The prosociality of married people: Evidence from a large multinational sample.

Single people are more likely to die from COVID-19. Here we study whether this higher death rate could be partly explained by differences in compliance with protective health measures against COVID-19 between single and married people, and the drivers of this marital compliance gap. Data collected from 46,450 respondents in 67 countries reveal that married people are more likely to comply with protective measures than single people.

The smell of cooperativeness: Do human body odours advertise cooperative behaviours?

Several physical features influence the perception of how cooperative a potential partner is. While previous work focused on face and voice, it remains unknown whether body odours influence judgements of cooperativeness and if odour-based judgements are accurate. Here, we first collected axillary odours of cooperative and uncooperative male donors through a public good game and used them as olfactory stimuli in a series of tasks examining whether and how they influence cooperative decision-making in an incentivized economic game and ratings of cooperativeness.

Schoolchildren cooperate more successfully with non-kin than with siblings.

Cooperation plays a key role in the development of advanced societies and can be stabilized through shared genes (kinship) or reciprocation. In humans, cooperation among kin occurs more readily than cooperation among non-kin. In many organisms, cooperation can shift with age (e.

Does he sound cooperative? Acoustic correlates of cooperativeness.

The sound of the voice has several acoustic features that influence the perception of how cooperative the speaker is. It remains unknown, however, whether these acoustic features are associated with actual cooperative behaviour. This issue is crucial to disentangle whether inferences of traits from voices are based on stereotypes, or facilitate the detection of cooperative partners.

Two facets of patience in young children: Waiting with and without an explicit reward.

Patience, or the ability to tolerate delay, is typically studied using delay of gratification (DoG) tasks. However, among other factors (e.g.

Split-Second Trustworthiness Detection From Faces in an Economic Game.

Economic interactions often imply to gauge the trustworthiness of others. Recent studies showed that when making trust decisions in economic games, people have some accuracy in detecting trustworthiness from the facial features of unknown partners. Here we provide evidence that this face-based trustworthiness detection is a fast and intuitive process by testing its performance at split-second levels of exposure.

Trustworthiness perception at zero acquaintance: Consensus, accuracy, and prejudice.

Research on trustworthiness perception from faces has unfolded in a way that is strikingly reminiscent of Jussim's narrative in his 2012 book. Jussim's analysis warns us against overemphasizing evidence about prejudice over evidence about accuracy, when both are scant; and reminds us to hold all accounts to the same standards, whether they call on societal biases or true signals.

Conflicting goals and their impact on games where payoffs are more or less ambiguous.

The two-dimensional map by Bentley et al. concerns decision-making and not games. The east-west dimension is interpreted as the level at which individuals identify with some larger group.

Low second-to-fourth digit ratio predicts indiscriminate social suspicion, not improved trustworthiness detection.

Testosterone administration appears to make individuals less trusting, and this effect has been interpreted as an adaptive adjustment of social suspicion, that improved the accuracy of trusting decisions. Here, we consider another possibility, namely that testosterone increases the subjective cost of being duped, decreasing the propensity to trust without improving the accuracy of trusting decisions. In line with this hypothesis, we show that second-to-fourth digit ratio (2D:4D, a proxy for effects of testosterone in the foetus) correlates with the propensity to trust, but not with the accuracy of trusting decisions.

The modular nature of trustworthiness detection.

The capacity to trust wisely is a critical facilitator of success and prosperity, and it has been conjectured that people of higher intelligence are better able to detect signs of untrustworthiness from potential partners. In contrast, this article reports five trust game studies suggesting that reading trustworthiness of the faces of strangers is a modular process. Trustworthiness detection from faces is independent of general intelligence (Study 1) and effortless (Study 2).

In love and war: altruism, norm formation, and two different types of group selection.

We analyse simulations reported in "The co-evolution of individual behaviors and social institutions" by Bowles et al., 2003 in the Journal of Theoretical Biology 223, 135-147, and begin with distinguishing two types of group selection models. The literature does not provide different names for them, but they are shown to be fundamentally different and have quite different empirical implications.

The co-evolution of individual behaviors and social institutions.

We present agent-based simulations of a model of a deme-structured population in which group differences in social institutions are culturally transmitted and individual behaviors are genetically transmitted. We use a standard extended fitness accounting framework to identify the parameter space for which this co-evolutionary process generates high levels of group-beneficial behaviors. We show that intergroup conflicts may explain the evolutionary success of both: (a) altruistic forms of human sociality towards unrelated members of one's group; and (b) group-level institutional structures such as food sharing which have emerged and diffused repeatedly in a wide variety of ecologies during the course of human history.