Rolf Degen summarizes... The male attraction to nubile traits in females may reflect an evolved strategy to safeguard a successful first pregnancy

Does Nubility Indicate More Than High Reproductive Value? Nubile Primiparas’ Pregnancy Outcomes in Evolutionary Perspective. William D. Lassek, Steven J. C. Gaulin. Evolutionary Psychology, September 15, 2021. https://doi.org/10.1177/14747049211039506

Abstract: The idea that human males are most strongly attracted to traits that peak in women in the nubile age group raises the question of how well women in that age group contend with the potential hazards of a first pregnancy. Using data for 1.7 million first births from 1990 U.S. natality and mortality records, we compared outcomes for women with first births (primiparas) aged 16–20 years (when first births typically occur in forager and subsistence groups) with those aged 21–25 years. The younger primiparas had a much lower risk of potentially life-threatening complications of labor and delivery and, when evolutionarily novel risk factors were controlled, fetuses which were significantly more likely to survive despite lower birth weights. Thus, nubile primiparas were more likely to have a successful reproductive outcome defined in an evolutionarily relevant way (an infant of normal birth weight and gestation, surviving to one year, and delivered without a medically necessary cesarean delivery). This suggests that prior to the widespread availability of surgical deliveries, men who mated with women in the nubile age group would have reaped the benefit of having a reproductive partner more likely to have a successful first pregnancy.

Keywords: first pregnancy, female attractiveness, nubility, primiparas, pregnancy complications, mating preferences, reproductive timing

Discussion

Nubile Mothers Have Better First-Pregnancy Outcomes

As noted in the Introduction section, recent evidence suggests that heterosexual men are attracted to attributes characteristic of physically and sexually mature women between 15 and 19 years of age, closely corresponding to the 16–20 years age group when first births typically occur in natural-fertility populations (Kramer & Lancaster, 2010; Lassek & Gaulin, 2019; Symons, 1979; Walker, 2019). Relevant to that preference, the current study is consistent with others in a variety of populations indicating that, when surgical deliveries are not available, this is also the age group with the best first-pregnancy outcomes.

In our large sample, primiparas were at much higher risk than multiparas for CPD, critical C-sections, and other complications of labor and delivery that increase the risk of maternal mortality, but primiparas aged 16–20 years had substantially lower risks than those 21–25, experiencing a 30% lower risk of any C-section, a 27% lower risk of a critical C-section, and much lower risks for serious complications of labor and delivery, including CPD, abnormal labor, and fetal distress (Table 4). These findings are consistent with many other studies that show a reduced risk of C-sections in primiparas aged 16–19 years versus older mothers, including studies in many non-Western countries (Conde-Agudelo et al., 2000; Ganchimeg et al., 2013, 2014).

The reduced risk of complications of labor and delivery in primiparas aged 16–20 years is of special importance in a species where the conjunction of bipedalism and very large brains has made vaginal births difficult. Only very recently have these conflicting selection pressures been relieved by the surgical innovation of C-section, an intervention still not available everywhere. Where and when such surgical births are unavailable, it is essential for a first-time mother to produce a child who can successfully pass through her birth canal so that mother and child can survive and continue to augment her fitness.

Our study does not present data on maternal survival, but the lower risk of labor-and-delivery complications for mothers in the nubile age group would likely decrease the risk of maternal deaths in childbirth. In a recent study of maternal mortality in 144 countries (Nove et al., 2014), in a third of countries mortality was lower for mothers aged 15–19 years than those aged 20–24 years; and this included most of the countries with the highest maternal mortality rates.

There may also be survival benefits for the infants of younger mothers. Our study is consistent with others showing comparable survival in the newborns of mothers aged 16–19 years with those aged 20–24 years when social and behavioral risk factors are controlled (Bradford & Giles, 1989; Conde-Agudelo et al., 2000; Gallais et al., 1996; Ganchimeg et al., 2013, 2014; Geist et al., 2006; Geronimus & Korenman, 1992; Phipps-Yonas, 1980; Scholl et al., 1984; Smith & Pell, 2001).

When evolutionarily novel risk factors were controlled, the fetuses and newborns of primiparas aged 16–20 years did as well or better as those of primiparas aged 21–25 years and were more likely to survive to 1 year. Although the 16–20-year old primiparas had significantly more preterm births with normal birth weights (which have good survival rates), their risks for preterm births with low birth weight, overall low birth weight, and neonatal mortality were significantly lower.

These results are also consistent with the finding that in 18th–19th century Germany, when infant and child mortality rates were much higher, the children of mothers aged 15–19 years were more likely to survive to reproductive age than those of older mothers (Knodel & Hermalin, 1984). Such high infant and child mortality rates were also likely in the environment of evolutionary adaptedness (EEA; Tooby and Cosmides, 1992), with almost half of children dying before reaching puberty (Volk & Atkinson, 2013).

Because until quite recently most women gave birth at home with assistance from their relatives, another potential advantage for younger mothers is their greater likelihood of having mothers, grandmothers, and aunts to help with pregnancy and childbirth, especially in groups with shorter life expectancies, where senior kin may have been less common.

Thus, it is not surprising that women's evolved life history seems to schedule first reproduction soon after the attainment of adult size and sexual maturity, as revealed by the demography of subsistence populations. Primiparas aged 16–20 years were likely to have a better newborn outcome than older primiparas and much better labor-and-delivery outcomes, which combine to yield a substantially greater chance for a successful pregnancy outcome (Figure 3).

Evolution of Male Preferences for Nubility

Because first pregnancies are most likely to be successful in women in the 16–20 years age group, we would expect positive selection on male preferences that targeted any reliable phenotypic correlates of this female life stage. Thus, this study, together with others showing the advantages of first births in this age range, when first births typically occur in subsistence populations, supports nubility as a key criterion of female attractiveness.

Men’s preferences for certain female traits associated with nubility—such as low WHRs, low BMIs (in well-nourished populations), and low waist–stature ratios (which may be the best predictor of attractiveness)—have recently been explained in terms of their correlation with female reproductive value (Andrews et al., 2017; Butovskaya et al., 2017; Fessler et al., 2005; Lassek & Gaulin, 2019; Marlowe, 1998; Prokop et al., 2020; Röder et al., 2013; Sugiyama, 2005; Symons, 1979, 1995), an inherently future-oriented parameter (Fisher, 1930). Complementing those findings, this study suggests an additional, more immediate, benefit to preferences for nubility.

If, as our findings suggest, nubile women have had more successful first-pregnancy outcomes than older women (thus enhancing their own reproductive success), men with preferences for traits correlated with nubility would have experienced a parallel fitness advantage. Conscious awareness would not have been required for this preference to evolve (Gaulin & McBurney, 2001; Kenrick, 1995); genetic variance in the preference and a reliable correlation between the preferred trait (e.g., any sign of nubility) and a positive fitness outcome (e.g., a successful first birth) would be sufficient.

The main cost to males who prefer nubile women is the lower frequency of ovulation in younger women (see Lassek and Gaulin, 2018a). However, this can be largely overcome by an increased frequency of coitus, which is usual for this age group (Weinstein et al., 1990). The fact that the typical age at first birth falls in the nubile period in traditional populations suggests that copulatory effort is normally sufficient to overcome the lower probability of conception with women in this age group.

Because of the lower fertility of nubile women, Symons (1979) suggested that males seeking short-term mating with minimal commitment might prefer older women who would have a greater chance of conceiving, as fertility is maximal in the late 20s. However, Symons (1995) changed his view because of studies in modern hunter-gatherers showing most potentially fertile women over 20 are either pregnant or nursing, with small windows of time when conception is possible. In this context, nubile women are likely to have a greater chance of conceiving despite their reduced frequency of ovulation.

Why do Nubile Primiparas Have Better Obstetric Outcomes?

Three factors help to explain the lower risk of critical surgical deliveries in the 16–20-year-old mothers: (a) Younger primiparas had smaller newborns than older primiparas, with more neonates weighing 2.5–3.4 kg, in the lower two-thirds of the normal range (2.5–3.9 kg), and fewer weighing 3.5 kg or more (Table 3). As shown in Figure 1, smaller neonates are less likely to have CPD or require a critical C-section. (b) For newborns of the same birth weight, nubile primiparas had a much lower risk of a critical C-section (Figure 1), and all but one of its associated complications, than those over 20. (c) The fetuses of younger primiparas were less likely to experience complications during labor and delivery, including fetal distress, cord prolapse, placenta previa, and abnormal position (Table 4). In total, younger mothers seem to have an enhanced ability to move their fetus through the birth canal and their fetuses also seem to be more tolerant of the stresses of labor and delivery.

Negative Consequences of Teen Pregnancy Today

It is important to stress that our analysis also documents the disadvantages of teen pregnancy in WEIRD (as defined by Henrich et al., 2010) populations, such as the United States in 1990, especially in younger teens. Where both surgical births and birth control are widely available and where teen pregnancy is usually associated with social and behavioral risk factors, teen pregnancies are very likely to have many negative long-term consequences for the mother and infant (Black et al., 2012). Pregnancies in teens younger than 16 years had much poorer infant outcomes and were more likely to have an operative delivery (forceps or vacuum extraction). Thus, efforts to prevent teen pregnancies are highly desirable and are not in any way contradicted by any of our conclusions concerning past selection on female life history.

Despite the disadvantages of teen pregnancy in contemporary WEIRD societies, we suggest that our findings are relevant to understanding human evolution, in particular women’s life history and men’s mating preferences. Given the obvious evolutionary importance of a successful vaginal delivery, early first pregnancies and a male preference for nubility were probably advantageous in the premodern era. They would have produced the best odds of a successful reproductive outcome—a benefit to mother, father, and infant.

Limitations

The use of data from a modern North American population to gauge probable reproductive outcomes in evolutionarily relevant populations is not ideal; but because of the extremely recent nature of shifts in human reproductive ecology, the relevant underlying biology may be largely unchanged. By controlling for evolutionarily novel risk factors which make “teen pregnancy” disadvantageous in contemporary populations, the results should have some validity for natural-fertility populations where first pregnancies in 16–20 year-olds are normative. Our findings of a much lower risk of critically necessary surgical births and a slightly lower risk of neonatal deaths for mothers in the 16–20 years age group (with controls for social and behavioral risk factors) are consistent with findings from a large variety of non-Western countries (Conde-Agudelo et al., 2000; Ganchimeg et al., 2013, 2014) and from 18th–19th century Germany (Knodel & Hermalin, 1984).

It might be argued that modern American obstetric practices are quite different from those in traditional societies where experienced midwives play a crucial role, but the uniformity of findings in the US and in three different samples of 23, 29, and 18 non-Western countries points to common underlying factors in reproductive biology and suggests that similar biological factors are likely to have been operating in the EEA.

Because all of the many available studies uniformly show a decrease in obstetric complications requiring a C-section in the 16–19 years age group, this is more likely to be species-typical. Limiting the analysis to C-sections associated with complications that would be likely to cause significant harm to the mother or fetus without surgical intervention may give some indication of the risk in natural-fertility populations without access to surgical deliveries.

Traditional populations are also likely to have much higher infant and child mortality: Infant mortality has been estimated at 27% in the EEA (Volk & Atkinson, 2013), compared with 0.8% in the 1990 data set. However, our analysis controlling for contemporary maternal risk factors suggests that the infants of nubile mothers in the past would likely have done as well or better than those of older mothers, as also indicated by findings from 18th to19th century Germany, where the overall infant mortality rate was 23% (Knodel & Hermalin, 1984).

When comparable infant outcomes are combined with the much lower risk of death in childbirth from complications of labor and delivery, it seems likely that nubile women would have been the most successful primiparas, thus suggesting an adaptive explanation for the timing of first births in a wide range of forager and subsistence populations (Kramer & Lancaster, 2010; Lassek & Gaulin, 2019; Symons, 1979; Walker, 2019).

From 2016... Glaciers, gendered knowledge, systems of scientific domination, & alternative representations of glaciers: A feminist glaciology framework for global environmental change research

From 2016... Glaciers, gender, and science: A feminist glaciology framework for global environmental change research. Mark Carey et al. Progress in Human Geography, January 10, 2016. https://doi.org/10.1177/0309132515623368

Abstract: Glaciers are key icons of climate change and global environmental change. However, the relationships among gender, science, and glaciers – particularly related to epistemological questions about the production of glaciological knowledge – remain understudied. This paper thus proposes a feminist glaciology framework with four key components: 1) knowledge producers; (2) gendered science and knowledge; (3) systems of scientific domination; and (4) alternative representations of glaciers. Merging feminist postcolonial science studies and feminist political ecology, the feminist glaciology framework generates robust analysis of gender, power, and epistemologies in dynamic social-ecological systems, thereby leading to more just and equitable science and human-ice interactions.

Keywords: feminist glaciology, feminist political ecology, feminist postcolonial science studies, folk glaciology, glacier impacts, glaciers and society

VII Conclusions

Ice is not just ice. The dominant way Western societies understand it through the science of glaciology is not a neutral representation of nature. The feminist glaciology framework draws attention to those who dominate and frame the production of glaciological knowledge, the gendered discourses of science and knowledge, and the ways in which colonial, military, and geopolitical domination co-constitute glaciological knowledge. Even in a globalized age where the place of women and indigenous people has improved markedly in some parts of the world, masculinist discourses continue to dominate, in subtle and determinative ways. Feminist glaciology advocates for a shift of preoccupations in research, policy, and public perceptions from the physical and seemingly natural, to a broader consideration of ‘cryoscapes’, the human, and the insights and potentials of alternative ice narratives and folk glaciologies. The critique and framework outlined here illuminate experiences and narratives that emerged historically but remain potent today. Public discourse on the cryosphere continues to privilege, quite explicitly, manly endeavours and adventures in the field, and those who conduct their science in the manner of masculinist glaciologists and other field scientists of decades and centuries past. A new documentary by French filmmaker Luc Jacquet (2015) about the preeminent French glaciologist and geochemist Claude Lorius perpetuates narratives of heroic domination of nature, while, in interesting ways, noting that ‘triumphant man’ is responsible for the global problems that make Lorius’ research so necessary. At the same time, in the midst of extensive coverage of the polar regions in the context of climate change, the New York Times has published articles that foreground the dangerous field in Greenland, thereby validating manly, heroic fieldwork while simultaneously relegating work with models and computers to something like ‘armchair glaciology’ (Davenport et al., 2015; Gertner, 2015). Unlike past narratives, there are subtleties and tensions within these public discourses, especially as they often seek to see scientific work in more detail, a detail that can soften or undercut the individual exertions on display. However, they still privilege stereotypical and masculinist practices of glaciology. Other narratives, however, challenge these practices, thereby generating alternative approaches to ice. Emerging from Australia, the Homeward Bound initiative plans a ‘state of the art leadership and strategic program for 78 women in science from around the globe’ to travel to Antarctica in late 2016, one of its aims being to ‘explore how women at the leadership table might give us a more sustainable future’ (Homeward Bound, 2015). The call for a feminist glaciology is not limited to ice and glaciers, but is a larger intervention into global environmental change (and especially climate change) research and policy. As international negotiations remain stalled and governmental commitments to change and reform are fitful and seemingly ineffectual, those studying environmental change and aware of its significant effects and dangerous potentials continue to search for ways of stemming the tides of change as well as forming just and equitable global structures for addressing it. The feminist glaciology framework articulates with these larger quests in at least two ways. First, it repeats the demands for increased presence of humanities and social science perspectives in global environmental change research, policy, and broader public discourse. Many humanities and social science disciplines and sub-disciplines have given significant attention to these issues, but there remain boundaries between these analyses and those considered central to the environmental change question. The natural sciences that drive and undergird environmental change policy are often asked by decision-makers and the media to speak for society or frame research and policy questions for humanity. But the natural sciences are not equipped to understand the complexities and potentialities of human societies, or to recognize the ways in which science and knowledge have historically been linked to imperial and hegemonic capitalist agendas. Feminist glaciology participates in this broader movement by suggesting richer conceptions of humanenvironment relations, and highlighting the disempowering and forestalling qualities of an unexamined and totalizing science. Second, we reiterate the need not only to appreciate the differential impacts of environmental change on different groups of people – men and women, rich and poor, North and South – but to understand how the science that guides attempted solutions may in fact perpetuate differences because they are, essentially, built on and draw their epistemic power from differentiation and marginalization. Struggles over authority and legitimacy play out in many obvious ways in climate change negotiations. Struggles also happen in less obvious ways, such as in the environmental change research underpinning climate politics. Analysts and practitioners must recognize the ways in which more-than-scientific, non-Western, nonmasculinist modes of knowledge, thinking, and action are marginalized. The response to simplistic ‘ice is just ice’ discourse is not merely to foreground or single out women and their experiences – that would simply perpetuate binaries and boundaries and ignore deeper foundations. Rather, it is a larger integration of human approaches and sensibilities with the existing dominant physical sciences. Global environmental change research must pluralize its ontologies, epistemologies, and sensibilities. Though there is ever-increasing evidence to guarantee future temperature increases, what remains uncertain are the human structures and ideas mobilized to cope with environmental changes as well as to forestall potentially worse outcomes. If we constitute glaciological and global environmental change research differently, we can constitute our future, our gender relations, and our international political economic relations more justly and equitably.

The Big Five predict numerous preferences, decisions, and behaviors—but why? To help answer this key question, the present research develops the sociocultural norm perspective

Eck, J., & Gebauer, J. E. (2021). A sociocultural norm perspective on Big Five prediction. Journal of Personality and Social Psychology, Sep 2021. https://doi.org/10.1037/pspp0000387

Abstract: The Big Five predict numerous preferences, decisions, and behaviors—but why? To help answer this key question, the present research develops the sociocultural norm perspective (SNP) on Big Five prediction—a critical revision and extension of the sociocultural motives perspective. The SNP states: Agreeableness, Extraversion, and Conscientiousness predict outcomes positively if those outcomes are socioculturally normative. Openness, by contrast, predicts outcomes negatively if they are socioculturally normative. Moreover, the SNP specifies unique mechanisms that underlie those predictions. Two mechanisms are social (social trust for Agreeableness, social attention for Extraversion) and two are cognitive (rational thought for Conscientiousness, independent thought for Openness). The present research develops the SNP by means of three large-scale experiments (Ntotal = 7,404), which used a new, tailor-made experimental paradigm—the minimal norm paradigm. Overall, the SNP provides norm-based, culture-focused, and mechanism-attentive explanations for why the Big Five predict their outcomes. The SNP also has broader relevance: It helps explain why Big Five effects vary across cultures and, thus, dispels the view that such variation threatens the validity of the Big Five. It suggests that the psychology of norms would benefit from attention to the Big Five. Finally, it helps bridge personality, social, and cross-cultural psychology by integrating their key concepts—the Big Five, conformity, and sociocultural norms.

Stay-at-home orders in Mexico led to a fall in abortions of around 25%; fewer unwanted pregnancies from decreased sexual activity is at most 9.8% of the total fall in abortions

The unintended effects of the COVID-19 pandemic and stay-at-home orders on abortions. Fernanda Marquez-Padilla & Biani Saavedra. Journal of Population Economics, Sep 15 2021. https://rd.springer.com/article/10.1007/s00148-021-00874-x

Abstract: We study the effect of the COVID-19 pandemic and of government mandated mitigation policies on the number of abortions performed by Mexico City’s public abortion program. We find that the COVID-19 pandemic and stay-at-home orders (SAHO) implemented in Mexico led to unintended consequences for women’s sexual and reproductive health. Using difference-in-differences and event study analyses, we show that SAHO and the pandemic led to a fall in abortions of around 25% and find no evidence that unsafe abortions increased. We find a decrease in the share of single and teenage women getting abortions, arguably due to fewer unwanted pregnancies from decreased sexual activity, and estimate that at most 9.8% of the total fall in abortions can be attributed to this. We complement our analysis using call data from a government helpline and show that the SAHO time period led to fewer abortion- and contraception-related calls but to an increase in pregnancy-related calls.

Discussion and conclusions

We find that the COVID-19 pandemic and SAHO implemented to mitigate the spread of the virus led to a significant decline in the number of abortions performed by CDMX’s public abortion program. We show that the effects were driven by municipalities more likely to comply with SAHO and present evidence of anticipatory effects to the policy. We find that the composition of women getting abortions changed after the lockdown, where single and adolescent women were less likely to get an abortion. We interpret this compositional change as reflecting a decline in unwanted pregnancies for these groups of women (in addition to stronger mobility restrictions). Conditional on municipality of residence, SAHO and the pandemic did not affect women’s average SES as measured by their schooling, suggesting that the reduction in abortions is not explained by changes in women’s preferences over continuing with a pregnancy.

While most of our analysis focuses on the sudden start of SAHO in Mexico, it is hard to separate the total effect of the pandemic from the effects of the SAHO, which are likely to have affected abortion simultaneously and likely in correlated ways—as the fact that effects were stronger for municipalities with high COVID-19 mortality would suggest. We believe that in any case, identifying the total effect of the pandemic on abortions is both relevant and important.

We find no evidence that the reduction in ILE abortions led to an increase in unsafe abortions as hospital discharge data for ARM shows no increases following SAHO, but rather falls following the general hospital usage trends. While abortions not obtained through the public ILE program may have been obtained in the private sector, we show that at least for the case of births we do not observe a shift from public to private healthcare services, mitigating concerns that our results merely suggest a shift from public to private abortions. Our data does not rule out the possibility that self-managed abortions may have compensated for ILE’s reduction in the supply of abortions.

We present additional evidence from helpline calls consistent with SAHO affecting women’s ability to access safe and legal abortions. This is likely to be due to limited access (a fall in the supply of abortions by public health facilities and mobility restrictions), fear of visiting healthcare facilities, and to a loss of women’s autonomy and privacy.

Taken the evidence together, our results present some of the first empirical evidence anticipating the potential effects of COVID-19 and SAHO on fertility, suggesting evidence consistent with an increase in unwanted pregnancies after SAHO started. Its potential relation with increased domestic violence and sexual abuse within the home highlights the importance of focusing policy efforts on providing more and better reproductive health services to women.

Some possible policy recommendations may include a “hotline” and/or telemedicine alternatives for safe misoprostol use in order to make home abortions safe (Drovetta 2015; Donovan 2019) and moving sexual and reproductive health services and care out of hospitals or into the community, in addition to improving the distribution of contraception (Cousins 2020).

Seven individuals who developed a rare and severe type of anterograde amnesia following damage to their medial temporal lobes: Patients’ perceptions of themselves were stuck in the past, unable to see the changes others saw

Who Are You? The Study of Personality in Patients With Anterograde Amnesia. McKenna M. Garland et al. Psychological Science, September 14, 2021. https://doi.org/10.1177/09567976211007463

Abstract: Little is known about the role of declarative memory in the ongoing perception of one’s personality. Seven individuals who developed a rare and severe type of anterograde amnesia following damage to their medial temporal lobes were identified from our neurological patient registry. We examined the stability of their personality ratings on the Big Five Inventory over five retest periods and assessed the accuracy of their ratings via analyses of self–caregiver agreement. The patients portrayed a stable sense of self over the course of 1 year. However, their self-ratings differed from those provided by the caregivers. Intriguingly, these discrepancies diminished when caregivers retrospectively rated the patients’ personalities prior to their brain injury, suggesting that patients’ perceptions of themselves were stuck in the past. We interpret our findings to indicate that the ability to form new declarative memories is not required for maintaining a stable sense of self but may be important for updating one’s sense of self over time.

Keywords: personality, amnesia, Big Five, medial temporal lobe, hippocampus, self–other agreement, personality stability, memory, neuropsychology

Cats show up—on average—in about 5% of the remembered dreams, which are very positive, much more so than dreams in general, or dog dreams, indicating that waking-life experiences with cats are also mostly positive

Schredl, M., Bailer, C., Weigel, M. S., & Welt, M. S. (2021). Dreaming about cats: An online survey. Dreaming, Sep 2021. https://doi.org/10.1037/drm0000176

Abstract: Cats have lived with humankind for millennia, and one would expect—according to the continuity hypothesis of dreaming—that cats also show up in dreams, more often when the relationship is between the cat and a human is closer, for example, when she or he is a cat owner. Previous studies showed that the percentage of dreams that included cats ranges from 0.4% to 2%, but studies relating waking-life experiences with cats with dreams about cats have not been carried out. In total, 1,695 persons (960 women, 735 men; mean age: 53.84 ± 13.99 years) completed an online survey that included questions about dreams and waking-life experiences with cats. The findings indicate that cats show up—on average—in about 5% of the remembered dreams, but the percentage is much higher in cat owners or persons with a close contact to cats. Interestingly, the cat dream percentage was lower compared to the dog dream percentage, elicited in a previous study. Moreover, proximity during sleep and whether the cat stays in the household is also related to a higher percentage of dreams that include cats. Cat dreams are very positive, much more so than dreams in general, indicating that waking-life experiences with cats are also mostly positive. A small percentage of participants indicted that they had negative experiences with cats in the past; this is related to the frequency of dreams with threatening cats. The results support the continuity hypothesis, and it would be very interesting to conduct content analytic studies with dream samples obtained from pet owners to learn more about the variety of interactions between dreamers and their pets as they are reflected in dreams.

Asocial free-ranging squirrels: Bolder individuals maintained larger core areas than shyer individuals; more proactive and sociable personality types had greater access to a preferred resource

Bridging animal personality with space use and resource use in a free-ranging population of an asocial ground squirrel. Jaclyn R. Aliperti et al. Animal Behaviour, September 10 2021. https://doi.org/10.1016/j.anbehav.2021.07.019

Highlights

• Bolder individuals maintained larger core areas than shyer individuals.

• More active and bolder individuals moved faster under natural conditions.

• More proactive and sociable personality types had greater access to a preferred resource.

• Among-individual variation in activity and sociability was positively correlated.

• Our data support personality-dependent use of space and resources in nature.

Abstract: Consistent individual differences in behaviour, or personality, likely influence patterns of space use and resource use in wild animals. However, studies on personality-dependent space use in natural ecosystems remain rare due to the difficulty of obtaining paired data sets on spatial dynamics and repeated personality measures from marked animals. We used repeated standardized assays (open field, mirror image stimulation, flight initiation distance and behaviour in trap) to perform the first characterization of personality in a free-ranging population of golden-mantled ground squirrels, Callospermophilus lateralis. We then used multilevel modelling to determine whether personality influenced 95% home range size, 50% core area size, movement speed or use of a preferred resource (‘perches’, vision-enhancing prominences such as rocks, which enhance survival) in nature. Data collected over 3 years showed that individual squirrels consistently differed in activity, sociability, boldness and aggressiveness (adjusted repeatability 0.16–0.44) and that activity was correlated with sociability (posterior mean correlation [95% credible interval] = 0.65 [0.39, 0.87]). We did not find an effect of personality on home range size, but bolder individuals maintained larger core areas than shyer individuals. More active and bolder individuals moved faster under natural conditions compared to their less active and shyer conspecifics. Individuals that scored higher for all four personality traits had more perches in both their home ranges and core areas compared to individuals with lower personality scores. Our results are indicative of personality-dependent space use and resource use in this study system. We hope our study will inspire future research that links animal personality with spatial ecology to inform wildlife management in natural ecosystems.

Keywords: animal personalityanimal temperamentbehavioural typeCallospermophilus lateralisground squirrelmovementrepeatabilityresource usesociabilityspace use

Contrary to many scholars’ intuitions, social aggregates like ethnic, linguistic, and religious groups, as well as diverse socio-demographic categories, add negligible explained variance to that already captured by nations

On “Nationology”: The Gravitational Field of National Culture. Plamen Akaliyski et al. Journal of Cross-Cultural Psychology, September 11, 2021. https://doi.org/10.1177/00220221211044780

Abstract: Nations have been questioned as meaningful units for analyzing culture due to their allegedly limited variance-capturing power and large internal heterogeneity. Against this skepticism, we argue that culture is by definition a collective phenomenon and focusing on individual differences contradicts the very concept of culture. Through the “miracle of aggregation,” we can eliminate random noise and arbitrary variation at the individual level in order to distill the central cultural tendencies of nations. Accordingly, we depict national culture as a gravitational field that socializes individuals into the orbit of a nation’s central cultural tendency. Even though individuals are also exposed to other gravitational forces, subcultures in turn gravitate within the limited orbit of their national culture. Using data from the World Values Survey, we show that individual values cluster in concentric circles around their nation’s cultural gravity center. We reveal the miracle of aggregation by demonstrating that nations capture the bulk of the variation in the individuals’ cultural values once they are aggregated into lower-level territorial units such as towns and sub-national regions. We visualize the gravitational force of national cultures by plotting various intra-national groups from five large countries that form distinct national clusters. Contrary to many scholars’ intuitions, alternative social aggregates, such as ethnic, linguistic, and religious groups, as well as diverse socio-demographic categories, add negligible explained variance to that already captured by nations.

Keywords: culture, nation, identity, units of analysis, cultural homogeneity

The Bayesian brain: Agents set the balance between prior knowledge and incoming evidence based on how reliable or ‘precise’ these different sources of information are — lending the most weight to that which is most reliable

Precision and the Bayesian brain. Daniel Yon, Chris D. Frith. Current Biology, V 31, Issue 17, PR1026-R1032, Sep 13 2021. https://doi.org/10.1016/j.cub.2021.07.044

Summary: Scientific thinking about the minds of humans and other animals has been transformed by the idea that the brain is Bayesian. A cornerstone of this idea is that agents set the balance between prior knowledge and incoming evidence based on how reliable or ‘precise’ these different sources of information are — lending the most weight to that which is most reliable. This concept of precision has crept into several branches of cognitive science and is a lynchpin of emerging ideas in computational psychiatry — where unusual beliefs or experiences are explained as abnormalities in how the brain estimates precision. But what precisely is precision? In this Primer we explain how precision has found its way into classic and contemporary models of perception, learning, self-awareness, and social interaction. We also chart how ideas around precision are beginning to change in radical ways, meaning we must get more precise about how precision works.

Precise and imprecise percepts

Imagine you are walking a particularly disobedient dog. After being let off the leash he leaps into the bushes, and you have to dive in to fetch him out. But you are not entirely sure where he is. You hear the sound of twigs cracking to the left, but you see the leaves shake to the right. Where should you jump in to catch him?

Locating your dog based on a combination of sight and sound is an example of a general class of multisensory integration problems where our perceptual systems have to triangulate different sensory signals. In our example, the visual signal (shaking leaves to the right) and the auditory signal (cracking twigs to the left) both tell us something about one feature of the environment (the dog’s location), and so it makes sense to combine them. But how? A simple approach could be for our brain to average them together — if sight says right and sound says left, we should dive in straight ahead.

But simple averaging turns out to be suboptimal when some signals are more reliable than others. For example, the spatial acuity of vision is much greater than that of hearing, meaning visual estimates of location are considerably more precise than auditory ones. This insight was formalised in Marc Ernst and Martin Banks’ Bayesian model of multisensory integration, which assumes that our perceptual systems combine different signals according to their reliability or uncertainty. Agents are thought to achieve this by keeping track of the noise or variance in different sensory modalities — with low noise taken as an index of high precision — and affording a higher weight to those channels that are more precise.

This idea of ‘precision-weighting’ provides a good account of near-optimal cue integration seen in humans and other animals. Typically, we won’t jump straight to catch the dog, but will veer off to the right as our brains give more credence to the more precise visual signal. Importantly, this idea can also explain why perception sometimes errs: such as when we are fooled by a ventriloquist’s dummy. It is common to say that the ventriloquist ‘throws their voice’ so it appears to be coming from the silent puppet. In fact, the illusion of the speaking doll emerges because our perceptual systems infer that the visual and auditory signals come from a common source, but give more weight to what we see than what we hear as we try to pinpoint where this source is located. The perceptual experience is false — the voice is not coming from the dummy — but this can still be thought of as an optimal inference from the brain’s perspective, given that coincident sensory signals often do come from a common source, and visual information about the location of these sources is typically so much more precise.

The Psychological and Socio-Political Consequences of Infectious Diseases: Authoritarianism, Governance, and Nonzoonotic (Human-to-Human) Infection Transmission

The Psychological and Socio-Political Consequences of Infectious Diseases: Authoritarianism, Governance, and Nonzoonotic (Human-to-Human) Infection Transmission. Leor Zmigrod, Tobias Ebert, Friedrich M. Götz, Peter Jason Rentfrow. Journal of Social and Political Psychology, Volume 9 (2), Sep 9 2021. https://jspp.psychopen.eu/index.php/jspp/article/view/7297

Abstract: What are the socio-political consequences of infectious diseases? Humans have evolved to avoid disease and infection, resulting in a set of psychological mechanisms that promote disease-avoidance, referred to as the behavioral immune system (BIS). One manifestation of the BIS is the cautious avoidance of unfamiliar, foreign, or potentially contaminating stimuli. Specifically, when disease infection risk is salient or prevalent, authoritarian attitudes can emerge that seek to avoid and reject foreign outgroups while favoring homogenous, familiar ingroups. In the largest study conducted on the topic to date (N > 240,000), elevated regional levels of infectious pathogens were related to more authoritarian attitudes on three geographical levels: across U.S. metropolitan regions, U.S. states, and cross-culturally across 47 countries. The link between pathogen prevalence and authoritarian psychological dispositions predicted conservative voting behavior in the 2016 U.S. Presidential Election and more authoritarian governance and state laws, in which one group of people imposes asymmetrical laws on others in a hierarchical structure. Furthermore, cross-cultural analysis illustrated that the relationship between infectious diseases and authoritarianism was pronounced for infectious diseases that can be acquired from other humans (nonzoonotic), and does not generalize to other infectious diseases that can only be acquired from non-human species (zoonotic diseases). At a time of heightened awareness of infectious diseases, the current findings are important reminders that public health and ecology can have ramifications for socio-political attitudes by shaping how citizens vote and are governed.

Leftists Possess More National Consensus in Europe in One of Two Data Sets (as it happens in the US)

Leftists Possess More National Consensus in Europe in One of Two Data Sets. Mark J. Brandt et al. Social Psychological and Personality Science, September 13, 2021. https://doi.org/10.1177/19485506211041825

Abstract: A regularity in the U.S. American politics is that liberals have more policy consensus than do conservatives, and both ideological groups have more consensus than moderates. One explanation for this is that conservatives’ local conformity paradoxically results in less consensus than liberals at the national level. If so, then the liberal consensus effect should also be observed in other countries. We test this using data from Europe. In the European Social Survey (country N = 38, participant N = 376,129), we find that on average leftists have more consensus than do rightists; however, we do not find this using the Eurobarometer (country N = 18, participant N = 375,830). In both data sources, we also observe variation in ideological differences between countries. These results suggest that there is a liberal/leftist consensus effect on average, that can be found in Europe and the United States, but there are also exceptions.

Keywords: ideology, consensus, belief systems, Europe, ideological differences

Older adults were significantly less likely to cheat and had higher ratings of honesty–humility compared to younger adults; greater honesty–humility predicted lower cheating behavior

Examining honesty–humility and cheating behaviors across younger and older adults. Alison M. O’Connor et al. International Journal of Behavioral Development, September 13, 2021. https://doi.org/10.1177/01650254211039022

Abstract: Self-report research indicates that dishonesty decreases across adulthood; however, behavioral measures of dishonesty have yet to be examined across younger and older adults. The present study examined younger and older adults’ cheating behaviors in relation to their self-reported honesty–humility. Younger (N = 112) and older adults (N = 85) completed a matrix task where they had the opportunity to falsely inflate their performance. Participants also completed the self-report measure of honesty–humility from the HEXACO-PI-R. Older adults were significantly less likely to cheat and had higher ratings of honesty–humility compared to younger adults. Greater honesty–humility predicted lower cheating behavior. These results demonstrate that older adults show greater rates of honesty and humility compared to younger adults using both behavioral and self-report methods.

Keywords: Deception, cheating, aging, honesty, HEXACO

An Industrial Organization Perspective on Productivity

An Industrial Organization Perspective on Productivity. Jan De Loecker & Chad Syverson. NBER Working Paper 29229, Sep 2021. https://www.nber.org/papers/w29229

Abstract: This chapter overviews productivity research from an industrial organization perspective. We focus on what is known and what still needs to be learned about the productivity levels and dynamics of individual producers, but also how these interact through markets and industries to influence productivity aggregates. We overview productivity concepts, facts, data, measurement, analysis, and open questions.

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This chapter focuses on the implications and applications of productivity analysis within Industrial Organization. There is a long tradition in IO of studying productivityrelated topics like allocative eciency, technological change, regulatory effects, cost effciencies in merger analysis, and returns to scale, to name a few. The term productivity is, however, more often than not used in a fairly loose sense, usually referring to a measure of performance. In this chapter we make an explicit distinction between productivity in a strict production eciency sense, on the one hand, and performance on the other. The study of production eciency, the rate at which a producer can convert a bundle of inputs into a unit of output, is in essence about the technical relationship between output and inputs. Performance captures a variety of measures, but as this chapter will highlight, it is intimately related to eciency. However, the distinction can be crucial when analyzing the very topics listed above.

1.1 Background and Focus

While having a long history in economics, the past few decades have seen the productivity analysis of individual producers and the corresponding industry- and economy-wide aggregates become a central topic in both academic and policy circles. This renewed interest has paralleled at least three main developments.

First, over the last two decades the access to micro data has exploded. At the turn of the century, only a few large-scale producer-level datasets existed, with limited access to researchers. In contrast, the current list of countries for which micro census data is available (in manufacturing, at least) contains a rather large share of the world. In addition, private data providers have emerged offering comprehensive accounting data capturing typical variables used in productivity analysis, through the reporting of balance sheets and income and loss statements.

Second, accompanying the increased access to micro data has been a renewed interest in the estimation and identification of production functions. These are of course key objects of interest for most productivity analyses, both for their own sake as well as supplyside inputs into equilibrium analysis. This research has focused on obtaining reliable productivity measures for sets of producers when, as is the case, the researcher cannot directly observe productivity but producers can. This leads to two well-known biases, the simultaneity and selection biases, that researchers must face.

Third is the prominent role of productivity analysis in forming and executing economic policy. While policymakers still mostly focus on industry- or economy-wide aggregates, there is increasing recognition that this analysis is often most informative when built from the ground up using micro data. The melding of data, methods, and economically oriented policy analysis has spurred informative interactions among microeconomists, macroeconomists, and policymakers that have created many insights into productivity.  Our intent in this chapter is to organize and review the intellectual underlayment of this burgeoning literature. There are many facets. Our coverage includes key conceptual issues, facts about micro-level productivity, models of markets with heterogeneous productivity producers, measurement and data, productivity estimation, the positive and normative implications of the static and dynamic allocation of activity across heterogeneous producers, and an overview of what we expect to be active areas of work in the near future. We do this while taking stock of several decades of empirical work on productivity using micro data. We will unavoidably miss certain dimensions, and simple space constraints mean we cannot do justice to many contributions and insights from this extensive literature. We do hope, however, to offer a structured view on the field of productivity and how Industrial Organization scholars have contributed.

1.2 Productivity Conceptualized

Productivity is conceptualized in a number of related ways. All productivity metrics in one form or another measure how much output producers obtain from a given set of inputs. As such they are measures of the ecacy of the supply side of the economy (though \ecacy" need not always be synonymous with social welfare).  An interpretation of productivity as an economic primitive is as a factor-neutral (aka Hicks-neutral) shifter of the production function.1 Consider the general production function Q = Omega * F(.), where Q is output and F() is a function of observable inputs capital such as capital, labor and intermediate inputs.  Omega is productivity, the factor-neutral shifter.  It reflects variations in output not explained by shifts in the observable inputs that act through F(). A higher value of Omega implies the producer will obtain more output from a given set of inputs. That is, it denotes a shift in the production function's isoquants down and to the left.

A second conceptualization is empirical: productivity as a ratio of output to inputs.  This is tightly related to the production-function-shifter interpretation above. This can be seen by isolating productivity from the production function: Omega = Q / F(.) . A is clearly an output-to-input ratio. Here, where output is divided by a combination of observable inputs, the productivity concept is named total factor productivity (TFP) (it is also sometimes called multifactor productivity, MFP). There are also single-factor productivity measures, where output is divided by the amount of a single input, most commonly labor; i.e., labor productivity. Because single-factor productivity measures can be affected not just by shifts in TFP but factor intensity decisions as well, TFP measures are often conceptually preferable. On the other hand, labor productivity is often easier to measure than TFP.

A third conceptualization is of productivity as a shifter of the producer's cost curve.  Higher productivity shifts down the cost curve; that is, at the producer's cost-minimizing combination of inputs, its total cost of producing a given quantity is lower, the higher is its TFP level. This productivity conceptualization is related to the other two because the cost function is the value function of the producer's cost minimization problem, which takes the production function as its constraint. This cost function shifts down when productivity rises.

Because it plays such an important role in the producer's production technology, measuring productivity and its influence on outcomes is the subject of an enormous literature.

This work has found in many disparate settings that, as an empirical matter, productivity is hugely important in explaining the fortunes of producers, their workers, their suppliers, and their customers. We survey work on both the measurement and effects of productivity below.

Survey data show that up to 44% of the public support politically motivated violence; but estimates of support for partisan violence are too large; large majority support charging suspects who commit acts of political violence

Westwood, Sean, Justin Grimmer, Matthew Tyler, and Clayton M. Nall. 2021. “Political Violence.” OSF Preprints. September 14. doi:10.31219/osf.io/a8m3n

Abstract: Political scientists, pundits, and citizens worry that America is entering a new period of violent partisan conflict. Provocative survey data show that up to 44% of the public support politically motivated violence in hypothetical scenarios. Yet, despite media attention, political violence is rare, amounting to a little more than 1% of violent hate crimes in the United States. We reconcile these seemingly conflicting facts with three large survey experiments (N=3,041), demonstrating that self-reported attitudes on political violence are biased upwards because of disengaged respondents, differing interpretations about questions relating to political violence, and personal dispositions towards violence that are unrelated to politics. Our estimates show that, depending on how the question is asked, existing estimates of support for partisan violence are 30-900% too large, and nearly all respondents support charging suspects who commit acts of political violence with a criminal offenses. These findings suggest that although recent acts of political violence dominate the news, they do not portend a new era of violent conflict.

Widespread Reach, not much Influence of Online News: In the absence of rigorous research on causal effects on mass political attitudes and behaviour, we do not know whether the impact of the new media is strong or weak

Widespread Reach, not much Influence: Online News and Mass Political Attitudes and Behaviour in the UK. Kenneth Newton. The Political Quarterly, Sep 2021. https://onlinelibrary.wiley.com/doi/epdf/10.1111/1467-923X.13052

Abstract: In spite of the concern about the political influence of the new digital media, especially social media, a large amount of circumstantial evidence suggests that their impact on mass politicala ttitudes and behaviour, which is the focus of this article, may be small. Online news is less widely trusted than the news consumed via the legacy media (TV, radio, newspapers and magazines) and social media are least trusted of all. Most people rely heavily on the mainstream legacy media for their news, which are also the most popular online news sources—especially the BBC and much the same news is accessed on the new and old media. The majority of people have a fairly mixed diet of politically neutral and partisan news and there is little evidence of political ‘echo chambers’—even among the small minority that rely heavily on a single, partisan source. All age groups gather their news in similar ways, including the youngest, who make heavy use of the social media. Nevertheless, in the absence of rigorous research on causal effects on mass political attitudes and behaviour, we do not know whether the impact of the new media is strong or weak. The circumstantial evidence suggests they are likely to be weak.

Keywords: online news, heritage media, social media, news diets

Chemosensory anxiety signals seem to act contagiously; reduce trust as well as risk behavior; predominantly affect women; & act independent of odor concentration

It’s trust or risk? Chemosensory anxiety signals affect bargaining in women. Lukas Meister, Bettina M. Pause. Biological Psychology, Volume 162, May 2021, 108114. https://doi.org/10.1016/j.biopsycho.2021.108114

Highlights

• Chemosensory anxiety signals seem to act contagiously.

• Chemosensory anxiety signals reduce trust as well as risk behavior.

• Chemosensory anxiety signals predominantly affect women.

• Chemosensory anxiety signals act independent of odor concentration.

Abstract

It is well documented how chemosensory anxiety signals affect the perceiver’s physiology, however, much less is known about effects on overt social behavior. The aim of the present study was to investigate the effects of chemosensory anxiety signals on trust and risk behavior in men and women. Axillary sweat samples were collected from 22 men during the experience of social anxiety, and during a sport control condition. In a series of five studies, the chemosensory stimuli were presented via an olfactometer to 214 participants acting as investors in a bargaining task either in interaction with a fictitious human co-player (trust condition) or with a computer program (risk condition). It could be shown that chemosensory anxiety signals reduce trust and risk behavior in women. In men, no effects were observed. Chemosensory anxiety is discussed to be transmitted contagiously, preferentially in women.

Keywords: Chemosensory communicationTrustRiskBargainingTSST-GAnxiety

Immigration to the USA adds 1.4 and 1.5 years to male & female life expectancy; immigration contributed roughly half of life expectancy gains 2007-2017; the post-2010 mortality stagnation is due to adverse trends among the US-born

Immigration and improvements in American life expectancy. Arun S. Hendi, Jessica Y. Ho. SSM - Population Health, Volume 15, September 2021, 100914. https://doi.org/10.1016/j.ssmph.2021.100914

Highlights

• Immigration adds 1.4 and 1.5 years to male and female life expectancy, respectively.

• Immigration contributed roughly half of life expectancy gains between 2007 and 2017.

• The post-2010 US mortality stagnation is due to adverse trends among the US-born.

• Foreign-born life expectancies rival those of the world leaders in longevity.

Abstract: Despite the immigrant mortality advantage and the increasing share of the population born abroad, relatively little is known about how immigration has impacted trends in US life expectancy. How immigrants contribute to national life expectancy trends is of increasing interest, particularly in the context of an unprecedented stagnation in American mortality. We find that immigration increases US life expectancy by 1.5 years for men and 1.4 years for women. Over half of these contributions occur at the prime working ages of 25–64. The difference between foreign-born and US-born mortality has grown substantially since 1990, with the ratio of US-born to foreign-born mortality rates nearly doubling by 2017. In that year, foreign-born life expectancy reached 81.4 and 85.7 years for men and women, respectively—7.0 and 6.2 years higher than their US-origin counterparts. These life expectancy levels are remarkable by most standards. Foreign-born male life expectancy exceeds that of Swiss men, the world leaders in male life expectancy. Life expectancy for foreign-born women is close to that of Japanese women, the world leaders in female life expectancy. The widening mortality difference between the US-born and foreign-born populations, coupled with an increase in the share of the population born abroad, has been responsible for much of the increase in national life expectancy in recent years. Between 2007 and 2017, foreign-born men and women were responsible for 44% and 60% of national life expectancy improvements. Between 2010 and 2017, immigrants experienced gains while the US-born experienced declines in life expectancy. Thus, nearly all of the post-2010 mortality stagnation is due to adverse trends among the US-born. Without immigrants and their children, national life expectancy in 2017 would be reduced to its 2003 levels. These findings demonstrate that immigration acts to bolster American life expectancy, with particularly valuable contributions at the prime working ages.

Keywords: Life expectancyImmigrationForeign-bornMortalityDemographyTrends

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Foreign-born male life expectancy exceeds that of Swiss men, the world leaders in male life expectancy. Life expectancy for foreign-born women is close to that of Japanese women, the world leaders in female life expectancy.

We observed an association between frequent pornography use and not having had sex in the last year among men (which was in contrast with previous studies), but not women

Malki K, Rahm C, Öberg KG, et al. Frequency of Pornography Use and Sexual Health Outcomes in Sweden: Analysis of a National Probability Survey. J Sex Med 2021;XX:XXX–XXX. Sep 12 2021. https://doi.org/10.1016/j.jsxm.2021.08.003

Abstract

Background: Little is known about pornography use and its relationship with sexual health outcomes in the general population.

Aim: To assess frequency of pornography use and the association of sexual health outcomes with frequent pornography use in Sweden.

Methods: Cross-sectional analysis of 14,135 participants (6,169 men and 7,966 women) aged 16–84 years in a Swedish nationally representative survey from 2017. We used logistic regression to assess the association of sexual health outcomes with use of pornography ≥3 times/wk.

Outcomes: Frequency of pornography use (never; less than once/mo to 3 times/mo; 1–2 times/wk; 3–5 times/wk; and daily or almost daily) and sexual health outcomes (eg, sexual satisfaction and sexual health problems).

Results: In total, 68.7% of men and 27.0% of women used pornography. Among men aged 16–24 years, 17.2% used pornography daily or almost daily, 24.7% used pornography 3–5 d/wk and 23.7% used pornography 1–2 d/wk. Among women aged 16–24 years, the proportions were 1.2% for daily or almost daily, 3.1% for 3–5 times/wk, and 8.6% for 1–2 times/wk. Frequency of pornography use decreased with age among both men and women. While 22.6% of all men and 15.4% of all women reported that their or a sex partner's pornography use predominantly had positive effects on their sex life, 4.7% of men and 4.0% of women reported that the effects were predominantly negative. Variables indicating sexual dissatisfaction and sexual health problems were associated with use of pornography ≥3 times/wk: for example, dissatisfaction with sex life (age-adjusted odds ratio [aOR]: men 2.90 [95% CI 2.40–3.51]; women 1.85 [95% CI 1.09–3.16]), not having sex in the preferred way (aOR: men 2.48 [95% CI 1.92–3.20]; women 3.59 [95% CI 2.00–6.42]) and erection problems (aOR: men 2.18 [95% CI 1.73–2.76]).

Clinical Implications: While frequent pornography use is common, potential effects on sexual health outcomes are likely to differ between individuals.

Strength & Limitations: We used a large and recent nationally representative survey with detailed information regarding frequency of pornography use. The temporality of associations of sexual health variables with frequency of pornography use could not be assessed.

Conclusion: In this analysis of a nationally representative survey in Sweden, we found that frequent pornography use was common among young men; that reporting predominantly positive effects of pornography use on the sex life was more common than reporting predominantly negative effects; and that sexual dissatisfaction and sexual health problems were associated with using pornography ≥3 times/wk.

Key Words: PornographyNational Probability SurveySexual Health OutcomesSexual SatisfactionSexual Dysfunction

We assessed the frequency of pornography use and its association with sexual health outcomes using a large and nationally representative survey from 2017 in Sweden. In line with data presented in the survey report,33 around 70% of men and 30% of women aged 16–84 years used pornography; the frequency was higher in younger age groups and decreased with age. Among men aged 16–24 years, approximately 40% used pornography at least 3 times per week (of which around half used pornography daily or almost daily), and over 20% used pornography 1–2 times/wk. Among women in the same age group approximately 4% used pornography at least 3 times per week and 9% used pornography 1-2 times/wk. While less than 5% of men and women reported that their or a sex partner's pornography use had predominantly negative effects on the sex life, over 20% of men and 15% of women reported predominantly positive effects. Dissatisfaction with the quality and quantity of sexual activity and (especially among men) sexual health problems were associated with using pornography 3 times per week or more.

Data on frequent pornography use have been scarce as most studies have used small online surveys or self-selected samples and published data from population-based surveys have not included fine grained information about the frequency of pornography use.26,28,31,32 Data on weekly or monthly pornography use have been presented for 2 US nationally representative surveys from the past decade, although these surveys have not focused on sexual health outcomes. In the Relationship in America survey from 2014, 40% of men and 19% of women aged 18-23 years had used pornography in the past week.30 In the New Family Structures Study from 2011 to 2012, 47% of men and 21% of women aged 18–23 years reported using pornography once a month or more.30 While more detailed data were not presented for these US surveys, weekly pornography use in our Swedish study vs the Relationship in America survey was more common among young men and less common among young women. While it is possible that pornography use differs between the populations, there may be differences between the surveys in the type of individuals who participated and in how they reported their pornography use. Moreover, our study used more recent data (from 2017) and use of smartphone devices and the availability of online entertainment have increased rapidly in the past years.

In accordance with previous research,10,26,38 we found that a minority of individuals reported that their or a sex partner's pornography use had predominantly negative effects on their sex life and reporting of predominantly positive effects was substantially more common. Importantly, frequent pornography use has been subject to much societal concern due to suggested effects on sexual wellbeing and sexual health problems although the evidence regarding such claims is conflicting.2,10, 11, 12, 13, 14, 15,27 We found associations of frequent pornography use with dissatisfaction with the quantity and quality of sexual activity and among men, with lack of arousal when having sex and erection problems. Moreover, we observed an association between frequent pornography use and not having had sex in the last year among men (which was in contrast with previous studies26,39), but not women. Further, while frequent pornography use was associated with reporting predominantly positive effects on the sex life among both men and women, an association with reporting predominantly negative effects was only observed for men; this is in line with previous observations indicating that self-reported problematic use of pornography is more common among men.

Use of pornography has been associated with changes in behaviors during sexual activity29,40 and it has been hypothesized that frequent pornography use introduces dissatisfaction by affecting expectations on sexual activity.41,42 Moreover, pornography use has been suggested to decrease partnered sexual activity and long-term sexual relationships by providing a more easily available substitute.43 However, it is reasonable to hypothesize that sexual dissatisfaction or not being able to find sex partners might increase pornography use.44 Similarly, while frequent pornography use could be hypothesized to increase the risk of sexual health problems, individuals who experience such problems may also use more pornography. The associations could also be explained by other factors (such as stress and boredom45) associated with frequent pornography use and with sexual dissatisfaction, not having partnered sex (among men) and sexual health problems. In fact, erection problems and some variables indicating sexual dissatisfaction were associated with both reporting of predominantly positive and predominantly negative effects of pornography on the sex life, indicating no consistent directionality in the associations of pornography use, as experienced by the respondents, with such outcomes. While the experience of pornography use, its potential effects on sexual health outcomes and the underlying mechanisms for such possible links are likely to differ greatly between individuals, specific sexual interests and type of pornography consumed,21,27 causal effects of pornography use on the group level can only be established in interventional studies. The findings from this study should be considered as hypothesis generating.

Limitations

We used survey data, which are subject to response and reporting bias,30,46 although such biases might have been mitigated by the use of self-administered questionnaires47, 48, 49 and the weighting of the sample to be representative of the Swedish population with respect to the distribution of gender, age, region, country of birth and educational level. The survey did not define pornography, nor was information available about the type of pornography used and the duration and context of use. The questions used in the survey had not been validated and their interpretation may have differed between participants. Because the data were cross-sectional, we could not assess temporality of the associations of sociodemographic and sexual health variables with the frequency and self-reported effects of pornography use.

Testing Women’s Trust in Other Women and Same-Sex Attracted Males in Three Cultures

Testing Women’s Trust in Other Women and Same-Sex Attracted Males in Three Cultures. Scott W. Semenyna, Francisco R. Gómez Jiménez & Paul L. Vasey. Archives of Sexual Behavior, Sep 8 2021. https://link.springer.com/article/10.1007%2Fs10508-021-02139-w

Abstract: Heterosexual women trust mating-relevant advice received from gay men more than that received from heterosexual women. This trust is predicated on women’s perception that gay men lack ulterior sexual motives and romantically pursue other gay men. However, this trust may not hold in all cultures. For example, in both Samoa and the Istmo Zapotec of Southern Mexico, women take part in mate competition against feminine same-sex attracted males—referred to as fa’afafine and muxe, respectively—who regularly engage in sexual activity with masculine men. The present studies sought to replicate and extend research on women’s trust in males who are same-sex attracted. Experiments were conducted in Canada, Samoa, and the Istmo Zapotec, with women randomly assigned to consider the likelihood of various mate-poaching behaviors performed by either a rival woman or a same-sex attracted male. In Canada, women were more trusting of cisgender gay men than other women. Similarly, Samoan women were more trusting of fa’afafine than other women. In the Istmo Zapotec, women were equally distrustful of women and feminine muxe gunaa, whereas more masculine muxe nguiiu were rated as more trustworthy than women and muxe gunaa. These results illustrate that women’s trust in same-sex attracted males varies both between and within cultural contexts, perhaps impacted by the relative femininity of the male in question.