bluuebunny/crossref_metadata_2025 huggingface dataset:
Testing the Cuckoldry Risk Hypothesis of Partner Sexual Coercion in Community and Forensic Samples
Authors: Camilleri Joseph A. , Quinsey Vernon L.
Published: July 2015

Evolutionary theory has informed the investigation of male sexual coercion but has seldom been applied to the analysis of sexual coercion within established couples. The cuckoldry risk hypothesis, that sexual coercion is a male tactic used to reduce the risk of extrapair paternity, was tested in two studies. In a community sample, indirect cues of infidelity predicted male propensity for sexual coaxing in the relationship, and direct cues predicted propensity for sexual coercion. In the forensic sample, we found that most partner rapists experienced cuckoldry risk prior to committing their offence and experienced more types of cuckoldry risk events than non-sexual partner assaulters. These findings suggest that cuckoldry risk influences male sexual coercion in established sexual relationships.
Sex Differences in Perceptions of Infidelity: Men Often Assume the Worst
Authors: Goetz Aaron T. , Causey Kayla
Published: July 2015

Given that the costs of underperceiving (i.e., failing to detect) a partner's sexual infidelity would have been greater for men than for women, we hypothesized that men may possess evolved psychological mechanisms designed to overperceive the likelihood of their partner's sexual infidelity. We found support for this hypothesis using two different response formats, a Likert-type scale (Study 1) and a visual analog scale (Study 2). In both studies, men were more likely than women to judge that their partners would commit sexual infidelity in the future. Discussion addresses additional design features of the infidelity detection system.
On the Real Magnitude of Psychological Sex Differences
Authors: Del Giudice Marco
Published: July 2015

A comprehensive evolutionary theory of sex differences will benefit from an accurate assessment of their magnitude across different psychological domains. This article shows that mainstream research has severely underestimated the magnitude of psychological sex differences; the reason lies in the common practice of measuring multidimensional differences one dimension at a time, without integrating them into a proper multivariate effect size (ES). Employing the Mahalanobis distance D (the multivariate generalization of Cohen's d) results in more accurate, and predictably larger, estimates of overall sex differences in multidimensional constructs. Two real-world examples are presented: (1) In a published dataset on Big Five personality traits, sex differences on individual scales averaged d = .27, a typical ES conventionally regarded as “small.” However, the overall difference was D = .84 (disattenuated D = .98), implying considerable statistical separation between male and female distributions. (2) In a recent meta-analytic summary of sex differences in aggression, the individual ESs averaged d = .34. However, the overall difference was estimated at D = .75 – .80 (disattenuated D = .89–1.01). In many psychological domains, sex differences may be substantially larger than previously acknowledged.
Male Scarcity is Differentially Related to Male Marital Likelihood across the Life Course
Authors: Kruger Daniel J. , Schlemmer Erin
Published: July 2015

If marriage markets were only subject to the influences of numerical supply and demand, one would expect that the scarcer sex in a population would have a greater proportion married. Previous research has demonstrated that when males are scarce, they are actually less likely to be married, presumably because their market scarcity enhances their short term mating success and decreases incentives for commitment. However, males in modern societies appear to shift from mating effort to parental investment across the life course. Also, women preferentially value indicators of phenotypic quality for short term relationships, and these signals may be increasingly difficult to display with progressive physiological senescence. We predicted that men in low sex ratio populations would use market scarcity to their advantage for mating effort when young, but would shift towards commitment strategies when older. Data from the 50 largest Metropolitan Statistical Areas in the USA confirmed that a female biased sex ratio was associated with a lower proportion of men married between ages 20 and 29, but a higher proportion of men married between ages 35 and 74.
Enhanced Source Memory for Names of Cheaters
Authors: Bell Raoul , Buchner Axel
Published: July 2015

The present experiment shows that source memory for names associated with a history of cheating is better than source memory for names associated with irrelevant or trustworthy behavior, whereas old-new discrimination is not affected by whether a name was associated with cheating. This data pattern closely replicates findings obtained in previous experiments using facial stimuli, thus demonstrating that enhanced source memory for cheaters is not due to a cheater-detection module closely tied to the face processing system, but is rather due to a more general bias towards remembering the source of information associated with cheating.
Accuracy and Oversexualization in Cross-Sex Mind-Reading: An Adaptationist Approach
Authors: Geher Glenn
Published: July 2015

This research focuses on mating-relevant judgments within an evolutionary framework. Using a methodology that employs personal ads as stimuli, the current study tested predictions from Error Management Theory ( Haselton and Buss, 2000 ) suggesting that males will oversexualize females' desires, showing a tendency to think women are more interested in unrestricted sexual encounters than is warranted. This work further tested whether women's judgments represent an oversexualization of males' desires, which may reflect the adaptive bias of commitment skepticism. This work also tested whether overall accuracy in these judgments was sex-differentiated. 481 young male and female heterosexual adults judged which personal ads (written by opposite-sex individuals) were most desirable as short and long-term mates. All participants then engaged in a cross-sex mind-reading task by guessing which ads were most strongly endorsed by opposite-sex individuals. Males were more accurate than females in guessing long-term desires; females were more accurate than males in guessing short-term desires. Male oversexualization of females' desires was not pronounced in these data. However, female oversexualization of males' was quite pronounced for both short and long-term judgments. Discussion addresses how the sexes may be tuned into different strategic mating cues in the domain of cross-sex mind-reading in addition to how oversexualization of opposite-sex judgments may serve discrete adaptive functions across the sexes.
Hot Topics and Popular Papers in Evolutionary Psychology: Analyses of Title Words and Citation Counts in Evolution and Human Behavior, 1979 – 2008
Authors: Webster Gregory D. , Jonason Peter K. , Schember Tatiana Orozco
Published: July 2015

What do evolutionary psychologists study, which are their most highly cited articles, and which variables predict high citation counts? These are important questions for any emerging science. To help answer these questions, we present new empirical research on publication trends in evolutionary psychology's flagship journal, Evolution and Human Behavior (and its predecessor, Ethology and Sociobiology), from its inception in 1979 to 2008. First, analyses of 8,631 title words published in these journals between 1979 and 2008 (808 articles) show an increasing interest in researching sex, sex differences, faces, and attractiveness. For example, during the Ethology and Sociobiology era (1979–1996), the most frequent title words were “evolutionary,” “human,” “behavior,” “reproductive,” “evolution,” “selection,” and “altruism,” whereas during the Evolution and Human Behavior era (1997–2008), they were “sex,” “attractiveness,” “differences,” “sexual,” “human,” “male,” and “facial.” Second, we reveal the 20 most-cited articles in these journals, which show the importance of research teams. Third, citation analyses for these journals between 1979 and 2002 (562 articles) suggest articles that cite more references are in turn cited more themselves ( r = .44, R2 = .19). Lastly, we summarize recent research that suggests evolutionary psychology is not only surviving, but also thriving, as a new interdisciplinary science.
Emotional Tears as Biological Signals
Authors: Hasson Oren
Published: July 2015

Emotional tears have been shown to enhance the interpretation of sadness that is inferred from facial expressions. The current paper puts emotional tears in an evolutionary context. By using biological signaling theory, it first looks at the distinction between cues and signals, both of which provide information to recipients, except that signals have evolved for that purpose. The conclusion is that a signaling function has yet to be shown. Nevertheless, as emotional tears are likely to function as signals, an analysis of certain inevitable effects of tears on the individual hint at more than a single signaling function, depending on the context in which tears are produced. Emotional tears decrease the perception of gaze direction or of changes in pupil size, and may function as attenuators of intentions. Emotional tears are more likely, however, to function as handicaps. By blurring vision, they handicap aggressive or defensive actions, and may function as reliable signals of appeasement, need or attachment.
The Chronic Dependence of Popular Religiosity upon Dysfunctional Psychosociological Conditions
Authors: Paul Gregory
Published: July 2015

Better understanding the nature, origin and popularity of varying levels of popular religion versus secularism, and their impact upon socioeconomic conditions and vice versa, requires a cross national comparison of the competing factors in populations where opinions are freely chosen. Utilizing 25 indicators, the uniquely extensive Successful Societies Scale reveals that population diversity and immigration correlate weakly with 1st world socioeconomic conditions, and high levels of income disparity, popular religiosity as measured by differing levels of belief and activity, and rejection of evolutionary science correlate strongly negatively with improving conditions. The historically unprecedented socioeconomic security that results from low levels of progressive government policies appear to suppress popular religiosity and creationist opinion, conservative religious ideology apparently contributes to societal dysfunction, and religious prosociality and charity are less effective at improving societal conditions than are secular government programs. The antagonistic relationship between better socioeconomic conditions and intense popular faith may prevent the existence of nations that combine the two factors. The nonuniversality of strong religious devotion, and the ease with which large populations abandon serious theism when conditions are sufficiently benign, refute hypotheses that religious belief and practice are the normal, deeply set human mental state, whether they are superficial or natural in nature. Instead popular religion is usually a superficial and flexible psychological mechanism for coping with the high levels of stress and anxiety produced by sufficiently dysfunctional social and especially economic environments. Popular nontheism is a similarly casual response to superior conditions.
On the Origin of Descended Scrotal Testicles: The Activation Hypothesis
Authors: Gallup Gordon G. , Finn Mary M. , Sammis Becky
Published: July 2015

Male gonads contained in an unprotected skin sack located outside the body cavity are a peculiar mammalian anomaly. We advance the hypothesis that descended scrotal testicles in humans and many other mammals evolved to provide a situation specific means of activating sperm. As a result of consistent temperature differences between the male and female reproductive tracts (i.e., scrotal temperatures are typically maintained at 2-3°C below body temperature), we propose that the rise to body temperature that accompanies insemination into the vagina serves as one of several triggers for the activation of sperm. We explore some of the features of mammalian reproduction and behavior that are consistent with this hypothesis, make some testable predictions, and examine the psychological and behavioral adaptations that have evolved to protect otherwise vulnerable scrotal testicles from damage.
Height among Women is Curvilinearly Related to Life History Strategy
Authors: Buunk Abraham P. , Pollet Thomas V. , Klavina Liga , Figueredo Aurelio José , Dijkstra Pieternel
Published: July 2015

It was hypothesized that women of medium height would show a more secure, long-term mating pattern characterized by less jealousy, less intrasexual competition and a “slower” life history strategy. In three samples of female undergraduate students clear support was found for these hypotheses. In Study 1, among 120 participants, height was curvilinearly related to well-established measures of possessive and reactive jealousy, with women of medium height being less jealous than tall as well as short women. In Study 2, among 40 participants, height was curvilinearly related to intrasexual competition, with women of medium height being less competitive towards other women than tall as well as short women. In Study 3, among 299 participants, height was curvilinearly related to the Mini-K, a well-validated measure of “slower” life history strategy, with women of medium height having a slower life history strategy than tall as well as short women. The results suggest that women of medium height tend to follow a different mating strategy than either tall or short women. Various explanations and implications of these results are discussed.
Predictors of How Often and When People Fall in Love
Authors: Galperin Andrew , Haselton Martie
Published: July 2015

A leading theory of romantic love is that it functions to make one feel committed to one's beloved, as well as to signal this commitment to the beloved ( Frank, 1988 ). Because women tend to be skeptical of men's commitment, this view entails that men may have evolved to fall in love first, in order to show their commitment to women. Using a sample of online participants of a broad range of ages, this study tested this sex difference and several related individual difference hypotheses concerning the ease of falling in love. There was mixed evidence for sex differences: only some measures indicated that men are generally more love-prone than are women. We also found that men were more prone to falling in love if they tended to overestimate women's sexual interest and highly valued physical attractiveness in potential partners. Women were more prone to falling in love if they had a stronger sex drive. These results provide modest support for the existence of sex differences in falling in love, as well as initial evidence for links between several individual difference variables and the propensity to fall in love.
Altruistic Behavior and Cooperation: The Role of Intrinsic Expectation When Reputational Information is Incomplete
Authors: Ellers Jacintha , van der Pool Nadia C. E.
Published: July 2015

Altruistic behavior is known to be conditional on the level of altruism of others. However, people often have no information, or incomplete information, about the altruistic reputation of others, for example when the reputation was obtained in a different social or economic context. As a consequence, they have to estimate the other's altruistic intentions. Using an economic game, we showed that without reputational information people have intrinsic expectations about the altruistic behavior of others, which largely explained their own altruistic behavior. This implies that when no information is available, intrinsic expectations can be as powerful a driver of altruistic behavior as actual knowledge about other people's reputation. Two strategies appeared to co-exist in our study population: participants who expected others to be altruistic and acted even more altruistically themselves, while other participants had low expected altruism scores and acted even less altruistically than they expected others to do. We also found evidence that generosity in economic games translates into benefits for other social contexts: a reputation of financial generosity increased the attractiveness of partners in a social cooperative game. This result implies that in situations with incomplete information, the fitness effects of indirect reciprocity are cumulative across different social contexts.
Indirect Peer Aggression in Adolescence and Reproductive Behavior
Authors: White Daniel D. , Gallup Andrew C. , Gallup Gordon G.
Published: July 2015

Evolutionary psychologists have suggested that indirect aggression during adolescence is a strategy to compete with same-sex peer rivals for resources, status, and mating opportunities. We collected survey data on 143 young adults to determine retrospectively, the amount of indirect aggressive behavior they perpetrated and the amount of indirect victimization they experienced in middle school and high school. We also collected information about reproductive opportunities such as age at first sexual intercourse and number of lifetime sex partners to determine whether aggression or victimization could be used to predict measures of reproductive opportunity. We performed a principal components analysis to develop factors from 16 aggression and victimization variables. Results indicate that females who reported indirect aggression toward peers had earlier ages at first sexual intercourse and females who were more victimized in adolescence experienced later ages at first sexual intercourse. We discuss these results in terms of intrasexual competition and evolutionary theory.
Zoonotic and Non-Zoonotic Diseases in Relation to Human Personality and Societal Values: Support for the Parasite-Stress Model
Authors: Thornhill Randy , Fincher Corey L. , Murray Damian R. , Schaller Mark
Published: July 2015

The parasite-stress model of human sociality proposes that humans' ontogenetic experiences with infectious diseases as well as their evolutionary historical interactions with these diseases exert causal influences on human psychology and social behavior. This model has been supported by cross-national relationships between parasite prevalence and human personality traits, and between parasite prevalence and societal values. Importantly, the parasite-stress model emphasizes the causal role of non-zoonotic parasites (which have the capacity for human-to-human transmission), rather than zoonotic parasites (which do not), but previous studies failed to distinguish between these conceptually distinct categories. The present investigation directly tested the differential predictive effects of zoonotic and non-zoonotic (both human-specific and multihost) parasite prevalence on personality traits and societal values. Supporting the parasite-stress model, cross-national differences in personality traits (unrestricted sexuality, extraversion, openness to experiences) and in societal values (individualism, collectivism, gender equality, democratization) are predicted specifically by non-zoonotic parasite prevalence.
Testosterone Fluctuations in Young Men: The Difference between Interacting with like and Not-Like others
Authors: DeSoto M. Catherine , Hitlan Robert T. , Deol Rory-Sean S. , McAdams Derrick
Published: July 2015

The current study investigated young men's testosterone level changes as a result of interacting with other men. Male participants ( n = 84) were led to believe that a group they would be interacting with was either similar to them or not similar. The interaction was then one of two types: the other group members were inclusive, or the others excluded the participant during the group interaction. Participants provided saliva samples before and after the interaction. Results suggest that interacting with highly similar men increases circulating testosterone whereas interacting with highly dissimilar men actually lowers testosterone. The nature of the interaction was less important than similarity. Considering that testosterone surges may relate to attempts to gain status within one's group, the results are interpreted as consistent with viewing hormonal changes as a mechanism to alter current behavioral propensities in ways that are likely to be most adaptive. Exploratory analyses suggest a methodologically interesting suppressor effect of the self-report items in predicting testosterone changes.
Socio-Demographic Factors Intensifying Male Mating Competition Exacerbate Male Mortality Rates
Authors: Kruger Daniel J.
Published: July 2015

Sex differences in mortality rates stem from a complex set of genetic, physiological, psychological, and social causes whose influences and interconnections are best understood in an integrative evolutionary life history framework. Although there are multiple levels of mechanisms contributing to sex based disparities in mortality rates, the intensity of male mating competition in a population may have a crucial role in shaping the level of excess male mortality. The degree of variation and skew in male reproductive success may shape the intensity of male mating competition, leading to riskier behavioral and physiological strategies. This study examines three socio-demographic factors related to variation in human male reproductive success; polygyny, economic inequality, and the population ratio of reproductively viable men to women across nations with available data. The degrees of economic inequality and polygyny explained unique portions in the sex difference in mortality rates, these predictors accounted for 53% of the variance. The population ratio of reproductively viable men to women did not explain any additional variance. These results demonstrate the association between social conditions and health outcomes in modern nations, as well as the power of an evolutionary life history framework for understanding important social issues.
Understanding of Evolution May Be Improved by Thinking about People
Authors: Nettle Daniel
Published: July 2015

The theory of evolution is poorly understood in the population at large, even by those with some science education. The recurrent misunderstandings can be partly attributed to failure to distinguish between processes which individual organisms undergo and those which populations undergo. They may be so pervasive because we usually explain evolutionary ideas with examples from non-human animals, and our everyday cognition about animals does not track individuals as distinct from the species to which they belong. By contrast, everyday cognition about other people tracks unique individuals as well as general properties of humans. In Study 1, I present experimental evidence that categorization by species occurs more strongly for non-human animals than for other people in 50 British university students. In Study 2, I show, in the same population, that framing evolutionary scenarios in terms of people produces fewer conceptual errors than when logically identical scenarios are framed terms of non-human animals. I conclude that public understanding of evolution might be improved if we began instruction by considering the organisms which are most familiar to us.
Exploring the Evolved Concept of Newcomer: Experimental Tests of a Cognitive Model
Authors: Delton Andrew W. , Cimino Aldo
Published: July 2015

Enduring human coalitions face the adaptive problem of integrating new members. Although newcomers can provide benefits (e.g., additional labor), newcomers can also create costs (e.g., by free riding). Due to the unique adaptive problems they pose, we hypothesize that the mind contains an evolved concept of newcomer. We test the design of this concept experimentally and show that the activation of the newcomer concept elicits a variety of anti-free rider responses (e.g., a decrease in trust) with adaptively-targeted exceptions (e.g., a minimal increase in exclusion sentiment). These results support the hypothesis that the mind contains specialized concepts for understanding, creating, and sustaining intergenerational coalitions.
Understanding Suicide Terrorism: Premature Dismissal of the Religious-Belief Hypothesis
Authors: Liddle James R. , Machluf Karin , Shackelford Todd K.
Published: July 2015

We comment on work by Ginges, Hansen, and Norenzayan (2009) , in which they compare two hypotheses for predicting individual support for suicide terrorism: the religious-belief hypothesis and the coalitional-commitment hypothesis. Although we appreciate the evidence provided in support of the coalitional-commitment hypothesis, we argue that their method of testing the religious-belief hypothesis is conceptually flawed, thus calling into question their conclusion that the religious-belief hypothesis has been disconfirmed. In addition to critiquing the methodology implemented by Ginges et al., we provide suggestions on how the religious-belief hypothesis may be properly tested. It is possible that the premature and unwarranted conclusions reached by Ginges et al. may deter researchers from examining the effect of specific religious beliefs on support for terrorism, and we hope that our comments can mitigate this possibility.
Distinguishing between Perceiver and Wearer Effects in Clothing Color-Associated Attributions
Authors: Roberts S. Craig , Owen Roy C. , Havlicek Jan
Published: July 2015

Recent studies have noted positive effects of red clothing on success in competitive sports, perhaps arising from an evolutionary predisposition to associate the color red with dominance status. Red may also enhance judgments of women's attractiveness by men, perhaps through a similar association with fertility. Here we extend these studies by investigating attractiveness judgments of both sexes and by contrasting attributions based on six different colors. Furthermore, by photographing targets repeatedly in different colors, we could investigate whether color effects are due to influences on raters or clothing wearers, by either withholding from raters information about clothing color or holding it constant via digital manipulation, while retaining color-associated variation in wearer's expression and posture. When color cues were available, we found color-attractiveness associations when males were judged by either sex, or when males judged females, but not when females judged female images. Both red and black were associated with higher attractiveness judgments and had approximately equivalent effects. Importantly, we also detected significant clothing color-attractiveness associations even when clothing color was obscured from raters and when color was held constant by digital manipulation. These results suggest that clothing color has a psychological influence on wearers at least as much as on raters, and that this ultimately influences attractiveness judgments by others. Our results lend support for the idea that evolutionarily-derived color associations can bias interpersonal judgments, although these are limited neither to effects on raters nor to the color red.
Parent-Offspring Conflict over Mating: The Case of Mating Age
Authors: Apostolou Menelaos
Published: July 2015

Parents and offspring have asymmetrical preferences with respect to mate choice. So far, several areas of disagreement have been identified, including beauty, family background, and sexual strategies. This article proposes that mating age constitutes another area of conflict, as parents desire their children to initiate mating at a different age than the offspring desire it for themselves. More specifically, the hypothesis is tested that individuals prefer for their offspring to start having sexual relationships at a later age than they prefer for themselves to do so. Furthermore, it is hypothesized that individuals prefer to marry at a later age than they prefer their offspring to marry. Finally, the hypothesis is tested that parents prefer their daughters to marry at an earlier age and start sexual relationships later than their sons. Evidence from two independent studies employing 751 British parents provides support for all three hypotheses.
The Roman State and Genetic Pacification
Authors: Frost Peter
Published: July 2015

Over the last 10,000 years, the human genome has changed at an accelerating rate. The change seems to reflect adaptations to new social environments, including the rise of the State and its monopoly on violence. State societies punish young men who act violently on their own initiative. In contrast, non-State societies usually reward such behavior with success, including reproductive success. Thus, given the moderate to high heritability of male aggressiveness, the State tends to remove violent predispositions from the gene pool while favoring tendencies toward peacefulness and submission. This perspective is applied here to the Roman state, specifically its long-term effort to pacify the general population. By imperial times, this effort had succeeded so well that the Romans saw themselves as being inherently less violent than the “barbarians” beyond their borders. By creating a pacified and submissive population, the empire also became conducive to the spread of Christianity—a religion of peace and submission. In sum, the Roman state imposed a behavioral change that would over time alter the mix of genotypes, thus facilitating a subsequent ideological change.
Hooking up: Gender Differences, Evolution, and Pluralistic Ignorance
Authors: Reiber Chris , Garcia Justin R.
Published: July 2015

“Hooking-up” – engaging in no-strings-attached sexual behaviors with uncommitted partners - has become a norm on college campuses, and raises the potential for disease, unintended pregnancy, and physical and psychological trauma. The primacy of sex in the evolutionary process suggests that predictions derived from evolutionary theory may be a useful first step toward understanding these contemporary behaviors. This study assessed the hook-up behaviors and attitudes of 507 college students. As predicted by behavioral-evolutionary theory: men were more comfortable than women with all types of sexual behaviors; women correctly attributed higher comfort levels to men, but overestimated men's actual comfort levels; and men correctly attributed lower comfort levels to women, but still overestimated women's actual comfort levels. Both genders attributed higher comfort levels to same-gendered others, reinforcing a pluralistic ignorance effect that might contribute to the high frequency of hook-up behaviors in spite of the low comfort levels reported and suggesting that hooking up may be a modern form of intrasexual competition between females for potential mates.
Female Scarcity Reduces Women's Marital Ages and Increases Variance in Men's Marital Ages
Authors: Kruger Daniel J. , Fitzgerald Carey J. , Peterson Tom
Published: July 2015

When women are scarce in a population relative to men, they have greater bargaining power in romantic relationships and thus may be able to secure male commitment at earlier ages. Male motivation for long-term relationship commitment may also be higher, in conjunction with the motivation to secure a prospective partner before another male retains her. However, men may also need to acquire greater social status and resources to be considered marriageable. This could increase the variance in male marital age, as well as the average male marital age. We calculated the Operational Sex Ratio, and means, medians, and standard deviations in marital ages for women and men for the 50 largest Metropolitan Statistical Areas in the United States with 2000 U.S Census data. As predicted, where women are scarce they marry earlier on average. However, there was no significant relationship with mean male marital ages. The variance in male marital age increased with higher female scarcity, contrasting with a non-significant inverse trend for female marital age variation. These findings advance the understanding of the relationship between the OSR and marital patterns. We believe that these results are best accounted for by sex specific attributes of reproductive value and associated mate selection criteria, demonstrating the power of an evolutionary framework for understanding human relationships and demographic patterns.
The Evolutionary Significance of Red Sox Nation: Sport Fandom as a Byproduct of Coalitional Psychology
Authors: Winegard Benjamin , Deaner Robert O.
Published: July 2015

Sport fandom has received considerable attention from social scientists, yet few have considered it from an evolutionary perspective. To redress this gap, we develop the hypothesis that team sports exhibit characteristics that activate mechanisms which evolved to facilitate the development of coalitions in the context of small-scale warfare. Based on this by-product hypothesis, we predicted a correlation between fandom and binding (i.e. group-relevant) concerns, especially loyalty. To test this prediction, we administered the Sport Spectator Identification Scale (SSI) and the Moral Foundations Questionnaire (MFQ) to 495 undergraduates. The MFQ measures three binding concerns, including loyalty, and two individualizing ones, harm and fairness. As predicted, fandom correlated significantly with loyalty ( r = .27) and, within men, the two other binding concerns, authority ( r =.22) and purity ( r = .24). By contrast, fandom did not significantly correlate with harm or fairness. In addition, we predicted and found that men reported significantly higher levels of fandom (Cohen's d =.45) and loyalty ( d = .27) than did women. In conclusion, this study presents data supporting the coalitional by-product hypothesis of fandom and should spur further research using fandom as a window into our evolved psychology.
The Effect of Life Expectancy on Aggression and Generativity: A Life History Perspective
Authors: Dunkel Curtis S. , Mathes Eugene , Papini Dennis R.
Published: July 2015

Following a model that is inclusive of both dispositional and situational influences on life-history behaviors and attitudes, the effect of life expectancies on aggression and generativity was examined. Consistent with the hypotheses it was found that shorter life expectancies led to an increase in the desire to aggress and a decrease in the desire to engage in generative behaviors. The results are discussed in terms of how life history theory can be used to frame research on person-situation interactions.
Sexual Dimorphism in Stature (SDS), Jealousy and Mate Retention
Authors: Brewer Gayle , Riley Charlene
Published: July 2015

Previous research has investigated the manner in which absolute height impacts on jealousy and mate retention. Although relative height is also important, little information exists about the potential influence of sexual dimorphism in stature (SDS) within established relationships. The current study investigated the relationship between SDS and the satisfaction, jealousy and mate retention behaviors reported by men and women. Heterosexual men ( n = 98) and women ( n = 102) completed a questionnaire. Men in high SDS relationships reported the lowest levels of cognitive and behavioral jealousy, although the impact of SDS on relationship satisfaction was less clear. SDS was not associated with the overall use of mate retention strategies; SDS did however affect the use of three specific strategies (vigilance, monopolization of time, love and care). SDS did not affect women's relationship satisfaction, jealousy (cognitive, behavioral, or emotional) or the use of mate retention strategies (with the exception of resource display).
Parents Just Don't Understand: Parent-Offspring Conflict over Mate Choice
Authors: Dubbs Shelli L. , Buunk Abraham P.
Published: July 2015

Previous research reveals that children and parents are not in complete agreement over which traits are most important for the mate of the child. Children tend to prefer traits that suggest genetic quality, whereas parents prefer characteristics that suggest high parental investment and cooperation with the ingroup. Using a sample of parents, mothers ( n = 234) and fathers ( n =240) the hypothesis was supported; parents perceived characteristics indicating a lack of genetic quality as being more unacceptable to the child, while characteristics indicating a lack of parental investment and cooperation with the ingroup were more unacceptable to themselves. Sex differences between mothers and fathers and sons and daughters were explored.
Extending the Behavioral Immune System to Political Psychology: Are Political Conservatism and Disgust Sensitivity Really Related?
Authors: Tybur Joshua M. , Merriman Leslie A. , Hooper Ann E. Caldwell , McDonald Melissa M. , Navarrete Carlos David
Published: July 2015

Previous research suggests that several individual and cultural level attitudes, cognitions, and societal structures may have evolved to mitigate the pathogen threats posed by intergroup interactions. It has been suggested that these anti-pathogen defenses are at the root of conservative political ideology. Here, we test a hypothesis that political conservatism functions as a pathogen-avoidance strategy. Across three studies, we consistently find no relationship between sensitivity to pathogen disgust and multiple measures of political conservatism. These results are contrasted with theoretical perspectives suggesting a relationship between conservatism and pathogen avoidance, and with previous findings of a relationship between conservatism and disgust sensitivity.
High Religiosity and Societal Dysfunction in the United States during the First Decade of the Twenty-First Century
Authors: Delamontagne R. Georges
Published: July 2015

This study provides independent empirical evidence that bears upon the truth or falsity of recently formulated hypotheses regarding reciprocal relationships between levels of religiosity and societal dysfunction. Gregory S. Paul's findings, published in the Journal of Religion and Society (2005), Free Inquiry (2008), and Evolutionary Psychology (2009), have demonstrated that high degrees of theism are associated with high degrees of societal dysfunction among the prosperous democracies. Whereas his research employs numerous scatter diagrams and bivariate correlations involving measures of religiosity and societal dysfunction pertaining to 17 nation states, the current study's units of analysis are the 50 states and the District of Columbia. Additionally, the utilization of multiple regression analysis allows the detection of the effects of other potentially relevant explanatory variables, such as educational attainment, income level, and race. The findings are only minimally supportive of Paul's hypotheses regarding the contributions of high religiosity to societal dysfunction and to the effects of societal dysfunction upon religiosity. Simultaneously, the results of correlational and regression analyses attest to the more substantial explanatory power of the social inequality variables of education, income, and race. Accordingly, it is argued that “American Exceptionalism,” when understood as referring to a society manifesting the coexistence of high levels of theism and high levels of societal dysfunction, is best explained by the United States' high degree of social inequality, compared with other modern industrialized democracies.
The Effects of Control of Resources on Magnitudes of Sex Differences in Human Mate Preferences
Authors: Moore Fhionna , Cassidy Clare , Perrett David I.
Published: July 2015

We tested the hypothesis that magnitudes of sex differences in human mate preferences would be inversely related to control of resources. Specifically, we predicted that the ideal partner age, maximum and minimum partner ages tolerated and preferences for “physical attractiveness” over “good financial prospects” of female participants would approach parity with that of men with increasing control of resources. In a sample of 3770 participants recruited via an online survey, the magnitudes of sex differences in age preferences increased with resource control whereas the sex difference in preferences for “physical attractiveness” over “good financial prospects” disappeared when resource control was high. Results are inconsistent, and are discussed in the context of adaptive tradeoff and biosocial models of sex differences in human mate preferences.
Evidence for Menstrual Cycle Shifts in Women's Preferences for Masculinity: A Response to Harris (in Press) “Menstrual Cycle and Facial Preferences Reconsidered”
Authors: DeBruine Lisa , Jones Benedict C. , Frederick David A. , Haselton Martie G. , Penton-Voak Ian S. , Perrett David I.
Published: July 2015

Over the last decade, a growing literature has shown that women in the fertile phase of the menstrual cycle demonstrate stronger preferences for men with masculine traits than they do when in the non-fertile phases of the cycle (see Gangestad and Thornhill, 2008 and Jones et al., 2008 for recent reviews). In a recent article, Harris (in press; Sex Roles) failed to replicate this increase in women's preferences for masculine faces when women are near ovulation. Harris represented her study as one of only three studies on the topic, and as the largest of the existing studies. There are, however, many more studies on menstrual cycle shifts in preferences for facial masculinity in the published literature, including one that is 2.5 times larger in size than the Harris study. In this article, we review the evidence for cyclic shifts in mate preferences and related behaviors and discuss weaknesses of Harris's methods. Considered as a whole, the evidence for menstrual cycle shifts in women's preferences and behaviors is compelling, despite the failure of replication reported by Harris.
Grandparental Child Care in Europe: Evidence for Preferential Investment in More Certain Kin
Authors: Danielsbacka Mirkka , Tanskanen Antti O. , Jokela Markus , Rotkirch Anna
Published: July 2015

Theories of kin selection and parental investment predict stronger investment in children and grandchildren by women and maternal kin. Due to paternity uncertainty, parental and grandparental investments along paternal lineages are based on less certain genetic relatedness with the children and grandchildren. Additionally, the hypothesis of preferential investment (Laham, Gonsalkorale, and von Hippel, 2005) predicts investment to vary according to available investment options. Two previous studies have tested this hypothesis with small samples and conflicting results. Using the second wave of the large and multinational Survey of Health, Ageing and Retirement in Europe (SHARE), collected in 2006–07, we study the preferential investment hypothesis in contemporary Europe based on self-reported grandparental provision of child care. We predict that 1) maternal grandmothers provide most care for their grandchildren, followed by maternal grandfathers, paternal grandmothers and last by paternal grandfathers; 2) maternal grandfathers and paternal grandmothers provide equal amounts of care when the latter do not have grandchildren via a daughter; 3) women who have grandchildren via both a daughter and a son will look after the children of the daughter more; and 4) men who have grandchildren via both a daughter and a son will look after the children of the daughter more. Results support all four hypotheses and provide evidence for the continuing effects of paternity uncertainty in contemporary kin behavior.
Recognition of Novel Faces after Single Exposure is Enhanced during Pregnancy
Authors: Anderson Marla V. , Rutherford M.D.
Published: July 2015

Protective mechanisms in pregnancy include Nausea and Vomiting in Pregnancy (NVP) ( Fessler, 2002 ; Flaxman and Sherman, 2000 ), increased sensitivity to health cues ( Jones et al., 2005 ), and increased vigilance to out-group members (Navarette, Fessler, and Eng, 2007). While common perception suggests that pregnancy results in decreased cognitive function, an adaptationist perspective might predict that some aspects of cognition would be enhanced during pregnancy if they help to protect the reproductive investment. We propose that a reallocation of cognitive resources from nonessential to critical areas engenders the cognitive decline observed in some studies. Here, we used a recognition task disguised as a health rating to determine whether pregnancy facilitates face recognition. We found that pregnant women were significantly better at recognizing faces and that this effect was particularly pronounced for own-race male faces. In human evolutionary history, and today, males present a significant threat to females. Thus, enhanced recognition of faces, and especially male faces, during pregnancy may serve a protective function.
Voice Pitch Influences Perceptions of Sexual Infidelity
Authors: O'Connor Jillian J.M. , Re Daniel E. , Feinberg David R.
Published: July 2015

Sexual infidelity can be costly to members of both the extra-pair and the paired couple. Thus, detecting infidelity risk is potentially adaptive if it aids in avoiding cuckoldry or loss of parental and relationship investment. Among men, testosterone is inversely related to voice pitch, relationship and offspring investment, and is positively related to the pursuit of short-term relationships, including extra-pair sex. Among women, estrogen is positively related to voice pitch, attractiveness, and the likelihood of extra-pair involvement. Although prior work has demonstrated a positive relationship between men's testosterone levels and infidelity, this study is the first to investigate attributions of infidelity as a function of sexual dimorphism in male and female voices. We found that men attributed high infidelity risk to feminized women's voices, but not significantly more often than did women. Women attributed high infidelity risk to masculinized men's voices at significantly higher rates than did men. These data suggest that voice pitch is used as an indicator of sexual strategy in addition to underlying mate value. The aforementioned attributions may be adaptive if they prevent cuckoldry and/or loss of parental and relationship investment via avoidance of partners who may be more likely to be unfaithful.
Preliminary Evidence that the Limbal Ring Influences Facial Attractiveness
Authors: Peshek Darren , Semmaknejad Negar , Hoffman Donald , Foley Pete
Published: July 2015

The limbal ring of the eye appears as a dark annulus where the iris meets the sclera. Both width and opacity of the limbal ring are influenced by iris pigmentation and optical properties of the region. With age the limbal ring becomes less prominent, making it a probabilistic indicator of youth and health. This raises the question: Are judgments of facial attractiveness sensitive to this signal in a potentially adaptive way? Here we show that the answer is yes. For male and female observers, both male and female faces with a dark and distinct limbal ring are rated as more attractive than otherwise identical faces with no limbal ring. This result is observed not just for upright faces but also for inverted faces, suggesting that the limbal ring is processed primarily as a local feature rather than as a configural feature in the analysis of facial beauty. We also discuss directions for future research that can clarify the role of the limbal ring in the visual perception of facial attractiveness.