The First HBES Roundtable Seminar Series — October 29

HBES is excited to announce the first HBES Roundtable Seminar Series!

What: HBES’s Roundtable Seminar Series 
1st Topic: Beyond WEIRD, a decade later: Population diversity in the evolutionary study of human behavior. See also EHB’s Beyond WEIRD Special Issue.
Speakers: Clark Barrett, Dorsa Amir, Joseph Henrich, and Brooke Scelza

Moderated by: Coren Apicella

Date: Thursday, October 29
Time: 12 to 1:15 EST.

This series is an opportunity for HBES members to engage with experts on topics in the evolutionary behavioral sciences. Each virtual session will feature a panel of speakers answering questions from a moderator and live audience. Join us each month to discuss the big questions facing our field. Live sessions on Crowdcast are open to registered HBES members only, but a recording will be made publicly available on Youtube after the event. HBES members will be emailed with login information the week of each session. If you have any questions about this event, please contact the event coordinators at


See our new webpage to stay up to date on these events!


To attend the livestream, HBES members will need a password, which will be emailed to HBES members’ email accounts the week of each event. You can follow the Crowdcast account for additional updates and reminders.


What is HBES Doing About the WEIRD Problem?

By HBES Executive Council Members, Chris von Rueden & Coren Apicella


Evolution and Human Behavior (EHB) just released its September issue, which is devoted to highlighting ongoing research in the evolutionary social sciences that expands beyond WEIRD (Western, Educated, Industrialized, Rich, and Democratic) populations. This special issue, titled “Beyond WEIRD, a decade later: Population diversity in the evolutionary study of human behavior,” was edited by Coren Apicella, Ara Norenzayan, and Joseph Henrich and features articles on topics including evolutionary medicine, cooperation, leadership, morality, and developmental psychology.


This special issue reflects the broader commitment of HBES to diversity in research. When Debra Lieberman in 2018 became Editor-in-Chief of EHB (HBES’ flagship journal), one of her primary objectives was to organize a special issue on this topic, which she described as “highly desirable and well overdue.” Recently, in consultation with the journal’s editorial board, she has instituted policies to prevent “generic sample descriptions”. In his contribution to the special issue, H. Clark Barrett contends that researchers who use generic sample descriptions are implying, consciously or not, that “cultural identities do not matter for the conclusions being drawn”.


Now, authors who submit to the journal are required to fully describe their samples. For instance, authors are now asked to specify the geographic location from which their sample was drawn, how their data was collected (online or in-person), and any theoretically-relevant characteristics pertinent to the research study, such as religion affiliation, race/ethnicity, and gender identity (inclusive of non-binary options). And importantly, authors must also specify the source of the sample in their Abstract. Manuscripts that do not adequately describe samples will be returned to authors for revision prior to consideration.


Although EHB may fare better on inclusion of less WEIRD samples than many mainstream journals, particularly in psychology, there is still much more work to be done. In his contribution to the issue, H. Clark Barrett provides a bibliometric analysis of all 300 articles published in EHB in the last five years to assess “empirical representativeness.” This exercise revealed how contributions to EHB tend to be based on research with college students in the US, Europe, and East Asia or alternatively, with small-scale societies. This finding suggests that a broad swath of humanity remains under-represented. Akin to using college students, Barrett suggests that much cross-cultural research also relies on convenience sampling where the only justification provided is “this has never been studied in non-WEIRD people.”


This leads to another important concern raised in the special issue – the dichotomizing of WEIRD and non-WEIRD populations. In the introductory article for the special issue, Apicella, Norenzayan, and Henrich caution researchers against using WEIRD as a dichotomous construct. Such dichotomies, they argue, ignore the substantial variation that exists within and between populations. Paradoxically, perhaps, Apicella, Norenzayan, and Henrich note that the WEIRD acronym was chosen in part to de-exoticize less WEIRD populations. The acronym was meant to highlight the peculiarities of more WEIRD populations, that, in a global view, stand out.


This dichotomy also increases the likelihood that readers (and occasionally researchers) will fall back on inaccurate and harmful stereotypes when describing less WEIRD populations. We should avoid exoticizing less WEIRD populations in our own research, and we should avoid promoting research and popular articles that do so. Mistakes do happen though, even by the most well-meaning among us. For instance, an article that romanticized the Hadza people was shared recently on Twitter by HBES. The article was removed after several anthropologists and Shani Mangola, a Hadzabe activist and lawyer, highlighted its problems. As members of HBES, it is important that we continue to educate ourselves about these issues and halt the perpetual stereotyping of less WEIRD populations that has historically existed in cross-cultural research.


Moving forward, Barrett and Apicella, Norenzayan, and Henrich, and other contributors to the EHB September issue call for a more thoughtful and systematic pairing of research questions with the particular characteristics of different research populations. Other evolutionary social scientists have voiced similar sentiments. For a more in-depth discussion, see Broesch, Crittenden, et al. and contributors to a PNAS colloquium on psychological and behavioral diversity. These authors not only address selection of research populations, but also describe the shortcomings of cross-cultural comparisons when researchers do not consider culturally appropriate tests and protocols.


Perhaps of the utmost urgency is a greater consideration of the ethics of conducting cross-cultural research. Better communication with and involvement of research communities during study design, particularly those communities who historically have been marginalized, should be prioritized.


The September EHB issue, “Beyond WEIRD, A Decade Later: Population Diversity in the Evolutionary Study of Human Behavior,” offers some criticisms, but its contributors are also optimistic about the future of evolutionary social science. We agree that the methods and theory will only get better, and that is in part because of the disciplinary diversity of our community. In particular, the dialogue between anthropologists and psychologists has been, and we hope will continue to be, an engine at the heart of the creativity and productivity of HBES.


For those who are interested in hearing more about these topics, please tune in to HBES’ inaugural virtual roundtable discussion. This roundtable discussion, held on October 29, will focus on cross-cultural research in evolutionary science. Panelists include Brooke Scelza (UCLA), Dorsa Amir (Boston College), H. Clark Barrett (UCLA), and Joseph Henrich (Harvard). The discussion will be moderated by Coren Apicella (UPenn). Information on registration is forthcoming.


If you are interested in submitting a commentary related to the Beyond WEIRD special issue, please submit a 500-word proposal to Debra Lieberman ( by November 1, 2020. You will be notified by November 15 if your proposal is accepted. Completed commentaries will be due by December 15. Instructions for commentaries will be provided upon proposal acceptance. Please consult the special issue for detailed instructions.


— Chris & Coren

How Culture Shapes Who Hunter-Gatherers Prefer To Live With

By Kristopher Smith


What kind of people do you like to surround yourself with? If you’re like the participants in most psychology studies, you probably prefer to be friends with people who are trustworthy and generous. This makes sense; when the going gets tough, you want friends you can rely on to be there for you. It’s not difficult to imagine our hunter-gatherer ancestors, living in dangerous environments with scarce resources where help would often be needed, having similar preferences.


But the people who participate in psychology studies are not like most people, and on a number of psychological traits, are outliers from the rest of the world. In fact, most participants in the behavioral sciences are WEIRD: Western, Educated, Industrialized, Rich, and Democratic. For example, compared to populations from East Asia, WEIRD people have a more independent concept of self and value self-consistency more, and compared to subsistence populations, WEIRD people are more likely to offer fair offers and reject unfair offers in the ultimatum game.


And there’s reason to think WEIRD people differ on their preferences for generous friends, especially compared to hunter-gatherers. For example, hunter-gatherers have strong norms of food sharing, and these norms are often more important for determining whether a person is generous than their disposition to share. In such a situation, it may be more important to prefer a friend who brings back food in the first place, regardless of their willingness to share it.


While we cannot go back in time to see who ancestral hunter-gatherers preferred as friends, contemporary hunter-gatherers may provide some insight into how these conditions can shape social preferences. Of course, present-day hunter-gatherers are different from ancient hunter-gatherers in many ways, and depictions of them as the “natural state” of humans are problematic, ethically and scientifically. However, studies with hunter-gathers provide an opportunity to examine psychological variation in an environment without agriculture or its associated institutions.


In 2016 and 2019, I visited the Hadza, a group of hunter-gatherers living in northwestern Tanzania around Lake Eyasi. The Hadza live in small camps of about 20 to 30 adults and children, usually consisting of multiple unrelated nuclear families. These camps are highly interdependent, and members of a camp are expected to share food, childcare duties, and protection with everyone else. Camps move locations every six to eight weeks as local resources are used, and people within a camp can move to a new camp as they wish. That is, if a member of a camp is frustrated with her neighbors, she could walk to a new camp with more desirable campmates.


Along with a team of research assistants, I visited about a dozen camps in both years and took photos of all the adults. We used these photos to ask participants to rank their campmates on a number of traits, including who was the most generous, hard-working, and honest, who was the best hunter or gatherer, and who they would like to live with the most in a new camp. We used these rankings to examine whether who Hadza wanted to live with was better predicted by character traits, like generosity, effort, and honesty, or by their ability to produce food.


Research assistant Victoria Maghali interviews a participant about her campmates.


Coren Apicella and I found that, in 2016, it was the campmates who were perceived as the best hunters who were most desired as campmates, and those perceived as high on character traits were only weakly preferred. While this contrasts to the preferences observed in WEIRD people, it supports previous results with the Hadza. In a study mapping their social network in 2010, it was people who were more physically fit, which is related to hunting ability, that had the most social ties in their network, not people who gave more in economic games.


In 2019, however, the pattern reversed; Hadza participants had stronger preferences to live with campmates they perceived as being more generous, honest, and hardworking compared to campmates perceived to be the most productive. So, over a ten-year span, the Hadza increasingly preferred to live with more generous Hadza. Why the change over time? One possibility is that the Hadza are becoming increasingly exposed to the surrounding cultures, with more Hadza attending school, working jobs in local villages, and traveling further to larg towns in the past decade. In 2019, I had surveyed participants about their exposure and knowledge to non-Hadza culture. And, in fact, participants who had greater exposure had the strongest preference for campmates high on character traits.


“Hadza participants had stronger preferences to live with campmates they perceived as being more generous, honest, and hardworking compared to campmates perceived to be the most productive.”


Exactly why exposure to other cultures is changing who Hadza prefer as campmates is unclear. We hypothesize that as Hadza have more experience in situations without strong norms of helping and sharing, where how generous a person is less determined by norms and more by their disposition to help, Hadza learn to discern how generous a person is and prefer to interact with people they perceive as helpful. We hope to test this hypothesis and better determine how exposure is changing their social preferences in future research.


Our research reveals both similarities and differences between WEIRD people and hunter-gatherers in social preferences. Like WEIRD people, Hadza are choosy about who they would prefer to be around and such choosiness may have deep evolutionary roots, as chimpanzees and even cleaner fish have strong preferences of who they want to cooperate with. What traits Hadza choose their friends on though has historically differed. Hadza had preferred people who were more productive rather than more generous; however, their preferences seem to be changing over time, and quite quickly. The findings highlight how ecological and cultural conditions can shape human psychology and the importance of mapping the full extent of human psychological variation.


Read the paper: Partner choice in human evolution: The role of cooperation, foraging ability, and culture in Hadza campmate preferences


Beyond WEIRD Morality

by Mohammad Atari


A decade ago, Joseph Henrich, Steven Heine, and Ara Norenzayan published a landmark paper in Behavioral and Brain Sciences titled, “The weirdest people in the world?”. The cardinal argument of Henrich and colleagues was that there is an over-reliance on Western, Educated, Industrialized, Rich, Democratic (WEIRD) samples in psychological research. The term “WEIRD” rhetorically highlights the peculiarity of this population that largely dominates psychology samples. Henrich and colleagues suggested that much of what psychologists thought they knew about fundamentals of human cognition and behavior was probably only true of one small slice of human diversity on the planet. In fact, WEIRD people make up only about 12% of the world’s population and yet over 90% of the research participants in psychology. But while this celebrated paper (cited about every 12 hours since published!) provided an apt diagnosis of a pressing problem, there is a question of whether much has been done to address the problem, and where psychology has positioned itself to diversify its studied populations. A recent analysis published a decade after the WEIRD paper came out, investigated research samples in high-impact American Psychological Association (APA) journals (which often function to some extent as “gatekeepers” to their subfields), finding that 89% of the world’s population continues to be neglected.


The scientific community’s response to a lack of diversity in research samples cannot be limited to encouraging scholars from WEIRD societies to pack their bags and go study other cultures. Rather, a diverse and mature science must include a diverse group of scientists, who are both motivated and able to “ask non-WEIRD questions”. Diverse researcher perspectives and viewpoints are often associated with the generation of novel and higher-quality discoveries. Indeed, minority scholars have expanded psychological science in important ways. Fundamentally, studying diverse populations as the “other” populations (as opposed to studying diverse populations by diverse scholars) leads to what Douglas Median and colleagues called the “home-field disadvantage”.


The home-field disadvantage refers to the disadvantage inherent in research that takes a particular cultural group as the starting point or “standard for research”. Medin and colleagues argue that the home field is a serious handicap that pushes researchers toward thinking that the cultural group that differs from “us” has failed, where “failed” means not performing in accordance with “our” expectations. These authors suggest strategies to avoid the home-field disadvantage, including doing one’s best to study the phenomenon of interest on the terms of the culture being studied. For example, if one were studying cultural differences in emotions, it would be an erroneous practice to start with English emotion terms and attempt to look for their counterparts in another culture, as this presumes part of the very phenomenon one wishes to study.


Moral psychology, drawing on both the empirical resources of the social sciences and the conceptual resources of philosophical ethics, continues to suffer from both the “home-field disadvantage” (i.e., researcher diversity problem) and the “WEIRD person” problem (i.e., sample diversity problem). The current WEIRD state of moral psychology is in fact peculiar and unfortunate, given that cultural psychologists explicitly advocated for cross-cultural work in developing moral psychological theories. Most notably, Jonathon Haidt, working at the time with anthropologist Richard Shweder, called for culturally informed theories of moral cognition in the 1990s. Haidt and Shweder argued that moral appraisals differ substantially across individuals, cultures, and historical periods. For example, Shweder showed that in India, among Brahmans, it is “immoral” for a son to eat meat or cut his hair during the 10 days that follow the death of his father. Carol Gilligan’s now-classic critique of Kohlbergian moral psychology (which reduced morality to justice) asserted that people have two moral “voices,” or ways of talking and thinking about moral issues. It is now evident that Gilligan has won the argument for moral pluralism. Following up on a pluralistic notion of morality, Haidt and colleagues proposed the Moral Foundations Theory (MFT) which was developed in order to fill the need of a systematic theory of morality, explaining its evolutionary origins, developmental progressions, and cultural variations. Haidt and colleagues surveyed evolutionary psychology and anthropology, looking for moral concerns that were common across cultures. Five candidates were suggested for being the basic, evolutionarily-prepared psychological “foundations” upon which cultures construct their moral systems. Care, Fairness, Loyalty, Authority, and Purity are theorized to have solved adaptive problems over humans’ evolutionary history.


In the recent Evolution and Human Behavior’s Special Issue to mark a decade since the publication of “The weirdest people in the world,” Jesse Graham, Morteza Dehghani, and I examined moral foundations in Iranian culture. Privileged with a home-field advantage (being Iranian myself) and having access to Iranian samples, we expanded upon MFT’s theoretical line of reasoning. To be sure, simply calling Iran non-WEIRD is overly simplistic; a psychological analysis of a non-WEIRD culture must include a nuanced, descriptive probing of the studied population. Iran is geographically close to countries like Pakistan, Egypt, Azerbaijan, or Armenia, but is overall more developed than these countries. Using Muthukrishna et al.’s WEIRD cultural distances, Iran’s distance from the U.S. is comparable to Turkey and Armenia, while slightly greater than Japan’s distance from the U.S.


To better contextualize our claim that Iran is an extremely understudied culture in psychology, I searched the contents of Psychological Science, Associations for Psychological Science’s (APS) flagship journal. In the last three decades, zero articles have been co-authored by Iran-affiliated researchers. And, of course, in some papers, Iran is randomly mentioned to exemplify “political aggression” or “a country emphasizing gender inequality”. Hence, it is plain to see that the scientific community, at least in psychology, does not really know much about Iran’s psychology, that is, how Iranians think, what their values are, how they describe each other, or how they view other cultures.


In six studies (N=1945), we evaluated MFT using the Moral Foundations Questionnaire and followed up by building a bottom-up model of moral values. Our results suggested that the Persian Moral Foundations Questionnaire is not a highly valid measure for assessment of moral concerns in Iran. Our cross-cultural comparison suggested that Iranians’ scores on moral foundations cannot be reliably compared with their American counterparts as the two cultures differ in the pattern of responding to questionnaire items (regardless of their average endorsement of different foundations). Consequently, we turned to qualitative research to build a bottom-up model of moral concerns. Qualitative interviews revealed that in addition to moral concerns found in Western contexts, one construct is central in moral concerns in Iran. This construct, “Qeirat”, does not have a straight English translation, but is semantically close to “honor” and consists of guarding and protectiveness of female kin, romantic partners, broader family, and country. We found Qeirat to be highly correlated with Loyalty, Authority, Purity, Islamic religiosity, and mate retention behaviors. These results are consistent with prior works my collaborators and I did in mating psychology, showing that Qeirat is an important characteristic in mate selection preferences among young Iranian participants and mate retention behaviors in romantic relationships.


Qeirat was shown to predict important outcomes above and beyond the five moral foundations, religiosity, and even honor. So, we proposed Qeirat as an additional moral foundation. MFT theorists have explicitly welcomed new foundations to be added to their framework as methods and theory co-evolve in moral psychology. Specifically, with regard to addition of new foundations, Graham and colleagues rhetorically posited that they “do not know how many moral foundations there really are. There may be 74, or perhaps 122, or 27, or maybe only 5, but certainly more than one.”


“Qeirat values maintain intensive kinship networks which can function to keep resources in the group.”


We speculate that Qeirat values are particularly adaptive in Iran’s socio-ecology due to historically moderate-to-high prevalence of pathogens, slightly male-biased sex ratio, relative scarcity of environmental resources, especially in some southern regions, and perceived socio-political threats from some Western countries considering some historical events. Qeirat values maintain intensive kinship networks which can function to keep resources in the group. Ecological conditions that facilitate Qeirat values give rise to higher intrasexual rivalry for access to mates, sensitivity to sexual norm violation, and vigilance to guard current sexual partners, especially female partners. Evolution of Qeirat values both supports and enables tight kinship networks and group coalitions in which the risk of contact with pathogens is minimized, mate poaching is heavily penalized, resources are retained within the group, and societal norms are maintained.


We believe this research opens up new, interesting avenues for research in Iran and other countries. For example, socioecological predictors, geo-spatial distribution, cultural antecedents, emotional correlates, and interpersonal consequences of Qeirat are yet to be explored. Unveiling Qeirat as a central feature of moral cognition in Iranian culture and the development and validation of the 24-item Qeirat Values Scale have already stimulated discussions in popular media in Iran. We hope and expect to see more empirical research on Qeirat values as a new moral psychological construct across various cultural contexts. We believe that this work can be considered an effort in moral psychology (as well as cultural and evolutionary psychology) to tackle both the “home-field disadvantage” and “WEIRD person problem” at the same time.



Read the paper: Foundations of morality in Iran

HBES Solicits Nominations for 2021 Executive Council Election

Dear HBES members,


2021 will be a big election year for the Executive Council. We are therefore seeking suggestions for nominees for the following positions:

  • President of HBES
  • Member-at-Large (two positions available)
  • Student Representative (must be current graduate student through spring 2023)

Please use this elections form on the HBES website to submit up to three suggestions for any of the positions. In the comment section of the form, please be sure to indicate the First and Last Name of the person you are suggesting AND the specific position you are suggesting the person for (i.e., President, Member at Large, or Student Representative).


Suggestions for Nominees are due by December 1, 2020.


Elections Process:

  1. HBES community submits suggestions for nominees of particular positions, listed above.
  2. The Elections Committee of the HBES Executive Council will consider the HBES community suggestions and internal suggestions for positions.
  3. The Elections Committee will contact all nominees to confirm their willingness to serve if elected.
  4. The final selection of nominees for all positions will be shared with the HBES community in January 2021.
  5. HBES members will vote during February 2021. Your membership MUST be active to be eligible to vote. You can join or renew here.
  6. Results will be announced by the President of HBES
  7. New officers will assume their roles after the 2021 HBES conference.

Welcome to HBES 2021 Palm Springs!

As the hosts, we would like to invite everyone to the 32nd annual HBES conference in sunny southern California. The conference will be held at the Marriott Renaissance Hotel in downtown Palm Springs. Convenient to the Palm Springs international airport or a three hour drive from Los Angeles. The city itself boasts a great selection of restaurants, bars, and cultural activities as well as the Village Fest Artisan Night Market every Thursday evening. Located in the Coachella Valley desert region, Palm Springs is sheltered by the San Bernardino Mountains to the north, the Santa Rosa Mountains to the south, by the San Jacinto Mountains to the west and by the Little San Bernardino Mountains to the east. Lots of opportunities to explore all the desert has to offer from golfing to spa life, the Living Desert Zoo, and much more.


The conference itself will begin on Wednesday June 2nd and run through Saturday the 5th. In additional to the usual activities, welcome reception, BBQ, and banquet, we have an exciting line up of plenary speakers including a diverse range of topics from evolutionary biology, psychology, and anthropology. We’re pleased to have Bobbi Low, our 2019 Lifetime Achievement Award recipient as our Keynote Speaker. We’re looking forward to receiving abstract submissions for talks, symposia, and posters beginning in November of 2020. Look for announcements from HBES and our official Twitter (@HBES2021), and check out the conference website which will be updated in October with important dates, hotel reservations, and other information.


Don’t forget student members, HBES is providing assistance with hotel costs and information on this will be on the hotel reservation page.


Looking forward to seeing you all! Please remember to bring sunscreen and a hat!



Catherine and Jessica

2020 Margo Wilson Award Winner

In 2009, the Publications Committee of HBES initiated an annual award for the best paper in each volume of Evolution and Human Behavior, “The Margo Wilson Award.” The award carries a cash prize of $1,500, and the winning paper is chosen by the Editorial Board of Evolution and Human Behavior.


This year, the competition for this award was fierce. At the beginning of the year, the Editors to nominated their selections from the 2019 volume. About a dozen excellent papers were nominated. One rose to the top. The winner of this year’s Margo Wilson Award goes to Professor Daniel Conroy-Beam and colleagues for their paper entitled “Assortative mating and the evolution of desirability covariation.” Congratulations to Daniel and his entire team!


Conroy-Beam, D., Roney, J. R., Lukaszewski, A. W., Buss, D.M., Asao, K., Sorokowska, A., Sorokowski, P., et al. [105 others] (2019). Assortative mating and the evolution of desirability covariation. Evolution & Human Behavior, 40 (5), 479-491.

 Abstract: Mate choice lies close to differential reproduction, the engine of evolution. Patterns of mate choice consequently have power to direct the course of evolution. Here we provide evidence suggesting one pattern of human mate choice—the tendency for mates to be similar in overall desirability—caused the evolution of a structure of correlations that we call the d factor. We use agent-based models to demonstrate that assortative mating causes the evolution of a positive manifold of desirability, d, such that an individual who is desirable as a mate along any one dimension tends to be desirable across all other dimensions. Further, we use a large cross-cultural sample with n = 14,478 from 45 countries around the world to show that this d-factor emerges in human samples, is a cross-cultural universal, and is patterned in a way consistent with an evolutionary history of assortative mating. Our results suggest that assortative mating can explain the evolution of a broad structure of human trait covariation.

A Letter from the Editor, Deb Lieberman

Dear HBES Members,

It has been a busy summer at Evolution and Human Behavior and I am pleased to provide you with several updates.


EHB Special Issues

Currently at EHB, we are working on the publication of two special issues. The first special issue, organized by Joe Henrich, Coren Apicella, and Ara Norenzayan, examines recent efforts to expand evolutionary social science research beyond WEIRD societies. The Beyond WEIRD special issue will be the next issue published (issue 5, 2020). The second special issue, organized by Willem Frankenhuis and Dan Nettle, is on Life History Theory and will be the 6th and last issue of 2020. In each issue’s Editorial/Introductory article, there will be details regarding how to submit commentaries—a feature I’d like to continue with each Special Issue published at the journal. I would like to take this opportunity to thank all of the Editors of both special issues for their hard work in pulling together excellent panels of papers. These special issues advance an important goal of the journal, which is to foster discussion and debate of scientific ideas as they relate to human evolutionary science. Thank you again!


EHB Reproductions

We are proud to announce a new article format at EHB called EHB Reproductions. EHB Reproductions report on efforts to replicate empirical research previously published in EHB. Reproductions follow the original methods and procedures to create conditions under which the original hypotheses can be tested. Deviations with respect to participants, materials, procedures, and analyses will be evaluated on a case-by-case basis. In general, though, researchers should attempt to use the same materials, procedures, and analytical techniques as employed in the original article, and, while I think this goes without saying, authors of original articles are encouraged to provide all necessary materials for successful attempts at replication.


An EHB Reproduction includes an Abstract of 250 words. The Introduction should identify the paper being replicated, the hypotheses being tested, the rationale for replication, the justification for the methods (including statistical power), and the main conclusions of the current work. The Introduction and Discussion should be no more than 1000 words combined. (The original article should have done the literature review and theoretical heavy lifting mostly freeing Reproductions from this task.) There is no word limit for Methods and Results, but authors are encouraged to be succinct. In the Methods, authors should be clear regarding the sample used, and any methodological or analytical deviations from the original article with justification. Ideally, references should be limited to around 10. Titles should conform to the following: “EHB Reproduction: Author (et al.), Date”. EHB Reproductions will be evaluated based on quality, not outcome. Authors of the original article will be offered an opportunity to respond to the replication effort in a commentary. Currently, EHB Reproductions are limited to empirical articles. Conceptual replications, including modeling papers, should be submitted as Research Reports.


Updates on Sample Description

In an effort to provide greater detail on samples reported in Research Reports and EHB Reproductions, the submission process will soon contain information regarding how to describe samples in both the Abstract and Methods. The Editorial Board is currently finalizing these instructions and we will post all updates to the online Guide to Authors.


Updates on Database and Stimuli availability

As a general policy, EHB will now require researchers during the submission process to provide access (via a link to an online repository or via supplementary materials) to anonymized datasets (when appropriate) and, when feasible, stimuli used to carry out the reported research.


Updates on Tables and Figures

This might seem trivial, but to facilitate peer review, we now ask that all tables and figures be embedded in the text of the submitted manuscript in their appropriate location in addition to being uploaded as separate files. (It’s the little things that matter.) I think that’s it for updates.


Have a safe and healthy start to the new school year,

Deb Lieberman, Editor-in-Chief, Evolution and Human Behavior

HBES Volunteer Coordinators Needed

We are looking for 2-3 postdoctoral researchers or graduate students to organize a new HBES Virtual Roundtable Discussion Series. Responsibilities include organizing, promoting (in coordination with the Communications Officer), and introducing each event. This is a great networking opportunity and comes with free HBES membership.


Interested persons should send an email to Coren Apicella and Chris von Rueden by August 15th.

Change in Hormonal Contraceptive, Change in Heart?

by Juliana French & Andrea Meltzer


140 million. That’s how many women world-wide are estimated to use hormonal contraceptives such as The Pill. The main function of hormonal contraceptives (and a leading reason for why so many women use them) is to decrease the likelihood of conception. But through administering synthetic hormones to achieve protection against unwanted pregnancy, hormonal contraceptives incidentally alter a myriad of other physiological and psychological processes. In a recent paper, we examined the extent to which hormonal contraceptives may alter processes important for maintaining satisfying relationships, such as sexual satisfaction.

Sex is a central feature of adult romantic relationships, which is reasonable considering the adaptive value sex has for reproductive success. It is therefore not surprising that frequent and satisfying sex plays an important role in the maintenance of people’s long-term romantic relationships. Nevertheless, one of the most common side effects of hormonal contraceptives—an evolutionarily novel medical advancement—is decreased sexual desire among women who use them.

Hormonal contraceptives are therefore, by definition, an evolutionary mismatch. A classic, easy-to-digest example of an evolutionary mismatch concerns modern food availability. Humans have an evolved tendency to seek highly caloric foods because this would have been adaptive in our evolutionary history when such foods were scarce. In 2020, however, this evolved tendency may lead you to crave chocolate chip cookies and fast food. When not kept in check, these (once adaptive) cravings contribute to modern rates of obesity. Similar to the abundance of highly caloric foods in our modern environment being mismatched to our evolved psychology, hormonal contraceptives may be mismatched to our evolved relationship processes, explaining, at least in part, some relationship dysfunction such as sexual dissatisfaction.

So, now you may be wondering, “although hormonal contraceptives help to prevent unwanted pregnancy, are they harmful for my relationship?”

Not so fast – there’s more to the story.

A recent study suggests that whether a woman uses a hormonal contraceptive may be less important for her relationship than whether she changes her hormonal contraceptive use after relationship formation. Imagine one woman, for example, who was not using a hormonal contraceptive when she met her partner but decides to start using The Pill after they have been together for a little while (perhaps because she is likely to engage in relatively more frequent sex and doesn’t want to become pregnant). Imagine another woman who was using The Pill when she met her partner but decides to discontinue using hormonal birth control at some point in her relationship (perhaps because she and her partner are trying to become pregnant).

Hormonal contraceptive use that differs from a woman’s use when she met her partner is called hormonal contraceptive incongruency. Notably, many women become hormonal contraceptive incongruent at some point during their ongoing, long-term relationships. Moreover, because many women begin and discontinue hormonal contraceptives multiple times in the course of a relationship, they repeatedly fluctuate between being congruent and incongruent. Are women less sexually satisfied during those times when their hormonal contraceptive use is incongruent (compared to congruent) from their use at relationship formation? This is exactly the question we sought we answer.

We tested whether such within-person changes in hormonal contraceptive use that results in incongruency is associated with decreases in sexual satisfaction. To do this, we asked 203 heterosexual, newlywed wives if they were using a hormonal contraceptive when they began dating their husbands. Then, at the start of their marriages and again every four to six months for up to four years, those wives (a) completed a measure of sexual satisfaction and (b) reported whether they were currently using a hormonal contraceptive. Results demonstrated that wives reported lower sexual satisfaction at times when their hormonal contraceptive use was incongruent with their use at relationship formation compared to times when their hormonal contractive use was congruent with their use at relationship formation.


Wives reported lower sexual satisfaction at times when their hormonal contraceptive use was incongruent with their use at relationship formation


There are two ways to be incongruent with respect to hormonal contraceptive use, however. Whereas some women do not use hormonal contraceptives when they meet their partners and become incongruent when they begin using them, other women use hormonal contraceptives when they meet their partners and become incongruent when they discontinue their use. Is one form of incongruency more strongly tied to decreases in sexual satisfaction than the other? The short answer is, no. In our data, changes in sexual satisfaction that were associated with incongruency did not differ for wives who were incongruent by “starting” hormonal contraceptives after relationship formation versus those who were incongruent by “discontinuing” hormonal contraceptives after relationship formation.

These findings suggest that simply using a hormonal contraceptive may not necessarily increase one’s risk of experiencing sexual dissatisfaction in a relationship. Rather, it is hormonal contraceptive incongruency—either beginning or discontinuing the use of hormonal contraceptives after relationship formation—that seems to be associated with future sexual problems.

This work represents an important methodological advancement for research examining the implications of hormonal contraceptive for romantic relationship processes. Although others have previously demonstrated associations between hormonal contraceptive incongruency and relationship processes (for example, relationship satisfaction and jealousy), this paper is the first to do so using a longitudinal design and within-person analyses. Cross-sectional studies have sometimes failed to detect between-person effects of hormonal contraceptive incongruency, and—indeed—when we examined our data using between-person analyses at baseline we also did not detect differences in sexual satisfaction between women who were congruent versus incongruent. Crucially, the longitudinal method and corresponding analyses that we conducted in this paper enabled us to statistically separate those non-significant between-person differences in incongruency from the key significant within-person changes in incongruency that are central to the underlying phenomenon.

We see this as a fruitful starting point for many future research questions. For example, is changing your type of hormonal contraceptive—perhaps by either switching from one brand of The Pill to a different brand or to a different hormonal method such as The Patch—also a form of incongruency? And, if so, are these other potential forms of incongruency also detrimental to relationships?

Without having the longitudinal data to answer these questions, we can only speculate. It seems probable that, yes, there are likely multiple forms of hormonal contraceptive congruency. But the extent to which other forms of incongruency may impact relationship outcomes, such as sexual satisfaction, likely depends on how different the incongruency-related changes actually are. That is, changing from a progestin-only pill to a different progestin-only pill is less of an incongruency than changing from a progestin-only pill to a combination (estrogen and progestin) pill, and the latter is still less of an incongruency than discontinuing hormonal contraceptives altogether.

When women discuss birth control options with their medical doctors, the conversation often revolves around common side effects, such as weight gain, headaches, mood changes, and decreased libido (to name a few). Relational side effects that may occur as a result of changes in hormonal contraceptive use, such as decreases in sexual satisfaction, are less-often (if ever) considered or discussed. There are many factors that contribute to sexual satisfaction—for example, how attracted you are to your partner (which, by the way, hormonal contraceptives may also alter)—and our recent research suggests that hormonal contraceptive incongruency is one such factor. Given the adaptive significance of long-term relationships for humans, it is paramount to understand how modern novelties such as hormonal contraceptives can impact relationship processes and stability.



Read the paper: The implications of changing hormonal contraceptive use after relationship formation