Human Behavior and Evolution Society

 

 

Second Annual Meeting August 16-19, 1990

University of California, Los Angeles

 

 

 

 

Abstracts

 

 

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

 

The Convolutedness of Morality

 

Richard D. Alexander

 

The evolutionary approach to human behavior has two terrible problems. One is, of course, that evolution is accepted by only a miniscule proportion of the world’s population. The other is that, even within that miniscule proportion, academicians and the intelligentsia tend to wall us off like a malignant tumor. This happens partly because a minority of thoughtful people are educated in biology, and partly because of the convoluted nature of human efforts to self-understand, owing to the biological history that no one wants to hear about.

We lose, in analyzing these problems, if we discuss only the brighter side of human nature or claim that the topic is cooperation not competition. Moral philosophers and academicians for the most part live in pleasant worlds, with little opaque clouds that tend to admit only the delightful aspects of human intentionality floating above their heads as they move along the sidewalks of urbania between their offices and their homes. But there is misery in the world, and it is not all there because of pathologies easy to understand or proximate causes easy to remedy; nor is it all owing to those “other” kinds of people. Moreov~ç, civilization and technology have created a circumstance in which virtually all human striving, designed as it is to better the current quality of life, threatens increasingly the future of humans, or even of life itself.

Analysts of morality must retreat from their subject far enough to examine the reasons for its convolutedness. We must know how kindness, beneficence, and good fellowship can be selfish, and we must also understand why the idea is repugnant and what to do about that. Most important, to solve the problems we human evolutionists have glimpsed so far, we must enlist a far greater proportion of the world’s thinkers, If, as knowledgeable people increasingly suggest, massive altruism by our generations will be required to ensure the survival of later generations, then unless we don’t care we have to know to reverse the relevant aspects of the striving we have evolved to accomplish. We have to know how to use the fact that no part of biological theory has ever legitimately implied that humans cannot employ their evolution-given traits to set and accomplish goals that are entirely incidental -- even contrary

-- to their history of natural selection.

 

there is no alleviation for the sufferings of mankind except veracity of thought and of action, and the resolute facing of the world as it is when the garment of make-believe by which pious hands have hidden its uglier features is stripped off.”

 

-- Thomas Henry Huxley, 1909.

Autobiography and Selected Essays,.

NY:           Houghton-Mifflin, p. 13

Juvenile Nutritional Condition and Kin Composition among the Piro of Lowland Tropical Peru

 

Michael Alvard & Hillard Kaplan, Department of Anthropology, University of ~ew Mexico, Albuquerque, N.M. 87131

 

The number and nature of kin present in a population varies between its members. In traditional human populations it is frequently from kin that individuals acquire resources and it is often between kin that competition for resources is greatest. The number and productivity of kin is particularly important for juveniles who cannot acquire for themselves the nutrients they require for growth. It is hypothesized that juveniles with more dependent kin and fewer productive kin suffer greater competition for fewer resources, while juveniles with fewer dependent kin and more productive kin suffer less.

The data presented to test this hypothesis were collected during fieldwork with Piro Indians of the lowland tropical rainforests of southeastern Peru in 1988-1989. The Piro are subsistence horticulturalists who acquire most of their calories from gardens of manioc and plantains, and most of their protein and fat from fishing and hunting. Preadolescents acquire only a small amount of the calories they require.

Evidence for competition between dependent kin is measured using anthropometric data. Weight for height (wt/ht), controlling for age, was calculated for each child between the age of 3 and 12. Kin composition is quantified by calculating the coefficient of relatedness between each juvenile and each other member of the population using a computer program written by Jeff Long of the University of New Mexico. Using resource acquisition data, each kinsperson of each juvenile was assigned a coefficient of productivity indicating surplus or deficit caloric production.

Preliminary analyses indicate a significant negative relations~ip between weight for height and the number of dependent kin a juvenile has (r — 0.26, p

— 0.003). When juveniles were classed by2sex, it was found that the relationsh~p exists for male juveniles (r — 0.66, p — 0.0001), but not for females (r — 0.058, p — 0.338). The number of productive kin has no effect.

 

 

 

 

 

 

 

Patterns of intra-cultural variation in food avoidances in the Ituri Forest, Zaire

 

Robert Aunger, Department of Anthropology, UCLA

 

A 95% complete, geographically contiguous sample of 350 individuals over age ten situated in the northeast corner of the Ituri Forest, Zaire was interviewed in 1989-90 concerning their food avoidances. Summary statistics on variation in avoidances by age, sex, and tribal group in a subsample of approximately 90 individuals will be presented. 300 household months of animal consumption data will be used to examine the hypothesis that rare animal foods tend to be avoided, and ethnofaunal classification data will be used to investigate whether or not anomalous animals figure si~nificantly in

this population ‘S food avoidances,

Selfishness and Altruism:      Effects of RelatednesS Ofl ManipulatiVC and Helping Attitudes

Nigel Barber

Department of Psychology

Bemidji State University

 

Machiavellianisu (the tendency to be socially manipulative) is considered to be a personality trait. This means that individuals who are highly manipulative in one situation should behave similarly in others. Evolutionary theory predicts, however, that social strategies should vary between related and nonrelated targets. MachiavelliafliSm is similar to the biological concept of selfishness and would thus be predicted to be lower in relation to kin. Socially manipulative attitudes of college students were assessed in relation to either “people” or “family members” using modified MachiavelliafliSlfl questionnaireS. Subjects were significantly less manipulative in their attitudes toward kin. The finding suggests that social psychologists would benefit by manipulating relatedness in the study of personality, attitudes, and social behavior. In particular, kinship may shed some light on prosocial (helping/altruistic) behavior. Social manipulativeness was higher in males and was inversely correlated with size of a subject’s home town. The number of stepchildren in a home was not related to Machiavellianism. These findings are discussed in terms of evolutionary psychology.

 

 

 

The Evolution and Antitheses of Games and Scripts

C].audette H. Beahrs, M.S.S.W.

Clinical S.W. and Transactional Analyst

3318 N.E. Hancock Street

Portland, Oregon 97212

 

This theoretical and clinical presentation focuses on the relationship between recent trends in evolutionary biology, psychoanalytic state theories and the theory and practice of transactional analysis developed by Eric Berne. Trivers and Slavin postulated that the inevitable competition between parent and offspring leads to deception as a viable and necessary defense. Getting offspring to behave in the best interests of the parent rather than the child while carrying out the prescribed role of caretaker of the young, requires self—deception and dual messages on the part of the parent. This leads to non-trust and a self-protective deceiving of the parent by the child who also responds in a dual way —- overtly appearing to comply to the parental demand while privately making decisions out of primitive self—interest. In the theory of games and scripts Berne and colleagues elegantly developed a concise system for describing the outgrowth and perpetuation of this extraordinary conflict between mutual need and competition, subtly and sometimes blatantly carried on between parent and offspring throughout life. The conflict eventually encompasses and involves all human relationships to some degree and Is perpetuated f’rom generation to generation. Strategies for interdiction of these patterns Utilizing an

evolutionary perspective will be presented along with the historical and theoretical overview.

The Evolution of Criminal Justice

John 0. Beahrs, M.D. (ll6A-OPC)

Oregon Health Sciences University, and

Portland V.A. Medical Center

P.O. Box 1036, Portland, OR 97207

 

Criminal justice is riddled with paradoxes, unresolved in legal theory. Foremost, culpability requires volition, but causal research suggests that voluntary and involuntary action are inseparable. Further, elements of three competing legal models of justice contribute, but elude integration:

(1)    utilitarian (societal defense), (2) retributive (just deserts) and (3) rehabilitative (medical). Evolutionary biology may clear the confusion by clarifying the role of collective self—deception in the evolution of cooperative social systems. Society and its members co—equilibrate along the truth-deception continuum, leading to a vivid but illusory separation of voluntary from involuntary, and a societal tension between what actually occurs (realism) and society’s organizing ideals (idealism). The three models of justice are understood in this context: (1) utilitarian, most realistic, is essential to social survival but vulnerable to abuse;

(2)    rehabilitative, most idealistic, supports a partly deceptive image of social beneficence that helps bind society’s members; (3) retributive, most dependent on volition, reinforces individual autonomy and modulates the other models. All are legitimized by evolutionary traditions that antedate homo sapiens, and none is entirely sufficient. Elements of all three models necessarily co—exist within any existing society, their relative strength varying with its collective values, prosperity, and perceived safety.

 

 

 

 

 

 

 

Who’s Pro-Choice and Why?

Laura Betzig

EHB/lOO Rackham/Tjniversity of Michigan/Ann Arbor MI 48109

 

A lot of attention has been paid to abortion as a moral problem. Relatively little has been said about abortion as a reproductive problem. Adults in Ann Arbor area households will be asked by phone about abortion and family cczrçosition. Their answers will be used to test ten predictions: 1) women will, overall, be more pro—choice than men; 2) pre—menopausal women will be more pro—choice than post—menopausal women; 3) single women will be more pro— ch~e than married women; 4) married men will be more pro—choice than single men; 5) people with single, reproductive, sisters will be more pro-choice than people without; 6) parents with single, reproductive, daughters will be more pro—choice than parents without; 7) pro-choice attitudes will increase in strength with each of these demographic factors; 8) pro—choice voting will increase with each of these demographic factors; 9) contributions of money or time to the pro—choice cause will increase with each of these demographic factors; and 10) over time, social attitudes and practices with respect to abortion may increase with the number of young, unmarried, women in the population.

EGALITARIAN SOCIETY AS AN EFFECT OF AMBIVALENT HUMAN NATURE

 

Chris Boehr’, Professor of Anthropology

Department of Anthropology, Sociology and Philosophy

Northern Kentucky University

Highland Heights, KY 4l~76

 

Egalitarian society is characterized by political anthropologists as having weakly developed leadership, lack of hierarchy among adult ,uiales, and an egalitarian ideology, all caised by a.ztomatically-acting “leveling mechanisms’ (e.g., nomadis,’i prevents economic stratification). However, its existence remains anomalous since all African apes and all I~uman societies above the tribal level exhibit decisive control of followers by their leaders. To explain this anomaly, I examine behavioral propensities in htn’ian nature which suggest that while development of hierarchy is very likely, many higher primates also exhibit subtle tendencies for disgruntled subordinates to control leaders. An extensive cross-cultural survey suggests for humans living in bands or small tribes some unobvious but effective proximate mechanisms by which followers deliberately manipulate leaders into a situation of powerlessness. The conclusion: tribal humans are genetically prepared to be ambivalent about leadership, in that useful leaders unfortunately tend to increase personal power. They express such ambivalence by carefully keeping their leaders all but powerless. However, in chiefdoms and kingdoms the same ambivalence remains unexpressed beca~se coercive leaders can suppress attempts at control from below. Implications are drawn for modern states and current events in Eastern Europe.

 

 

 

 

 

Competing for Mates

 

David M. Buss and David Sehmitt

 

Department or Psychology

University of Michigan

Ann Arbor, MichIgan 48109-1346

 

Abstract

 

Previous studies have shown that men and women differ in reproductively-relevant ways in their preferences for long-term mates (D.M, Buss, ~haYiQr~1 and Biain Science. 1989, 12, 1-49) as well as short-term mates (Buss & Schmitt, under review). Mate preferences of one sex should powerfully influence the tactics of intrasexual competition used by the opposite sex. Three empirical studies were conducted to test evolution.hascd hypotheses about the tactics that mcn and women usc in competing for short-term and long-term mates. Men were round to display many of the same tactics of mate competition in both contexts ~e.g., ts), but deceived women about their long-term intentions as a tactic to obtain short-term copulations. Signals of immediate sexual access were effective com~,etition tactics for womcn in attracting short-term mates, but si~ns of sexual restraint Were tTIOre effective in attracting fong-tcrm mates. ~ focuses on the implications of these results for the sextia[ strategies of men and women.

Competition and Dornina.nce in Women and Men

Elizabeth Cashda.n

Department of Anthropology, University of Utah

 

 

How competitive axe women and men, and what do they compete for? In most species, females compete for material resources while males compete for access to mates. Because of high paternal investment, it is hypothesized that the opposite pattern generally prevails among humans, with females competing for investing males and males competing for the resources needed to invest. The degree to which this is so should depend on the extent of pa.­ternal investment. Work currently in progress is being conducted to evalu­ate hypotheses concerning (a) whether sex and expectations about paternal investment a±fect the object of competition (mates vs. resources) in women and men and (b) whether dominance behavior in females is suppressed in mixed-sex settings, and, if so, whether such suppression is greater among women who anticipate high levels of paternal investment. These hypotheses are being evaluated with data from same-sex residential groups of adults. The data consist of (a) behavioral data from small-group interactions, (b) peer rankings, (c) competition diaries, and (d) background data concerning expectations about paternal investment.

 

 

 

 

 

 

 

 

Art:    The Replicable Unit

 

Kathryn Coe, College of Nursing, Arizona State University. Tempe, AZ 85287

 

The definition of art, little changed since Plato, has been nonskeptically

accepted by a large number of scholars, included among whom would be a number of evolutionary biologists. This inheritance, unfortunately, may not be a

fruitful one. In this paper, definitions of art (explicit and implicit)

utilized by scholars attempting to identify the origin of art will be briefly summarized and evaluated. An alternative definition, that focuses on a

replicable unit, will be proposed. An attempt will then be made to identify the origin or art among our early ancestors and to account for its initial

transmission.

A Survey of the Introduction of Evolutionary Theory and Sociobiological Concepts in Human Economic Behavior.

 

 

 

Roland Corluy

 

Karel Van Schoor

 

Johnny Zeven

 

Free University of Brussels (V.U.B.),

 

Center for Biomathematics,

 

Pleinlaan 2, 1050 Brussels

 

Belgium

 

 

The last decade has shown a considerable input of sociobiological concepts in economic literature. Due to the failure in real—life situations of classic economic models, which do not take into account in their defini­tion of “homo economicus” the biological roots of human nature, several economists introduced the theory of “natural economy”. Concepts such as “utility” and “economic fitness” will be discussed from an evolutionary viewpoint. An attempt will be made to include sociobiological concepts into the newer non—linear economic models. It will be shown that these models, although being closer to reality, may be of little relevance for practical economic prediction purposes.

 

 

 

R~ID~, mATE~IESS, A~W ~H~ES N~flG ~ I4W~JO O~ KUffA

Lee Crcdc

Dept. of Anth., Texas A5M University., College Staticm, TX 77843-4352

 

The Mukogodo, a ul 1 group of Mu-speaking Kenyan pastoral ists, live in scattered settlutmfls of ten to fifty people. Their preferred form of residence is virilocal, with the core of a typical settlanent ccr~sisting of a group of related uules. HcMever, it~ny other residential patterns also exist, incltuiing sett1eui~ts with cores of related fenules, siblings of both sexes, and t.mrelated friends. Coresidence provides the Mukogodo with Tinny opportunities for cooperatia~i in suheist&ice and social activities incl~ing food sharing, labor sharing, cam~ defense of herds against predators and thieves, and spcz~sorship of cera~iies and cel ebratia~is. Although n~st sett1~its last several years, there are frequent changes in their caipositj.cri as individuals and fanuliez move fran ~e ~ett1&i~it tQ another. This paper exanines the re1ati2~ship between residence and genetic relatedness axm:ng the Mukogodo, paying special attenti~ to instances in which the virilocal residential norm is violated and to the relatiooship between relatedness and changes in settlur~nt carpositi~.

“Deconstructing” Symbolic Interpretations of Cruel Stepparent Stories

 

Martin Daly & Margo Wilson

 

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

 

 

The enslavement, sexual exploitation, abuse and destructive neglect of children by stepparents constitute recurring themes in myth and folk tales from diverse societies the world ‘round. Cinderella and Snow White are familiar European examples. Anthropological, psychoanalytic and feminist interpretations of these stories often differ, but they concur in treating a crucial fact -- that the villains of these stories are stepparents

--   as irrelevant to their “real” meanings, which are usually alleged to concern (suppressed) antagonisms characteristic of genetic parent-offspring relationships. Ironically, the overt content of these tales has much more to do with behavioral and psychological reality than does their supposed symbolic content: As selectional thinking would lead us to expect, step-relationships are vastly more conflictual and dangerous than genetic parent-offspring relationships.

 

Besides overlooking the centrality of the theme of the unreliability of substitute parents’ interest in their wards’ welfare, proponents of symbolic interpretations of these tales have ignored the question of why they appeal to the social purposes of the adults who tell them as well as to the children who listen. Why should parents, who best serve their own interests by fostering childish trust in parental benevolence, choose to entertain their children with lurid symbolic accounts of parental malevolence? But if we take the surface content of these tales seriously instead of assuming that they are “really” about something else, this problem evaporates: It is easy to understand the appeal of cautionary tales about the evil nature of stepparents, both for the audience (children) and for the tellers (parents, grandparents and other adult relatives). And if mothers are the principal story-tellers, these considerations also explain why cruel stepmother stories are apparently more common than cruel stepfather stories though stepfathers constitute the greater hazard.

 

If there is an interesting “depth psychological” puzzle about all this, it is why scholars continue to deny and obfuscate the fact that step-relationships and genetic relationships are qualitatively different.

Title:         Human Suicidal Ideation and the Residual Capacity to Promote Inclusive Fitness

Author:       Denys deCatanzaro, Associate Professor, Dept. of Psychology, McMaster University, Hamilton, Ontario, L8S 4K1, CANADA

 

Abstract: Mathematical modeling, based on an elaboration and integration of inclusive fitness theory and the theory of senescence, suggests that natural selection in highly social species may engender self-preservative tendencies that are only conditional. It is predicted that where there is a confluence of poor reproductive prospects and burdensomeness toward kin, expression of outright self-destructive behavior may be favored. On the basis of extensive literature reviews, it has been argued that human emotional and behavioral dynamics show correspondence to these pressures. In diverse cultures, suicidal behavior is most frequently observed in circumstances of such confluence. This lecture will report new data from surveys of a large sample of the general public and of high—suicide—risk populations, including elderly, psychiatric, criminal psychiatric, and homosexual individuals. The survey form probed family contacts, reproductive status, and depressive and suicidal ideation. Multiple regression within each sample showed that between 50 and 80 percent of the variance of suicidal ideation is predictable on the basis of reproductive and family-social variables. Within all samples, survey items related to burdensomeneSs toward family were most highly correlated with suicidal ideation.

 

 

 

 

Music as a Human Behavior: An Hypothesis of Evolutionary Origin and Function.

 

Ellen Dissanayake

New School for Social Research

 

Mailing Address: 329 W. 20th Street

New York, N.Y. 10011

 

Music is not an obviously vital need, yet it is universally present and highly valued in human societies. This universality and cultural prominence suggest that music has contributed something essential, not simply ornamental, to human existence, and was thus selected for during our evolution. But where did it originate and what was its selective value? Recent studies of playful, pleasurable mother—infant interaction have shown innate receptiveness to intonational contour and change, to temporal manipulation, and to other prosodic devices which —— elicited by infants and manipulated by mothers —— contribute to bonding and acculturation. In both mother—infant interaction and adult musical experience, the form and result have a provocative resemblance. Each structures, varies, delays, and ultimately satis­fies expectation, thereby creating and manipulating emotion and establishing physiological and emotional synchrony in participants. In other animals, elements of parental behavior have been the apparent origin for many ritualized expressive sounds or actions (releasers) that promote social contact, appeasement, and interaction in adults. One might analogously view genetical1y~endowed pro5vdic eL~iflefl~5 ~f mother....fnfant engagement as the behavioral reservofr for affectir.ig sounds and temporal structures Culturally evolved in ritual cere­monies (which as in other animals promote sociality, conflict resolution and unification in group members) these prosodic/musical elements could ultimately become emancipated as ~‘music,” giving pleasure and satisfaction in their own right, as well as in ceremonial contexts

This paper could not be accommodated in the main program. Those who are interested in discussing the ideas presented in this abstract may contact the author for informal discussion during the course of the meetings.

 

 

 

 

 

 

 

 

 

 

Establishing Bio—Behavioral Grounding in University or High School

Liberal Arts Curricula

 

Ellen Dissanayake

New School for Social Research

 

Mailing Address: 329 W. 20th Street

New York, N.Y. 10011

 

 

Without proposing a specific paper now, I wonder whether it would be possible to begin planning (perhaps for the 1991 Meeting) a symposium or committee to investigate ways in which a basic course in Human Ethology (grounded in fundamental concepts of general evolutionary theory and ethology) might be introduced into curricula in high schools or universities. A selected school whose administrators were receptive to a biobehavioral perspective could perhaps be chosen for a pilot program where such a course could be developed for students whose main interest is in the humanities and social sciences. Ideally, their teachers would also be encouraged to attend workshops in which the perspective is introduced. A model for this might be the social studies program, Man: A Course of Study, developed irt the 1960s for sixth graders by a group at Harvard under the auspices of the National Science Foundation. This was ultimately with­drawn after outraged protests from creationists etc., resulting in Congressional hearings and a general national brouhaha. Can we try again? It seems imperative, to this HBES member at least, that progress in addressing crucial social and political problems in the world today is not possible without having all people who call themselves “educated” being introduced to the concepts of human evolution and human ethology, and aware of their implications. Offering these only to already—interested biology students does not seem sufficient. If there are other HBES members who are convinced of the importance of “spreading the word,” particularly among humanists and social scientists, I would like to hear from them.

Sex Differences in Sexual Fantasy: An Evolutionary Psychological Approach

 

Bruce 3. Ellis, Department of Psychology, University of Michigan, 580 Union

Drive, Ann Arbor, MI, 48109-1346

Donald Symons, Department of Anthropology, University of California, Santa

Barbara, CA, 93106

 

 

 

 

 

The nature and frequency of men s and women’s sexual fantasies were investigated by surveying 307 students (162 females, 12~ males) at a California state university or junior college via a paper—and—Pencil questionnaire. The questionnaire was inspired by modern evolutionary theory and was designed to investigate se~: differences in sexual fantasies. Substantial sex differences were found in the salience of visual images, touching, context, personalid.ation! emotion, partner variety, partner response, fantasi:er response, and inward versus outward focus. These data., the scientific literature on sexual fantasy, the historically—stable contrasts between male—oriented pornography and female—oriented romance novels, the ethnographic record of human sexuality, and the ineluctable implications of an evolutionary perspective on our species, taken together, imply the existence of profound sex differences in sexual psychol ogi es.

Incest avoidance and familial bonding

 

Mark Erickson M.D. New York State Psychiatric Institute. 722 West

168th St., New York, NY 10032

 

It is hypothesized that social bonding in early life canalizes attachment behavior in childhood and, later, incest avoidance and preferential altruism (kin selection). This process—here called familial bonding—is further hy­pothesized to represent a form of social attraction that is evolutionarily and ontogeneticallY distinct from (and opposed to) sexual attraction.

 

 

 

 

 

 

 

 

THE “~JaruRNAL SCH~4A” AND i~ EVOLUTICIf OF HtI.iAZf SCHIDJPHR~IA

Jay R. Feiern~n

DepartDent of Psychiatry, University of New Mexico and Presbyterian

Healthcare Services, AlbxjuerqUe, New Mexico, USA. [~ i’~rk &rhe ,tile

on sabbatical at Forschungsstelle fur Hun~nethologie in der Max-Planck­Gesellschaft, Federal Re~iib1ic of Gerneny.]

~       author previously proposed the testable hypothesis that h~ schizoçtrenia is the diurnal-n.tche-depeFx~flt expression of a z~cturnal­n.iche-deper~3ent pattern of r~uropdxysiological organization, the “r~cturnal schem,” which ordinarily predisposes Individuals possessing it to be active in a r~cturnal niche (Medical ~ 9:455— 479,1982). In this conceptualization clinical scbi.zoitren.ia ~ald result fran a r~cturna21—schei~a-poesessing Individual being “r~rmti~~ely coerced” to be day—active and social. The eirpfrical data su~çorting and conflicting with the hypothesis to date are reviei.aed. As a r~ test of the hypothesis, the author constructed a schemtic neural net~rk n~del, based on reuro~iysiolog1cal data, ~tich sha~.s l~q the circedi.an clocks of diurnal and m~cturnal manm~ls are affected differently by their kr~’ri “zeitgebers” (light, tei~çerature, eating, and social interaction) . * In the n~del diurnal mini ‘s cfrcaiian clocks are w~ut vu]Derinblu to zeitgeber—Irduced changes (itase shifts) during the dark (rather than rest] itase, whereas r~ct~ni~al nmiinl ‘s circaitan clocks are ~ut vulnerable during the wtIvity (rather than dark] ~ase. In ~ort of the original hypothesis the u~del produces reurophysiologlcal deregulation (schizo~~renia?) when an individual possessing the “r~cturnal scl~na” tries to be day—active and, In effect, tries to live a diurnal life with a r~cturnal brain.

i~     ~UC1ION OF ~IL~’ S PLAY B~AVICI~: A CROSS-CULTURAL STUDY

Lisa A. Feiernen

Depertient of Psychobiology, University of Calif orrLia, Santa Cruz.

~       while a student in resi~ice at Forschungsstelle für Hun~nethologie

in der Max-Planck-Ges.el lscha.ft, Erling—Arx~ChS, ~I~3

‘flere are several theories about the function of play behavior:

(1)    ritualization of aggression, (2) drive expression, (3) social bonding, (4) establish &inlnance rankings, (5) practice separating behavior fran e~tions, and (6) role rehearsals. Data ~‘ns collected on dyalic interactions of children within six cultures (Ym~n~, Hints, Trobiand, Eipo, aqi, and !Kung). All mterial ~‘s taken fran the Mex­Planck-Gessellschaft film archives of unstaged &~ unedited social interactions. “Hits during play” (including rough and tuntle play)

It

 

along with “~ysical contact during real aggressive encounters ~re the parameters studied. ~ data s1~i a negative correlation bet~en “hits during play” and “~ysical contact during real w~reasive encounters” within a single culture. ~ children’s nDtor patterns used in “hits during play” paralleled culturally-stereotyped a±i.lt behaviors n~re than the children’s n~tor patterns used during real aggressivity. AL~ (YarxsIHn~) culture with the nest “hits during play” ~.as also the culture with the least nunter of “p~iysical contacts during real ~ressive e-icamters”. “Hits during play” rarely observed azm,ng the TrobIand Islar~rs, the culture with the highest ni~er of “physica.l contacts during real aggressive encounters.” ¶Ibese findings are discussed within the context of the six theories about the function of play.

 

 

 

 

The Evolutionary Perspective in Murray Bowen’s Family Theory

 

Stephanie J. Ferrera, M. S. W.

100 Forest Place, 410

Oak Park, Illinois 60301

 

Georgetown psychiatrist Murray Bowen views the family as an “emotional system.” He uses the term emotional in the Darwinian sense to describe deeply—rooted instinctual forces which the human has in common with other forms of life. The term system defines the family as an inter­dependent unit, an organism which is more than the sum of its parts. Individual members shape the system, and the system as a whole shapes the functioning of its members.

Bowen’s “scale of differentiation” describes the range of variation among humans in the degree to which automatic emotional reactivity governs behavior. Better differentiated individuals, those more able to maintain autonomy and self—regulation at the same time they are actively connected to the family, contribute more to the functioning and direction of the unit. Poorly differentiated members function more in reaction to the system and are more vulnerable to becoming compromised or symptomatic under stress.

Bowen also describes the “adaptive mechanisms” or patterned behaviors which have evolved to maintain the stability of the family under stress. These patterns are comparable to behaviors observed in mammalian families which are ancestral to the human family.

Evolution of Gender Differences in the Brain: Implications for the Ethology of

intimacy.

Helen Fisher

Department of AnthropolOgY, American Museum of Natural History

Address:    65 East 80th Street, New York City, New York, 10021

 

Data suggest three general male/female differences ~fl the brain. On average, ~ males exhibit greater spacial acuity while females display greater verbal skills; males are more aggressive while females are more nurturant; males exhibit better gross motor coordination while females display superior fine motor abilities. These dimorphisms are seen incipient in comon chimpanzees; archeological data suggest they evolved in the hominid dade by 2 my BP as adaptations to the 3~avenging/hufltiflg/collecting lifeway. This paper traces the evolution of gender differences in the brain and proposes that these dimorphismS selected for gender—specific patterns of intimacy: Women derive intimacy from face—to—faCe talking while men derive intimacy from participating in side—by—side spacial activities, such as observing and playing sports. This gender dimorphism in intimacy produces misunderstandings between the sexes.

 

 

 

A Theory of Moral Sentiments

by

Robert H. Frank

Professor of Economics

Cornell University

 

Abstract

The prisoner’s dilemma has long occupied the attention of biologists, economists and other behavioral scientists. The identifying feature of this simple two-person game is that, although both players do better when both play cooperatively than when both play selfishly, each player does best by playing selfishly.

Recent research has focused on the tendency for cooperation to emerge when the same players confront one another repeatedly. (Axelrod, 1984; Trivers, 1971.) The tendency to cooperate is well documented but, contrary to all received theory, it does not depend heavily on repeated interaction: Cooperative play is the norm even in many one-shot prisoners’ dilemmas. This observation raises profound and troubling questions about conventional theories of both rational choice and evolution by natural selection. The objective of my research has been to explore how cooperation in one-shot prisoner’s dilemmas might be sustained in an environment in which survival depends only on relative material payoffs.

My starting point is the well-documented observation that cooperation in such dilemmas is based not on rational calculation but on emotional predisposition. I then investigate the conditions under which people who are thus predisposed will survive in a competition with opportunitists for scarce material resources. My principal finding is that survival of cooperators requires a statistically reliable signal that enables them to identify one another. Given such a signal, it is possible for cooperators to interact selectively with each other; in the process, they avoid exploitation by opportunists, and at the same time reap the higher payoffs associated with cooperative play. A blush may reveal a lie and cause great embarrassment at the moment, but in circumstances that require trust, there can be great advantage in being known to be a blusher. A corollary finding is that if the signal that identifies cooperators is costly to observe, the equilibrium population will always

include a mix of both cooperators and opportunists. Just as it would not p~y 10 111S1311 security devices in a neighborhood in which no burglaries were ever committed, it would not pay to scrutinize for synptoms of trustworthiness in a population in which everyone was trustworthy. The result, in both cases, is to create an opening for opportunists. Once they become sufficiently numerous, it will pay cooperators to incur the costs of scrutiny, which in turn will limit further expansion.

TOWARDS AN EVOLUTION-BASED CLASSIFICATION OF PSYCHOLOGICAL

DISORDERS

Kalman Glantz & John Pearce

49 GranIte St., Cambridge, MA 02139

 

The problems with DSM—III—R, the classification system now used by mental health providers, are well—known. An alternative approach based on evolutionary psychology seems promising. Since behavior is the product of psychological mechanisms crafted by natural selection to promote inclusive fitness in a particular environment, It seems logical to assume that the malfunctioning of these mechanisms, whether due to genetic defects or to a change in the environment, is the proper study of clinical psychology/psychiatry. A set of mechanisms is proposed, Including pathologies of reciprocity; status; mating behavior; sexuality; assessment of danger; empathy (assessment of the feelings, motivations and goals of others); integration; relationships; attention; inter— hemispheric transfer; models; etc. The evolutionary relevance of each mechanism is outlined; and the clinical content of the categories Is Illustrated. Some unresolved problems with the proposed system are discussed.

 

 

 

 

 

 

Laughter:          Communicative signal with genetic links Russell Gardner, Jr.

 

Department of Psychiatry and Behavioral Sciences, University of

Texas Medical Branch

Mailing:          1.200 Graves Building (D29), UThB, Galveston, TX 77550

 

A task of evolutionary biology as it relates to behavior includes decyphering genomic determinations of communicative behavior. A method of doing this may include behavioral and genetic investigations of forms of mental retardation in which there are known genetic deletions on the one hand and distinctive communicative signals on the other. Angelman’s or the “happy puppet” syndrome is a little known form of profound mental retardation in which there is a deletion at chromosome 15q11—l:3 in 30~ of cases. Afflicted individuals are called “happy puppets” because although they never learn to talk (they seem disinterested in learning to speak), they do laugh much of the time. They are also ataxic and their posture includes upwardly turning their palms. Their tongues protrude. The same genetic deletion occurs in many persons with Prader-willi syndrome (characterized by hypotonus at birth, small hands, feet, genitals and stature along with incessant eating and consecjuent

except (according’ to recent research with RFLP and DNA Probe analyses) that parents of the Opposite sex COntribute the chromatid with missing DNA. In Angelmanus syndrome the mother’s chromosome is the source of the missing material and in Prader...wiii~, the father’s.

Bigness:       perception, appraisal, and exhibition R Gardner and C Reichelt

 

Dept Psychiatry & Behavioral Sciences, UTMB, Galveston, TX

Wadena, Minnesota

Mailing address: 1.200 Graves Building, UTMB, Galveston, TX 77550

 

Potential prey adeptly perceive the “bigness” of a predator. For example, “eye spots,” as in fish and butterflies, ward off predators who desire themselves to avoid being prey. Avoidant animals analyze the distance between such eye spots as an index of bigness.

Within species, comparison of the bigness of other conspecifics to one’s own size, and exhibition of bigness towards other conspecifics, entails much calculation for any individual. Mate selection, territorial defense, as well as dominance and other alpha behaviors key partly on size-related behaviors and perceptions.

Pervasiveness of bigness perceptions and exhibitions point to an area of investigation for neural congruities across—species. For example, exhibition of different postures are encoded within the human nervous system. That such may be coded deeply within a midbrain-basal ganglia system may be indexed by the upright extended posture of a patient on excess amounts of L-dopa (the precursor of dopamine) versus the bent flexed posture of the person with Parkinson’s disease (stemming from dopamine deficiency). Examples where bigness exhibition systems may operate include the upright posture of a euphoric manic (vs the slumped posture of a depressed person), or the posture of the charismatic leader (vs that of the loser).

 

 

 

 

 

 

Across-national study of subordination and depression

 

R Gardner, L Sloman, D Wilson, K Glantz, S Heisel, J Pearce, and

SW Itzkoff

 

Institutions:               University of Texas, Clarke Institute, University

of Toronto, Harvard University, Smith College, private practice

Cities:          Galveston, Toronto, Boston, Cambridge

Mailing address: 1.200 Graves Building (D29), UTMB, Galveston, TX

 

The above authors (with interested parties from abroad who

could not be there - JS Price, P Gilbert & FX Plooij) have begun planning a study of human groups that would investigate whether subordinate self—perception along a submission/self-assertion dimension would correlate with the psychiatric diagnosis and/or self-report of depression measured on another dimension. This study stems from an across-species hypothesis that neural (and other body) mechanisms exist in common for depression (in humans)

on the one hand and very low ranking (in many species) on the other. Congruent findings across—cultures would attest to the postulated correlation being more basic than non-congruence,

Data-sources ultimately will Iflclude multiple nationalities and different languages. In its first meeting (3/25/90) at McLean Hospital in Boston, the group determined general goals Which included submission of an abstract to HBES to Publicize the goals of the research and to recruit interested participants The group is working on the development or adaptation of instruments methods of conducting and integrating pilot work in our local settings and the overall organizatj0~ of how larger scale data collection and analysis might work. We hope at HBEs to present the results of the first two Planning meetings.

MENSTRUAL AND OVARIAN SYNCHRONY AMONG THE LESE, ZAIRE Harrigan, A.M., G.R. Bentley, and P.T. Ellison

 

During an eight-month field study of the reproductive ecology of Lese horticulturalists in Zaire, longitudinal data were collected on menstrual onset from 48 women, totaling 178 completed cycles. Timing of menstrual onset was analysed for synchrony among the following groups of women: co­wives, co-villagers, relatives, and friends. Mean onset of menstruation was determined for each group and compared to a Lese control group of randomly-chosen, age-matched individuals. No significant differences were found between any of the groups. If synchrony is at all relevant to female reproductive function, we suggest that ovulatory synchrony may be a more revealing measure because of its more direct implications for reproduction. Ovulatory synchrony among the Lese can be reconstructed using approximate ovulation dates based on progesterone and estradiol profiles from salivary steroid analysis. We discuss the implications of these findings for understanding the evolution of human reproductive biology.

 

 

 

 

 

 

 

 

 

 

ASSOCIATIONS AMONG SOCIOECONOMIC RESOURCES AND REPRODUCTIVE VARIABLES IN A

SAMPLE OF OLDER RESEARCH VOLUNTEERS

 

Elizabeth M. Hill, Ph.D.

University Qf Michigan Alcohol Research Center, Department of Psychiatry

400 E. Eisenhower Parkway, Ann Arbor, MI 48104

 

The relationship between resources and reproductive success is of interest because of its relevance to adaptation in current behavior. Data from ongoing studies at the Alcohol Research Center were analysed for evidence of a positive relationship. Volunteers were questioned about family, marital, and socio­economic variables during a routine screening interview for studies of alcohol and aging. Those over age 40 were included in the analysis. The average respondent was about age 65 with 2.3 children, the first of whom was age 39. For men, there was a moderate positive effect of socioeconomic resources on the number of children fathered (Spearman correlations of about .25 - .35). Men with no children were typi~­cally at a clerical occupational level and had a current indMduai income of $1 0-15,000, while men with four or more children were typically administrators whose current individual income was $30-50,000. For women, there were no significant relationships of number of children with most resource measures, including the primary spouse’s occupational prestige, except for a strong negative effect of children on one s own income. The sample of those aged 60 or over was examined for relationships between resources and number of grandchildren (mean = 2.6). About 75% of people had at least one child who was married or cohabiting. Household income, but not other resource variables, showed a significant positive relationship with numbers of grandchildren for men, but there were no significant associations for women. Also presented are the effects of two variables that measured economic conditions in childhood

and improvement compared to one’s parents. Resufts are ~n~aredIo previoug t~ot~g on thn ~ reproduction relationship, which have generally focussed on married Couples.

HIllard Kaplan

Department of Anthropol~y

Univ. of New Mexico

Albuquergue,Ntl 87131

 

Abstru~t

iie~ur1no The Cmts of ChhltreerlrKJ in lralltIonal 54jflsistAnC~-tI~1 ~CEiflti~ A U~t fir

 

the Wealth Flows ~oothesls

 

A method is presented for measuring the total net caloric costs of raising chIle-en in traditional subsistence—based societies. This method is then used to calculate the costs of raising ctilkten In three socleties the Ache of Paraguay, the Machiguen~ and the Piro of Peru. The data show that in oil three societies offspring area net economic cost to parents even when the entire lifespan is considered. Since each of these three societies has h1~i fertility (Mean Total Fertility Rate = 7.3 lIve births), this Is strcmg eveldence against the prediction of the wealth flows hypothesis that offspring provide net economic benefits to parents In hi~i fertility, pro— demo~aphic transition societies.

 

 

Prepared for the Human Behavior and Evolution Society, Second Annual Meeting, Aug 16-19, 1990

 

 

 

 

 

 

PHENOTYPIC VARIATION AND CHAOS THEORY:

AN ARGUMENT FOR A DEVELOPMENTAL PERSPECTIVE

 

Kevin Kerber, M.D., Department of Psychiatry

University of Michigan, Ann Arbor, MI

 

 

From an evolutionary perspective, the hunt for a species-typical “human nature” must be reconciled with the genetic and phenotypic uniqueness of each individual. In order to integrate the effects on phenotype of both proximal and ultimate mechanisms, there must be the simultaneous understanding of both this uniqueness and this universality. In contrast with the prior view of species as

types” of more or less identical individuals (whose minor variations were of no consequence), Darwin saw the evolutionary significance of species as populations of unique individuals. This uniqueness is the result of the literally unrepeatable combination of genotype-environment interactions that shape individual phenotypes. Chaos theory offers a useful perspective by empba~i~in5 t1i~

unpredictability.. -and therefore the uniqueness..~f phenotyp!c Outcome This unPredictability of outcome arises in even simple systems where there is incomplete understanding of an individual’s starting conditions and of later interactions between multiple nonlinear influences on phenotype This suggests that Psychological mechanisms need to be Seen not just as universal, adapted parts of human nature but also from a developmental perspective, appreciating their varying individual manifestations and historical contingency.

Affect &S £ Proximate Signal for Fitn.ss-K*hiDiZiflg ~.havtor:

Why st.p’parents care less for their non-biological children

 

Katherine A. Khavar±, UCSF/ASU Psychology

                                      DouglaS T. Kemrick,           ASU Psychology

 

Correspondence:      K.A. Khavari. Langley Porter Psychiatric Institute-UCSF 401 Parnassua Ave San Francisco CA 94143

 

While social learning theory (e.g., Sarbin & Allen, 1968) vould suggest thai:

the experience of particular emotions should flow from the enactment of a giv•n social role, social evolutionary thinking leads to the hypothesis the’:

human affect serves as a proximate mechanism for adaptive behavior. Given dl survival-relevant challenge, an individual’s emotional response ii hypothesized to vary in intensity as a function of how seriously ‘rn fitness is challenged. Natural parents, for example, are predicted to experience hig~i levels of distressed affect when their offspring arm threatened physically by a third party. Step-parents. in contrast, are not expected to respond as intensely when their non-biological children are faced with the same danger. Role theory would predict that both types of parents will respond with high levels of intensity when their child is threatened, The social evolution prediction is supported in a. questionnaire study. The specific implications of ths5e data are discussed in the light of Daly and Wilson’s (1988a, 1988b) work on the high pr.v.l.nca of step-child homicide. A second prediction regarding gender diff.rCflCCB in affective respons. to sexual infidelity was not suppotted.

 

 

 

 

Increase of trisomy incidence with increasing maternal age does not result from competition between chromosomes

 

 

Raymond J. Kloss, M.D.

Randolph M. Nesse, M.D.

&nb