Evolutionary Human Sciences最新文献

Just like in human infants, ostensive verbal utterances can transform human actions into a natural teaching scenario for dogs. However, functional selection created 'independent' and 'cooperative' dog breeds with different dependence on human signals. We hypothesize that this could affect dogs' sensitivity towards verbal communication. We tested independent and cooperative breeds in the two-choice 'A-not-B paradigm'. The experimenter used either ostensive or neutral intonation speech while hiding the target. Based on the target's position, the trial order was A-A-B-B-A. Perseverative 'A-not-B' errors in Trial 3 are interpreted as learning the rule to look for the reward at location 'A'. From the near 100% success rate in Trials 1 and 2, each groups' performance dropped to chance level in Trial 3, except for cooperative dogs in the neutral speech condition. Independent dogs in the neutral speech condition paid the least attention to the experimenter. We conclude that perseverative errors can be either the consequence of rule-learning elicited by ostensive intonation or reverting to the 'win-stay' strategy, when independent dogs lost interest in watching where the experimenter exactly hid the reward. Functional selection could influence dogs' general attentiveness towards human communication; thus, neutral speech may have an underestimated relevance for cooperative dogs.

[This corrects the article DOI: 10.1017/ehs.2025.10012.].

Religious diversity has had profound consequences in human history, but the dynamics of how it evolves remain unclear. One unresolved question is the extent to which religious denominations accumulate gradually or are generated in rapid bursts associated with specific historical events. Anecdotal evidence tends to favour the second view, but quantitative evidence on a global scale is lacking. Phylogenetic methods that treat religious denominations as evolving lineages can help to resolve this question. Here we apply computational phylogenetic methods to a purpose-built data set documenting 291 religious denominations and their genealogical relationships to derive dated phylogenies of three families of world religions - Indo-Iranian, Islamic, and Judeo-Christian. We model the birth of new denominations along the branches of these phylogenies, test for shifts in the birth rate, and draw tentative links between the shifts we find and religious history. We find evidence for birth rate shifts in the Islamic and Judeo-Christian families, corresponding to at least three separate events that have shaped global religious diversity.

Typically feminine morphological traits in women include a neotenous facial structure with large eyes, full lips, and an oval face shape, and a curvaceous body with large breasts, a narrow waist, and full hips and buttocks. Compared to men, women also show higher second-to-fourth finger (2D:4D) ratios as well as less muscle mass, lower physical strength, and a higher voice pitch. Due to a putative association with oestrogen levels, feminine traits are often claimed to cue women's reproductive potential. However, the evidence for this is scarce and inconsistent, typically measuring proxies rather than actual fertility outcomes. Here, we report a systematic review of direct fertility measures as a function of morphological traits in women, including breast size, waist-to-hip ratio (WHR), voice pitch, strength, and 2D:4D; no articles were found measuring facial femininity. The review included 19 articles comprising 68 effect sizes (31 samples from 16 countries; total N = 125,062). Our review showed that a less feminine WHR may cue past fertility, and a more feminine 2D:4D may be, at best, weakly associated with fertility. Overall, we conclude that the current evidence base is too weak to support the claim that women's feminine morphological traits are associated with reproductive potential.

Despite growing consensus that cognitive differences between Neanderthals and modern humans were not as significant as once assumed, visual art remains disproportionately associated with Homo sapiens. This paper explores why that is. Rather than appealing to underlying cognition, we argue that early art was pushed and pulled by social dynamics and demographic contexts on a larger scale and eventually formed through cultural transmission. Drawing on the archaeological record, we focus on pigment use, ornamentation, engravings and painting. We suggest that these practices initially remained ad hoc while still functioning as tools for social signalling and intergroup communication in the small-scale communities of Neanderthals and early modern humans. We argue that visual art moved beyond ad hoc practices under conditions of increased population density and interaction - first via the crystallization of art as a tradition and second, as cumulative cultural art. Lack of cognitive ability is not a well-supported explanation for the empirical low frequency of Neanderthal art. Instead, we propose effects of differences in social connectivity and population densities as an alternative. By reframing art as a flexible, context-dependent behaviour, we challenge essentialist models and advocate for a pluralistic view of cognitive and cultural expression across different hominin groups.

Bipedalism is a distinguishing feature of our species and, as such, there has been much interest in the energetic costs and foraging returns of walking and running, especially among hunter-gatherer societies. However, humans routinely exhibit extensive locomotor versatility, with hunter-gatherers consistently also swimming, diving, and climbing. Additionally, the fitness costs and benefits of locomotion extend well beyond energy income and expenditure. Here, we review evidence from over 900 ethnographic documents across a worldwide sample of more than 50 hunter-gatherer societies to examine the fitness costs and benefits of walking, running, climbing, swimming, and diving. We show that the fitness costs and benefits of locomotor engagement consistently extend well beyond energetics to include, for example, currencies of status, protection from hazards, and risks of injury or death. These fitness factors differ in significance between locomotor modalities, with implications for the comparison of bipedal and non-bipedal locomotion. For example, while energetic demands represent the major cost of most bipedal engagements, the fitness implications of potential fall injuries may outweigh those of energetics in tree climbing. These results inform existing debates relating to hominin locomotor evolution and hunter-gatherer behavioural ecology.

Sex-specific division of labour and the associated use of different subsistence techniques by males (e.g. hunting) and females (e.g. gathering) has played an important role in shaping human societies. Skills needed in adulthood are practiced in play during childhood and object play has been proposed to foster tool-use skills necessary for adult subsistence techniques. Here, we investigated sex differences in the ontogeny of object play in Tsimane children in Bolivia to understand its potential role in shaping gender-specific adult roles. We used observational data (>80,000 scan samples) from nine Tsimane communities collected between 2002 and 2007. We analysed age and sex differences in general play, object play, and object types. Our results show that both general play and object play peaked in early to middle childhood (3.5-7.5 years of age), with boys spending more time playing. Moreover, boys engaged more with objects related to male-specific roles (e.g. hunting tools), while girls played more with objects related to female-specific roles (e.g. cooking tools). Our findings suggest that object play serves as an adaptive, culturally embedded pathway to develop gender-specific adult skills. Studying developmental patterns of object play across human cultures enriches our understanding of the evolutionary contexts shaping divisions of labour.

Recent years have seen growing interest in applying the Evolutionary Transitions in Individuality (ETI) framework to human sociocultural evolution. Proponents argue that human societies exhibit features - such as multilevel organization, cooperation, and division of labour - sufficiently analogous to biological ETIs to warrant theoretical extension. This paper critically assesses such claims and argues that they rest on a fundamental misapplication of the ETI framework. Drawing on recent work in cultural evolution, I show that sociocultural systems typically lack the core conditions required for an ETI, including autonomous reproduction at the group level and the operation of natural selection in the reproductive mode. Attempts to relax these criteria risk undermining the coherence of the framework itself. I conclude that although the broader framework of Major Evolutionary Transitions may still have value for understanding sociocultural change, the specific explanatory structure of ETI theory does not transfer.

The manosphere is a collection of online antifeminist men's groups whose ideologies often invoke Darwinian principles and evolutionary psychological research. In the present study, we reveal that the manosphere generates its own untested and speculative evolutionary hypotheses, or 'just-so stories', about men, women, and society. This is a unique phenomenon, where lay (i.e. non-expert) individuals creatively employ evolutionary reasoning to explain phenomena in accordance with their particular worldview. We thus assembled the first dataset of lay evolutionary just-so stories extracted from manosphere content (n = 102). Through qualitative analysis, we highlight the particularity of the manosphere's lay evolutionism. It is a collective bottom-up endeavour, which often leads to practical advice and exhibits a male gender bias. We further show that 83.3% of manosphere just-so stories pertain to sex differences and that only 36.3% explicitly signal that they are speculative. Given this evidence that lay communities collectively engage in evolutionary hypothesizing, we reflect on implications for evolutionary scholars and for the field as a whole in terms of ethics and public image. Lastly, we issue a call for renewed discussion and reflection on evolutionary hypothesizing, a central yet somewhat neglected feature of evolutionary behavioural science.

Culture consists of practices - behaviour patterns - shared by members of a group. Some attempts to demonstrate evolution of cultural practices in the laboratory have shown evolution of material products, such as paper aeroplanes. Some attempts have shown evolution of actual group behaviour. The present experiments demonstrated evolution of group coordination across generations in punishing defection in a public-goods game. Cost of punishing defection varied across replicates that consisted of series of groups (generations) of 10 undergraduates each. Each generation played the game anonymously for 10 rounds and could write messages to the other participants and punish defection every round. The effectiveness of punishment depended on the number of participants choosing to punish. In Experiment 1, cultural transmission from generation to generation consisted of written advice from one generation read aloud to the next generation. In Experiment 2, transmission from generation to generation consisted of having some participants return from the previous group. The cost of punishing varied across replicates: zero, one, two or five cents. In both experiments, the evolution of altruistic punishing was strongly dependent on the cost of punishing. The results add to plausibility of studying evolution of complex behaviour patterns like cooperation in the laboratory.