Fears about artificial intelligence across 20 countries and six domains of application.

The frontier of artificial intelligence (AI) is constantly moving, raising fears and concerns whenever AI is deployed in a new occupation. Some of these fears are legitimate and should be addressed by AI developers-but others may result from psychological barriers, suppressing the uptake of a beneficial technology. Here, we show that country-level variations across occupations can be predicted by a psychological model at the individual level.

Trade-offs, control conditions, and alternative designs in the experimental study of cultural evolution.

Although the theoretical foundations of the modern field of cultural evolution have been in place for over 50 y, laboratory experiments specifically designed to test cultural evolutionary theory have only existed for the last two decades. Here, we review the main experimental designs used in the field of cultural evolution, as well as major findings related to the generation of cultural variation, content- and model-based biases, cumulative cultural evolution, and nonhuman culture. We then identify methodological advances that demonstrate the iterative improvement of cultural evolution experimental methods.

Contemporary small-scale subsistence populations offer unique insights into human musculoskeletal health and aging.

Human foragers avoid noncommunicable diseases that are leading causes of mortality, partly because physically active lifestyles promote healthy aging. High activity levels also promote tissue damage accumulation from wear-and-tear, increase risk of injury and disability which compromise productivity, and reduce energetic investments in somatic maintenance given constrained energy expenditure. Constraints intensify when nutrient supply is limited and surplus energy is directed toward pathogen defense and reproduction, as occurred throughout hominin evolution.

BaYaka mothers balance childcare and subsistence tasks during collaborative foraging in Congo Basin.

Across cultures, mothers balance childcare with other labour. Hunter-gatherer mothers face a daily choice of whether to take infants on foraging trips or leave them with caregivers in the settlement, as well as deciding with whom to forage. Yet, it remains unclear how infant presence affects mothers' mobility and food returns during group foraging.

Proximate and ultimate drivers of norms and norm change.

We describe a formal model of norm psychology that can be applied to better understand norm change. The model integrates several proximate drivers of normative behavior: beliefs and preferences about a) material payoffs, b) personal norms, c) peer disapproval, d) conformity, and e) authority compliance. Additionally, we review interdisciplinary research on ultimate foundations of these proximate drivers of normative behavior.

Do institutions evolve like material technologies?

Norms and institutions enable large-scale human cooperation by creating shared expectations and changing individuals' incentives via monitoring or sanctioning. Like material technologies, these social technologies satisfy instrumental ends and solve difficult problems. However, the similarities and differences between the evolution of material technologies and the evolution of social technologies remain unresolved.

Lie detection algorithms disrupt the social dynamics of accusation behavior.

Humans, aware of the social costs associated with false accusations, are generally hesitant to accuse others of lying. Our study shows how lie detection algorithms disrupt this social dynamic. We develop a supervised machine-learning classifier that surpasses human accuracy and conduct a large-scale incentivized experiment manipulating the availability of this lie-detection algorithm.

A social learning primacy trend in mate-copying: an experiment in .

Social learning is learning from the observation of how others interact with the environment. However, in nature, individuals often need to process serial social information and may favour either the most recent information (recency bias), constantly updating knowledge to match the environment, or the information that appeared first in the series (primacy bias), which may slow down adjustment to environmental change. Mate-copying is a widespread form of social learning in a mate choice context related to conformity in mate choice, and where a naive individual develops a preference for a given mate (or mate phenotype) seen being chosen by conspecifics.

Gender inequality in workloads explained by operational sex ratio.

Ecological differences between human populations can affect the relative strength of sexual selection, and hence drive gender inequality. Here, we exploit the cultural diversity of southwestern China, where some village sex ratios are female-biased, in part due to a proportion of males entering monastic celibacy, to evaluate the role of sex ratio on the sexual division of labor. We used a detachable activity tracker to measure workload by step counts in both sexes among 561 individuals in 55 villages in six different areas.

The evolution of environmentally mediated social interactions and posthumous spite under isolation by distance.

Many social interactions happen indirectly via modifications of the environment, e.g. through the secretion of functional compounds or the depletion of renewable resources.

A shared "optimal-level of arousal": Seeking basis for creativity and curiosity.

We argue that the phases identified in the novelty-seeking model can be clarified by considering an updated version of the optimal-level of arousal model, which incorporates the "arousal" and "mood changing" potentials of stimuli and contexts. Such a model provides valuable insights into what determines one's state of mind, inter-individual differences, and the rewarding effects of curiosity and creativity.

Noise and opinion dynamics: how ambiguity promotes pro-majority consensus in the presence of confirmation bias.

Opinion dynamics are affected by cognitive biases and noise. While mathematical models have focused extensively on biases, we still know surprisingly little about how noise shapes opinion patterns. Here, we use an agent-based opinion dynamics model to investigate the interplay between confirmation bias-represented as bounded confidence-and different types of noise.

Differences in expression of male aggression between wild bonobos and chimpanzees.

Researchers investigating the evolution of human aggression look to our closest living relatives, bonobos (Pan paniscus) and chimpanzees (Pan troglodytes), as valuable sources of comparative data. Males in the two species exhibit contrasting patterns: male chimpanzees sexually coerce females and sometimes kill conspecifics, whereas male bonobos exhibit less sexual coercion and no reported killing. Among the various attempts to explain these species differences, the self-domestication hypothesis proposes negative fitness consequences of male aggression in bonobos.

Environmental harshness does not affect the propensity for social learning in great tits, Parus major.

According to the harsh environment hypothesis, natural selection should favour cognitive mechanisms to overcome environmental challenges. Tests of this hypothesis to date have largely focused on asocial learning and memory, thus failing to account for the spread of information via social means. Tests in specialized food-hoarding birds have shown strong support for the effects of environmental harshness on both asocial and social learning.

Efficiency and resilience of cooperation in asymmetric social dilemmas.

Direct reciprocity is a powerful mechanism for cooperation in social dilemmas. The very logic of reciprocity, however, seems to require that individuals are symmetric, and that everyone has the same means to influence each others' payoffs. Yet in many applications, individuals are asymmetric.

Women's subsistence strategies predict fertility across cultures, but context matters.

While it is commonly assumed that farmers have higher, and foragers lower, fertility compared to populations practicing other forms of subsistence, robust supportive evidence is lacking. We tested whether subsistence activities-incorporating market integration-are associated with fertility in 10,250 women from 27 small-scale societies and found considerable variation in fertility. This variation did not align with group-level subsistence typologies.

Cross-societal variation in norm enforcement systems.

Across human societies, people are sometimes willing to punish norm violators. Such punishment can take the form of revenge from victims, seemingly altruistic intervention from third parties, or legitimized sanctioning from institutional representatives. Although prior work has documented cross-cultural regularities in norm enforcement, substantial variation exists in the prevalence and forms of punishment across societies.

Child and adolescent foraging: New directions in evolutionary research.

Young children and adolescents in subsistence societies forage for a wide range of resources. They often target child-specific foods, they can be very successful foragers, and they share their produce widely within and outside of their nuclear family. At the same time, while foraging, they face risky situations and are exposed to diseases that can influence their immune development.

Women's subsistence networks scaffold cultural transmission among BaYaka foragers in the Congo Basin.

In hunter-gatherer societies, women's subsistence activities are crucial for food provisioning and children's social learning but are understudied relative to men's activities. To understand the structure of women's foraging networks, we present 230 days of focal-follow data in a BaYaka community. To analyze these data, we develop a stochastic blockmodel for repeat observations with uneven sampling.

Universality, domain-specificity, and development of psychological responses to music.

Humans can find music happy, sad, fearful, or spiritual. They can be soothed by it or urged to dance. Whether these psychological responses reflect cognitive adaptations that evolved expressly for responding to music is an ongoing topic of study.

Characterization of children's verbal input in a forager-farmer population using long-form audio recordings and diverse input definitions.

There is little systematically collected quantitative empirical data on how much linguistic input children in small-scale societies encounter, with some estimates suggesting low levels of directed speech. We report on an ecologically-valid analysis of speech experienced over the course of a day by young children (N = 24, 6-58 months old, 33% female) in a forager-horticulturalist population of lowland Bolivia. A permissive definition of input (i.

The shirker's dilemma and the prospect of cooperation in large groups.

Cooperation usually becomes harder to sustain as groups become larger because incentives to shirk increase with the number of potential contributors to collective action. But is this always the case? Here we study a binary-action cooperative dilemma where a public good is provided as long as not more than a given number of players shirk from a costly cooperative task. We find that at the stable polymorphic equilibrium, which exists when the cost of cooperation is low enough, the probability of cooperating increases with group size and reaches a limit of one when the group size tends to infinity.