Joshua Tybur

• Ph.D. Psychology
• Professor (Assistant) at Vrije Universiteit Amsterdam

Multiple proposals suggest that xenophobia increases when infectious disease threats are salient. The current longitudinal study tested this hypothesis by examining whether and how anti-immigrant sentiments varied in the Netherlands across four time points during the COVID-19 pandemic (May 2020, February 2021, October 2021 and June 2022 through Fly...

Motivations to avoid infectious disease seem to influence prejudice toward some groups, including groups not explicitly associated with infectious disease. The standard explanation relies on signal detection theory and proposes that pathogen detection should be biased toward making many false alarms (false positives) and few misses (false negatives...

Nonverbal vocalisations like laughter, sighs, and groans are a fundamental part of everyday communication. Yet surprisingly little is known about the social norms concerning which vocalisations are considered appropriate to express in which context (i.e., display rules). Here, in two pre-registered studies, we investigate how people evaluate the ap...

Most Five-Factor Model (FFM) questionnaire items contain unique variance that is partly heritable, stable, and consensually observable, demonstrates consistent associations with age and sex, and predicts life outcomes beyond higher order factors. Extending these findings to the HEXACO model, we meta-analyzed single-item cross-rater agreement, herit...

Nonverbal vocalisations like laughter, sighs, and groans are a fundamental part of everyday communication. Yet surprisingly little is known about the social norms concerning which vocalisations are considered appropriate to express in which context (i.e., display rules). Here, in two pre-registered studies, we investigate how people evaluate the ap...

Fundamental frequency ( f o ) is the most perceptually salient vocal acoustic parameter, yet little is known about how its perceptual influence varies across societies. We examined how f o affects key social perceptions and how socioecological variables modulate these effects in 2,647 adult listeners sampled from 44 locations across 22 nations. Low...

Fitouchi et al. persuasively argue against popular disgust-based accounts of puritanical morality. However, they do not consider alternative account of moral condemnation that is also based on the psychology of disgust. We argue that these other disgust-based accounts are more promising than those dismissed in the target article.

Third party punishment (TPP) is thought to be crucial to the evolution and maintenance of human cooperation. However, this type of punishment is often not rewarded, perhaps because punishers' underlying motives are unclear. We propose that the expression of moral emotions could solve this problem by advertising such motives. In each of three experi...

The modern world affords unprecedented opportunities for individuals to express moral sentiments. The widespread distribution of one specific type of sentiment — outrage — has consequences for social and political harmony. The current investigation contributes to better understanding these consequences by examining what types of aggression people e...

The modern world affords unprecedented opportunities for individuals to express moral sentiments. The widespread distribution of one specific type of sentiment – outrage – has consequences for social and political harmony. The current investigation contributes to better understanding these consequences by examining what types of aggression people e...

Why do some people find allure in artworks that focus on elements of repulsion, horror, and the bizarre? Across two studies, we examined how openness to experience, sensation seeking, need for affect, emotionality, disgust sensitivity, political orientation, art knowledge, and participant gender relate to the liking of grotesque art. In Study 1, pa...

People vary both in their embrace of their society’s traditions, and in their perception of hazards as salient and necessitating a response. Over evolutionary time, traditions have offered avenues for addressing hazards, plausibly resulting in linkages between orientations toward tradition and orientations toward danger. Emerging research documents...

How well can social scientists predict societal change, and what processes underlie their predictions? To answer these questions, we ran two forecasting tournaments testing the accuracy of predictions of societal change in domains commonly studied in the social sciences: ideological preferences, political polarization, life satisfaction, sentiment...

Fitouchi and colleagues persuasively argue against popular disgust-based accounts of puritanical morality. However, they do not consider alternative disgust-based accounts of moral condemnation. We argue that these other accounts are more promising than those dismissed in the target article.

Intergroup biases are widespread across cultures and time. The current study tests an existing hypothesis that has been proposed to explain such biases: the mind has evolved to interpret outgroup membership as a cue to pathogen threat. In this registered report, we test a core feature of this hypothesis. Adapting methods from earlier work, we exami...

Intergroup biases are widespread across cultures and time. The current study tests an existing hypothesis that has been proposed to explain such biases: the mind has evolved to interpret outgroup membership as a cue to pathogen threat. In this registered report, we test a core feature of this hypothesis. Adapting methods from earlier work, we exami...

Genetic factors have a substantial influence on individuals' food preferences, but less is known about their influence on abstinence from eating meat and fish. Here we looked at the influence genetics may have on pescetarianism (not eating meat but eating fish) and vegetarianism (not eating meat and fish) in a Dutch twin sample (N = 8,196). We also...

People vary in the extent to which they embrace their society’s traditions, impacting a range of social and political phenomena. People also vary in the degree to which they perceive disparate dangers as salient and necessitating a response. Over evolutionary time, traditions likely regularly offered direct and indirect avenues for addressing hazar...

Most Five-Factor Model questionnaire items contain unique variance that 1) is heritable, stable, and observable; 2) demonstrates consistent associations with age and sex, and 3) is predictive of life outcomes over and above higher-order factors. This is consistent with items indexing a unique level of the personality trait hierarchy—nuances. Extend...

Hundreds of studies have assessed variation in the degree to which people experience disgust toward substances associated with pathogens, but little is known about the mechanistic sources of this variation. The current manuscript uses olfactory perception and threshold methods to test whether it is apparent at the cue-detection level, at the cue-in...

Hundreds of studies have assessed variation in the degree to which people experience disgust toward substances associated with pathogens, but little is known about the mechanistic sources of this variation. The current investigation uses olfactory perception and threshold methods to test whether it is apparent at the cue-detection level, at the cue...

Previous work has reported a relation between pathogen-avoidance motivations and prejudice toward various social groups, including gay men and lesbian women. It is currently unknown whether this association is present across cultures, or specific to North America. Analyses of survey data from adult heterosexuals ( N = 11,200) from 31 countries show...

Over the past decade, a small literature has tested how trait-level pathogen avoidance motives (e.g., disgust sensitivity) and exposure to pathogen cues relate to preferences for facial symmetry and sexual dimorphism. Results have largely been interpreted as suggesting that the behavioral immune system influences preferences for these features in p...

Over the past decade, a small literature has tested how trait-level pathogen-avoidance motives (e.g., disgust sensitivity) and exposure to pathogen cues relate to preferences for facial symmetry and sexual dimorphism. Results have largely been interpreted as suggesting that the behavioral immune system influences preferences for these features in p...

Over the past decade, evolutionary psychologists have proposed that many moral stances function to promote self-interests. At the same time, behavioral geneticists have demonstrated that many moral stances have genetic bases. We integrated these perspectives by examining how moral condemnation of recreational drug use relates to sexual strategy (i....

In Western nations, the simultaneous increase in interracial relationships and the use of dating apps such as Tinder has raised questions regarding the influence of dating apps on partner choice. This study examines whether principles of assortative mating – people's tendency to select partners similar to them – apply to dating apps, or whether the...

People vary in the degree to which they enjoy eating meats versus plants. This paper examines the genetic and environmental roots of this variation, as well as the genetic and environmental roots of meat neophobia, plant neophobia, and vegetarianism/veganism. Using data from 9,319 adult Finnish twins and siblings of twins (551 MZ, 861 DZ complete;...

People vary in the degree to which they enjoy eating meats versus plants. This paper examines the genetic and environmental roots of this variation, as well as the genetic and environmental roots of meat neophobia, plant neophobia, and vegetarianism/veganism. Using data from 9,319 adult Finnish twins and siblings of twins (551 MZ, 861 DZ complete;...

Research on romantic jealousy has traditionally focused on sex differences. We investigated why individuals vary in romantic jealousy, even within the sexes, using a genetically informed design of ~7700 Finnish twins and their siblings. First, we estimated genetic, shared environmental and nonshared environmental influences on jealousy, Second, we...

Although multiple leading papers in the behavioral immune system literature have proposed that food deprivation affects responses to pathogen cues, evidence supporting this proposition is scarce. Here, we report results from what we believe to be the most comprehensive test of the effects of hunger on responses to pathogen cues to date. Participant...

A broad literature indicates that pathogen, sexual, and moral disgust sensitivity relate to, among other things, political attitudes, moral condemnation, and symptoms of psychopathology. Consequently, disgust sensitivity has been widely assessed across subfields of psychology. Yet, no work has examined whether self-reports in disgust sensitivity re...

Existing work indicates that socio-political attitudes (or: ideology) are associated with personality, with Social Dominance Orientation and Right-Wing Authoritarianism relating most strongly to honesty-humility and openness to experience, the two value-related domains of the HEXACO framework. Using a sample of 7067 twins and siblings of twins (inc...

Anger and moral disgust, as the two most important moral emotions, have been studied for decades. However, a limited number of methods were used to measure these emotions, mostly by using similarity evaluation of facial expressions. In the current study, we introduced non-verbal vocalization of these emotions into the application of emotion endorse...

People are quick to form impressions of others’ social class, and likely adjust their behavior accordingly. If social class is linked to prosociality, as literature suggests, then an interaction partner’s class should affect prosocial behavior, especially when costs or investments are low. We test this expectation using social mindfulness (SoMi) an...

People vary in their willingness to try new foods. This variation, which is most frequently measured using the Food Neophobia Scale (FNS; Pliner & Hobden, 1992), has been interpreted as unidimensional. In four studies (N’s = 210, 306, 160, and 161), we 1) demonstrate that food neophobia varies across meat and plant dimensions, 2) explore the validi...

To understand the consequences of cleansing, Lee and Schwarz favor a grounded procedures perspective over recently developed disgust theory. We believe that this position stems from three errors: (1) interpreting cleansing effects as broader than they are; (2) not detailing the proximate mechanisms underlying disgust; and (3) not detailing adaptive...

Conspicuous conservation refers to pro-environmental activities that are intended as signals of some attractive quality of the actor. As some of these qualities are desirable in romantic partners, people may purchase green products or services to impress potential romantic partners. We propose that conspicuous conservation communicates generosity –...

Over the past decade, evolutionary psychologists have proposed that many moral stances function to promote self-interests, and behavioral geneticists have demonstrated that many moral stances have genetic bases. We integrate these perspectives by examining how moral condemnation of recreational drug use relates to sexual strategy (i.e., being more...

People vary in their willingness to try new foods. This variation, which is most frequently measured using the Food Neophobia Scale (FNS; Pliner & Hobden, 1992), has been interpreted as unidimensional. In four studies (N’s = 210, 306, 160, and 161), we 1) demonstrate that food neophobia varies across meat and plant dimensions, 2) explore the validi...

Perceived intent is a pivotal factor in moral judgement: intentional moral violations are considered more morally wrong than accidental ones. However, a body of recent research argues that intent is less important for moral judgements of impure acts – that it, those acts that are condemned because they elicit disgust. But the literature supporting...

A substantial body of research has illuminated psychological adaptations motivating pathogen avoidance, mechanisms collectively known as the behavioral immune system. Can knowledge about these mechanisms inform how people respond to widespread disease outbreaks, such as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) [coronavirus d...

The tendency to attend to and avoid cues to pathogens varies across individuals and contexts. Researchers have proposed that this variation is partially driven by immunological vulnerability to infection, though support for this hypothesis is equivocal. One key piece of evidence (Miller & Maner, 2011) shows that participants who have recently been...

Decades of research have shown that about half of individual differences in personality traits is heritable. Recent studies have reported that heritability is not fixed, but instead decreases across the life span. However, findings are inconsistent and it is yet unclear whether these trends are because of a waning importance of heritable tendencies...

Behavioral-immune-system research has illuminated how people detect and avoid signs of infectious disease. But how do we regulate exposure to pathogens that produce no symptoms in their hosts? This research tested the proposition that estimates of interpersonal value are used for this task. The results of three studies (N = 1,694), each conducted u...

Dozens of studies have indicated that individuals more prone to experiencing disgust have stronger symptoms of anxiety disorders—especially contamination sensitivity. However, no work has informed the degree to which this relationship arises from genetic factors versus environmental factors. In the present study, we fill this gap by measuring disgu...

Behavioral immune system research has illuminated how people detect and avoid signs of infectious disease. But how do we regulate exposure to pathogens that produce no symptoms in their hosts? This manuscript tests the proposition that estimates of interpersonal value are used for this task. Three studies (N = 1694), each conducted using U.S. sampl...

The tendency to attend to and avoid cues to pathogens varies across individuals and contexts. Researchers have proposed that this variation is partially driven by immunological vulnerability to infection, though support for this hypothesis is equivocal. One key piece of evidence finds that recently ill participants – who may have a reduced ability...

People often report disgust toward moral violations. Some perspectives posit that this disgust is indistinct from anger. Here, we replicate and extend recent work suggesting that disgust and anger toward moral violations are in fact distinct in terms of the situations in which they are activated and their correspondence with aggressive sentiments....

Across societies, humans punish norm violations. To date, research on the antecedents and consequences of punishment has largely relied upon agent-based modeling and laboratory experiments. Here, we report a longitudinal study documenting punishment responses to norm violations in daily life (k = 1507; N = 257) and test pre-registered hypotheses ab...

Androgenic Alopecia affects the majority of aging men and consequently a substantial number of leaders. Yet, there is little research on how male pattern baldness (MPB) influences leader perceptions, and no research on context-specific leader preferences for bald men. Across three studies, we add to this sparse literature by investigating a) how ba...

Multiple studies report that disgust-eliciting stimuli are perceived as salient and subsequently capture selective attention. In the current study, we aimed to better understand the nature of temporal attentional biases toward disgust-eliciting stimuli and to investigate the extent to which these biases are sensitive to contextual and trait-level p...

Multiple studies report that disgust-eliciting stimuli are perceived as salient and subsequently capture selective attention. In the current study, we aimed to better understand the nature of temporal attentional biases toward disgust-eliciting stimuli and to investigate the extent to which these biases are sensitive to contextual and trait-level p...

Are male and female immigrants viewed similarly or differently? Consistent with an evolutionary threat management perspective, we suggest that the answer to this question depends upon what types of threats immigrant groups are perceived as posing. In the present study, we compared attitudes toward male and female immigrants from either a violent ec...

This chapter covers the 20+ year history of disgust sensitivity research by summarizing and contrasting different disgust sensitivity instruments and discussing how these instruments are used and interpreted.

A broad literature indicates that pathogen, sexual, and moral disgust sensitivity relate to, among other things, political attitudes, moral condemnation, and symptoms of psychopathology. As such, instruments measuring disgust sensitivity have been widely used across subfields of psychology. Yet, surprisingly little work has examined whether self-re...

Past research suggests that pathogen-avoidance motives (e.g., disgust sensitivity) relate to greater opposition to immigration. Two accounts have been proposed to explain this relationship, one of which emphasizes proximally avoiding outgroups, and the other of which emphasizes adherence to traditional norms. According to the former, immigrants are...

Past research indicates that patient perceptions of surgeon warmth and competence influence treatment expectancies and satisfaction with treatment outcomes. Stereotypes have a powerful impact on impression formation. The present research explores stereotypes about surgeon warmth and competence and investigates the extent to which surgeon gender inf...

Supplementary material data file. (XLSX)

Prosociality is a central topic in positive psychology. An important but under-studied distinction can be made between active and reactive expressions. We suggest that the novel construct of social mindfulness represents active rather than reactive prosociality. Across four studies (N = 2,594), including a multi-wave representative sample spanning...

Researchers have proposed that intergroup prejudice is partially caused by behavioral immune system mechanisms. Across four studies (total N = 1,849), we used both experimental (pathogen priming) and individual differences (pathogen disgust sensitivity [PDS]) approaches to test whether the behavioral immune system influences prejudice toward immigr...

People often report disgust toward moral violations. Some perspectives posit that this disgust is indistinct from anger. Here, we test an alternative perspective: that disgust corresponds with condemnation strategies that are less costly – but also less effective at deterrence – than those corresponding with anger. We tested three hypotheses concer...

Excessive meat consumption is associated with a range of environmental problems. In this investigation, we examined the effectiveness of three types of persuasive messages posited to affect attitudes toward meat consumption. The first two messages contained health and environment-related appeals (e.g., the moral consequences of environmental degrad...

Why is disgust sensitivity associated with socially conservative political views? Is it because socially conservative ideologies mitigate the risks of infectious disease, whether by promoting out-group avoidance or by reinforcing norms that sustain antipathogenic practices? Or might it be because socially conservative ideologies promote moral stand...

People vary in the degree to which they experience disgust toward—and, consequently, avoid—cues to pathogens. Prodigious work has measured this variation and observed that it relates to, among other things, personality, psychopathological tendencies, and moral and political sentiments. Less work has sought to generate hypotheses aimed at explaining...

Raised progesterone during the menstrual cycle is associated with suppressed physiological immune responses, reducing the probability that the immune system will compromise the blastocyst's development. The Compensatory Prophylaxis Hypothesis proposes that this progesterone-linked immunosuppression triggers increased disgust responses to pathogen c...

Raised progesterone during the menstrual cycle is associated with suppressed physiological immune responses, reducing the probability that the immune system will compromise the blastocyst’s development. The Compensatory Prophylaxis Hypothesis proposes that this progesterone-linked immunosuppression triggers increased disgust responses to pathogen c...

Raised progesterone during the menstrual cycle is associated with suppressed physiological immune responses, reducing the probability that the immune system will compromise the blastocyst's development. The Compensatory Prophylaxis Hypothesis proposes that this progesterone-linked immunosuppression triggers increased disgust responses to pathogen c...

Infectious disease is an ever-present threat in daily life. Recent literature indicates that people manage this threat with a suite of antipathogenic psychological and behavioral defense mechanisms, which motivate the avoidance of people and objects bearing cues to pathogen risk. Here, we demonstrate that self-image is also impacted by these mechan...

The behavioral immune system includes motivational systems for avoiding contact with pathogens, including those transmitted by other people. Motivations to avoid others may depend not only on the perceived risk of infection but also on perceived benefits of social interaction. Based on this idea, we hypothesise that more agreeable people may experi...

Maestripieri et al. pit evolutionary psychology against social psychological and economic perspectives in a winner-take-all empirical battle. In doing so, they risk positioning evolutionary psychology as an antagonistic subdisciplinary enterprise. We worry that such a framing may exacerbate tensions between “competing” scientific perspectives and l...

In response to the same moral violation, some people report experiencing anger, and others report feeling disgust. Do differences in emotional responses to moral violations reflect idiosyncratic differences in the communication of outrage, or do they reflect differences in motivational states? Whereas equivalence accounts suggest that anger and dis...

Across five studies using samples from both Japan and United States (N = 2345), we take a multi-method approach to test the prediction from life history theory that a slow, compared to fast, life history strategy promotes investment in cooperative relationships. Studies 1 and 2 examined how different measures as proxies for life history strategy (i...

Previous work has found that configuring participants into high-power versus low-power physical postures caused increases in subjective feelings of power, testosterone, and risk-taking as well as decreases in cortisol. We attempted to replicate and extend this pattern of findings by testing for the mediating role of testosterone and overconfidence...

People who are more avoidant of pathogens are more politically conservative, as are nations with greater parasite stress. In the current research, we test two prominent hypotheses that have been proposed as explanations for these relationships. The first, which is an intragroup account, holds that these relationships between pathogens and politics...

Social interactions are characterized by distinct forms of interdependence, each of which has unique effects on how behavior unfolds within the interaction. Despite this, little is known about the psychological mechanisms that allow people to detect and respond to the nature of interdependence in any given interaction. We propose that interdependen...

Theories suggest that political ideology relates to cooperation, with conservatives being more likely to pursue selfish outcomes, and liberals more likely to pursue egalitarian outcomes. In study 1, we examine how political ideology and political party affiliation (Republican vs. Democrat) predict cooperation with a partner who self-identifies as R...

Moral judgments seem related to the emotion disgust. Evolutionary considerations might illuminate the psychological processes underlying this relation. Several studies have noted that individuals who are more disgust sensitive condemn moral violations more strongly. However, this association could result from both disgust sensitivity and moral judg...

Social class predicts numerous important life outcomes and social orientations. To date, literature has mainly examined how an individual's own class shapes interactions with others. But how prosocially do people treat others they perceive as coming from lower, middle, or higher social classes? Here, in addition to testing effects of self social cl...

Nonoffending mothers of sexually abused children often exhibit high levels of posttraumatic stress (PTS) symptoms. Emerging evidence suggests that trait-like individual differences in sensitivity to disgust play a role in the development of PTS symptoms. One such individual difference, disgust sensitivity, has not been examined as far as we are awa...

The demand for organ transplants far exceeds supply. Underlying this shortfall is the fact that some people choose to register as organ donors, whereas many others decide not to. Why do people vary in their attitudes and choices regarding organ donation? We hypothesize that attitudes toward organ donation and decisions to register as a donor are li...

The existence of individual differences in personality can be puzzling from an evolutionary perspective. This paper offers a general framework for addressing this puzzle by combining insights from evolutionary, situational, and personality perspectives. To arrive at this framework, we first discuss three key evolutionary models for explaining perso...

Objective: Recent work suggests that the psychology of pathogen avoidance has wide-reaching effects on how people interact with the world. These processes - part of what has been referred to as the behavioral immune system- are, in a way, our "evolved" health psychology. However, scholars have scarcely investigated how the behavioral immune system...