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The current research investigates the employment outcomes of Career Technical Education (CTE) from California community colleges. We used three years of data from the California Community C...

Romantic relationships with a large age difference between partners are judged to be less acceptable, more disgusting, and less likely to succeed than age-similar relationships. We investigated the role of strategic moralization in condemnation of man-older age-discrepant relationships. We hypothesized that (1) this condemnation promotes self-serving interests of those who stand to lose from violation of age-based assortative mating, and (2) endorsement of prostitution mediates the association between participant's age and condemnation of man-older age-discrepant relationships because these relationships make the exchange of sex for resources explicit and acceptable. Using self-reports from 430 participants, we documented that endorsement of prostitution mediates the association between age and condemnation of man-older age-discrepant relationships for women but not men.

Coalitional mate retention (CMR) occurs when individuals request assistance from a friend to minimize the risk of partner infidelity. We secured reports from men and women in a committed, heterosexual relationship to investigate associations between CMR requests and the sex and personality traits of individuals who request CMR and the sex of their friends. Consistent with our hypothesis, individuals scoring higher in Honesty–Humility requested CMR less frequently. We also documented that individuals higher in Extraversion and lower in Conscientiousness requested CMR more frequently. We address limitations of the research and future research directions, including tests of the hypothesis that CMR involves duplicitous behaviors that are less typical of individual mate retention.

Non-human males attend to the presence of potential sexual rivals in the local environment to assess sperm competition risk, and adjust accordingly the deployment of sperm competition tactics (e.g., performing semen-displacing copulatory behaviors). We extend this research to humans using data from 45 married couples who completed questionnaires in a laboratory. We found that husbands whose wife spent more time with her male coworkers and male friends (i.e., potential sexual rivals) performed more semen-displacing copulatory behaviors at the couple's most recent copulation. We also found that performance of semen-displacing copulatory behaviors correlated with a novel cue to sperm competition risk: the discrepancy between the husband's sexual interest in his wife and her sexual interest in him. We also tested and refuted an alternative hypothesis that men adjust their copulatory thrusting to facilitate their partner's orgasm. Discussion highlights the novel contributions of the current research and notes limitations that can be addressed by future research.

Mate retention behaviors are designed to reduce the likelihood of partner infidelity and relationship withdrawal. We investigated the psychometric properties of the Persian translation of The Coalitional Mate Retention Inventory (CMRI) in Iran and explored the sex differences in the performance frequencies of these behaviors. Participants in a committed heterosexual romantic relationship ( n = 508, 270 female and 238 male) were drawn from a community sample. Participants reported demographic information (including age, duration of relationship), the Persian translation of CMRI, and the Persian translation of the Mate Retention Inventory–Short Form. The results of the confirmatory factor analyses demonstrated a good fit of the CMRI seven-factor model and achieved good reliability for CMRI and its subscales. We further documented sex differences in the frequency with which coalitional mate retention behaviors were performed. The results revealed that CMRI is a valuable instrument for assessing mate retention across diverse cultures.

Humans perform copulatory behaviors that do not contribute directly to reproduction (e.g., cunnilingus, prolonged copulation). We conducted a content analysis of pornography to investigate whether such behaviors might contribute indirectly to reproduction by influencing ejaculate volume—an indicator of ejaculate quality. We coded 100 professional pornography scenes depicting the same male actor copulating with 100 different females, affording control for between-male differences in estimated ejaculate volume. Coders visually estimated ejaculate volume and recorded the time the actor spent engaged in cunnilingus, penile-vaginal penetration, and in any physical contact with his partner. We found support for the hypothesis that a man who spends more time performing cunnilingus produces an ejaculate with greater estimated volume, even after controlling statistically for the age and attractiveness of the actress, and time spent in physical contact with his partner. Additionally, we tested the ejaculate adjustment hypothesis for prolonged copulation and found no support. Prolonged copulation does not facilitate production of an ejaculate with greater estimated volume, even after controlling statistically for time spent in physical contact with a partner. This research is the first to use content analysis to document that pre-ejaculatory copulatory behavior predicts estimated ejaculate volume and also is the first to document a relationship between the time spent performing cunnilingus and ejaculate quality.

A given man's phenotype embodies cues of his ancestral ability to effectively defend himself and his kin from harm, to survive adverse conditions, and to acquire status and mating opportunities. In this review, we explore the hypothesis that a man's phenotype also embodies cues to fertility or the probability that an ejaculate will fertilize ova. Female mate choice depends on the ability to discern the quality of a male reproductive partner through his phenotype, and male fertility may be among the traits that females have evolved to detect. A female who selects as mates males that deliver higher quality ejaculates will, on average, be more fecund than her competitors. Data on several non-human species demonstrate correlations between ejaculate quality and secondary sexual characteristics that inform female mate choice, suggesting that females may select mates in part on the basis of fertility. While the non-human literature on this topic has advanced, the human literature remains limited in scope and there is no clear consensus on appropriate methodologies or theoretical positions. We provide a comprehensive review and meta-analysis of this literature, and conclude by proposing solutions to the many issues that impede progress in the field. In the process, we hope to encourage interest and insight from investigators in other areas of human mating and reproductive biology. Am. J. Hum. Biol. 28:318-329, 2016. © 2015 Wiley Periodicals, Inc.

Intra- and intergroup conflict are likely to have been recurrent features of human evolutionary history; however, little research has investigated the factors that affect men’s combat alliance decisions. The current study investigated whether features of previous one-on-one combat with an opponent affect men’s interest in allying with that opponent for future group combat. Fifty-eight undergraduate men recruited from a psychology department subject pool participated in a one-on-one laboratory fight simulation. We manipulated fight outcome (between-subjects), perceived fighter health asymmetry (within-subjects), and the presence of a witness (within-subjects) over six sets of five rounds of fighting. Following each set, we asked men how interested they would be in allying with their opponent for future group combat. We found that men were more interested in allying with their opponent for future group combat if their opponent won the fight or if a witness was present, but perceived fighter-health asymmetry did not affect men’s decision to ally with their opponent. Exploratory analyses revealed a two-way interaction between fight outcome and the presence of a witness, such that winners without a witness present expressed less interest in allying with their opponent for future group combat. Our findings suggest that men attend to the benefits of allying with a man who has demonstrated relatively superior fighting ability. Alliance with a previous opponent for group combat may vary with the relationship value of the opponent and the utility of demonstrating cooperativeness to third-party observers. These findings inform our understanding of coalition formation.

Sperm competition occurs when a female copulates with two or more males within a sufficiently brief time period, resulting in the sperm of the different males competing to fertilize ova. In this chapter, we present the evidence of sperm competition in humans. We review the literature indicating anatomical, psychological, and physiological adaptations to human sperm competition. These adaptations include traits that produce prudent sperm allocation, copulatory interest, forced in-pair copulation, sexual fantasy, female orgasm, and semen-displacing copulatory behavior. Given the evidence of apparently convergent adaptations to sperm competition in humans and nonhumans, we conclude that sperm competition has been a important selection pressure that shaped human nature. Keywords: sperm competition; humans; evolutionary psychology; comparative psychology

Women perform oral sex on their male partner (i.e., fellatio) as part of a Benefit-Provisioning mate retention strategy, and women’s personality predicts their interest in, and time spent, performing fellatio. We explored whether women’s mate retention behavior mediates the relationship between their personality traits and their performance of fellatio in a long-term romantic relationship. Women (n = 401) reported their personality traits, the frequency with which they performed mate retention behaviors during the past month, and their interest in and the time they spent performing fellatio on their partner during their most recent sexual encounter. The results indicate that women higher in Conscientiousness spend more time performing fellatio on their partner, and this relationship is mediated by their Benefit-Provisioning mate retention. Women higher in Agreeableness report greater interest in performing fellatio on their partner, and less Cost-Inflicting mate retention, but mate retention behaviors do not mediate the relationship between their Agreeableness and their interest in performing fellatio. The current research is the first to investigate the relationship between women’s personality traits and oral sex behaviors, and contributes to research documenting that mate retention strategies are associated with sexual behavior.

Humans deploy various strategies to solve adaptive problems associated with a long-term partner’s infidelity. We investigated the relationships among three such strategies: individual mate retention, coalitional mate retention (i.e., mate retention with assistance from allies), and in-pair copulation frequency. Participants (n = 387; 176 women) in a committed, heterosexual relationship reported how often they (1) perform individual mate retention, (2) request coalitional mate retention, and (3) had sexual intercourse with their partner. The results indicate that women’s individual mate retention and men’s coalitional mate retention are positively associated with in-pair copulation frequency. The discussion notes limitations of this research and highlights the diversity of strategies humans deploy to address the adaptive problems of partner infidelity.

Friendship solved adaptive problems over human evolutionary history, including cooperative hunting and alloparenting. Pham, Barbaro, and Shackelford (in press) investigated another potential function of friendship: the provision of coalitional mate retention, whereby individuals ask an ally to assist with thwarting their romantic partner’s infidelity. In the current research, 387 participants (176 women) reported how often they requested or received coalitional mate retention from a male friend and from a female friend and reported on the quality of each friendship. The results indicate that the deployment of coalitional mate retention is positively associated with the quality of friendships with women (female–female friendships, male–female friendships, female–male friendships), but negatively associated with the quality of male–male friendships.

Women’s copulatory orgasm may function to retain sperm from men with “good genes”, one indicator of which is attractiveness, and one benefit of which is pathogen resistance. Women who perceive their partner to be more (vs. less) attractive are more likely to report orgasm at last copulation. Another benefit of male attractiveness to women is that he may sire offspring that will gain the heritable share of this advantage (i.e., “sexy sons”). Research has not addressed the “Sexy Sons” Hypothesis (e.g., as indicated by women’s perception of other women’s assessments of their partner’s attractiveness) in regards to female copulatory orgasm. We secured self-reports from 439 women in a committed, heterosexual relationship and investigated the relationships between women’s orgasm at last copulation and (1) women’s assessments of their partner’s attractiveness and (2) women’s perceptions of other women’s assessments of their partner’s attractiveness. The results indicate that women mated to more (vs. less) attractive men are more likely to report orgasm at last copulation, and this relationship is mediated by women’s perceptions of other women’s assessments of their partner’s attractiveness. We discuss the mediated relationship, note limitations of the research, and suggest future research directions.

Men who report performing more mate retention behaviors, in general, and more benefit-provisioning mate retention behaviors, in particular, also report greater interest in, and spend more time, performing oral sex on their female partner. We extended these findings to a female sample to investigate whether women’s oral sex behaviors are related to their mate retention behaviors. We secured self-report data from 410 women residing in the United States or in Germany in a committed, sexual, heterosexual relationship. The results indicate that women who report performing more benefit-provisioning mate retention behaviors also report greater interest in, and spend more time, performing oral sex on their partner. Further, there are no sex differences in the magnitudes or directions of these relationships. The results suggest that both men and women are more interested in, and spend more time, performing oral sex on their partner as part of a benefit-provisioning strategy to increase their partner’s relationship satisfaction. We address limitations of this research, and discuss explanations for the results.

Physical strength correlates with facial and body morphology, body movement, and sexual behavior, especially in men. Thus, physical strength may signal male quality in the context of intersexual and intrasexual selection. We investigated relationships of handgrip strength (a measure of upper body muscularity) and personality (as assessed via the “Big Five” factors) in a sample of British men (n = 75) and women (n = 86), aged 18 to 42 years. Handgrip strength correlated negatively with neuroticism and positively with extraversion in men, and negatively with agreeableness in women. The relationship of handgrip strength and neuroticism in men remained after controlling for the influence of age and body mass index. We conclude that handgrip strength provides information about male neuroticism. We discuss our findings with reference to recent reports on male quality correlates of strength.

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.

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.

Recent research on women’s ratings of men’s dance movements indicates that women derive similar cues of male “quality” (e.g., physical strength) from movement as from faces and bodies. Whether this extends to personality assessment is yet unclear. We recorded dance movements of 80 men using 3D optical motion-capture technology and secured self-reports of men’s personality standings. Dance movements were applied to a uniform, shape-standardized virtual humanoid character (avatar) and presented to women as 15-s videos for attractiveness and personality ratings. Women’s ratings of dance attractiveness correlated negatively with men’s self-reports and women’s ratings of men’s neuroticism and were positively correlated with men’s self-reported extraversion and women’s ratings of men’s conscientiousness. Men’s self-reported personality scores did not correlate with women’s ratings of men’s personality standings. Findings are discussed with reference to previous research and the social significance of dance movement cues and impression formation.

Expressed mate preferences provide unique windows into evolved mating psychology. The current study used two research instruments—one ranking and one rating procedure—to examine mate preferences in India. We compared modern Indians ( n = 536) with a more modest Indian sample studied a quarter of a century earlier ( n = 105) to test the hypothesis that sex-specific mate preferences—as hypothesized by parental investment theory—would persist during this time period. Mate preferences for mutual attraction and love remained important and invariant over time, despite India’s history of arranged marriages. Sex differences in mate preferences for cues to fertility (youth, physical attractiveness) and resources (good financial prospects, social status) remained relatively invariant over time. Several changes in mate preferences emerged, including a greater preference for mates who are “creative and artistic,” “ambitious and industrious,” and “a good cook and housekeeper” for both sexes. Despite cultural changes in India over the past 25 years, evolved mate preferences have persisted during this time period. Discussion highlights limitations of this research.

Conspecific violence has been pervasive throughout evolutionary history. The current research tested the hypotheses that individuals implicitly categorize combative contexts (i.e., play fighting, status contests, warfare, and anti-exploitative violence) and use the associated contextual information to guide expectations of combative tactics. Using U.S. and non-U.S. samples, Study 1 demonstrated consistent classification of combative contexts from scenarios for which little information was given and predictable shifts in the acceptability of combative tactics across contexts. Whereas severe tactics (e.g., eye-gouging) were acceptable in warfare and anti-exploitative violence, they were unacceptable in status contests and play fights. These results suggest the existence of implicit rules governing the contexts of combat. In Study 2, we explored the reputational consequences of violating these implicit rules. Results suggest that rule violators (e.g., those who use severe tactics in a status contest) are given less respect. These are the first studies to implicate specialized mechanisms for aggression that use contextual cues of violence to guide expectations and behavior.

Mate retention behaviors are designed to reduce the likelihood of partner infidelity and relationship termination. Measures of mate retention historically have focused on individual mate retention—behaviors that individuals perform alone. The current research explores coalitional mate retention (CMR)—mate retention with assistance from allies. Using an act nomination procedure, we constructed the CMR Inventory (CMRI) to assess specific CMR behaviors. In study 1, participants (n = 100) provided open-ended responses in which they nominated CMR behaviors. In study 2, participants (n = 387) provided frequency reports on the 44 CMR behaviors identified in study 1. We conducted principal component analyses to guide construction of the CMRI, which assesses seven components of CMRI: manipulation (e.g., “got my partner drunk to see what my partner said”), praise (e.g., “said nice things about me when my partner and other people were around”), vigilance (e.g., “observed how my partner acted around people interested in my partner”), monopolizing time (e.g., “accompanied my partner to a party”), therapy (e.g., “told my partner how much I liked my partner”), gifts (e.g., “told me what gifts my partner wanted”), and violence (e.g., “hit someone who was flirting with my partner”). Discussion highlights the limitations of focusing exclusively on individual mate retention and the importance of considering alliances when researching mate retention.

Men perform oral sex on their romantic partner as part of a broader benefit-provisioning mate retention strategy and men higher in Agreeableness are especially likely to provision their partner with benefits. The current research explored whether men's benefit-provisioning mate retention behavior mediated the relationship between their Agreeableness and their oral sex behaviors in their long-term romantic relationship. Men (n = 346) in a committed, sexual, heterosexual relationship completed the Mate Retention Inventory-a 104-item instrument that assesses the frequency with which they performed various mate retention behaviors during the past month, a 40-item personality inventory, and reported on a questionnaire their interest in and the time they spent performing oral sex on their romantic partner during their most recent sexual encounter with her. The results indicated that men higher in Agreeableness reported greater interest in and spent more time performing oral sex on their partner, and that their benefit-provisioning mate retention behaviors partially mediated these relationships. The current research is the first to investigate the relationship between personality dimensions and oral sex behaviors and adds to a growing body of research documenting that mate retention strategies influence sexual behavior.

Sperm competition occurs when a female copulates with two or more males within a sufficiently brief time period, resulting in sperm of the different males competing to fertilize ova. Sperm competition has been documented or inferred to occur across several species. We address the evidence for sperm competition in humans by reviewing literature indicating apparently convergent adaptations to sperm competition in humans and non-humans. We discuss future research directions, and conclude that the evidence for anatomical, biological, physiological, and behavioral adaptations to human sperm competition provides compelling evidence that sperm competition has been a recurrent feature of human evolutionary history.

Nonhuman males attend to the number of potential sexual rivals in the local environment to assess sperm competition risk. Males of these species sometimes perform more frequent in-pair copulations to increase the likelihood of success in sperm competition. Here, we extend this research to humans, Homo sapiens. We secured self-report data from 393 men in a committed, sexual, heterosexual relationship. The results indicate that men whose in-pair partner has more male coworkers and friends (i.e., potential sexual rivals) also perform more frequent in-pair copulations, but only among men who perceive their partner to be particularly attractive relative to assessments of partners by other men in the sample. This research is the first to empirically investigate the number of potential male rivals in the local environment as a cue to sperm competition risk in humans. Discussion addresses limitations of the current research and highlights directions for future research.

Personality features are associated with several relationship outcomes. We examined whether specific personality features differed in their associations with ''mate retention'' strategies. We examined the unique associations that personality features had with mate retention strategies reported by 179 community members in romantic relationships for at least 6 months. Personality features were associated with each of the mate retention strategies such that positive personality features (e.g., high levels of honesty-humility) were associated with less reliance on mate retention strategies that involved manipulating, deceiving, or exploiting romantic partners. Discussion focuses on the implications of these results for understanding the connection between personality features and behaviors intended to preserve and maintain romantic relationships.

Objectives Physical strength provides information about male quality and can be assessed from facial and body morphology. Research on perception of dance movements indicates that body movement also provides information about male physical strength. These relationships have not been investigated for women. Methods We investigated relationships of handgrip strength (HGS) and dance attractiveness perception in 75 men and 84 women. Results We identified positive relationships between HGS and opposite-sex assessments of dance attractiveness for men but not women. Conclusions The replication of previous research investigating relationships between dance attractiveness and physical strength in men corroborates the hypothesis that dance movements provide information about male quality. We argue that these relationships are interpretable in contexts of inter- and intra-sexual selection. Am. J. Hum. Biol. 27:728–730, 2015. © 2015 Wiley Periodicals, Inc.

Men perform “mate retention” behaviors to reduce the likelihood of their partner’s infidelity. One mate retention strategy men use is to increase their partner’s relationship satisfaction by provisioning her with benefits. We recruited 351 men to investigate whether men perform oral sex on their partner as part of a broader benefit-provisioning mate retention strategy. In support of the predictions, men who reported performing more mate retention behaviors, in general, and more benefit-provisioning mate retention behaviors, in particular, also reported greater interest in and spent more time performing oral sex on their partner. We present limitations of the research and discuss the benefits of an evolutionary perspective for investigating oral sex as a mate retention behavior.

An evolutionary history of human female infidelity and consequent sperm competition may have caused the evolution of male counter-adaptations. The infidelity-detection hypothesis for oral sex proposes that men perform oral sex to gather information about their partner’s recent sexual history. We tested this hypothesis with data secured from 231 men in committed, sexual, heterosexual relationships. We found support for two derivative predictions: men at a greater recurrent risk of sperm competition expressed greater interest in, and spent more time performing, oral sex on their partner, even after controlling statistically for relationship length, relationship satisfaction, and sexual intercourse duration. The discussion addresses limitations of this research and highlights directions for future research, including distinguishing empirically the infidelity-detection hypothesis from alternative hypotheses for oral sex.

Sperm competition theory has been used to generate the hypothesis that men prefer to view pornographic images suggesting the presence of a rival male, over images which do not. The current research uses a new methodology to address conflicting evidence about men’s preferences for pornographic images. Raters coded a random sample of 166 pornographic DVDs (from a population of 49 493), which were then analyzed using multiple regression. Consistent with the hypothesis generated from sperm competition theory, the number of images on a DVD cover and screenshots depicting 2 or more men interacting with 1 woman (suggesting the presence of sperm competition) predicts DVD sales rank, whereas the number of images on a DVD cover and screenshots depicting 2 or more women interacting with 1 man (suggesting the absence of sperm competition) does not predict DVD sales rank. Discussion addresses limitations and future directions, including using penile plethysmography to avoid relying on correlational analyses.

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.

HIV-1 replication is concentrated within CD4+ T cells in B cell follicles of secondary lymphoid tissues during asymptomatic disease. Limited data suggest that a subset of T follicular helper cells (TFH) within germinal centers (GC) is highly permissive to HIV-1. Whether GC TFH are the major HIV-1 virus–producing cells in vivo has not been established. In this study, we investigated TFH permissivity to HIV-1 ex vivo by spinoculating and culturing tonsil cells with HIV-1 GFP reporter viruses. Using flow cytometry, higher percentages of GC TFH (CXCR5highPD-1high) and CXCR5+programmed cell death-1 (PD-1)low cells were GFP+ than non-GC TFH (CXCR5+PD-1intermediate) or extrafollicular (EF) (CXCR5−) cells. When sorted prior to spinoculation, however, GC TFH were substantially more permissive than CXCR5+PD-1low or EF cells, suggesting that many GC TFH transition to a CXCR5+PD-1low phenotype during productive infection. In situ hybridization on inguinal lymph node sections from untreated HIV-1–infected individuals without AIDS revealed higher frequencies of HIV-1 RNA+ cells in GC than non-GC regions of follicle or EF regions. Superinfection of HIV-1–infected individuals’ lymph node cells with GFP reporter virus confirmed the permissivity of follicular cells ex vivo. Lymph node immunostaining revealed 96% of CXCR5+CD4+ cells were located in follicles. Within sorted lymph node cells from four HIV-infected individuals, CXCR5+ subsets harbored 11–66-fold more HIV-1 RNA than CXCR5− subsets, as determined by RT PCR. Thus, GC TFH are highly permissive to HIV-1, but downregulate PD-1 and, to a lesser extent, CXCR5 during HIV-1 replication. These data further implicate GC TFH as the major HIV-1–producing cells in chronic asymptomatic HIV-1 infection.

A given man's phenotype embodies cues of his ancestral ability to effectively defend himself and his kin from harm, to survive adverse conditions, and to acquire status and mating opportunities. In this review, we explore the hypothesis that a man's phenotype also embodies cues to fertility or the probability that an ejaculate will fertilize ova. Female mate choice depends on the ability to discern the quality of a male reproductive partner through his phenotype, and male fertility may be among the traits that females have evolved to detect. A female who selects as mates males that deliver higher quality ejaculates will, on average, be more fecund than her competitors. Data on several non-human species demonstrate correlations between ejaculate quality and secondary sexual characteristics that inform female mate choice, suggesting that females may select mates in part on the basis of fertility. While the non-human literature on this topic has advanced, the human literature remains limited in scope and there is no clear consensus on appropriate methodologies or theoretical positions. We provide a comprehensive review and meta-analysis of this literature, and conclude by proposing solutions to the many issues that impede progress in the field. In the process, we hope to encourage interest and insight from investigators in other areas of human mating and reproductive biology. Am. J. Hum. Biol. 28:318-329, 2016. © 2015 Wiley Periodicals, Inc.

Previous studies on sex-differentiated mate preferences have focused on univariate analyses. However, because mate selection is inherently multidimensional, a multivariate analysis more appropriately measures sex differences in mate preferences. We used the Mahalanobis distance ( D) and logistic regression to investigate sex differences in mate preferences with data secured from participants residing in 37 cultures ( n = 10,153). Sex differences are large in multivariate terms, yielding an overall D = 2.41, corresponding to overlap between the sexes of just 22.8%. Moreover, knowledge of mate preferences alone affords correct classification of sex with 92.2% accuracy. Finally, pattern-wise sex differences are negatively correlated with gender equality across cultures but are nonetheless cross-culturally robust. Discussion focuses on implications in evaluating the importance and magnitude of sex differences in mate preferences.

Stewart-Williams and Thomas (this issue) present a well-written but misguided argument detailing their concerns regarding exaggerated sex differences in the evolutionary psychological literature. I...

Sperm competition occurs when a female copulates with two or more males within a sufficiently brief time period, resulting in sperm of the different males competing to fertilize ova. Sperm competition has been documented or inferred to occur across several species. We review the evidence for sperm competition in humans. Specifically, we review literature indicating apparently convergent adaptations to sperm competition in humans and nonhumans. We discuss future research directions and conclude that the research that documents anatomical, biological, physiological, and behavioral adaptations to human sperm competition provides compelling evidence that sperm competition has been a recurrent feature of human evolutionary history.