Among the various physical traits that serve as secondary sexual characteristics, breasts and buttocks are visually conspicuous cues used in male mate evaluation because they signal youth, fertility, developmental stability, and nutritional status. Although these features have been extensively studied, less is known about the extent to which men differ in the relative importance they place on each trait. Latent Profile Analysis (LPA) identified distinct subgroups of Norwegian men (N = 395) based on how much importance they placed on breasts and buttocks in their evaluations of romantic partners. A four-class solution emerged, comprising Highly Body-Oriented (53%), Moderately Body-Oriented (20%), Buttocks-Oriented (18%), and Body-Unoriented (9%) subgroups. Predictors such as egalitarianism, materialism, and preferences for sexiness were, as expected, significantly associated with class membership, providing support for the validity of the typology. Notably, a consistent buttocks-oriented class emerged across all LPA solutions, whereas no distinct breasts-oriented group was found, as ratings of breasts persistently co-occurred with high ratings of buttocks, suggesting that breasts do not function as a primary preference in isolation. These findings reveal that buttocks may occupy a more central and stable role than breasts in male mate preferences, offering novel insights into the structure of physical attraction and heterogeneity in the male mating mind.

We tested the adaptive hypothesis of psychopathy in human and computer Prisoner Dilemma (PD) matches. From a cohort of 448 male undergraduates who completed the Levenson Self-Report Psychopathy Scale (LSRP), 31 high psychopathic (PP) and 29 low PP students, sampled from upper and lower quartiles of the cohort, played a 40-round PD match in which real money was at stake. The human matches were of three kinds: Low PP versus Low PP, Low PP versus High PP, and High PP versus High PP. In computer simulations, the empirical defection probabilities from High and Low PP human players were entered in a three-player round-robin match with tit-for-tat (TFT) or a less cooperative variant. The strategies proliferated or dwindled in subsequent generations in proportion to their winnings and the matches continued until two players became extinct. In the human matches, High PP players had higher earnings in matches with Low PP and lower earnings in matches with other High PP players. In the computer matches, TFT drove both Low PP and High PP to extinction. However, High PP drove both Low PP and a less cooperative variant of TFT to extinction. Our experiments showed that PP traits may proliferate in two ways. People with low psychopathy engage in selfish behaviors also and people with high psychopathy are capable of cooperation and deter defection by means of harsh punishment. The broader significance of the in silico experiment is that randomness in social encounters may allow behavioral expressions of psychopathy to thrive over an altruistic and reciprocal strategy such as TFT.

Evolutionary theorizing predicts that parenthood is associated with higher hedonic wellbeing (experiencing more positive and fewer negative emotions), higher eudaimonic wellbeing (experiencing greater meaning in life), and greater life satisfaction. To test this hypothesis, we analyzed a dataset comprising 5,556 participants drawn from 10 different nations. We found a small positive effect of parenthood on eudaimonic wellbeing, which was more pronounced for women. Conversely, we found virtually no differences between parents and nonparents across all measured dimensions of hedonic wellbeing and life satisfaction. Furthermore, for most dimensions, we did not detect significant interactions between parenthood status and sex, age, or relationship status. Additionally, participants with children reported lower relationship satisfaction than those without children; however, the observed difference was small. Our results contrast with evolutionary predictions, as well as empirical findings showing that parents perceive their children as sources of positive emotions and life purpose, creating a paradox for which we offer a possible resolution.

Ornamentation is a widespread feature of human material culture, yet its preference varies across societies. We tested the hypothesis that variation in ornamentation preference correlates with socioecological factors, comparing 215 parent–child dyads from three societies differing in WEIRD characteristics: Scotland, Pakistan, and Papua New Guinea. We found that less WEIRD societies exhibit stronger preferences for ornamentation, consistent with adaptive socioecological influences on aesthetic valuation. Moreover, a decline in ornamentation preference with age was observed only in the Western sample, suggesting cultural suppression of ornamentation across development. These findings support the view that children's aesthetic preferences may more closely reflect evolved, foundational biases toward ornamentation, which are subsequently modulated by cultural context. Investigating such developmental trajectories is crucial to understanding the biological basis and evolutionary origins of human aesthetic preferences.

The fully revised fifth edition of this highly acclaimed undergraduate textbook provides a thought-provoking introduction to evolutionary psychology, while assuming no prior knowledge of evolutionary theory. The authors continue to carefully guide students towards a level of understanding where they can critically apply evolutionary theory to psychological explanation, providing an engaging and balanced discussion of the field. New material has been added on female homosexuality, artificial intelligence and language, cooking and human brain expansion, Covid-19 and rates of evolutionary change, and the effects of digital media on mental health. This edition also has new and revised boxed case studies, many new figures, extra discussion questions, and additional further reading suggestions. The text is accompanied by online resources including an updated test bank and lecture slides, as well as new answers to the end-of-chapter questions. This is essential reading for students taking undergraduate and graduate courses in evolutionary psychology.

The fully revised fifth edition of this highly acclaimed undergraduate textbook provides a thought-provoking introduction to evolutionary psychology, while assuming no prior knowledge of evolutionary theory. The authors continue to carefully guide students towards a level of understanding where they can critically apply evolutionary theory to psychological explanation, providing an engaging and balanced discussion of the field. New material has been added on female homosexuality, artificial intelligence and language, cooking and human brain expansion, Covid-19 and rates of evolutionary change, and the effects of digital media on mental health. This edition also has new and revised boxed case studies, many new figures, extra discussion questions, and additional further reading suggestions. The text is accompanied by online resources including an updated test bank and lecture slides, as well as new answers to the end-of-chapter questions. This is essential reading for students taking undergraduate and graduate courses in evolutionary psychology.

The fully revised fifth edition of this highly acclaimed undergraduate textbook provides a thought-provoking introduction to evolutionary psychology, while assuming no prior knowledge of evolutionary theory. The authors continue to carefully guide students towards a level of understanding where they can critically apply evolutionary theory to psychological explanation, providing an engaging and balanced discussion of the field. New material has been added on female homosexuality, artificial intelligence and language, cooking and human brain expansion, Covid-19 and rates of evolutionary change, and the effects of digital media on mental health. This edition also has new and revised boxed case studies, many new figures, extra discussion questions, and additional further reading suggestions. The text is accompanied by online resources including an updated test bank and lecture slides, as well as new answers to the end-of-chapter questions. This is essential reading for students taking undergraduate and graduate courses in evolutionary psychology.

The fully revised fifth edition of this highly acclaimed undergraduate textbook provides a thought-provoking introduction to evolutionary psychology, while assuming no prior knowledge of evolutionary theory. The authors continue to carefully guide students towards a level of understanding where they can critically apply evolutionary theory to psychological explanation, providing an engaging and balanced discussion of the field. New material has been added on female homosexuality, artificial intelligence and language, cooking and human brain expansion, Covid-19 and rates of evolutionary change, and the effects of digital media on mental health. This edition also has new and revised boxed case studies, many new figures, extra discussion questions, and additional further reading suggestions. The text is accompanied by online resources including an updated test bank and lecture slides, as well as new answers to the end-of-chapter questions. This is essential reading for students taking undergraduate and graduate courses in evolutionary psychology.

An increasing number of people are single, meaning that they do not have an intimate partner. Existing research has focused on identifying the difficulties that people face in attracting mates. In the present paper, we propose that another factor contributing to singlehood is experiencing difficulties in maintaining intimate relationships. By analyzing data collected from 1099 Greek-speaking participants, we found that individuals who experienced greater difficulties maintaining intimate relationships were more likely to be either between-relationships single or voluntarily single rather than in an intimate relationship. For women specifically, higher scores in this dimension were also associated with a greater probability of being in an intimate relationship than being involuntarily single. Additionally, we found that the association between difficulties in maintaining an intimate relationship and relationship status was linear for men—the relationship between the two variables can be pictured as straight line—but curvilinear—the relationship can be pictured as an inverted U-shaped curve—for women.

Researchers have suggested that men with more masculine facial characteristics have stronger immune systems but are perceived to be less likely to invest resources in partners and offspring. How women resolve this putative trade-off between the costs and benefits of choosing a masculine mate have previously been reported to be associated with women's openness to uncommitted relationships (i.e., their sociosexuality) and self-perceived mate value. However, not all studies have reported these links and the methods used to assess masculinity preferences in studies reporting these patterns of results (forced-choice tests using stimuli in which masculinity was experimentally manipulated) have recently been criticized for having low ecological validity. Consequently, we tested whether sociosexuality or self-perceived mate value predicted women's masculinity preferences when masculinity preferences were assessed using ratings of individual natural (i.e., unmanipulated) male faces. Our analyses show no evidence that individual differences in women's sociosexuality or self-perceived mate value significantly predicted masculinity preferences. Thus, our results do not support the proposal that sociosexuality and/or self-perceived mate value are important sources of individual differences in women's preferences for male facial masculinity.