Environmental Unpredictability in Childhood Is Associated With Anxious Romantic Attachment and Intimate Partner Violence Perpetration

Human life history theory describes how resources are allocated among conflicting life tasks, including trade-offs concerning reproduction. The current research investigates the unique importance of environmental unpredictability in childhood in association with romantic attachment, and explores whether objective or subjective measures of environmental risk are more informative for testing life history hypotheses. We hypothesize that (1) unpredictability in childhood will be associated with greater anxious attachment, (2) anxious attachment will be associated with intimate partner violence (IPV) perpetration, and (3) anxious attachment will mediate the relationship between unpredictability in childhood and IPV perpetration. In two studies (total n = 391), participants in a heterosexual, romantic relationship completed self-report measures of childhood experiences, romantic attachment, and IPV perpetration. Study 1 provides support for Hypothesis 1. Hypothesis 1 is replicated only for men, but not women, in Study 2. Results of Study 2 provide support for Hypothesis 2 for men and women, and Hypothesis 3 was supported for men but not women. The findings contribute to the literature addressing the association of environmental risk in childhood on adult romantic relationship outcomes.

Life history correlates of human (Homo sapiens) ejaculate quality

Life history strategies reflect resource allocation decisions, which manifest as physiological, psychological, and behavioral traits. We investigated whether human ejaculate quality is associated with indicators of relatively fast (greater resource allocation to mating effort) or slow (greater resource allocation to parenting effort) life history strategies in a test of two competing hypotheses: (a) The phenotype-linked fertility hypothesis, which predicts that men pursuing a relatively fast life history strategy will produce higher quality ejaculates, and (b) the cuckoldry-risk hypothesis, which predicts that men pursuing a relatively slow life history strategy will produce higher quality ejaculates. Men (n = 41) completed a self-report measure assessing life history strategy and provided two masturbatory ejaculate samples. Results provide preliminary support for the cuckoldry-risk hypothesis: Men pursuing a relatively slow life history strategy produced higher quality ejaculates. Ejaculate quality may therefore reflect resource allocation decisions for greater parenting effort, as opposed to greater mating effort. The findings contribute informative data on correlations between physiological and phenotypic indicators of human life history strategies. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Paternity data and relative testes size as measures of level of sperm competition in the Cercopithecoidea

Historically, the empirical study of the role of sperm competition in the evolution of sexual traits has been problematic through an enforced reliance on indirect proxy measures. Recently, however, a procedure was developed that uses paternity data to measure sperm competition level directly in terms of males/conception (i.e., the number of males that have sperm present in a female's ampulla at conception). When tested on apes and humans (Hominoidea) this measure proved not only to correlate significantly with the traditionally used measure of relative testes size but also to offer a number of advantages. Here we provide a second test of the procedure, this time using paternity data for the Old World monkeys (Cercopithecoidea). We calculate sperm competition levels (males/conception) for 17 species of wild and free-ranging cercopithecoids and then analyze the data against measures of relative testes size. Calculated sperm competition levels correlate strongly with relative testes size both with and without phylogenetic control at both the species and generic levels. The signal-to-noise ratios inherent in both the past measure of relative testes size and the new measure of sperm competition level from paternity data are discussed. We conclude that although both measures are appropriate for the future study of the role of sperm competition in the evolution of sexual traits, when paternity data are available they provide the more direct and meaningful analytical tool. Not least, they potentially allow a first empirical analysis of the role of sperm competition in the evolution of relative testes size that could then be compared with the wealth of theoretical analyses that already exist.

Associations of Attachment Anxiety and Avoidance With Male- and Female-Perpetrated Sexual Coercion in Romantic Relationships

Few studies have investigated the associations between romantic attachment dimensions and sexual coercion perpetration. The present study aimed to address methodological limitations in previous studies, and to more accurately identify the associations between romantic attachment and sexual coercion perpetration in romantic relationships. Data from 284 individuals (56% men) were secured via an online self-report survey. Participants completed assessments of romantic attachment to their current romantic partner, and reported the frequency with which they perpetrated 34 acts of sexual coercion against their romantic partner. Attachment anxiety was a positive predictor of sexual coercion perpetration for men and women. Additionally, for men only, the association between attachment anxiety and sexual coercion perpetration was stronger for individuals with greater attachment avoidance. The results of the study present a clearer picture of the associations between attachment and sexual coercion, and accord with modern theoretical perspectives positing that romantic attachment regulates reactions to acute and ongoing relationship threats.

Do Men Produce Higher Quality Ejaculates When Primed With Thoughts of Partner Infidelity?

Sperm competition theory can be used to generate the hypothesis that men alter the quality of their ejaculates as a function of sperm competition risk. Using a repeated measures experimental design, we investigated whether men produce a higher quality ejaculate when primed with cues to sperm competition (i.e., imagined partner infidelity) relative to a control prime. Men ( n = 45) submitted two masturbatory ejaculates-one ejaculate sample for each condition (i.e., sperm competition and control conditions). Ejaculates were assessed on 17 clinical parameters. The results did not support the hypothesis: Men did not produce higher quality ejaculates in the sperm competition condition relative to the control condition. Despite the null results of the current research, there is evidence for psychological and physiological adaptations to sperm competition in humans. We discuss methodological limitations that may have produced the null results and present methodological suggestions for research on human sperm competition.

Endorsement of Social and Personal Values Predicts the Desirability of Men and Women as Long-Term Partners

A prospective romantic partner's desirability as a long-term partner may be affected by the values that he or she endorses. However, few studies have examined the effects of "values" on a person's desirability as a long-term partner. We hypothesized that individuals who endorse social values (vs. personal values) will be perceived as more desirable long-term partners (Hypothesis 1) and that the endorsement of social values will be especially desirable in a male (vs. female) long-term partner (Hypothesis 2). The current study employed a 2 (sex of prospective partner: male vs. female) × 2 (values of prospective partner: personal vs. social) × 2 (physical attractiveness of prospective partner: unattractive vs. highly attractive) mixed-model design. Participants were 339 undergraduates (174 men, 165 women), with ages varying between 18 and 33 years ( M = 19.9, SD = 3.6), and mostly in a romantic relationship (53.7%). Participants reported interest in a long-term relationship with prospective partners depicted in four scenarios (within subjects), each varying along the dimensions of values (personal vs. social) and physical attractiveness (unattractive vs. highly attractive). Individuals endorsing personal values (vs. social values) and men (vs. women) endorsing personal values were rated as less desirable as long-term partners. The current research adds to the partner preferences literature by demonstrating that an individual's ascribed values influence others' perceptions of desirability as a long-term partner and that these effects are consistently sex differentiated, as predicted by an evolutionary perspective on romantic partner preferences.

Post-Fight Respect Signals Valuations of Opponent's Fighting Performance

The current research explores whether humans process inputs about combat (e.g., assessments of formidability) that produce outputs of post-fight respect (e.g., shaking an opponent's hand when the fight ends). Using an online questionnaire (Study 1, n = 132), an in-person questionnaire (Study 2, n = 131), and an in-lab fight simulation (Study 3, n = 58), we investigated whether participants were more likely to receive (Studies 1 and 3) and display (Studies 2 and 3) post-fight respect as a function of the fight outcome (Hypothesis 1), use of fight tactics (Hypothesis 2), fighter asymmetries (Hypothesis 3), fighter ranking (Hypothesis 4), and the presence of witnesses (Hypothesis 5). The results support Hypotheses 1 to 4 concerning expectations of receiving post-fight respect, and support only Hypotheses 2 and 3 concerning displays of post-fight respect. We suggest that post-fight respect signals positive valuations of fighting performance that may function to maintain valuable relationships within the social group.

Consideration of Cosmetic Surgery As Part of Women's Benefit-Provisioning Mate Retention Strategy

Individuals perform mate retention behaviors to minimize the risk of partner infidelity and relationship dissolution. The current study investigates whether consideration of cosmetic surgery can be conceptualized as part of a broader strategy of mate retention for women, but not men. We hypothesized that women's consideration of cosmetic surgery would be positively associated with performance frequencies of Benefit-Provisioning and Cost-Inflicting mate retention behaviors. We recruited 203 individuals (54% women) in committed heterosexual relationships from Tehran, Iran. Results indicate a positive association between consideration of cosmetic surgery and Benefit-Provisioning mate retention behaviors for women, but not men. There was no association between consideration of cosmetic surgery and Cost-Inflicting mate retention behaviors. Women therefore may consider cosmetic surgery to improve their physical attractiveness as part of a Benefit-Provisioning strategy to retain a long-term mate. We discuss limitations of the study and highlight future directions for research from an evolutionary perspective.

Cross-Cultural Investigation of Male Gait Perception in Relation to Physical Strength and Speed

Previous research documents that men and women can accurately judge male physical strength from gait, but also that the sexes differ in attractiveness judgments of strong and weak male walkers. Women's (but not men's) attractiveness assessments of strong male walkers are higher than for weak male walkers. Here, we extend this research to assessments of strong and weak male walkers in Chile, Germany, and Russia. Men and women judged videos of virtual characters, animated with the walk movements of motion-captured men, on strength and attractiveness. In two countries (Germany and Russia), these videos were additionally presented at 70% (slower) and 130% (faster) of their original speed. Stronger walkers were judged to be stronger and more attractive than weak walkers, and this effect was independent of country (but not sex). Women tended to provide higher attractiveness judgments to strong walkers, and men tended to provide higher attractiveness judgments to weak walkers. In addition, German and Russian participants rated strong walkers most attractive at slow and fast speed. Thus, across countries men and women can assess male strength from gait, although they tended to differ in attractiveness assessments of strong and weak male walkers. Attractiveness assessments of male gait may be influenced by society-specific emphasis on male physical strength.

Rethinking the transmission gap: What behavioral genetics and evolutionary psychology mean for attachment theory: A comment on Verhage et al. (2016)

Traditional attachment theory posits that attachment in infancy and early childhood is the result of intergenerational transmission of attachment from parents to offspring. Verhage et al. (2016) present meta-analytic evidence addressing the intergenerational transmission of attachment between caregivers and young children. In this commentary, we argue that their appraisal of the behavioral genetics literature is incomplete. The suggested research focus on shared environmental effects may dissuade the pursuit of profitable avenues of research and may hinder progress in attachment theory. Specifically, further research on the "transmission gap" will continue to limit our understanding of attachment etiology. We discuss recent theoretical developments from an evolutionary psychological perspective that can provide a valuable framework to account for the existing behavioral genetic data. (PsycINFO Database Record