Sexes
Revisiting the Income Tax Effects of Legalizing Same-Sex Marriages
James Alm, Sebastian Leguizamon & Susane Leguizamon
Journal of Policy Analysis and Management, forthcoming
Abstract:
In this paper we estimate the impacts on income tax collections of legalizing same-sex marriage. We utilize new individual-level data sources to estimate the federal income tax consequences of legalizing same-sex marriages. These data sources also allow us to estimate the impact of legalization on state income tax collections. We find that 23 states would realize a net fiscal benefit from legalization, while 21 states would experience a decline in revenue. The potential (annual) changes in state tax revenue range from negative $29 million in California to positive $16 million in New York. At the federal level, our estimates suggest an overall reduction in revenues, ranging from a potential loss of $187 million to $580 million. Overall, we find that the federal and state impacts are quite modest. We also find that our estimates are only marginally affected by alternative assumptions about how many same-sex couples will choose to marry and which partner will claim any children for tax deduction purposes.
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Ian Ayres & Richard Luedeman
Yale Law Journal, December 2013, Pages 714-768
Abstract:
This Essay reports the results of a survey experiment that we conducted on over eight hundred heterosexual respondents to compare associational attitudes toward gay men who engage in different types of sexual practices. Specifically, we randomly assigned respondents to hear one of three descriptions of a gay character, which differed only with regard to the character’s penetrative preference: top (preferring to penetrate one’s partner), bottom (preferring to be penetrated by one’s partner), and versatile (having an equal preference). Overall, we find that heterosexuals displayed heightened and statistically significant associational aversion toward versatile characters and, to a lesser degree, toward bottom characters, relative to respondents’ willingness to associate with top characters. We elaborate why heterosexuals seem to display systematically less associational aversion toward those men whose penetrative preference is most consistent with gender stereotypes. Based on those results, we revisit the notion, adopted by many courts, that Price Waterhouse sex-stereotyping doctrine cannot apply to sexuality claims because it would turn sexual orientation into a protected class after Congress has opted not to do so. Our results suggest that gender-motivated homophobia is not uniformly targeted toward all gay men or uniformly present among all who discriminate on the basis of sexual orientation. We also further consider why respondents were most averse to versatility, drawing a potential distinction between “trait opposition” and “trait intermediacy” gender violations. Finally, we discuss the implications of our findings for the broader LGBT movement in law and society.
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Anthony Lee et al.
Psychological Science, forthcoming
Abstract:
For women, choosing a facially masculine man as a mate is thought to confer genetic benefits to offspring. Crucial assumptions of this hypothesis have not been adequately tested. It has been assumed that variation in facial masculinity is due to genetic variation and that genetic factors that increase male facial masculinity do not increase facial masculinity in female relatives. We objectively quantified the facial masculinity in photos of identical (n = 411) and nonidentical (n = 782) twins and their siblings (n = 106). Using biometrical modeling, we found that much of the variation in male and female facial masculinity is genetic. However, we also found that masculinity of male faces is unrelated to their attractiveness and that facially masculine men tend to have facially masculine, less-attractive sisters. These findings challenge the idea that facially masculine men provide net genetic benefits to offspring and call into question this popular theoretical framework.
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Gender Differences in Risk Aversion: Do Single-Sex Environments Affect their Development?
Alison Booth, Lina Cardona-Sosa & Patrick Nolen
Journal of Economic Behavior & Organization, forthcoming
Abstract:
Single-sex classes within coeducational environments are likely to modify students’ risk-taking attitudes in economically important ways. To test this, we designed a controlled experiment using first year college students who made choices over real-stakes lotteries at two distinct dates. Students were randomly assigned to weekly classes of three types: all female, all male, and coeducational. They were not allowed to change group subsequently. We found that women are less likely to make risky choices than men at both dates. However, after eight weeks in a single-sex class environment, women were significantly more likely to choose the lottery than their counterparts in coeducational groups. These results are robust to the inclusion of controls for IQ and for personality type, as well as to a number of sensitivity tests. Our findings suggest that observed gender differences in behaviour under uncertainty found in previous studies might partly reflect social learning rather than inherent gender traits.
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Exposure to prenatal life events stress is associated with masculinized play behavior in girls
Emily Barrett et al.
NeuroToxicology, forthcoming
Abstract:
Previous research has shown that prenatal exposure to endocrine-disrupting chemicals can alter children's neurodevelopment, including sex-typed behavior, and that it can do so in different ways in males and females. Non-chemical exposures, including psychosocial stress, may disrupt the prenatal hormonal milieu as well. To date, only one published study has prospectively examined the relationship between exposure to prenatal stress and gender-specific play behavior during childhood, finding masculinized play behavior in girls who experienced high prenatal life events stress, but no associations in boys. Here we examine this question in a second prospective cohort from the Study for Future Families. Pregnant women completed questionnaires on stressful life events during pregnancy, and those who reported one or more events were considered “stressed”. Families were recontacted several years later (mean age of index child: 4.9 years), and mothers completed a questionnaire including the validated Preschool Activities Inventory (PSAI), which measures sexually dimorphic play behavior. In sex-stratified analyses, after adjusting for child's age, parental attitudes towards gender-atypical play, age and sex of siblings, and other relevant covariates, girls (n = 72) exposed to prenatal life events stress had higher scores on the PSAI masculine sub-scale (β=3.48, p = 0.006) and showed a trend towards higher (more masculine) composite scores (β=2.63, p = 0.08). By contrast, in males (n = 74), there was a trend towards an association between prenatal stress and higher PSAI feminine sub-scale scores (β=2.23, p = 0.10), but no association with masculine or composite scores. These data confirm previous findings in humans and animal models suggesting that prenatal stress is a non-chemical endocrine disruptor that may have androgenic effects on female fetuses and anti-androgenic effects on male fetuses.
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Moral elevation reduces prejudice against gay men
Calvin Lai, Jonathan Haidt & Brian Nosek
Cognition & Emotion, forthcoming
Abstract:
Disgust is linked to social evaluation. People with higher disgust sensitivity exhibit more sexual prejudice, and inducing disgust increases sexual prejudice. We tested whether inducing moral elevation, the theoretical opposite of disgust, would reduce sexual prejudice. In four studies (N = 3622), we induced elevation with inspiring videos and then measured sexual prejudice with implicit and explicit measures. Compared to control videos that elicited no particular affective state, we found that elevation reduced implicit and explicit sexual prejudice, albeit very slightly. No effect was observed when the target of social evaluation was changed to race (Black–White). Inducing amusement, another positive emotion, did not significantly affect sexual prejudice. We conclude that elevation weakly but reliably reduces prejudice towards gay men.
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Boys will be boys: Sex differences in wild infant chimpanzee social interactions
Elizabeth Lonsdorf et al.
Animal Behaviour, February 2014, Pages 79–83
Abstract:
Sex differences in the behaviour of human children are a hotly debated and often controversial topic. However, several recent studies have documented a biological basis to key aspects of child social behaviour. To further explore the evolutionary basis of such differences, we investigated sex differences in sociability in wild chimpanzee, Pan troglodytes schweinfurthii, infants at Gombe National Park, Tanzania. We used a long-term data set on mother–infant behaviour to analyse the diversity of infant chimpanzee social partners from age 30 to 36 months. Male infants (N = 12) interacted with significantly more individuals than female infants did (N = 8), even when maternal sociability was controlled for. Furthermore, male infants interacted with significantly more adult males than female infants did. Our data indicate that the well-documented sex differences in adult chimpanzee social tendencies begin to appear quite early in development. Furthermore, these data suggest that the behavioural sex differences of human children are fundamentally rooted in our biological and evolutionary heritage.
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Sex differences in the structural connectome of the human brain
Madhura Ingalhalikar et al.
Proceedings of the National Academy of Sciences, forthcoming
Abstract:
Sex differences in human behavior show adaptive complementarity: Males have better motor and spatial abilities, whereas females have superior memory and social cognition skills. Studies also show sex differences in human brains but do not explain this complementarity. In this work, we modeled the structural connectome using diffusion tensor imaging in a sample of 949 youths (aged 8–22 y, 428 males and 521 females) and discovered unique sex differences in brain connectivity during the course of development. Connection-wise statistical analysis, as well as analysis of regional and global network measures, presented a comprehensive description of network characteristics. In all supratentorial regions, males had greater within-hemispheric connectivity, as well as enhanced modularity and transitivity, whereas between-hemispheric connectivity and cross-module participation predominated in females. However, this effect was reversed in the cerebellar connections. Analysis of these changes developmentally demonstrated differences in trajectory between males and females mainly in adolescence and in adulthood. Overall, the results suggest that male brains are structured to facilitate connectivity between perception and coordinated action, whereas female brains are designed to facilitate communication between analytical and intuitive processing modes.
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No Evidence of Sexual Risk Compensation in the iPrEx Trial of Daily Oral HIV Preexposure Prophylaxis
Julia Marcus et al.
PLoS ONE, December 2013
Objective: Preexposure prophylaxis (PrEP) with emtricitabine/tenofovir disoproxil fumarate (FTC/TDF) reduced HIV acquisition in the iPrEx trial among men who have sex with men and transgender women. Self-reported sexual risk behavior decreased overall, but may be affected by reporting bias. We evaluated potential risk compensation using biomarkers of sexual risk behavior.
Design and methods: Sexual practices were assessed at baseline and quarterly thereafter; perceived treatment assignment and PrEP efficacy beliefs were assessed at 12 weeks. Among participants with ≥1 follow-up behavioral assessment, sexual behavior, syphilis, and HIV infection were compared by perceived treatment assignment, actual treatment assignment, and perceived PrEP efficacy.
Results: Overall, acute HIV infection and syphilis decreased during follow-up. Compared with participants believing they were receiving placebo, participants believing they were receiving FTC/TDF reported more receptive anal intercourse partners prior to initiating drug (12.8 vs. 7.7, P = 0.04). Belief in receiving FTC/TDF was not associated with an increase in receptive anal intercourse with no condom (ncRAI) from baseline through follow-up (risk ratio [RR] 0.9, 95% confidence interval [CI]: 0.6–1.4; P = 0.75), nor with a decrease after stopping study drug (RR 0.8, 95% CI: 0.5–1.3; P = 0.46). In the placebo arm, there were trends toward lower HIV incidence among participants believing they were receiving FTC/TDF (incidence rate ratio [IRR] 0.8, 95% CI: 0.4–1.8; P = 0.26) and also believing it was highly effective (IRR 0.5, 95% CI: 0.1–1.7; P = 0.12).
Conclusions: There was no evidence of sexual risk compensation in iPrEx. Participants believing they were receiving FTC/TDF had more partners prior to initiating drug, suggesting that risk behavior was not a consequence of PrEP use.
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Stereotyping to Infer Group Membership Creates Plausible Deniability for Prejudice-Based Aggression
William Cox & Patricia Devine
Psychological Science, forthcoming
Abstract:
In the present study, participants administered painful electric shocks to an unseen male opponent who was either explicitly labeled as gay or stereotypically implied to be gay. Identifying the opponent with a gay-stereotypic attribute produced a situation in which the target’s group status was privately inferred but plausibly deniable to others. To test the plausible deniability hypothesis, we examined aggression levels as a function of internal (personal) and external (social) motivation to respond without prejudice. Whether plausible deniability was present or absent, participants high in internal motivation aggressed at low levels, and participants low in both internal and external motivation aggressed at high levels. The behavior of participants low in internal and high in external motivation, however, depended on experimental condition. They aggressed at low levels when observers could plausibly attribute their behavior to prejudice and aggressed at high levels when the situation granted plausible deniability. This work has implications for both obstacles to and potential avenues for prejudice-reduction efforts.
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Successful hunting increases testosterone and cortisol in a subsistence population
Benjamin Trumble et al.
Proceedings of the Royal Society: Biological Sciences, 7 February 2014
Abstract:
Controversy over the adaptive significance of male hunting in subsistence societies hinges on the relative importance of familial provisioning and mate-quality signalling. This paper examines the proximate and ultimate motivations of hunting behaviour from a neuroendocrine perspective, using salivary testosterone and cortisol data collected before, during and after hunting focal follows from 31 Tsimane hunters aged 18–82 years. Despite circadian declines in hormone levels, testosterone and cortisol of Tsimane hunters increased at the time of a kill, and remained high as successful hunters returned home. Previous studies of hormonal changes during competitions find that high-stakes and success in the presence of relevant audiences result in increased neuroendocrine arousal. If men hunt primarily to provision their families, then an additional audience would not be expected to impact testosterone or cortisol, nor would the size of the animal killed. However, if signalling male quality by ‘showing off’ was a larger relative driver of men's hunting behaviour, one would expect greater hormonal response in cases where men returned with large sharable kills, especially in the presence of community members. Consistent with provisioning models of male hunting motivation, neither kill size nor encountering an audience of villagers while returning from hunting was associated with hormonal changes for successful hunters.
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Stacia Brantley-Hill & Thomas Brinthaupt
Journal of Homosexuality, February 2014, Pages 270-287
Abstract:
People are sometimes hesitant to communicate affection if it might be misinterpreted by the intended receiver or an audience. We hypothesized that anti-gay/-lesbian attitudes might negatively affect the perceived appropriateness of expressing affection. One hundred and twenty male and female undergraduates with either very high or very low levels of anti-gay/-lesbian attitudes participated in the study. They rated the appropriateness of expressing affection toward same- and other-sex targets in a set of 2 (public or private setting) × 3 (positive, neutral, or negative valence) scenarios. Results supported a “generalized inhibition” effect, with high levels of anti-gay/-lesbian attitudes associated with a reluctance to express affection regardless of target, setting, valence, or current relationship status. Implications for research on affectionate expression and anti-gay/-lesbian attitudes are presented.
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Estradiol and Mental Rotation: Relation to Dimensionality, Difficulty, or Angular Disparity?
Elizabeth Hampson, Na'ama Levy-Cooperman & Jennifer Korman
Hormones and Behavior, forthcoming
Abstract:
Several studies have reported that performance on spatial rotation tests is better at menses than at high estradiol phases of the menstrual cycle in women. These effects are debated because nearly all reports of menstrual cycle variability have relied on a single test, the Mental Rotations Test (MRT, Vandenberg & Kuse, 1978). In the present study, we investigated key features of the MRT that might be responsible for its association with estradiol levels. We hypothesized that associations could be demonstrated for other tasks that share the same characteristics. Forty-four women ages 20–38 yr, matched on education and general ability, were assessed at low (n = 24) or high (n = 20) estradiol stages of the menstrual cycle on a set of spatial tests that varied in dimensionality, plane of rotation, angular disparity, and effortfulness. Saliva was used to quantify estradiol and progesterone. Low estradiol was found to be associated with significantly better accuracy on the MRT and also on a mental rotation task that required large angles of rotation but employed only two-dimensional object representations and rotations limited to the picture plane. In contrast, a task using identical stimuli that required only small angles of rotation did not show an estradiol effect. A group difference also was seen on a test of perceptual closure. The results confirm that the estradiol effect is not limited to the MRT, and identify the rotational element, but also aspects of figural perception, as possible processes that may be responsive to estrogens. These findings advance our understanding by showing an association between estradiol and discrete spatial processes. Implications for understanding the origins of the robust sex difference commonly observed on the MRT are discussed.
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Radha Kothari et al.
American Journal of Human Biology, forthcoming
Objectives: Markers of prenatal hormone exposure have been associated with the development of eating disorder (ED) behaviors. Our aim was to determine whether 2D:4D ratio, a marker for in utero testosterone exposure, is associated with risk for ED in a large population-based cohort: the Avon Longitudinal Study of Parents and Children (ALSPAC).
Methods: This is the first study to investigate prenatal testosterone exposure in children at high-risk for ED, using 2D:4D as a marker. We compared children whose mothers reported a lifetime ED (anorexia, bulimia, or both; N = 446) to children whose mothers did not (n = 5,367).
Results: Daughters of women with lifetime bulimia nervosa (BN) had lower 2D:4D ratio (B: −0.01, 95% CI: −0.02 to −0.002, P = 0.02), indicating higher prenatal testosterone exposure, than daughters of mothers unaffected by ED. No differences were observed in the male children of women with an ED.
Conclusions: Findings suggest that children at high-risk for BN may be exposed to higher levels of testosterone in utero. Fetal exposure to androgen excess is thought to be causal in the development of polycystic ovary syndrome (PCOS), a disorder which is highly comorbid with binge eating and BN. Future research should investigate the potential role of testosterone exposure in utero as a risk factor for BN and binge eating.
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Sabra Katz-Wise et al.
Journal of Adolescent Health, forthcoming
Purpose: This research aimed to explain sexual orientation disparities in body mass index (BMI) by examining child abuse history, weight-related behaviors, and sociodemographics.
Methods: We used data from 7,960 females and 5,992 males from the prospective Growing Up Today Study over nine waves between 1996 (ages 12–14 years) and 2007 (ages 20–25 years). Using repeated measures of BMI (kg/m2) as a continuous outcome, gender-stratified latent quadratic growth models adjusted for child abuse history, weight-related behaviors, and sociodemographics. BMI at age 17 years (intercept) and 1-year change in BMI (slope) are reported.
Results: Bisexual females had higher BMI at age 17 years (β = 1.59, 95% CI = 1.00–2.18) and displayed greater one-year increases in BMI (β = .09, 95% CI = .03–.14), compared with completely heterosexual females. Gay males displayed smaller 1-year increases in BMI (β = −.19, 95% CI = −.25 to −.12), compared with completely heterosexual males. No sexual orientation differences in BMI at age 17 years were observed for males, but gay males' BMI at age 25 was less than completely heterosexual males' BMI by 2 units. Among females, sexual orientation differences remained but were slightly attenuated after controlling for child abuse history, weight-related behaviors, and sociodemographics. Among males, the addition of child abuse and weight-related behaviors did not change the estimated difference in 1-year BMI increases.
Conclusions: Sexual orientation differences in BMI were partly explained by child abuse and weight-related behaviors in females. More research is needed to explore additional drivers of these disparities among both females and males.