Job. Opening: Chair of Psychology, ASU

Arizona State University, a leading public research university that is rated first in the U.S. for innovation, seeks a dynamic, forward-looking chair for the Department of Psychology, with a concurrent appointment as a tenured Professor. The anticipated start date for this position is July 1, 2023.

See the full ad and apply here!

Director (Full Professor) Position at the School of Human Evolution and Social Change (SHESC)

The College of Liberal Arts and Sciences at Arizona State University (ASU) invites applications for the position of Director of the School of Human Evolution and Social Change (SHESC) with a concurrent appointment as a tenured Full Professor. 

SHESC Director Job ad!

Apply here!

Two tenure-track positions in Developmental Psychology at Oklahoma State University

DEPARTMENT OF PSYCHOLOGY, OKLAHOMA STATE UNIVERSITY is seeking outstanding scientists to fill two full-time, Assistant Professor, tenure track positions in the area of Developmental Psychology beginning August 2023. The Department is seeking one candidate for each of the following areas of specialization: (1) cognitive development with a focus on infancy or childhood; and (2) inequality as related to developmental psychology, broadly defined (e.g., economic disparities, social inequalities, psychology of fairness or morality). Candidates are expected to have a strong background in and dedication to scholarly activity, and to interact well with colleagues and students. They are expected to establish a vigorous, high-quality research program, to be or have potential to be internationally-recognized in their field, and to attract and mentor high-quality graduate students. We welcome applications from candidates with backgrounds in developmental psychology or closely related fields. Scholars with marginalized identities, including women, gender, and sexual minorities, racial and ethnic minorities, rural, first-generation, immigrant or non-U.S. scholars, scholars who experienced economic disadvantage, scholars with disabilities, and any other scholars underrepresented in psychology, are encouraged to apply.

The Department includes a strong Developmental Science cohort with expertise in cognitive development, social and emotional development, neurobiological development, and pediatric psychology. Candidates would also have access to the OSU Brain Initiative,, a growing interdisciplinary neuroscience collaboration at OSU that includes fMRI research capabilities. The Psychology Department has a shared laboratory space with facilities and equipment to support faculty exploring genetic and endocrine contributions to behavior. Competitive salary and start-up funds are available.

Candidates will be expected to serve as a research mentor for doctoral students, to supervise undergraduate research, and to provide quality classroom instruction for both graduate and undergraduate courses. Typical teaching load is two courses per semester. A successful faculty candidate should be willing to teach from a multicultural perspective and should be willing to mentor ethnically, racially, and socioeconomically underrepresented students. Diversity is a core value of the Department of Psychology and we are committed to the recruitment, retention, and success of diverse students. See:

The Department has 25 full-time faculty and offers Ph.D. degrees in experimental psychology and clinical psychology. The experimental program has concentrations in Developmental, Comparative-Neurobiological, Cognitive, and Social-Personality. The clinical program, continuously APA-accredited since 1971, is based on the clinical science model of training and is a member of the Academy of Psychological Clinical Science. The Department offers training to a diverse graduate and undergraduate student body (30% minority enrollment) of approximately 60 doctoral students and over 1000 undergraduate majors. The Department has faculty in Tulsa who teach and do research on the OSU-Tulsa campus. Applicants are encouraged to visit the Department website at

Oklahoma State University, home of the Cowboys, is a top-ranked public land-grant research university, located in Stillwater, OK, approximately 70 miles from the major metropolitan areas of Oklahoma City and Tulsa. Among the most geographically diverse states, Oklahoma has 11 distinct ecological regions in its borders—more per square mile than in any other state – and is

home to fifty-one state parks, six national parks or protected regions, two national protected forests or grasslands, and a network of wildlife preserves and conservation areas. There are currently thirty-nine recognized tribes with headquarters in Oklahoma and twenty-five Native American languages are still spoken here. See for more information. Stillwater is a smaller, welcoming city centered around the University, with approximately 50,000 full-time residents. Stillwater public schools were recently selected as one of the “100 Best Public School Systems in America,” and the city has excellent affordable housing. Faculty in the department also live in Oklahoma City and Tulsa.

For full consideration, application materials must be received by October 1, 2022. However, applications will be accepted until the position is filled. Applications should include a cover letter, research and teaching statements, vita, reprints/preprints of representative research, and summary of course evaluations/evidence of teaching excellence. The application portfolio, compiled as a single PDF file, should be uploaded to the application portal at In addition, candidates should arrange for three letters of recommendation to be sent via email to Dr. Jennifer Byrd-Craven, Chair, Developmental Psychology Search Committee at Questions about the position should be directed to Dr. Byrd-Craven.

Oklahoma State University, as an equal opportunity employer, complies with all applicable federal and state laws regarding non-discrimination and affirmative action. Oklahoma State University is committed to a policy of equal opportunity for all individuals and does not discriminate based on race, religion, age, sex, color, national origin, marital status, sexual orientation, gender identity/expression, disability, or veteran status with regard to employment, educational programs and activities, and/or admissions. For more information, visit https:///

Evolutionary Anthropology Postdoc Position

The University of Missouri Department of Anthropology seeks a scientific anthropologist specializing in human-environment dynamics, including human evolution and behavior for a 2-year postdoctoral position. The position is sponsored by the University of Missouri’s Preparing Future Faculty—Faculty Diversity (PFFFD) Postdoctoral Program, which is designed to prepare scholars for tenure-track faculty positions at the University of Missouri and elsewhere. The stipend is $60,000 per year plus benefits.

More information about the PFFFD program is available at The application deadline is September 30, 2022. The ideal candidate will complement our integrative study of Human Adaptation, Ecology, and Evolution. The area of specialization is open and can be, but is not limited to, cooperation and conflict, epidemiology, cultural continuity and variation through time, evolution of culture and intelligence, human interactions with plants and animals, life history and child development, religion, gender relationships, social structure and inequity, and hominid evolution. Research approaches can include but are not limited to demography, ecological and environmental anthropology, ethnobiology, archaeometry, human behavioral ecology, cognitive archaeology, genetics, human variation, and biomedical anthropology. MU’s Anthropology Department has long been recognized as a leading anthropology program among departments with a focus on the scientific study of relationships among culture, behavior, health, human biology and evolution, both throughout the present world and through prehistory. We have an internationally recognized program in these areas, and we seek a strong scholar to build on our strengths.

Contact: Rob Walker –

The 4th Brazilian Meeting on Evolution of Human Behavior

The 4th Brazilian Meeting on Evolution of Human Behavior is an international conference between the 17th and 21st of October 2022. The event will be held in English, with the exception of 11 basic and advanced short courses aimed at undergraduate and graduate Brazilian students, held by researchers from all over Brazil in Portuguese.

  Next, the congress will consist of 5 plenary talks: Dr. Edward Hagen (USA), Dr. Maryanne Fisher (Canada), Dr. Justin Mogilski (USA), Dr. Ana Maria Fernandez (Chile), e Dr. Dennis Werner (Brazil). Some of the invited speakers will further participate in a symposium specifically on sexuality from the evolutionary perspective.

Another highly important symposium aimed at feminist perspective in evolutionary psychology will be held by a representative of the Feminist Evolutionary Psychology Society, together with the Brazilian collective “Maria Emília – (R)evolutionary Women”. It will also include the discussion about the importance of women on the evolution of bipedalism. Another symposium about Parental Investment will include researchers from Federal University of Espírito Santo and University of São Paulo. Finally, a team of professors from the University of São Paulo will offer a symposium on Comparative Study of Development, focusing on environmental effects.

Find out more about our speakers and symposia in the tabs above. The conference will be further divided into approximately five thematic oral sessions and one poster session. Thus, consider submitting your presentation, be an active part of this program and let everybody know about your research!

The venue, Sao Paulo, is the largest city in South America, offering a taste of all of Brazil in one place, with its cosmopolitan life, unforgettable cultural events, enormous gastronomic variety, all kinds of museums, aquarium, zoo, parks, theaters, municipal markets, historical center and skyscrapers, and even some indigenous cultures.

Learn more here!

Thanks for a Great HBES 2022!

HBES 2022 was a success!

Many thanks to:
Our hosting platform: ohyay
The hosting committee: Leif Edward Ottesen Kennair (Chair), Norman Li, Jaroslava Varella Valentova
The program committee: Bernhard Fink (Chair), Kelly Asao, Khandis Blake, Michelle Escasa-Dorne, Katrin Schaefer, Joseph Manson, Joshua Tybur
The volunteers: Tara DeLecce, Tiffany Lussier, Saeed Rezvani-Nejad, Per Helge Haakstad Larsen, Angelica Nascimento de Oliveira, Caio Silva, Lynn Tan, Kane White, Bernardo Ubaldo Seixas, Andreza Souza Tavares
The fantastic keynote and plenary speakers: Peter & Rosemary Grant (keynote), Jan Willem van Prooijen, Anne Pusey, Cas Soper, Deb Lieberman
And every other speaker and presenter!

Catch up on the HBES 2022 talks on our OSF site

Congratulations to our 2022 Organizational Awards Winners

Early Career Award: Damian Murray (Tulane University)
Lifetime Achievement Award: Douglas Kenrick (Arizona State)
Margo Wilson Award: Stella Gerdemann (Leipzig University) & Annie Wertz (Max Planck)
Read here

Congratulations to our 2022 Conference Awards Winners

New Investigator Award: Summer Mengelkoch (Texas Christian University)

Postdoctoral Award: Scott Claessens (University of Auckland)
Best Poster Award: Ryoko Takikawa & Yasuyuki Fufukawa (Waseda University)

Announcing HBES 2023 Palm Springs

Mark your calendars: HBES 2023 is planned to be in-person in Palm Springs, California, from May 31 – June 3. Hope to see you there!
Bookmark the HBES conference website



The evolutionary origins of fair fights

by Aaron Sell

In early July 2004, the lead singer of Misfits – Glenn Anzalone (better known as Danzig) got into an argument with a fellow musician Danny Marianino backstage after a concert. After some aggressive words, Danzig pushed Danny back. It is important to know that Danzig was widely known for his aggressive and formidable nature, his deep baritone singing voice, and his muscular build. His body type was so befitting of a muscular hero that he was approached to audition for the role of Wolverine in the original X-men movie.  He was also a practitioner of Jeet Kune Do, the martial arts style of Bruce Lee, and a student of Muay Thai. And so, one can imagine his fans reaction when, following Danzig’s push, Danny promptly knocked the singer unconscious with a rapid right hook to the face. Not yet knowing he was unconscious, his fans yelled for him to kick Danny’s ass, but upon realizing he was no longer sentient, a Danzig fan yelled out, “Cheap shot.”  The video has been immortalized online.

Like most human concepts, the “cheap shot” or “unfair fight” or “sucker punch” are immediately intuitive, but contain a computational complexity to them that requires careful scientific study to map. What exactly is a cheap shot? How can a fight, which involves two people (usually men) beating each other until one is incapacitated or gives up, be in any way “fair”? “Fair” usually means evenly or equitably divided, but a fight is a fight precisely to determine a winner and a loser – one gets victory, the other shame and injury. “Fair” means something else here.

Let us start with first principles. Fights are dangerous, but contain useful information about who is a better fighter. This information was of crucial value to our ancestors; so much so that we appear to have evolved numerous complex perceptual mechanisms for assessing the fighting ability of men (Sell et al. 2009; Sell 2012). However, some aspects of fighting ability cannot be perceived by the visual system; for example, reaction time, hand-eye coordination, pain thresholds, etc. Only a bout of aggression reveals these in their sum and interactions, and so the outcomes of such fights serve as a particularly accurate signal of fighting ability.

However, fighting is inherently costly and dangerous. And so natural selection has designed, in many animals including humans, ritualized bouts of aggression wherein the organisms fight using restrained attacks meant to demonstrate fighting ability while diminishing the chance for lethal or injurious aggression. Cichlid fish, for example, will “tail beat” at each other generating waves that crash into their opponents and reveal their bodily strength. Only if those early less lethal means of aggression fail to reveal a victor do they escalate to actual biting. Similar patterns can be seen among housecats who will “punch” each other with claws withdrawn before using fangs. Danzig demonstrated the typical human pattern of pushing and shoving at the start of a typical fight.

The accuracy of these bouts, however, can be compromised by temporary circumstances that make a weaker fighter more likely to win, e.g. they attacked a sleeping opponent. In such a circumstance, the outcome of the fight is no longer a valid cue of fighting ability. Therefore, the outcome of such a fight can be dismissed (at least in part) as a cue of fighting ability. On this theory, a “fair” fight is one that is free of temporary asymmetries in a fighting ability.

In a study run on a sample of 300 US citizens, Daniel Sznycer, Matt Meyers, and I, showed that fights are deemed “unfair” when they contain such asymmetries. For example, in one case a teenager had injured his arm in gym class before a fight. In the control case, the teenager’s injury had recovered. Those subjects that read about the injured arm, found the subsequent fight unfair. In other cases, subjects read about a fight where the putative winner had help from a friend (unfair), was unprepared for aggression (i.e. “sucker punch”, unfair), or used a weapon when their opponent had declined to use it (unfair). In my favorite case, subjects read about an escalating fight with rocks and a tire iron. The two conditions contained exactly the same words, but in the “rapid escalationcondition the winner used the tire iron early in the fight, and in the “slow escalation” condition he used it later in the fight. When the winner used the tire iron early it was deemed unfair. When used late, after the opponent had a rock…it was fair. This is likely what Danzig’s fan was referring to when she called the punch a “cheap shot”; Danzig was in the pushing and shoving portion of the fight, while Danny rapidly escalated to a punch.

The evolutionary function of analyzing fairness in a fight was demonstrated when we asked subjects who would win a rematch if the fighters fought again (after they had recovered). In all but one of the five cases, there was a penalty assigned to a fighter who won unfairly. If they had won unfairly in their initial fight, subjects predicted they would be less likely to win a rematch. In short, “cheating” to win makes you seem weaker. And thus, Danzig’s fan was asking us to discount the fight and refrain from concluding that the Misfit’s singer was weaker than Danny.

Additional implicit fighting rules are contained in a concept of “honor”, and serve to minimize the costs to the combatants. For example, continuing to hit an opponent that has already surrendered was not deemed “unfair” but was considered immoral and dishonorable. Similarly, challenging and defeating someone who was clearly weaker (e.g. an elderly professor) was seen as dishonorable, even though the fight did show in a valid way who was a better fighter.

In short, humans appear to have evolved concepts (similar to those at work in other animals) that contain rules for combat meant to preserve the accuracy of assessing fighting ability while minimizing costs to the combatants. These rules include the absence of temporary asymmetries that bias the fight and tactical restraint that limits the kinds of attacks that are permissible unless it is part of mutual simultaneous escalation, e.g. eye-gouging, knees to the groin, weaponry, etc.

The computational analysis of fairness and honor in fights is just beginning, but the functional design of the concepts and their widespread existence in the animal kingdom demonstrate that only an evolutionary psychological perspective will be able to explain it.

classical statue of wrestling

Does facial shape predict real-world fighting ability in men?

by Neil Caton, Samuel Pearson, & Barnaby Dixon

The presence of dedicated pre-registered replication submissions in peer-reviewed journals is important for maintaining and improving the self-correcting tendency of the scientific enterprise. Replications inform us when we have (un)knowingly been led astray, and given the alarmingly high rates of false positives found in psychology to date, it is clear that we need more replications if the field is to continue separating the wheat from the chaff.

We recently conducted a pre-registered replication of a popular and influential study by Třebický et al. (2013) that was published in Psychological Science. This was the first study to provide scientific evidence for the claim that the same facial features are associated with both real-world fighting success and dominance judgments. Třebický and colleagues were the first to use Ultimate Fighting Championships data in the psychological sciences – a novel, creative, and unique idea. They correlated the entire facial morphology of UFC fighters’ with their fighting success and perceived aggressiveness. Men’s facial features predicted their actual fighting success, and participants could unconsciously perceive their fighting success simply by looking at their face. In our eyes, this is an important finding using a creative methodology that provides the first evidence in support of the claim that the face may be shaped by intrasexual selection—a long-standing debate in evolutionary face research.

Our acclaim for Třebický et al. (2013) led us to read the paper multiple times. Over those readings, several of study’s methodological details struck us as a cause for concern, and hence, formed the rationale for our decision to pursue a replication. Firstly, the association between facial shape and fighting success was found only in the combined sample of 19 light heavyweight and 14 heavyweight fighters. Second, Třebický and colleagues excluded certain groups of participants (e.g., men with moustaches and beards, Africans and Asians) prior to analysis, and the results were slightly under the significance threshold. There was no explanation for these exclusions in the original paper, likely owing to the tight word restrictions of Psychological Science at the time. Finally, Třebický and colleagues examined which facial structures were associated with actual fighting success and perceived aggressiveness, but not those associated with perceived fighting ability. While Třebický and colleagues examined the facial traits associated with fighting success, this doesn’t necessarily mean that participants perceived these traits as cues to fighting success (particularly when considering that Třebický and colleagues found that perceived ability did not significantly predict actual fighting ability). Overall, we acknowledge that Třebický et al. (2013) was the first study on the topic, and therefore there was no standardised process at the time for this creative and novel methodology.

To form the dataset for our replication project, we collected fight statistics, body composition and morphology, demographic information, and photos of 516 male fighters in the Ultimate Fighting Championship. We attached 36,636 facial landmarks to these 516 faces. We then collected data from 1,000 United States-based online raters to judge these 516 faces on perceived aggressiveness and fighting ability.

Consistent with the original study, we found that men with masculine facial features (e.g., large nose, deep-set eyes) were seen as more aggressive, independent of their body size. We also found novel evidence that men with masculine facial features were seen as better fighters, which was because these men were seen as being bigger overall. These analyses between facial shape and perceived fighting ability were not performed in the original study, but was our novel extension of the original study. We did not find an association between facial structure and fighting success. There could be several reasons for this non-significant association: the UFC contains the best fighters in the world, mixed-martial-arts competitions are often legally and ethically required to have weight categories, and/or win percentage may not be an ideal reflection of pure fighting success. If men with masculine facial features are seen as better fighters because they’re bigger overall, then men’s masculine facial features could predict their fighting success in the few championships that don’t have weight restrictions—not because the face predicts fighting success in itself, but because men with bigger faces are bigger overall.

Strikingly, we often found negative relations between perceived aggressiveness and fighting ability on overall win percentage (i.e., more successful fighters were perceived as less successful and aggressive). Třebický et al. (2013) noted some excellent points in their discussion section that we consider to be of importance here, one of which was postulating that human psychological systems track force output. To echo their suggestions, it could be that human psychological systems positively track knockout power but negatively track the other avenues to victory, such as submission and decision victories, leading to an overall negative association.

Overall, our results support the original Třebický et al. (2013) study in some ways but not in others. Humans may have evolved psychological mechanisms to aid in assessments of aggressiveness or competitive tendency, however they do not support the argument that structural facial cues are honest indicators of competitive ability.

Read the paper: Is facial structure and honest cue to real-world dominance and fighting ability in men? A pre-registered direct replication of Třebický et al. (2013)

When and Why We Choose Strong Men as Allies

by Mitch Brown, Donald Sacco, Nicole Barbaro, and Kelsey M. Drea

In early 2021, the common professional wrestling trope of the “stable,” a group of wrestlers with a common goal of dominance within a wrestling promotion, returned to All Elite Wrestling (AEW) with William Regal allying with Bryan Danielson and Jon Moxley. These scripted alliances have a seemingly universal understanding of how men forge bonds with each other based on perceptions of how they may aide in physical conflict. It could even be possible that these stories reflect how men have forged these alliances throughout evolutionary history. Such decisions are likely shaped by carefully navigating when (and whether) strong allies are desirable in attaining group goals.

Humans have been engaged throughout history in forming groups that facilitate goals. The process of choosing allies may have some ancestral roots. These preferences could help people identify those best suited to ensure their safety and access to resources from competitors, particularly when there could have been limited access to resources or threats of violence from other groups. People could have historically identified formidable allies to address these potential threats. Who were the best allies? Recognizing the best allies could happen through physical features that could demonstrate men’s physical prowess, given considerable research demonstrating such cues may connote actual strength. For example, men’s facial width-to-height ratio (fWHR), a configuration of facial width relative to its height, is associated with perceptions of aggression and related to their actual fighting ability.

Although perceptions of dominant personalities through fWHR are less universal than previously thought, men with a higher fWHR remain consistently perceived as more formidable and intimidating to perceivers. In fact, these perceptions offer a kernel of truth. Male professional fighters with higher fWHRs are more successful in certain aspects of combat (e.g., grappling), with archaeological records suggesting that formidable men were more likely to survive violent conflicts. These men also find themselves more prone to using aggressive interpersonal tactics.

With these (often true) stereotypes people make about men based on their fWHR, it would seem likely that people might choose high-fWHR men for physically demanding group tasks as allies – which is indeed the case for physically strenuous sports like American football. In a recent study, my collaborators and I sought to replicate these findings using a pair of tasks that could reflect, in part, realistic features of ancestral coalitional alliance, namely tug-of-war and escape rooms. In three studies, we presented participants with men’s faces that varied in fWHR, with half having high fWHRs and others low fWHRs. Our results conceptually replicated previous effects by showing that people chose men with high fWHRs more frequently for tug-of-war and were perceived as physically strong and effective in using their strength to get the job done.

Now that we knew men were chosen for strength tasks based in part on their fWHR, our next step was to know whether these preferences for high-fWHR men extend to choosing allies for protection tasks specifically. We got participants into similar competitive or cooperative mindset using a priming procedure. Then, participants chose from the same options of men’s faces as the previous studies under the assumption that they would accompany them to a football game against an historic rival of their university (in our case, Southern Miss versus Mississippi State). Knowing how football rivalries play out in the Southern U.S., that environment could get tense! When in a competitive mindset, individuals preferred men with high fWHRs over those with low fWHRs, aligning with our predictions that formidable men would be desirable for potential outgroup protection. Preferences weren’t influenced by cooperative mindset.

Nonetheless, the formidable ally could often betray his teammates for his own benefit. This potential for exploitation from the ally seems to mirror additional research suggesting a wariness to formidable men based on the possibility of the costs they could inflict. We tested this idea in a final study within this paper to determine if a competitive mindset makes the perceived threat of high-fWHR men less apparent. Using the same competitive versus cooperative mindset priming procedures described above, participants did a visual bias task that measures participants’ motivation to approach or avoid a high and low-fWHR men. Although the competitive or cooperative mindsets had no effect, people did view high-fWHR men as more threatening than low-fWHR men across under both conditions. This means that the recruitment of formidable men may reflect an “uneasy alliance” with a perceiver who may be wary of this potential betrayal.

Overall, these findings provide continued support for how historically derived perceptions of men and their physical abilities shape how people engage them in everyday environments, showing how individuals navigate social landscapes while making best estimates for the utility of their own proverbial stablemates.

Read the paper: Contextual factors that heighten interest in coalitional alliances with men possessing formidable facial structures

Can We Read Someone’s Trustworthiness in Their Face?

by Bastian Jaeger

In his autobiography, Charles Darwin recounts the time he approached the captain of the HMS Beagle. Darwin was keen on joining the crew on an upcoming trip around the world as the expedition’s naturalist, but he needed the captain’s approval. Despite recommendations by friends, the captain was reluctant at first. He thought that Darwin wasn’t cut out for the long journey – because of the shape of his nose. The captain was a strong believer in physiognomy, the idea that a person’s character is revealed in their facial appearance. Luckily, he ultimately decided to give Darwin a chance after all.

Physiognomy has a long history in scholarly thought, dating back to at least ancient Greece. Today, the idea that a person’s nose is indicative of their character may seem laughable. In scientific circles, physiognomy and phrenology (the practice of inferring character traits from skull measurements) are widely regarded as pseudoscience. But decades of research on first impressions also suggest that we are all physiognomists to some degree. We might not measure a person’s nose, but we still tend to form judgments about others based on their facial appearance. Research shows that when we meet a stranger, we immediately form an impression based on their facial appearance. This process seems to occur relatively automatically –  it only takes a few hundred milliseconds to judge whether a person seems trustworthy or not. These split-second judgments can be very consequential because people rely on them when making many important decisions. A person’s facial appearance can influence if they are hired for a job, found guilty in court, or trusted in a social interaction.

Can we actually tell how trustworthy someone is based on their facial appearance? This is what we set out to test. We were not the first to tackle this question, but previous research on the accuracy of trustworthiness impressions has yielded mixed results. Some researchers found that people can discriminate between trustworthy and untrustworthy individuals based on a facial photograph with slightly-higher-than-chance accuracy. Other studies yielded no evidence for accuracy. The plausibility of accurate trustworthiness detection has also been questioned (why wouldn’t people evolve to look trustworthy but then exploit the trust of others by acting selfishly?) and it is unclear which facial features “give away” a person’s trustworthiness.

It seems like more evidence is needed to address this question, so in a recent article, we set out to test the accuracy of trustworthiness impressions while also addressing some limitations of previous work. Misplaced trust can be consequential in everyday life. In our studies, we therefore let participants make decisions with tangible outcomes. Similar to previous studies, we let participants play a trust game. We gave some money to a sample of trustors, 131 students from the University of Zurich, who decided whether to keep the money or send it to a trustee. If the money was sent, it was tripled and the trustee had to decide if they want to split the tripled amount with the trustor (reciprocating their partner’s trust) or keep all of the money for themselves (betraying their partner’s trust). Trustors interacted with 31 different trustees, also students at the University of Zurich, and they saw a photo of the trustee’s face on each trial.

Replicating previous work, we found that trustors relied on the facial appearance of their interaction partners when deciding whom to trust. Trustees who were rated as more trustworthy-looking based on their photo were more likely to receive money from their partners. However, trustors were not able to invest their money in a smart way – they were not more likely to send money to trustees who were actually more trustworthy (those who indicated that they would return more of the money if trusted). We found similar results when analyzing how much money trustors earned across all interactions. If seeing the face of an interaction partner gives trustors a strategic advantage (because they can infer their partner’s trustworthiness to some degree) then they should be able to earn more money than a person who trusts at random. This was not the case. In fact, trustors would have earned more money by following another very simple strategy – always keeping their endowment and never trusting anyone (participants in our study turned out to be not very trustworthy).

Maybe participants didn’t send money to the trustees because they believed that they would get more in return, but because it felt wrong to signal to a stranger that they can’t be trusted? We tested this alternative explanation in another study where we simply asked participants to predict how trustworthy the photographed individuals are. We paid them when they made more accurate predictions, but again, trustworthiness judgments were not accurate. We also tested the robustness of our findings in a few other ways. Instead of showing participants cropped photos that only revealed internal facial features, we showed them the original photos that also revealed trustees’ facial structure and hairstyle. We tested detection accuracy for male and female trustees separately. We explored if trustors who are more confident in their decisions are more accurate. In all cases, we found that our participants were unable to detect the trustworthiness of their interaction partners.

Our studies suggest that modern science was right to brand physiognomy as a pseudoscience. It doesn’t seem like we can judge a person’s character just by looking at their face. First impressions may come to mind quickly, but our findings suggest that we better second-guess them. So before you trust or distrust a stranger because it feels like it’s the right decision, ask yourself what your evaluation is based on. If they simply “look trustworthy” to you, maybe find some better information first before making a decision.

Read the paper: Can people detect the trustworthiness of strangers based on their facial appearance?