Adaptive Human Behavior and Physiology最新文献

Objective

Why do dominant leaders rise to power via the popular vote? This research tests whether when people feel threatened by intra-group disorder they desire stronger, more dominant leaders.

Methods

Participants (N = 1,026) read a vignette that depicts a within-group norm violation. We then used a between-subjects design to randomly assign participants to a specific version of the vignette in which (a) a focal target individual in the scenario varied in their dominance (punitiveness: from no to moderate to strong); and (b) the local group faced little or substantial intra-group conflict and disorder (threat: from low to high). Following this, participants reported how much they endorse the target individuals as leader and the individual’s perceived prestige.

Results

We find that intra-group conflict motivates a psychology that favors the rise of dominant leaders: Highly punitive individuals (seen as highly dominant) are endorsed as leaders when in-group threat is high, but comparably disfavored when threat is low. Under low threat, non-punitive individuals (who are seen as less dominant) are endorsed as leaders. Subsequent analyses reveal that these shifts in leader preferences are explained by corresponding changes in prestige. Under conditions of high threat, dominance confers prestige, whereas under low threat, dominance suppresses prestige. Tests of mediation further show that the effect of dominance on increased leader support under high threat is mediated by prestige.

Conclusions

In contexts of threat, such as internal disorder, dominant leaders are favored and gain prestige, owing to their perceived ability to supply benefits such as in mediating internal conflicts.

Abstract

Objective

Caring, sensitive parenting is known to be associated with higher levels of engagement in support-seeking behaviors among children and young adolescents. However, no study has yet explored the role of perceived parental attention in social support seeking in early adulthood. Growing evidence suggests that the µ-opioid receptor gene polymorphism (OPRM1 A118G) moderates one’s responsiveness to social environments. Prompted by the differential susceptibility theory of gene–environment interaction, the present study examined whether the OPRM1 polymorphism would moderate the association between perceived parental attention and social support seeking in early adulthood.

Methods

Six hundred and twenty Japanese undergraduate students self-reported the amount of attention they subjectively perceived their parents to have given them during childhood and completed scales that assess support-seeking behaviors. Clippings of their fingernails were collected for genotyping.

Results

The results showed that the interactive effect of perceived parental attention and OPRM1 genotypes on social support seeking was significant. Specifically, perceived parental attention only significantly and positively predicted OPRM1 GG carriers’ social support seeking in response to stress.

Conclusions

The findings support the view that OPRM1 polymorphism moderates the association between early experiences and developmental outcomes.

Objectives

A paradox exists in research on girls and women. On the one hand, they behave in a more egalitarian fashion than their male counterparts. On the other hand, status increases their own and their children’s survival.

Methods

Evidence from non-human primates can help reconcile these findings. In species that do not reside with female kin for life, females are relatively egalitarian and individualistic. They typically do not cooperate or engage in direct competition and exhibit little tolerance for status differentials.

Results and Conclusions

Women follow this pattern. While a husband’s status and her female relatives’ support enhance a woman’s status and reproductive success, her own actions too influence her access to resources and allies. Evidence on girls’ and women’s same-sex competition and quests for status supports the hypothesis that human females inhabit dispersal-egalitarian communities in which competition is avoided, an egalitarian ethos prevails, competitive behavior is disguised, and status differentials are not tolerated.

Objective

The dual-hormone hypothesis (DHH) posits that some effects of testosterone on human behavior and psychology related to status-seeking are moderated by cortisol, such that they are stronger when cortisol levels are low. In support of the DHH, studies have found that cortisol negatively moderated the relationship between testosterone and such traits as status-seeking and interest in uncommitted sex. Others indicate a positive moderating influence of cortisol in some cases. Here, we test whether two psychosexual indices—sexual desire and sociosexuality—meet the expectations of the DHH in a large sample of men and women.

Method

646 women and 185 men attended lab sessions during which they provided saliva samples for hormonal analysis and responded to the Sociosexual Orientation Inventory-Revised and the Sexual Desire Inventory (180 women and 43 men returned for a second session approximately two months later). We quantified salivary hormone concentrations using ELISA and assessed within- and between-participant effects of hormones on psychosexual measures with mixed-effects models.

Results

We observed a positive interaction between within-subjects cortisol and testosterone in models of sexual desire in both men and women. For women, these effects emerged in models of general sexual desire and in models of the dyadic desire subscale and were robust to many analytical configurations. For men, the effects were limited to models of solitary desire, but were also robust to alternative analyses. We present data to quantify our risks of both type I and type II error.

Conclusions

Some of our results contrast with usual dual-hormone hypothesis predictions of negative interactions between testosterone and cortisol. We suggest several potential explanations for these results, including a positive feedback loop whereby elevated testosterone prompts increases in sexual desire and behavior, necessitating cortisol-induced mobilization of energy stores.

Objective

Research has demonstrated that men prefer women’s voices with higher pitch and that women’s voices recorded at high compared to low fertility phases of the menstrual cycle are rated as more attractive. These findings suggest that voice conveys information relevant to reproductive success. Because voice attractiveness is higher during the high fertility phase and voice pitch positively predicts attractiveness ratings, it has been hypothesized that cyclical changes in vocal attractiveness are driven by changes in voice pitch. However, attempts to detect acoustic changes have produced mixed results. With the higher degree of ecological validity achieved by including social context (simulated interactions with men and women) and by recording voice in the three phases of menstrual cycles, the present study addresses limitations of previous research.

Methods

Forty-eight naturally cycling women were recorded during the menstrual, late follicular (high fertility), and luteal phases while leaving voice messages to masculinized and femininized men and women.

Results

No cycle-related changes in pitch and pitch variability for the recordings directed to masculinized and femininized men and women were detected. By including relationship status as predictor in additional models, higher-order interaction effects showed that single and partnered women displayed opposite cycle-related pitch changes directed only to women, but not men.

Conclusion

The cycle-related voice changes found in the present study do not support the hypothesis that cyclic pitch variations represent an adaptive mechanism for attracting partners. We discuss cyclic changes in voice pitch in relation to intrasexual competition by taking into an account that the present study is likely underpowered for adequate testing of the complex higher-order interactions.

Objectives

This study tested whether genetically predicted trait-body mass index (trait-BMI) was linked to more general daily discrimination among older adults, and consequently to decline in their life satisfaction.

Methods

Data were from the Health and Retirement Study, nationally representative of U.S. adults over 50. Genetic prediction models were used to extract the trait component of BMI, which was then deployed in regression models for discrimination. A recently developed “regression with residuals” approach was used to test associations with subsequent change in life satisfaction.

Results

Genetically predicted trait-BMI was linked to more general discrimination reports. It also had negative associations with change in life satisfaction—linkages not consistently or strongly mediated by discrimination.

Conclusions

Trait-BMI—arguably resistant to sustained alteration through individual efforts—seems linked to decline in older adults’ life satisfaction. General daily discrimination, however, may not be an important mechanism.

Objective

Trait mate value covaries with several socio-political attitudes. One’s dating popularity in a mating market can, however, shift one’s self-perceived mate value in that market. We tested whether dating popularity could therefore also shift socio-political attitudes, and whether trait mate value could moderate this effect.

Method

Heterosexual participants (N = 237) reported their trait mate value. Participants then recorded a video of themselves and received video responses from five opposite-sex peers, each consisting of either positive or negative romantic feedback—forming the manipulation (popularity: from low to high). Afterwards, we measured participants’ attitudes to traditional gender roles, casual sex, minimum wage and healthcare, and implicit sexual and political attitudes.

Results

Unpopular men reported less support for casual sex than popular men. There was no main effect on women. Unpopular men had lower positive affect than popular men, and in turn men with lower positive affect reported less support for casual sex and for increasing the minimum wage and access to healthcare than men with higher positive affect. Unpopular low mate-value women reported more support for casual sex than popular low mate-value women. Unpopular men of low and average mate value reported less support for casual sex than popular men of low and average mate value. There was no effect on average mate-value women and high mate-value women and men.

Conclusions

Changes in positive affect due to dating popularity influence some of men’s, but not women’s, socio-political attitudes, and trait mate value moderates the effects of popularity on attitudes to casual sex.

The goal of the special issue on “Sports science: evolutionary perspectives and biological mechanisms” was to build a bridge to help the development of a coherent and unifying approach to the study of sport science within an evolutionary framework. By focusing specifically on the biological and psychological dynamics of sport performance and competition, we asked if sports can be used to study the evolution of human behavior, biology and psychology. Likewise, we asked whether this evolutionary approach could improve our understandings of the physical and psychological limits of human athletic performance and health.