, biological relatedness between the father and child predicted significantly more variance in child outcome than did the intactness of the marriage. In addition, we provide descriptive statistics reiterating the familiar relationship between race and family structure, with more African­American than Hispanic and other children living with single parents. We discuss possible limitations of the of the data, including the bias of the sample towards young parents, whose children generally fare worse than those of more mature persons.

Human Computer Interaction and Darwinian Medicine

Amanda M. Williams, Ph.D.

Cognitive Psychologist

Solana Beach, CA

Recently, the quickening pace of information technology overtook this author. For two decades the author, an applied cognitive psychologist, has studied human behavior in real world settings. These findings have been coupled with basic research for the design of information systems that optimize human computer interaction. After a brief sabbatical, this author found that the tools she used were out­of date. New tools had such increased capability that it was imperative to use them. The retraining was a loss of several weeks of productivity.

The costs of constantly evolving technology are obvious on such an individual basis, but what are the implications for an information based society as a whole? When do the benefits of using the upgrades outweigh the costs? This paper speculates on how Darwinian Medicine could be used as a model to examine such questions and how conclusions reached based this type of analysis would give designers improved solutions in future development.

The Nuer Conquest: A Case Study Of Cultural Group Selection In Action?

David Sloan Wilson

Department of Biological Sciences, Binghamton University,

Binghamton, New York 13902­6000

dwilson@bingsuns.cc.binghamton.edu

Evolutionary biologists are often forced to study the products of natural selection­­adaptations­­which evolved in the distant and unknowable past. However, the ultimate demonstration of natural selection is to actually monitor the process of more adaptive traits replacing less adaptive traits. Examples from biology include industrial melanism, guppy coloration and the beak dimensions of Darwin's finches. In Anthropology, one of the best documented examples of cultural replacement is the Nuer, who greatly expanded their territory at the expense of neighboring tribes during the 19th century. The causes of the Nuer conquest are well understood, based on five decades of research. When this research is interpreted from an evolutionary perspective, it seems to provide a detailed case study of cultural group selection in action.

ADAPTATION AND INDIVIDUAL DIFFERENCES

David Sloan Wilson

Binghamton University, Binghamton, New York 13902­6000

dwilson@bingsuns.cc.binghamton.edu

Natural selection often promotes a mix of behavioral phenotypes in a single population. Multiple adaptive phenotypes have been best documented for male mating behavior but they also exist for other behaviors such as foraging and the propensity to take risks. The adaptationist perspective leads to a different view of individual differences than traditional psychological perspectives. In particular, personality traits such as shyness and boldness are often assumed to be domain general whereas they should be domain specific from the adaptive standpoint. Rather than thinking in terms of a relatively few axes of behavioral variation, it is important to think about the behavioral strategies that are adaptive in specified situations. It then becomes obvious that adaptive individual differences will vary across situations in ways that are difficult to represent by a small number of linear axes. These general points are illustrated with studies of shyness and boldness in pumpkinseed sunfish (Lepomis gibbosus).

Analogy, Human Evolution and the Common Law

Paul C. Wohlmuth

Professor of Law, University of San Diego and

Director, Institute for Law and Systems Research

5998 Alcala Park, San Diego, CA 92110­2492

In illuminating the nature of analogy, recent work in neurobiology and cognitive psychology on memory and recognition is shedding new light on law's role in human evolution. The common law, usually associated with legal systems originating with the medieval English courts, has begun to emerge as a more global institutional process pushed out of and supporting the spatiotemporal complexity of human memory. A revealing conundrum is generated that the stability of successive sociopolitical arrangements in human history is undermined in each instance by overreliance on some form of explicit memory, most recently "text" in modern societies. Analogy, the common law's dominant cognitive strategy, appears to mobilize and express the continuously evolving advantage of the human mind to precipitate and process memory traces in multiple time scales and funnel them through the pressure of problem­solving in the present. The contemporary result is a dynamics of authority, precariously balanced between explicit and implicit memory, which distributes political and economic power over a range of sociopolitical entities, from individual humans to nation states and multinational corporations, whose viable scaling and interrelationship are problems that our species is currently under enormous pressure to solve.

The Abandoned Mother Theory of Bulimia Nervosa

Sabura L. Woods and Kent G. Bailey

Virginia Commonwealth University

810 West Franklin Street

Richmond, Virginia 23220

The Abandoned Mother Theory of bulimia nervosa proposes that bulimic symptoms are behaviors based on the adaptive mechanisms of a reproductive strategy that evolved in response to environments where women were likely to be abandoned. This reproductive strategy would be employed by a woman who had conceived, or who perceived conception as imminent, and was responding to an environment in which resources were viewed as unpredictable or unreliable. Such circumstances of abandonment could include being kidnapped, famine, illness or death of a mate. Therefore, a reproductive strategy that maximized a mother's ability to gather resources on her own would insure the survival of her and her child. In vulnerable women, this same strategy could be activated by stressors in current cultural contexts due to tension arising from dissonance between evolved adaptations and more current environments. Characteristics of bulimics and their related behaviors, such as bingeing, stealing, and promiscuity, seem consistent with context­inappropriate activation of an "abandoned mother" suite of characteristics in nonpregnant women.

The Meek Shall Inherit The Earth

John V. Wylie, M.D.

3801 Northampton Street, NW, #3

Washington, DC 20015