COVID-19 lockdown: Women did more chores & had less satisfaction; men who were the primary caregiver or were not working fulltime had negative relationship outcomes when they did more housework & parenting

Gendered division of labor during a nationwide COVID-19 lockdown: Implications for relationship problems and satisfaction. Nina Waddell et al. Journal of Social and Personal Relationships, March 2, 2021. https://doi.org/10.1177/0265407521996476

Abstract: COVID-19 lockdowns have required many working parents to balance domestic and paid labor while confined at home. Are women and men equally sharing the workload? Are inequities in the division of labor compromising relationships? Leveraging a pre-pandemic longitudinal study of couples with young children, we examine gender differences in the division and impact of domestic and paid labor during a nationwide COVID-19 lockdown (N = 157 dyads). Women did more of the parenting and housework, whereas men engaged in more paid work and personal time, during the lockdown. Couple members agreed that women’s share of parenting, housework and personal time was unfair, but this did not protect women from the detrimental relationship outcomes associated with an inequitable share of domestic labor. A greater, and more unfair, share of parenting, housework and personal time predicted residual increases in relationship problems and decreases in relationship satisfaction for women. Exploratory analyses indicated that men who were the primary caregiver or were not working fulltime also experienced negative relationship outcomes when they did more housework and parenting. These results substantiate concerns that the COVID-19 pandemic may undermine advances toward gender equality by reinforcing inequitable divisions of labor, thereby damaging women’s relationship wellbeing.

Keywords: COVID-19 lockdown, division of labor, housework, parenting, relationship problems

Discussion

The COVID-19 pandemic poses considerable challenges to couples, including lockdowns forcing working parents to coordinate an increase in domestic and paid labor. We leveraged an existing study of mixed-gender couples with young children assessed prior to the pandemic and conducted pre-registered tests of gender differences in the division and impact of domestic and paid labor as families endured a nationwide COVID-19 lockdown. Although lockdowns offer opportunities for couples to more equally share the domestic load, women did more of the parenting and housework, whereas men generally engaged in more paid work and personal time. Couple members agreed that the balance of labor was unfair on women, but this did not protect women from the detrimental outcomes of a greater domestic burden. Women who were unfairly doing a greater share of housework and parenting, and having less personal time, experienced residual increases in relationship problems and residual decreases in satisfaction.

The inequities in domestic labor and detrimental effects on women’s relationship outcomes occurred irrespective of caregiver or employment status. These results substantiate concerns that the COVID-19 pandemic may have greater risks for women, including quarantine efforts reinforcing gender inequality and placing greater strains on women’s health and wellbeing. Interestingly, exploratory analyses provided tentative evidence that men who were the primary caregiver or not working fulltime also experienced poorer relationship outcomes when they did more of the domestic labor. Thus, generating an equitable division of labor is an important target to protect the health and wellbeing of women (and men) who are shouldering more of the home demands exacerbated by the COVID-19 pandemic and lockdowns.

Couples agree: Women are doing more labor and this division is perceived as unfair

Both women and men reported that women did more housework and parenting, whereas men engaged in more paid work and personal time. The overall pattern of division of housework and parenting is consistent with established gender differences (Bianchi et al., 2000; Kamp Dush et al., 2018; Newkirk et al., 2017) and those reported during the pandemic (Carlson et al., 2020; Craig & Churchill, 2020). Gathering reports from couples, however, clarified that the gender differences typically shown by between-group comparisons of individual reports are evident when comparing women’s and men’s reports within the same relationship. The overall pattern illustrated that, despite home confinement potentially reducing structural barriers to men sharing housework and parenting, both women and men agree that women are shouldering the increased burden of domestic labor arising from COVID-19 lockdowns.

Yet, despite agreeing that gender differences existed, women and men disagreed about the extent of the inequity. Although men reported that women were doing more housework and having less personal time, women reported doing more housework and having less personal time than men’s reports acknowledged. These discrepancies could emerge because housework is less valued than other domains and thus not as visible or fully appreciated. Men may also tend to underestimate the time and energy housework involves due to their lower contribution to this domain, and consequently overestimate the personal time women are afforded or perhaps misinterpret some activities as personal time (e.g., planning, playing with children). It is also possible that women’s greater share of housework and men’s greater share of personal time result in women viewing these inequities as even greater than they are. Importantly, regardless of why disagreement across couples emerged, such disagreement may contribute to the persistence of gender discrepancies in domestic labor. For example, if women’s share of the housework or lack of personal time is not fully appreciated by partners then there is likely less chance that couples will work together to rectify these inequities.

Despite disagreeing about how much more housework and how much less personal time women were engaging compared to men, women and men equally perceived that the relative labor in these domains was unfair. Couples may have more insights into each other’s perceived fairness, perhaps because people are more likely to directly or indirectly communicate their discontent with unfairness. Couples also may consider relative fairness, rather than amount of time and energy spent, when considering each other’s contributions. The prominence of perceived fairness in the evaluation and effects of equity is why perceived fairness tends to have relatively stronger effects on relationship outcomes (Greenstein, 1996). Nonetheless, men’s recognition that the division of domestic labor was more unfair on women did not protect women from the detrimental relationship outcomes associated with a greater domestic burden.

Perceiving inequities as unfair create relationship problems and dissatisfaction for women

Leveraging an existing dyadic study enabled us to uniquely assess how couples’ division of labor predicted residual changes in relationship problems and satisfaction. The pattern of results confirmed that women are more at risk of the negative relationship outcomes associated with perceiving an unfair share of housework, parenting and personal time. With regard to housework, women who reported a more inequitable and unfair division experienced greater problems and lower satisfaction. Applying an equity perspective, tests of the interaction between the relative division and perceived fairness of housework revealed that women who did more housework than their partner and perceived their larger share as unfair experienced the greatest residual increases in relationship problems and reductions in satisfaction.

Perceived unfairness of parenting was also central to how couples’ division of parenting shaped women’s relationship outcomes. Prior cross-sectional studies indicate that inequity and unfairness in the division of parenting is associated with greater conflict and lower satisfaction (Newkirk et al., 2017; Schieman et al., 2018). In the current study, only perceived unfairness in parenting predicted residual changes in problem and satisfaction. A significant interaction also revealed that women who did more parenting than their partner only experienced greater relationship problems when they perceived their share of parenting to be unfair on them. Compared to the onerous necessity of housework, parenting may often be personally fulfilling (Tully et al., 1999) in ways that compensate for a greater burden of the parenting workload. Any compensation of personal fulfilment, however, may not be enough to counter dissatisfaction and problems in the marital relationship when mothers feel their greater contribution is unfair.

Our investigation also extended insight into the relative impact of an unfair division in both domestic and personal activities. First, the impact of gender inequities in domestic labor were not balanced by counter inequities in other domains. Although men on average did more paid work, neither women or men experienced poorer relationship outcomes as a function of a greater or more unfair share of paid work. Instead, women experienced greater problems when their partner perceived their work was unfair, perhaps due to men’s feelings of unfairness creating more relationship difficulties managing expectations around housework, parenting and personal domains. Second, couples agreed that men (on average) had more personal time than women, and men who had relatively more personal time reported lower problems and greater satisfaction. However, couples agreed that women’s lower share of personal time was unfair, and women (but not men) who had less personal time relative to their partner and perceived the share of personal time to be unfair experienced greater relationship problems and lower satisfaction.

Detrimental effects of inequities in domestic labor occur for women regardless of family role, but men who occupy domestic roles may experience similar outcomes as women

More women (50.3%) than men (16.6%) were the primary caregiver, and more men (64.3%) than women (29.9%) worked fulltime. Nonetheless, the gender differences in the division and perceived fairness of parenting, housework and personal time, and the effects of the relative division and fairness of parenting, housework and personal time on women’s relationship outcomes, did not vary across women and men’s caregiver and employment status. Thus, the gendered pattern of the division of labor, and the detrimental effects of the division and perceived fairness of housework and parenting on women’s relationship outcomes, occurred for women in traditional and non-traditional family roles.

Interestingly, however, additional analyses provided some tentative evidence that men may experience poorer relationship outcomes when their family role or situation forces them to pick up more domestic labor. In general, men did not report greater relationship problems or lower relationship satisfaction when they reported doing more housework or parenting or perceived their contributions in these domains were unfair. However, when exploring the moderating role of caregiver and employment status, a small number of consistent effects emerged. Men who were primary caregivers and reported an inequitable division of parenting, and men who were not working fulltime and reported that the division of housework was inequitable or unfair, experienced greater problems and lower satisfaction. This pattern of results indicates that men who take on more of the domestic work and perceive their contribution as unfair experience the same negative relationship outcomes as women.

These novel findings indicate a promising direction for future research by highlighting that the constraints of social roles, in addition to gender, are important for understanding the division and impact of domestic labor (Eagly & Wood, 2016). In particular, the pattern of expected and unexpected effects indicates that prescriptive pressures regarding women’s and men’s social roles result in women experiencing poor outcomes from carrying the burden of domestic labor across social contexts as well as men experiencing negative outcomes when men occupy women’s traditional social role. However, given these unexpected findings for men involved 4 out of 16 interaction effects tested, and the sample composition (16.6% men primary caregivers, 35.7% men not working fulltime) did not provide optimal conditions for these comparisons, future research is needed to more reliably test this intriguing pattern by gathering samples that more evenly represent different family role configurations. Such efforts may also emphasize the primary findings from the current study. Specifically, although these additional findings indicate that poor outcomes may emerge for both women and men who are shouldering more of the domestic labor, women experience more relationship difficulties arising from an unfair division of labor across contexts regardless of family roles.

Caveats and conclusions

Compared to typical large cross-sectional surveys of individuals, our dyadic and longitudinal design provides stronger evidence that an unequal and unfair division labor is likely to increase relationship problems and reduce relationship satisfaction when couples need to be working together to manage the challenges of COVID-19 lockdowns. Dyadic longitudinal designs, however, necessarily restrict sample size and thus statistical power to test for gender differences and interactions. The majority of the effects shown for women were significantly different from the null effects for men, supporting our general conclusions. We also focused on sets of theoretically relevant interactions, but some interaction patterns for relationship problems were relatively weak, likely because problems involve difficulties arising from both individuals’ and partners’ discontent. Finally, our sample involved relatively satisfied couples who agreed that the division was unfair on women. The detrimental outcomes shown here are likely to be magnified in couples who are facing more challenges, report greater discrepancies in the relative division and perceived fairness of labor, and who enter the pandemic and lockdowns with greater relationship difficulties.

Despite these caveats, the results indicate that key challenges of the COVID-19 pandemic are more likely to have detrimental effects on women. Women were more unfairly burdened with domestic labor, and as a consequence were more likely to experience increased relationship problems and dissatisfaction. Accounting for caregiver and employment status revealed that women experienced these poor outcomes across family roles and contexts. The detrimental impact of these inequities is unlikely to be fleeting and may grow as the pandemic and related economic and family disruptions continue across time. Couples who learn to share the load more equitably, however, may protect women from relationship difficulties at a time when satisfying, supportive relationships are crucial for health and wellbeing.

We provide strong evidence for greater male variability in preferences; men are more likely to have extreme time, risk, and social preferences, while women are more likely to have moderate preferences

Converging evidence for greater male variability in time, risk, and social preferences. Christian Thöni and Stefan Volk. Proceedings of the National Academy of Sciences, June 8, 2021 118 (23) e2026112118; https://doi.org/10.1073/pnas.2026112118

Significance: There is continuing interest in the study of gender differences in economic and social outcomes. An important factor underlying gender differences in outcomes are gender differences in fundamental economic preferences, which are at the core of many differential choices of women and men. We provide strong evidence for greater male variability in preferences. We find that men are more likely to have extreme time, risk, and social preferences, while women are more likely to have moderate preferences. With the focus on mean differences, the current literature underestimates the importance of gender differences and their effects on differential choices and outcomes between women and men.

Abstract: Gender differences in time, risk, and social preferences are important determinants of differential choices of men and women, with broad implications for gender-specific social and economic outcomes. To better understand the shape and form of gender differences in preferences, researchers have traditionally examined the mean differences between the two genders. We present an alternative perspective of greater male variability in preferences. In a meta-analysis of experimental economics studies with more than 50,000 individuals in 97 samples, we find converging evidence for greater male variability in time, risk, and social preferences. In some cases, we find greater male variability in addition to mean differences; in some cases, we only find greater male variability. Our findings suggest that theories of gender differences are incomplete if they fail to consider how the complex interaction of between-gender differences and within-gender variability determines differential choices and outcomes between women and men.

Keywords: gendergreater male variabilitypreferencesmeta-analysis

From 2019... Urban spatial order: street network orientation, configuration, and entropy

From 2019... Urban spatial order: street network orientation, configuration, and entropy. Geoff Boeing. Applied Network Science volume 4, Article number: 67. Aug 23 2019. https://appliednetsci.springeropen.com/articles/10.1007/s41109-019-0189-1

Abstract: Street networks may be planned according to clear organizing principles or they may evolve organically through accretion, but their configurations and orientations help define a city’s spatial logic and order. Measures of entropy reveal a city’s streets’ order and disorder. Past studies have explored individual cases of orientation and entropy, but little is known about broader patterns and trends worldwide. This study examines street network orientation, configuration, and entropy in 100 cities around the world using OpenStreetMap data and OSMnx. It measures the entropy of street bearings in weighted and unweighted network models, along with each city’s typical street segment length, average circuity, average node degree, and the network’s proportions of four-way intersections and dead-ends. It also develops a new indicator of orientation-order that quantifies how a city’s street network follows the geometric ordering logic of a single grid. A cluster analysis is performed to explore similarities and differences among these study sites in multiple dimensions. Significant statistical relationships exist between city orientation-order and other indicators of spatial order, including street circuity and measures of connectedness. On average, US/Canadian study sites are far more grid-like than those elsewhere, exhibiting less entropy and circuity. These indicators, taken in concert, help reveal the extent and nuance of the grid. These methods demonstrate automatic, scalable, reproducible tools to empirically measure and visualize city spatial order, illustrating complex urban transportation system patterns and configurations around the world.

Discussion

The urban design historian Spiro Kostof once said: “We ‘read’ form correctly only to the extent that we are familiar with the precise cultural conditions that generated it… The more we know about cultures, about the structure of society in various periods of history in different parts of the world, the better we are able to read their built environment” (Kostof 1991, p. 10). This study does not identify whether or how a city is planned or not. Specific spatial logics cannot be conflated with planning itself, which takes diverse forms and embodies innumerable patterns and complex structures, as do informal settlements and organic urban fabrics. In many cities, centrally planned and self-organized spatial patterns coexist, as the urban form evolves over time or as a city expands to accrete new heterogeneous urban forms through synoecism.

Yet these findings do, in concert, illustrate different urban spatial ordering principles and help explain some nuances of griddedness. For example, gridded Buenos Aires has a φ value suggesting it only follows a single grid to a 15% extent. However, its low circuity and high average node degree values demonstrate how it actually comprises multiple competing grids—which can indeed be seen in Figs. 4 and 5—and it clusters accordingly in Figs. 6 and 7 with gridded American cities. Jointly considered, the φ indicator, average circuity, average node degree, and median street segment length tell us about the extent of griddedness and its character (curvilinear, straight-line, monolithic, heterogeneous, coarse-grained, etc.). Charlotte further illustrates the importance of taking these indicators together. Although its φ and orientation entropy are more similar to European cities’ than American cities’, it is of course an oversimplification to claim that Charlotte is therefore the US city with the most “European” street network—in fact, its median street segment length is about 50% longer than that of the average European city, and among European cities, Charlotte clusters primarily with those of the Communist Bloc. Pittsburgh, on the other hand, sits alone in a small sub-cluster with Munich and Vienna.

We find that cities with higher φ values also tend to have higher node degrees, more four-way intersections, fewer dead-ends, and less-winding street patterns. That is, cities that are more consistently organized according to a grid tend to exhibit greater connectedness and less circuity. Interestingly, the Ηo and Ηw orientation entropies are extremely similar and strongly correlated: the weighted curvatures (versus straight-line orientation) of individual street segments have little impact on citywide orientation entropy, but the average circuity of the city network as a whole positively correlates with orientation entropy. This finding deserves further exploration.

These results also demonstrate substantial regional differences around the world. Across these study sites, US/Canadian cities have an average φ value nearly thirteen-times greater than that of European cities, alongside nearly double the average proportion of four-way intersections. Meanwhile, these European cities’ streets on average are 42% more circuitous than those of the US/Canadian cities. These findings illustrate the differences between North American and European urban patterns. However, likely due to such regional heterogeneity, this study finds statistical relationships somewhat weaker (though still significant) than prior findings examining cities in the UK exclusively.

Accordingly, given the heterogeneity of these world regions, future research can estimate separate statistical models for individual regions or countries—or even the neighborhoods of a single city to draw these findings closer to the scale of planning/design practice. The methods and indicators developed here offer planners and designers a toolbox to quantify urban form patterns and compare their own cities to those elsewhere in the world. Our preliminary results suggest trends and patterns, but future work should introduce additional controls to clarify relationships and make these findings more actionable for researchers and practitioners. For instance, topography likely constrains griddedness and influences circuity and orientation entropy: a study of urban elevation change and hilliness in conjunction with entropy and circuity would help clarify these relationships. Additionally, further research can unpack the relationship between development era, design paradigm, city size, transportation planning objectives, and street network entropy to explore how network growth and evolution affect spatial order. Finally, given the importance of taking multiple indicators in concert, future work can develop a grid-index to unify them and eventually include streetscape and width attributes as further enrichment to explore walkability and travel behavior.

We present the results of a pilot study conducted in Bangladesh which suggests that heightened mortality arising from mother-in-law/daughter-in-law conflict may be a two-way street

In-Law Relationships in Evolutionary Perspective: The Good, the Bad, and the Ugly. Martin Daly, Gretchen Perry. Front. Sociol., June 4 2021. https://doi.org/10.3389/fsoc.2021.683501

Abstract: In-laws (relatives by marriage) are true kin because the descendants that they have in common make them “vehicles” of one another’s inclusive fitness. From this shared interest flows cooperation and mutual valuation: the good side of in-law relationships. But there is also a bad side. Recent theoretical models err when they equate the inclusive fitness value of corresponding pairs of genetic and affinal (marital) relatives-brother and brother-in-law, daughter and daughter-in-law-partly because a genetic relative’s reproduction always replicates ego’s genes whereas reproduction by an affine may not, and partly because of distinct avenues for nepotism. Close genetic relatives compete, often fiercely, over familial property, but the main issues in conflict among marital relatives are different and diverse: fidelity and paternity, divorce and autonomy, and inclinations to invest in distinct natal kindreds. These conflicts can get ugly, even lethal. We present the results of a pilot study conducted in Bangladesh which suggests that heightened mortality arising from mother-in-law/daughter-in-law conflict may be a two-way street, and we urge others to replicate and extend these analyses.

Conclusion

Dow (1984) and Hughes (1988) proposed that affinal “kinship” is no mere metaphor. The commonality of interest among persons related by marriage derives from the same ultimate source as the commonality of interest among persons related by blood. In both cases, the protagonists are “related” by virtue of the fact that they can expect to derive fitness from the same particular reproductive events.

We show, however, that recent theoretical arguments that treat daughters and daughters-in-law (for example) as equivalent contributors to ego’s fitness go too far. “Parallel” pairs of genetic and affinal relationships such as these are importantly different, both quantitatively and qualitatively. Any child of my daughter will be my grandchild, but that is not necessarily true of my daughter-in-law, and even if the latter were to reproduce only with my son, she would retain an interest in natal relatives who are of no relevance to me. The “brute fact” of genetic relatedness (Haig, 2011) favors forgiveness and reconciliation among blood kin, even after betrayals, but a daughter-in-law, unlike a daughter, is replaceable (Voland and Beise, 2005; Mace, 2013). Bride-burnings are committed by mothers-in-law, not by mothers. The oppressive mistreatment of young women by their mothers-in-law, especially in the Indian subcontinent, has been much remarked upon, but we show, in addition, that the destructive effects of this relationship can be a two-way street.

According to Leonetti et al. (2007) “We can speak of “in-law conflict” as an extension of sexual conflict, with parents on both sides joining the fray. Cooperation may also be part of these relationships when the interests of both sides are enhanced. This game, of course, becomes vastly more complicated than the simple struggle between the sexes but is likely to be ancient and of critical importance to human reproductive success.” We concur.

Awareness of lateral posing asymmetries: Although people do not have an acute awareness of their lateral posing preference, they reliably show one side of their faces to express or hide emotions

Do you know your best side? Awareness of lateral posing asymmetries. Matia Okubo & Takato Oyama. Asymmetries of Brain, Behaviour, and Cognition, Jun 4 2021. https://doi.org/10.1080/1357650X.2021.1938105

Abstract: People tend to show the left cheek to broadly express emotions while they tend to show the right cheek to hide emotions because emotions were expressed more on the left than on the right side of the face. The present study investigated the level of awareness on the left- and right-cheek poses using the method of structural knowledge attributions. When asked to broadly express emotions for a family portrait, right-handed participants were more likely to show the left cheek than the right. On the other hand, when asked to conceal emotions to show a calm and reassuring attitude as a scientist, they were more likely to show the right cheek. After the posing session, participants selected the conscious level of their knowledge about posing from five categories: Random, intuition, familiarity, recollection, and rules. Most participants rated their knowledge as unconscious (i.e., either as random, intuition, or familiarity). The choice of the conscious level did not differ across posing orientations and posing instructions. These results suggest that although people do not have an acute awareness of their lateral posing preference, they reliably show one side of their faces to express or hide emotions.

KEYWORDS: Lateral posing asymmetryemotional expressionsawareness

Among liberal countries, inequality was negatively related to subjective well-being for men & women; there was some evidence that the relation was stronger for women; in conservative countries, the relation was not significant

Culture Moderates the Relation Between Gender Inequality and Well-Being. Chen Li, Miron Zuckerman, Ed Diener. Psychological Science, June 1, 2021. https://doi.org/10.1177/0956797620972492

Abstract: Research on the relation of gender inequality and subjective well-being (SWB) has produced inconsistent results. We suggest that culture moderates this relation such that inequality has a greater adverse effect in liberal than in conservative societies. The present studies, using aggregate data from 86 countries (Study 1) and 145,975 individuals’ data from 69 countries (Study 2), support this notion. Among liberal countries, inequality was negatively related to SWB for both men and women; there was some evidence that this relation was stronger for women. In conservative countries, the relation was not significant. Previously, the same liberal–conservative continuum moderated the relation between income inequality and SWB for groups with both high and low socioeconomic status (SES) but particularly for the low-SES group. The similarity in results across two different studies strongly supports the notion that the relation between inequality and SWB is contingent on where specific cultures are located on the liberal–conservative continuum.

Keywords: culture, gender inequality, subjective well-being

Breeding season length (bsl) & mating system are the strongest predictors of testosterone concentrations; bsl, environmental temperature, & variability in precipitation are the strongest predictors of within-population variation in test.

Life history and environment predict variation in testosterone across vertebrates. Jerry F. Husak et al. Evolution, March 23 2021. https://doi.org/10.1111/evo.14216

Abstract: Endocrine systems act as key intermediaries between organisms and their environments. This interaction leads to high variability in hormone levels, but we know little about the ecological factors that influence this variation within and across major vertebrate groups. We study this topic by assessing how various social and environmental dynamics influence testosterone levels across the entire vertebrate tree of life. Our analyses show that breeding season length and mating system are the strongest predictors of average testosterone concentrations, whereas breeding season length, environmental temperature, and variability in precipitation are the strongest predictors of within-population variation in testosterone. Principles from small-scale comparative studies that stress the importance of mating opportunity and competition on the evolution of species differences in testosterone levels, therefore, likely apply to the entire vertebrate lineage. Meanwhile, climatic factors associated with rainfall and ambient temperature appear to influence variability in plasma testosterone, within a given species. These results, therefore, reveal how unique suites of ecological factors differentially explain scales of variation in circulating testosterone across mammals, birds, reptiles, amphibians, and fishes.

Breeding season length (bsl) & mating system are the strongest predictors of testosterone concentrations; bsl, environmental temperature, & variability in precipitation are the strongest predictors of within-population variation in test.

Rolf Degen summarizing... The sources of information by which people were most often exposed to politically dissimilar news were search engines and social media, once again giving the lie to the condescending notion of "echo chambers"

Avenues to News and Diverse News Exposure Online: Comparing Direct Navigation, Social Media, News Aggregators, Search Queries, and Article Hyperlinks. Magdalena Wojcieszak. The International Journal of Press/Politics, May 31, 2021. https://doi.org/10.1177/19401612211009160

Abstract: The online environment dramatically expands the number of ways people can encounter news but there remain questions of whether these abundant opportunities facilitate news exposure diversity. This project examines key questions regarding how internet users arrive at news and what kinds of news they encounter. We account for a multiplicity of avenues to news online, some of which have never been analyzed: (1) direct access to news websites, (2) social networks, (3) news aggregators, (4) search engines, (5) webmail, and (6) hyperlinks in news. We examine the extent to which each avenue promotes news exposure and also exposes users to news sources that are left leaning, right leaning, and centrist. When combined with information on individual political leanings, we show the extent of dissimilar, centrist, or congenial exposure resulting from each avenue. We rely on web browsing history records from 636 social media users in the US paired with survey self-reports, a unique data set that allows us to examine both aggregate and individual-level exposure. Visits to news websites account for about 2 percent of the total number of visits to URLs and are unevenly distributed among users. The most widespread ways of accessing news are search engines and social media platforms (and hyperlinks within news sites once people arrive at news). The two former avenues also increase dissimilar news exposure, compared to accessing news directly, yet direct news access drives the highest proportion of centrist exposure.

Keywords: news exposure, avenues for news, social networks, search engines, cross-cutting exposure, echo chambers

Insufficiently Complimentary?: Underestimating the Positive Impact of Compliments Creates a Barrier to Expressing Them

Zhao, Xuan, and Nicholas Epley. 2021. “Insufficiently Complimentary?: Underestimating the Positive Impact of Compliments Creates a Barrier to Expressing Them.” PsyArXiv. June 4. doi:10.1037/pspa0000277

Abstract: Compliments increase the well-being of both expressers and recipients, yet people report in a series of surveys giving fewer compliments than they should give, or would like to give. Nine experiments suggest that a reluctance to express genuine compliments partly stems from underestimating the positive impact that compliments will have on recipients. Participants wrote genuine compliments and then predicted how happy and awkward those compliments would make recipients feel. Expressers consistently underestimated how positive the recipients would feel but overestimated how awkward recipients would feel (Experiments 1-3, S4). These miscalibrated expectations are driven partly by perspective gaps in which expressers underestimate how competent—and to a lesser extent how warm—their compliments will be perceived by recipients (Experiments 1-3). Because people’s interest in expressing a compliment is partly driven by their expectations of the recipient’s reaction, undervaluing a compliment creates a barrier to expressing them (Supplemental Experiments S2, S3, S4). As a result, directing people to focus on the warmth conveyed by their compliment (Experiment 4) increased interest in expressing it. We believe these findings may reflect a more general tendency for people to underestimate the positive impact of prosocial actions on others, leading people to be less prosocial than would be optimal for both their own and others’ well-being.

The share of participants willing to be vaccinated increased with the payment amount; a significant change required large rewards of €3,250 or more

Sprengholz, Philipp, Luca Henkel, and Cornelia Betsch. 2021. “Payments and Freedoms: Effects of Monetary and Legal Incentives on COVID-19 Vaccination Intentions in Germany.” PsyArXiv. June 4. doi:10.31234/osf.io/hfm43

Abstract: Monetary and legal incentives have been proposed to promote COVID-19 vaccination uptake. To evaluate the suitability of incentives, an experiment with German participants examined the effects of payments (varied within subjects: 0 to 10,000 EUR) and freedoms (varied between subjects: vaccination leading vs. not leading to the same benefits as a negative test result) on the vaccination intentions of previously unvaccinated individuals (n = 782). While no effect could be found for freedoms, the share of participants willing to be vaccinated increased with the payment amount. However, a significant change required large rewards of 3,250 EUR or more. While monetary incentives could increase vaccination uptake by a few percentage points, the high costs of implementation challenge the efficiency of the measure and call for alternatives. As experimental data suggest that considering vaccination as safe, necessary, and prosocial increases an individual’s likelihood of wanting to get vaccinated without payment, educational campaigns should emphasize these features when promoting vaccination against COVID-19.

Romantic Partners Are Similar in Their Well-Being and Sociopolitical Attitudes but Change Independently Over Time

Romantic Partners Are Similar in Their Well-Being and Sociopolitical Attitudes but Change Independently Over Time. Matthew D. Hammond, Chris G. Sibley. Social Psychological and Personality Science, June 3, 2021. https://doi.org/10.1177/19485506211019843

Abstract: Similarity within romantic couples forms one component of the formation and maintenance of relationships, meaning that, romantic partners’ views about themselves and the world are theorized to converge over time. We advance prior research on romantic couple similarities using cross-sectional or time-lagged designs, testing convergence with dyadic trajectories of change—how changes in one person relate to changes in their partner. Dyadic growth curve models assessed initial similarities, and longitudinal convergence, for 35 measures of well-being and individual differences in 171 mixed-gender couples from a national longitudinal study (the New Zealand Attitudes and Values Survey). Results indicated consistent average-level similarities between romantic partners, a few instances of short-term convergence in sociopolitical views, and the consistent pattern that changes in people occurred independently to their partners. Findings advance theory on romantic interdependence by emphasizing the perspective that romantic partners’ convergence occurs as subjective experience rather than externally measured unification.

Keywords: romantic relationships, interdependence, matching, alignment, shared reality

Those with simple number systems (an upper limit not much higher than ‘four’) often had few material possessions, such as weapons, tools or jewellery; those with elaborate systems always had a richer array of possessions

How did Neanderthals and other ancient humans learn to count? Colin Barras. Nature 594, 22-25, Jun 2 2021. https://www.nature.com/articles/d41586-021-01429-6

Archaeological finds suggest that people developed numbers tens of thousands of years ago. Scholars are now exploring the first detailed hypotheses about this life-changing invention.

Counting on possessions

In a 2013 study11, Overmann analysed anthropological data relating to 33 contemporary hunter-gatherer societies across the world. She discovered that those with simple number systems (an upper limit not much higher than ‘four’) often had few material possessions, such as weapons, tools or jewellery. Those with elaborate systems (an upper numeral limit much higher than ‘four’) always had a richer array of possessions. The evidence suggested to Overmann that societies might need a variety of material possessions if they are to develop such number systems.

In societies with complex number systems, there were clues to how those systems developed. Significantly, Overmann noted that it was common for these societies to use quinary (base 5), decimal or vigesimal (base 20) systems. This suggested to her that many number systems began with a finger-counting stage.

This finger-counting stage is important, according to Overmann. She is an advocate of material engagement theory (MET), a framework devised about a decade ago by cognitive archaeologist Lambros Malafouris at the University of Oxford, UK12. MET maintains that the mind extends beyond the brain and into objects, such as tools or even a person’s fingers. This extension allows ideas to be realized in physical form; so, in the case of counting, MET suggests that the mental conceptualization of numbers can include the fingers. That makes numbers more tangible and easier to add or subtract.

The societies that moved beyond finger-counting did so, argues Overmann, because they developed a clearer social need for numbers. Perhaps most obviously, a society with more material possessions has a greater need to count (and to count much higher than ‘four’) to keep track of objects.

Overmann thinks MET implies that there is another way in which material possessions are necessary for the elaboration of number systems. An artefact such as a tally stick also becomes an extension of the mind, and the act of marking tally notches on the stick helps to anchor and stabilize numbers as someone counts. These aids could have been crucial to the process through which humans first began counting up to large numbers13.

Eventually, says Overmann, some societies moved beyond tally sticks. This first happened in Mesopotamia around the time when cities emerged there, creating an even greater need for numbers to keep track of resources and people. Archaeological evidence suggests that by 5,500 years ago, some Mesopotamians had begun using small clay tokens as counting aids.

[photo]

According to Overmann, MET suggests that these tokens were also extensions of the mind, and that they fostered the emergence of new numerical properties. In particular, the shapes of tokens came to represent different values: 10 small cone tokens were equivalent to a sphere token, and 6 spheres were equivalent to a large cone token. The existence of large cones, each equivalent to 60 small cones, allowed the Mesopotamians to count into the thousands using relatively few tokens.

Andrea Bender, a psychologist at the University of Bergen in Norway and another leader of the QUANTA project, says that the team members plan to gather and analyse large amounts of data relating to the world’s numeral systems. That should allow them to test Overmann’s hypothesis that body parts and artefacts might have helped societies to develop number systems that ultimately count into the thousands and higher. But Bender says she and her colleagues are not presupposing that Overmann’s MET-based ideas are correct.

Others are more enthusiastic. Karim Zahidi, a philosopher at the University of Antwerp in Belgium, says that although Overmann’s scenario is still incomplete, it has real potential to explain the development of the elaborate number systems in use today.

Linguistic leads

Overmann acknowledges that her hypothesis is silent on one issue: when in prehistory human societies began developing number systems. Linguistics might offer some help here. One line of evidence suggests that number words could have a history stretching back at least tens of thousands of years.

Evolutionary biologist Mark Pagel at the University of Reading, UK, and his colleagues have spent many years exploring the history of words in extant language families, with the aid of computational tools that they initially developed to study biological evolution. Essentially, words are treated as entities that either remain stable or are outcompeted and replaced as languages spread and diversify. For instance, English ‘water’ and German ‘wasser’ are clearly related, making them cognates that derive from the same ancient word — an example of stability. But English ‘hand’ is distinct from Spanish ‘mano’ — evidence of word replacement at some time in the past. By assessing how frequently such replacement events occur over long periods, it is possible to estimate rates of change and to infer how old words are.

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Using this approach, Pagel and Andrew Meade at Reading showed that low-value number words (‘one’ to ‘five’) are among the most stable features of spoken languages14. Indeed, they change so infrequently across language families — such as the Indo-European family, which includes many modern European and southern Asian languages — that they seem to have been stable for anywhere between 10,000 and 100,000 years.

This doesn’t prove that the numbers from ‘one’ to ‘five’ derive from ancient cognates that were first spoken tens of thousands of years ago, but Pagel says it’s at least “conceivable” that a modern and a Palaeolithic Eurasian could have understood one another when it came to such number words.

Pagel’s work has its fans, including Gray, another of QUANTA’s leaders, but his claims are challenged by some scholars of ancient languages. Don Ringe, a historical linguist at the University of Pennsylvania in Philadelphia, says it isn’t clear that the stability of lower-number words can just be projected far back into prehistory, regardless of how stable they seem to be in recent millennia.

That all adds up to a slew of open questions about when and how humans first started using numbers. But despite the debate swirling around these questions, researchers agree it’s a topic that deserves a lot more attention. “Numbers are just so fundamental to everything we do,” says Gray. “It’s hard to conceive of human life without them.”

Numbers might even have gained this importance deep in prehistory. The notched baboon bone from Border Cave is worn smooth in a way that indicates that ancient humans used it over many years. “It was clearly an important item for the individual who produced it,” says D’Errico.

Not so for the Les Pradelles specimen, which lacks this smooth surface. If it does record numerical information, that might not have been quite as important at the time. In fact, although D’Errico and his colleagues have spent innumerable hours analysing the bone, he says it’s possible that the Neanderthal who chipped away at that hyena femur some 60,000 years ago spent very little time using it before tossing the bone aside.

Based on a panel between 1980 & 2016, I find that one more Sunday with precipitation at the time of church increases yearly drug-related, alcohol-related & white-collar crimes, but not for violent or property crimes

Sinning in the Rain: Weather Shocks, Church Attendance and Crime. Jonathan Moreno-Medina. The Review of Economics and Statistics 1–46. Mar 17 2021. https://doi.org/10.1162/rest_a_01024

Abstract: This paper provides evidence of the causal effect of church attendance on petty crime by using quasi-random variation in the number of Sundays when it precipitated at the specific time of most religious services. Using a novel strategy, I find a narrow time window when most individuals attend church. Based on a panel between 1980 and 2016, I find that one more Sunday with precipitation at the time of church increases yearly drug-related, alcohol-related and white-collar crimes. I do not find an effect for violent or property crimes. These effects are driven by more religious counties. Previous evidence showing negative effects of church attendance on the demand for alcohol and drugs is consistent with a demand-driven interpretation of the results presented.

Keywords: economics of religion, religious attendance, crime, social norms

JEL: Z12, D74, K14, J24, O17, H80

7 Conclusions

A large body of literature has discussed the relationship between church attendance, religion, and crime. While some individuals have stated that religion represents the moral bedrock of society, with church attendance being an important part in the communication of these moral values, others have argued for the divisive nature of religion and the possibility that it creates out-group conflict. Although this debate has permeated the criminology and sociology liter^Bature, to my knowledge no document has established a credible causal link between church attendance and crime. This paper attempts to fill in this gap by exploiting the precipitation level at the time of church.

The results suggest that church attendance reduces the prevalence of substance-related crimes and white-collar crimes. At the same time, there is a lack of evidence supporting the notion that church attendance alleviates serious crimes, such as murder, robbery or rape. Burkett & White (1974) hypothesized that studies evaluating the impact of religion on crime would find a higher effect for victimless and ascetic crimes (drug and alcohol use) than for violent and property crimes (theft and murder). This is because, for the latter category of crimes, a series of secular institutions work in parallel to decrease them, while for victimless crimes, religious institutions act in relative isolation. Although it is debatable if drug and alcohol-related crimes are victimless or not, the results of this document provide some support to the aforementioned hypothesis.

More research is needed to disentangle the mechanisms driving these results. Some of the most plausible mechanisms include beliefs, social capital and saliency. Lastly, the welfare implications of these changes in church attendance are not clear. Even more so, considering the zero-estimated effects of this paper as well.

Emotions and temperature are closely related through embodied processes, and people seem to associate temperature concepts with emotions

Barbosa Escobar F, Velasco C, Motoki K, Byrne DV, Wang QJ (2021) The temperature of emotions. PLoS ONE 16(6): e0252408, Jun 3 2021. https://doi.org/10.1371/journal.pone.0252408

valance >>> valence

Abstract: Emotions and temperature are closely related through embodied processes, and people seem to associate temperature concepts with emotions. While this relationship is often evidenced by everyday language (e.g., cold and warm feelings), what remains missing to date is a systematic study that holistically analyzes how and why people associate specific temperatures with emotions. The present research aimed to investigate the associations between temperature concepts and emotion adjectives on both explicit and implicit levels. In Experiment 1, we evaluated explicit associations between twelve pairs of emotion adjectives derived from the circumplex model of affect, and five different temperature concepts ranging from 0°C to 40°C, based on responses from 403 native speakers of four different languages (English, Spanish, Japanese, Chinese). The results of Experiment 1 revealed that, across languages, the temperatures were associated with different regions of the circumplex model. The 0°C and 10°C were associated with negative-valanced, low-arousal emotions, while 20°C was associated with positive-valanced, low-to-medium-arousal emotions. Moreover, 30°C was associated with positive-valanced, high-arousal emotions; and 40°C was associated with high-arousal and either positive- or negative-valanced emotions. In Experiment 2 (N = 102), we explored whether these temperature-emotion associations were also present at the implicit level, by conducting Implicit Association Tests (IATs) with temperature words (cold and hot) and opposing pairs of emotional adjectives for each dimension of valence (Unhappy/Dissatisfied vs. Happy/Satisfied) and arousal (Passive/Quiet vs. Active/Alert) on native English speakers. The results of Experiment 2 revealed that participants held implicit associations between the word hot and positive-valanced and high-arousal emotions. Additionally, the word cold was associated with negative-valanced and low-arousal emotions. These findings provide evidence for the existence of temperature-emotion associations at both explicit and implicit levels across languages.

General discussion

In the present study, we aimed to uncover how people associate a range of adjectives spanning the emotional circumplex model with different temperature concepts. To this end, we conducted two experiments. In Experiment 1, we evaluated the explicit associations between twelve different emotion adjectives, varying in valence and arousal, and five different temperature concepts on native speakers of four different languages (English, Spanish, Japanese, and Chinese). In Experiment 2, we evaluated native English speakers in terms of their implicit associations between temperature words (hot and cold) and emotion adjectives at the opposite ends of both the valence (Unhappy/Dissatisfied and Happy/Satisfied) and the arousal (Passive/Quiet and Active/Alert) dimensions.

Altogether, the results provided evidence for the existence of explicit and implicit associations between emotions adjectives and temperature concepts. The results of Experiment 1 showed that, regardless of language, the peak of the association ratings moved counterclockwise in the canonical circumplex model of core affect from the lower left side (third quadrant) to the upper left side (second quadrant) as temperature increased from 0°C to 40°C. The results of the IATs in Experiment 2 revealed that participants had faster response times when the word hot was independently matched with the positive-valence and the high-arousal emotion words, than when these emotion words were matched with the word cold. Furthermore, as evidenced by the magnitude of the D values, the associations in the arousal dimension were stronger than in the valence dimension, potentially due to a more linear relationship between temperature and arousal, compared to valance. Therefore, consistent with Experiment 1, the results of Experiment 2 revealed that participants implicitly associated the word cold with the low arousal emotion and the word hot with the high arousal emotion. While some studies have hinted at the existence of temperature-emotion associations, to the best of our knowledge, this is the first study to uncover associations between them explicitly and implicitly and explore their similarity across languages.

Our results may be interpreted from the theory of grounded cognition [51, 53]. It is possible that the associations uncovered here arise from the multimodal representations encoded in the brain incorporating the temperature (body or ambient) experienced during specific emotional states repeated. For instance, the robust associations of 20°C with positive valence, low arousal emotions can be a product of the physical comfort this temperature generates for most people. It is also possible that the associations between emotions and temperature arose because there is causal relationship between them, whether it is in the case where emotions trigger physiological responses that affect bodily temperature [92], or in the case where ambient temperatures trigger affective states [17].

The results of Experiment 1 showed that there was a positive relationship between temperature concepts and the arousal dimension of the emotions. In line with our hypotheses, the results also revealed an inverted U-shaped relationship between temperature concepts and valence since the extreme temperature concepts, both cold and hot, were associated with negatively valanced emotions, whereas the milder ambient temperature was associated with positive valanced emotions. A possibility is that valence is related to embodied process of comfort as warmer temperatures are comfortable but extreme temperatures at both ends can generate discomfort [47]. These results are consistent with Wilkowski et al. [93] as the authors suggested people from different cultures use metaphorical expressions of hot and negative emotions (e.g., anger). These results also are also in line with Baylis et al. [62], who found that expressions of positive emotions in social media were the highest at 20°C and decreased beyond 30°C, at which point negative emotions also increased. It is worth noting that the present study did not control for whether participants interpreted the temperature concepts presented as coming from the environment or from a specific object, despite the visual representations used. Hence the temperature range considered comfortable might differ. The results of Experiment 2 were partially consistent with studies that have implied that warmer temperatures are positively valanced [17, 59, 60]. It is important to note that only two temperature words were used. Experiment 2 also revealed that the association between temperature and arousal was more robust than that between temperature and valence, potentially because associations with valence at higher temperatures is less clear as hotter temperatures can be evaluated positively or negatively, as Experiment 1 showed.

Furthermore, people may associate high arousal emotions, whether they are positively or negatively valanced, with higher temperatures because body temperature increases when they experience those emotions. Some studies that have shown that the temperature of peripheral body regions decreases during negative-valanced, high-arousal emotional states [31, 67, 94, 95]. Nevertheless, other studies have indicated that body temperature changes which are triggered by emotions generally accompany arousal, but are independent of the valence of the emotions [92, 96], which seems to be consistent with the associations of the higher temperature concepts in Experiment 1 and the smaller difference across dimensions of Experiment 2. Examining the inverse relationship between temperature and emotions, in which certain temperatures trigger specific emotional states, the associations can come from high ambient temperatures or activities that increase body temperature and hence arousal. For example, physical exercise increases body temperature and at the same time may increase excitement and energy levels. Similarly, it is possible that the associations between positive emotions with low levels of arousal and ambient temperatures arise because at this temperature, people are at their homeostatic optimum [1, 12, 30] and therefore feel calm, secure, or happy.

The results of Experiment 1 showed that the associations across the four languages exhibited a high degree of similarity and followed the same overall direction towards the two dimensions of the emotions. These findings are consistent with other studies that have found large similarities in associations between emotions and colors [49, 82, 97, 98] and emotions and brightness [99] across languages. The large similarity in temperature-emotion associations can be the result of highly comparable concepts linked to emotions across languages, which can potentially be captured by broad categories. As Ogarkova [37] suggested, emotional categories in most languages have similar hierarchical structures and the variance of emotion lexicons can be explained by a few relevant dimensions. Another potential explanation of these results is that the subjective experience of emotions did not differ significantly across speakers of the various languages. It is possible that the emotion-temperature associations are fundamentally driven by core affect, which according to the constructionist theory of emotion, is parsed into specific emotion categories [24, 100]. As Sievers et al. [101] suggested, there is a high degree of similarity in how people understand expressions of emotional arousal since they are signaled with a multisensory code based on variations in magnitude. Our findings agree with Jackson et al. [27] in that they seem to reflect the existence of a common semantic framework of emotions across language based on valence and arousal, which are linked to neurophysiological systems that keep homeostasis, although there exists cultural differences.

Despite the high degree of similarity in the emotion-temperature associations across languages, small differences were present. These differences may arise because of linguistic discrepancies and what the various emotions mean in across languages, as well as countries [27]. As Lindquist [36] suggested, languages encode emotions differently, and emotional perception is culturally relative. Additionally, these differences may be caused by environmental factors and the degree of exposure native speakers of a given language that predominantly live-in specific countries have with different temperature ranges. For example, Jonauskaite et al. [49] found that the association between yellow and the concept of joy varied depending on overall exposure to sunshine. Temperature may affect the expression of affect, as well as the subjective experience of similarly intense affective stimuli [12].

Regarding the lower temperature associations for high-arousal emotions in Chinese-speaking participants, it is possible that these differences are the result of a restrained view of the experience and reporting of intense emotions [102]. Intriguingly, there was a slightly higher correlation in the associations between Chinese- and Spanish-speaking participants compared to that between Chinese- and Japanese-speaking participants, as based on geographical and linguistic distance, the latter should be higher [103]. It is possible that this was caused by a greater international cultural exposure from both language groups. However, further research is needed to strip out the effect behind these differences.

Limitations and future directions

One of the main limitations of the present work relates to the set of emotions used. While we focused on emotions that derived from the valence and arousal dimensions, the pool of emotions that can be studied is virtually endless, and other emotions that could have associations with temperature were not included. For instance, romantic or sensual emotions were not analyzed. Future studies may focus on associations with a much more precise set of emotions that have greater relevance for specific fields or applications. That said, the emotion adjectives [70] have been validated across cultures in 23 consumer studies (each with 104–270 participants) involving New Zealand and Chinese consumers. The adjectives were also validated with different types of stimuli (i.e., text, images, aromas, and taste). The emotion circumplex covers a wide range of relevant emotions while remaining parsimonious and is applicable to extensive classes of stimuli. Another aspect to consider when applying these temperature-emotion associations in real world scenarios, is that both temperature and emotions can be product- or context-specific. For instance, while companies may want to generate associations between refreshing beverages and positive emotions, using warm temperatures associations would not be ideal.

Another limitation comes from the method in which the temperatures were presented (visual representations in Experiment 1 and temperature words in Experiment 2). Since no actual temperatures were used, it is not possible to rule out potential semantic effects. People could have also interpreted emotion or temperature words differently, thus introducing some variability. In Experiment 1, people from different countries may not be equally used to certain temperatures. in Experiment 2, people could have had considered diverse temperature ranges for the words hot and cold. Nevertheless, the results provide considerable confidence since the experiment captured relative differences given its within-subjects design. The five temperatures and their visual representations (along with the specific values in°C and°F) in Experiment 1 were chosen as way to cover a broad range of the ambient temperature spectrum, reduce potential language biases, and increase familiarity with temperature measurements. However, it is not certain that participants thought about ambient temperature with these representations. Future studies could expand the range of temperatures and represent them in different ways so that the meaning of temperature is less ambiguous. Moreover, exploring potential differences in the associations between emotions and environmental and object-based temperatures could generate interesting insights. For instance, similar versions of IATs could be designed using pictures of objects or scenes evoking different temperatures combined with facial expressions, such as emojis. Another limitation, especially in the IATs, comes from the possibility that, when evaluating the emotion-temperature associations explicitly or pressing a key in the IAT, participants may not have read the entirety of the pairs of emotion words but instead relied only on the first word. That being said, the use of these emotion adjectives has been extensively validated in multiple studies [70–72].

In recent years, the interest in crossmodal correspondences has seen a rapid growth from academics and practitioners. Research on these correspondences has found a myriad of associations between different modalities (see [104]), and temperature-based correspondences has recently regained the interest of researchers relates to temperature [105, 106]. Spence [107] has recently reviewed the literature on temperature-related crossmodal correspondences. The present study provides valuable insights to advance the study of crossmodal correspondences since the explicit and implicit associations found here may help deepen the understanding of temperature-based crossmodal correspondences mediated by emotions and the role language might play in them. More specifically, these results can guide future studies on the mechanisms behind temperature-based crossmodal correspondences.

To conclude, our findings provide evidence of the existence of consistent associations between emotions and temperature concepts at the explicit level across languages. The findings also provide evidence that some explicit associations also translate to the implicit level. The present study also adds to the literature on emotions and their associations with abstract concepts, and to research on the bidirectionally causal embodied processes between emotions and temperature. Furthermore, the present article contributes to the discussion of how conceptual metaphors can help people understand abstract concepts by interpreting them in terms of concrete experiences, and how using these metaphors can change both how people view the world and their subsequent behavior.

Similar to humans, Eurasian jays are susceptible to magic effects that utilize fast movements, but unlike us, they do not appear to be misled by magic effects that rely on the observer’s intrinsic expectations in human object manipulation

Exploring the perceptual inabilities of Eurasian jays (Garrulus glandarius) using magic effects. Elias Garcia-Pelegrin, Alexandra K. Schnell, Clive Wilkins, and Nicola S. Clayton. Proceedings of the National Academy of Sciences, June 15, 2021 118 (24) e2026106118; https://doi.org/10.1073/pnas.2026106118

Significance: While we know that humans are often deceived by magic effects, little is known concerning how nonhuman animals perceive these intricate techniques of deception. Here, we tested the susceptibility to be misled by three different magic effects on a sample of six Eurasian jays (Garrulus glandarius). We demonstrate that, similar to humans, Eurasian jays are susceptible to magic effects that utilize fast movements. However, unlike humans, Eurasian jays do not appear to be misled by magic effects that rely on the observer’s intrinsic expectations in human object manipulation. Magic effects can provide an insightful methodology to investigate perception and attentional shortcomings in human and nonhuman animals and offer unique opportunities to highlight cognitive constraints in diverse animal minds.

Abstract: In recent years, scientists have begun to use magic effects to investigate the blind spots in our attention and perception [G. Kuhn, Experiencing the Impossible: The Science of Magic (2019); S. Macknik, S. Martinez-Conde, S. Blakeslee, Sleights of Mind: What the Neuroscience of Magic Reveals about Our Everyday Deceptions (2010)]. Recently, we suggested that similar techniques could be transferred to nonhuman animal observers and that such an endeavor would provide insight into the inherent commonalities and discrepancies in attention and perception in human and nonhuman animals [E. Garcia-Pelegrin, A. K. Schnell, C. Wilkins, N. S. Clayton, Science 369, 1424–1426 (2020)]. Here, we performed three different magic effects (palming, French drop, and fast pass) to a sample of six Eurasian jays (Garrulus glandarius). These magic effects were specifically chosen as they utilize different cues and expectations that mislead the spectator into thinking one object has or has not been transferred from one hand to the other. Results from palming and French drop experiments suggest that Eurasian jays have different expectations from humans when observing some of these effects. Specifically, Eurasian jays were not deceived by effects that required them to expect an object to move between hands when observing human hand manipulations. However, similar to humans, Eurasian jays were misled by magic effects that utilize fast movements as a deceptive action. This study investigates how another taxon perceives the magician’s techniques of deception that commonly deceive humans.

Keywords: magicperceptionattentioncomparative cognitioncorvids

Popular version: Magic Tricks May Fool You, but These Birds Can See Through Them - The New York Times

Observed significant increases in frequencies of alleles of more body fat in females contradicts hypotheses that sex differences have adaptively decreased following subsistence transitions from hunting & gather'g to agric

Arner AM, Grogan KE, Grabowski M, Reyes-Centeno H, Perry GH (2021) Patterns of recent natural selection on genetic loci associated with sexually differentiated human body size and shape phenotypes. PLoS Genet 17(6): e1009562, Jun 3 2021. https://doi.org/10.1371/journal.pgen.1009562

Abstract: Levels of sex differences for human body size and shape phenotypes are hypothesized to have adaptively reduced following the agricultural transition as part of an evolutionary response to relatively more equal divisions of labor and new technology adoption. In this study, we tested this hypothesis by studying genetic variants associated with five sexually differentiated human phenotypes: height, body mass, hip circumference, body fat percentage, and waist circumference. We first analyzed genome-wide association (GWAS) results for UK Biobank individuals (~194,000 females and ~167,000 males) to identify a total of 114,199 single nucleotide polymorphisms (SNPs) significantly associated with at least one of the studied phenotypes in females, males, or both sexes (P<5x10-8). From these loci we then identified 3,016 SNPs (2.6%) with significant differences in the strength of association between the female- and male-specific GWAS results at a low false-discovery rate (FDR<0.001). Genes with known roles in sexual differentiation are significantly enriched for co-localization with one or more of these SNPs versus SNPs associated with the phenotypes generally but not with sex differences (2.73-fold enrichment; permutation test; P = 0.0041). We also confirmed that the identified variants are disproportionately associated with greater phenotype effect sizes in the sex with the stronger association value. We then used the singleton density score statistic, which quantifies recent (within the last ~3,000 years; post-agriculture adoption in Britain) changes in the frequencies of alleles underlying polygenic traits, to identify a signature of recent positive selection on alleles associated with greater body fat percentage in females (permutation test; P = 0.0038; FDR = 0.0380), directionally opposite to that predicted by the sex differences reduction hypothesis. Otherwise, we found no evidence of positive selection for sex difference-associated alleles for any other trait. Overall, our results challenge the longstanding hypothesis that sex differences adaptively decreased following subsistence transitions from hunting and gathering to agriculture.

Author summary: There is uncertainty regarding the evolutionary history of human sex differences for quantitative body size and shape phenotypes. In this study we identified thousands of genetic loci that differentially impact body size and shape trait variation between females and males using a large sample of UK Biobank individuals. After confirming the biological plausibility of these loci, we used a population genomics approach to study the recent (over the past ~3,000 years) evolutionary histories of these loci in this population. We observed significant increases in the frequencies of alleles associated with greater body fat percentage in females. This result is contradictory to longstanding hypotheses that sex differences have adaptively decreased following subsistence transitions from hunting and gathering to agriculture.

Discussion

Using a sex-stratified GWAS framework for five sexually differentiated anthropometric phenotypes, we identified 3,016 SNPs that were disproportionately associated with either female or male trait variation at a low false discovery rate (FDR<0.001). We confirmed the biological plausibility of these results by showing that genes with known roles in sexual differentiation are significantly enriched for SexDiff-associated SNPs. Together, these results confirm the importance of considering sex differences when investigating the genetic structure of human polygenic traits [43]. We then used a statistic that quantifies changes in the frequencies of alleles underlying polygenic traits over the past ~3,000 years to identify a signature of recent positive selection on SNPs associated with increased female body fat percentage in the British study population.

We must emphasize that inferring selection signals from GWAS data should be approached with great care, as even subtle uncorrected population structure can impact GWAS and downstream results [44]. For example, data from the GIANT consortium were previously used to identify strong signatures of polygenic selection for height across the genome [20]. However, subtle population structure in the GIANT sample led to effect-size estimate biases, in turn resulting in false signals of polygenic selection for SNPs not crossing the genome-wide significance threshold and impacting results for significant SNPs as well [44]. In contrast, these issues were much less prevalent using GWAS summary statistics from the UK Biobank, in which population structure is minimized [44–46]. In light of these considerations, in our study we have i) used UK Biobank GWAS summary statistics only, ii) focused solely on phenotype-associated SNPs below the genome-wide significance threshold, and iii) restricted our evolutionary analyses to direct comparisons between SNPs significantly associated with individual phenotypes and a sub-phenotype (i.e., sex differences).

Our study further demonstrates the value of GWAS-based approaches for testing anthropological hypotheses [47]. Concerning the evolution of human body size and shape phenotypes, our results fail to provide support for the prevailing notion of recent (i.e., subsequent to agriculture) adaptive reductions in levels of sex differences for such traits. Specifically, using large samples of genomes from British individuals we did not observe significant differences in the recent evolutionary trajectories of SNPs disproportionately associated with female or male variation in height, body mass, hip circumference, and waist circumference relative to the trajectories of SNPs associated with these traits generally.

We note that we made a number of conservative choices (for example, with aggressive pruning to account for linkage disequilibrium) in our analytical approach, meaning that our failure to reject the null hypothesis for each of these four traits should not be interpreted as evidence that no selection on them occurred. Still, even with our conservative analytical approach we did find evidence that the average frequencies of alleles disproportionately associated with greater female body fat percentage significantly increased over the past ~3,000 years, a pattern consistent with polygenic adaptation. Given that females have higher average body fat percentages than men in historic and contemporary populations, the direction of polygenic adaptation in the population we studied would actually be opposite to expectations under hypotheses of recent adaptive reductions in anthropometric trait sex differences in agricultural societies. However, since SNPs can be pleiotropically associated with multiple phenotypes [35], we cannot definitively conclude that positive selection acted directly on female body fat percentage. Regardless, at the very least we did not find positive support for the prevailing hypothesis concerning the evolution of sex differences in recent human evolution.