Human mate-choice copying is domain-general social learning

Investigating the effects of social information on spite in an online game

While humans are highly cooperative, they can also behave spitefully. Yet spite remains understudied. Spite can be normatively driven and while previous experiments have found some evidence that cooperation and punishment may spread via social learning, no experiments have considered the social transmission of spiteful behaviour. Here we present an online experiment where, following an opportunity to earn wealth, we asked participants to choose an action towards an anonymous partner across a full spectrum of social behaviour, from spite to altruism. In accordance with cultural evolutionary theory, participants were presented with social information that varied in source and content. Across six conditions, we informed participants that either the majority or the highest earner had chosen to behave spitefully, neutrally or altruistically. We found an overall tendency towards altruism, but at lower levels among those exposed to spite compared with altruism. We found no difference between social information that came from the majority or the highest earner. Exploratory analysis revealed that participants' earnings negatively correlated with altruistic behaviour. Our results contrast with previous literature that report high rates of spite in experimental samples and a greater propensity for individuals to copy successful individuals over the majority.

Agent-based models of the cultural evolution of occupational gender roles

The causes of sex differences in human behaviour are contested, with 'evolutionary' and 'social' explanations often being pitted against each other in the literature. Recent work showing positive correlations between indices of gender equality and the size of sex differences in behaviour has been argued to show support for 'evolutionary' over 'social' approaches. This argument, however, neglects the potential for social learning to generate arbitrary gender segregation. In the current paper we simulate, using agent-based models, a population where agents exist as one of two 'types' and can use social information about which types of agents are performing which 'roles' within their environment. We find that agents self-segregate into different roles even where real differences in performance do not exist, if there is a common belief (modelled as priors) that group differences may exist in 'innate' competence. Facilitating role changes such that agents should move without cost to the predicted highest-rewards for their skills (i.e. fluidity of the labour market) reduced segregation, while forcing extended exploration of different roles eradicated gender segregation. These models are interpreted in terms of bio-cultural evolution, and the impact of social learning on the expression of gender roles.

Is the Grass Really Greener? The Influence of Gender Identity and Sexual Orientation on Mate Copying Behaviors

Mate copying is a sexual strategy whereby individuals attend to socially available information about their prospective mate. This allows for more accurate decision making in regard to mating. This phenomenon was originally demonstrated among nonhumans, but there is an increasing weight of evidence suggesting that humans also engage in mate copying. Research typically focuses on heterosexual cisgender women, with no previous studies having looked at those identifying outside of the traditional gender binary. The current study aimed to address this gap by examining the impact of gender identity and sexual orientation on the propensity to engage in mate copying. Participants (N = 831) completed an online survey providing desirability ratings for photographs alone (T₁) and then rated the same photographs after receiving social information about the relationship status and previous relationship history of the pictured individual (T₂). It was found that both gender identity (F(4, 713) = 3.94, η_p² = .02) and sexual orientation (F(4, 713) = 4.40, η_p² = .02) influenced an individual's overall propensity to mate copy, and that desirability patterns for individuals were very different depending on these variables. It was concluded that while mate copying certainly is evident among humans, the phenomenon is extremely nuanced and sensitive.

The experimental evolution of human culture: flexibility, fidelity and environmental instability

The past 2 Myr have seen both unprecedented environmental instability and the evolution of the human capacity for complex culture. This, along with the observation that cultural evolution occurs faster than genetic evolution, has led to the suggestion that culture is an adaptation to an unstable environment. We test this hypothesis by examining the ability of human social learning to respond to environmental changes. We do this by inserting human participants (n = 4800) into evolutionary simulations with a changing environment while varying the social information available to individuals across five conditions. We find that human social learning shows some signs of adaptation to environmental instability, including critical social learning, the adoption of up-and-coming traits and, unexpectedly, contrariness. However, these are insufficient to avoid significant fitness declines when the environment changes, and many individuals are highly conformist, which exacerbates the fitness effects of environmental change. We conclude that human social learning reflects a compromise between the competing needs for flexibility to accommodate environmental change and fidelity to accurately transmit valuable cultural information.

Exploring the Influence of Race in Mate Copying Using Former Partner Evaluations

Human mate choice is a complex, nuanced process that incorporates factors including physical attractiveness, race, culture, and social values. Choosing the wrong partner can be a risky and costly affair; hence, mate choosers may copy the choices of others to inform their own decisions about the mate quality of a potential partner. This phenomenon is known as mate copying (MC). Consistent with previous research methods, the current study presented a sample of 461 Australian women with photographic stimuli of target men of one of three races paired with a description of a former female partner evaluating the target man either positively or negatively. Racial similarity between participants and the target man was statistically controlled for. As hypothesised, positive evaluations elicited MC whereas negative evaluations elicited mate avoidance. Racial similarity was also shown to influence measures of desirability and MC propensity. Results were discussed within the context of existing human MC literature, with particular emphasis on exploring how new factors affect the expression of MC intent within the Australian female demographic. Recommendations for further research based on these outcomes were also made.

What You See May Be What You Want: Mate Copying in a Natural Setting

Objectives

The phenomenon of mate copying (MC) suggests that an individual’s romantic desirability varies, to some degree, as a function of their romantic experiences. By manipulating relationship history, this research aimed to determine whether male desirability varied similarly for static stimuli (photographs) as it did for dynamic stimuli (short clips). Here we present 2 studies examining this idea.

Methods

In both studies heterosexual women aged 18–34 were recruited from social media and evaluated the desirability of men, before and after being given information about the level of relationship experience the men had previously had (either ‘none’, ‘some’, or ‘lots’).

Results

In Study 1 (N = 278), we employed static images of men and Study 2 (N = 66) was methodologically similar but employed dynamic stimuli. Study 1 indicated that a man’s desirability to heterosexual women increased when it was revealed that he had a moderate amount of relationship experience but decreased if he had none. Results from Study 2 suggested that desirability was not affected by an individual’s relationship experience.

Conclusions

MC was indicated when stimuli were static, but not when they were dynamic. These results suggest that MC may be a phenomenon that exists to a greater extent when stimuli are less informative.

Sexual selection and the ascent of women: Mate choice research since Darwin

Darwin's theory of sexual selection fundamentally changed how we think about sex and evolution. The struggle over mating and fertilization is a powerful driver of diversification within and among species. Contemporaries dismissed Darwin's conjecture of a "taste for the beautiful" as favoring particular mates over others, but there is now overwhelming evidence for a primary role of both male and female mate choice in sexual selection. Darwin's misogyny precluded much analysis of the "taste"; an increasing focus on mate choice mechanisms before, during, and after mating reveals that these often evolve in response to selection pressures that have little to do with sexual selection on chosen traits. Where traits and preferences do coevolve, they can do so whether fitness effects on choosers are positive, neutral, or negative. The spectrum of selection on traits and preferences, and how traits and preferences respond to social effects, determine how sexual selection and mate choice influence broader-scale processes like reproductive isolation and population responses to environmental change.

Limited evidence of hierarchical encoding in the cheerleader effect

"The cheerleader effect" refers to the increase in attractiveness that an individual face experiences when seen in a group of other faces. It has been proposed that the cheerleader effect occurs because (a) the visual system rapidly summarises a group of faces into an ensemble representation, (b) which is hypothesised to be highly attractive because of its average facial characteristics, and (c) observers remember individual faces to be more alike the ensemble representation than they were, due to hierarchical structure of visual working memory. Across three experiments, we investigated whether the cheerleader effect is consistent with hierarchical encoding, by asking observers to give attractiveness ratings to the same target faces shown in groups and alone. Consistent with hierarchical encoding, the largest attractiveness increases of 1.5-2.0% occurred when target faces were presented in groups of faces that could be mentally summarised to create an ensemble representation with average facial characteristics. Surprisingly, smaller cheerleader effects still occurred in conditions that were incompatible with hierarchical encoding (i.e., groups with non-human images). Together, these results offer only limited evidence for the role of hierarchical encoding in the cheerleader effect, suggesting that alternative mechanisms must be explored in future research.

How Do Ideal Friend Preferences and Interaction Context Affect Friendship Formation? Evidence for a Domain- General Relationship Initiation Process

This research examined how people’s ideal friend preferences influence the friendship formation process. In an extension of prior research on romantic relationship initiation, we tested whether the match between participants’ ideals and a partner’s traits affected participants’ interest in forming a new friendship in three contexts: evaluating a potential friend’s profile, meeting in-person, and chatting online. Results revealed that participants were more interested in becoming friends with a partner whose traits matched (vs. mismatched) their ideal friend preferences when evaluating his or her profile. After a live interaction, however, the effect of the ideal-perceived trait match manipulation on participants’ friendship interest was substantially reduced in both in-person and online chatting contexts. People’s ideal friend preferences may influence their friendship interest more strongly in descriptive (i.e., indirect) than interactive (i.e., direct) contexts, a finding that mirrors prior results from the romantic domain and documents a role for domain-general relationship initiation processes.