Pub Date : 2025-10-23eCollection Date: 2025-01-01DOI: 10.1017/ehs.2025.10022
Ava Moser, Michael D Gurven, Hillard Kaplan, Benjamin Trumble, Jonathan Stieglitz, Paul Hooper, Daniel Cummings, Adrian Jaeggi, Kathelijne Koops
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.
{"title":"Object play in Tsimane children: implications for sex-specific division of labour.","authors":"Ava Moser, Michael D Gurven, Hillard Kaplan, Benjamin Trumble, Jonathan Stieglitz, Paul Hooper, Daniel Cummings, Adrian Jaeggi, Kathelijne Koops","doi":"10.1017/ehs.2025.10022","DOIUrl":"https://doi.org/10.1017/ehs.2025.10022","url":null,"abstract":"<p><p>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.</p>","PeriodicalId":36414,"journal":{"name":"Evolutionary Human Sciences","volume":"7 ","pages":"e37"},"PeriodicalIF":2.2,"publicationDate":"2025-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12645321/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145640832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-10eCollection Date: 2025-01-01DOI: 10.1017/ehs.2025.10021
Arsham Nejad Kourki
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.
{"title":"Major transitions in sociocultural evolution.","authors":"Arsham Nejad Kourki","doi":"10.1017/ehs.2025.10021","DOIUrl":"https://doi.org/10.1017/ehs.2025.10021","url":null,"abstract":"<p><p>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.</p>","PeriodicalId":36414,"journal":{"name":"Evolutionary Human Sciences","volume":"7 ","pages":"e39"},"PeriodicalIF":2.2,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12645318/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145640794","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-09eCollection Date: 2025-01-01DOI: 10.1017/ehs.2025.10020
Louis Bachaud, Macken Murphy, Sarah E Johns
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.
{"title":"A hundred and two just-so stories: exploring the lay evolutionary hypotheses of the manosphere.","authors":"Louis Bachaud, Macken Murphy, Sarah E Johns","doi":"10.1017/ehs.2025.10020","DOIUrl":"https://doi.org/10.1017/ehs.2025.10020","url":null,"abstract":"<p><p>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 (<i>n</i> = 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.</p>","PeriodicalId":36414,"journal":{"name":"Evolutionary Human Sciences","volume":"7 ","pages":"e41"},"PeriodicalIF":2.2,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12645320/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145640693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-09-15eCollection Date: 2025-01-01DOI: 10.1017/ehs.2025.10018
William M Baum, Peter J Richerson
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.
{"title":"Cultural evolution in the laboratory: evolution of cooperative altruistic punishing.","authors":"William M Baum, Peter J Richerson","doi":"10.1017/ehs.2025.10018","DOIUrl":"https://doi.org/10.1017/ehs.2025.10018","url":null,"abstract":"<p><p>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.</p>","PeriodicalId":36414,"journal":{"name":"Evolutionary Human Sciences","volume":"7 ","pages":"e32"},"PeriodicalIF":2.2,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12645323/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145640720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-09-08eCollection Date: 2025-01-01DOI: 10.1017/ehs.2025.10019
Richard Meitern, Peeter Hõrak
This register-based study investigates how natural selection acts on educational attainment and reproductive timing among Estonians born between 1925 and 1977. Women with primary education consistently achieved the highest reproductive success throughout the study period, whereas a positive educational gradient in reproduction emerged among men born since the 1950s, resulting in sexually antagonistic selection on educational attainment. Men with tertiary education had higher reproductive success than other men, despite initiating reproduction later. The lowest-educated women exhibited the strongest selection for early reproduction and the earliest start of reproduction throughout the study period. These women and the least-educated men also experienced the strongest selection for delayed reproductive cessation. Nonetheless, parents with primary education (particularly men) were typically the first to stop reproducing. Stabilizing selection for intermediate interbirth intervals also showed the strongest quadratic selection gradients among minimally educated parents of both sexes. At that, men with primary education had the fastest reproductive pace, whereas women in the same group had the slowest. Our study shows that selection on reproductive timing traits was consistently stronger among parents with lower educational attainment, and that variation in reproductive timing across educational strata does not consistently reflect the selective pressures acting on recent generations.
{"title":"Natural selection on reproductive timing varies by education in twentieth-century Estonia.","authors":"Richard Meitern, Peeter Hõrak","doi":"10.1017/ehs.2025.10019","DOIUrl":"https://doi.org/10.1017/ehs.2025.10019","url":null,"abstract":"<p><p>This register-based study investigates how natural selection acts on educational attainment and reproductive timing among Estonians born between 1925 and 1977. Women with primary education consistently achieved the highest reproductive success throughout the study period, whereas a positive educational gradient in reproduction emerged among men born since the 1950s, resulting in sexually antagonistic selection on educational attainment. Men with tertiary education had higher reproductive success than other men, despite initiating reproduction later. The lowest-educated women exhibited the strongest selection for early reproduction and the earliest start of reproduction throughout the study period. These women and the least-educated men also experienced the strongest selection for delayed reproductive cessation. Nonetheless, parents with primary education (particularly men) were typically the first to stop reproducing. Stabilizing selection for intermediate interbirth intervals also showed the strongest quadratic selection gradients among minimally educated parents of both sexes. At that, men with primary education had the fastest reproductive pace, whereas women in the same group had the slowest. Our study shows that selection on reproductive timing traits was consistently stronger among parents with lower educational attainment, and that variation in reproductive timing across educational strata does not consistently reflect the selective pressures acting on recent generations.</p>","PeriodicalId":36414,"journal":{"name":"Evolutionary Human Sciences","volume":"7 ","pages":"e33"},"PeriodicalIF":2.2,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12645315/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145640875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-08-28eCollection Date: 2025-01-01DOI: 10.1017/ehs.2025.10004
Caroline Uggla, Jan Saarela
[This corrects the article DOI: 10.1017/ehs.2025.9.].
[此更正文章DOI: 10.1017/ehs.2025.9.]。
{"title":"Erratum: Breaking-up and breaking the norm: intergenerational divorce transmission among two ethnolinguistic groups - CORRIGENDUM.","authors":"Caroline Uggla, Jan Saarela","doi":"10.1017/ehs.2025.10004","DOIUrl":"https://doi.org/10.1017/ehs.2025.10004","url":null,"abstract":"<p><p>[This corrects the article DOI: 10.1017/ehs.2025.9.].</p>","PeriodicalId":36414,"journal":{"name":"Evolutionary Human Sciences","volume":"7 ","pages":"e34"},"PeriodicalIF":2.2,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12645314/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145640778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-08-27eCollection Date: 2025-01-01DOI: 10.1017/ehs.2025.10005
Gabriel Aguirre-Fernández, Chiara Barbieri, Stephen C Jett, Jorge D Carrillo-Briceño, Rodrigo Cámara-Leret, Marcelo R Sánchez-Villagra
The blowgun is a weapon that employs the force of breath for expelling a projectile and has been traditionally used for hunting and (occasionally) war. The use of blowguns extends to ancient times and is advantageous in dense-forest areas of South America and South East Asia. A classification system of blowgun types introduced in 1948 for South America is extended here. We assembled a global database that includes collection data and ethnographic accounts of blowgun types and other related features that were linked to available linguistic information. Our analyses show that geography explains the distribution of blowgun types to some degree, but within regions of the world it is possible to identify cultural connections. Darts are by far the most used projectiles and in combination with toxins (e.g. curare), these weapons reach their highest potential. A case study on the use of blowguns in groups of Austronesian language speakers shows clade-specific preferences across the tree. Our comprehensive database provides a general overview of large-scale patterns and suggests that incorporation of other related data (e.g. sights, mouthpieces, quivers) would enhance the understanding of fine-scale cultural patterns.
{"title":"A global database on blowguns with links to geography and language.","authors":"Gabriel Aguirre-Fernández, Chiara Barbieri, Stephen C Jett, Jorge D Carrillo-Briceño, Rodrigo Cámara-Leret, Marcelo R Sánchez-Villagra","doi":"10.1017/ehs.2025.10005","DOIUrl":"10.1017/ehs.2025.10005","url":null,"abstract":"<p><p>The blowgun is a weapon that employs the force of breath for expelling a projectile and has been traditionally used for hunting and (occasionally) war. The use of blowguns extends to ancient times and is advantageous in dense-forest areas of South America and South East Asia. A classification system of blowgun types introduced in 1948 for South America is extended here. We assembled a global database that includes collection data and ethnographic accounts of blowgun types and other related features that were linked to available linguistic information. Our analyses show that geography explains the distribution of blowgun types to some degree, but within regions of the world it is possible to identify cultural connections. Darts are by far the most used projectiles and in combination with toxins (e.g. curare), these weapons reach their highest potential. A case study on the use of blowguns in groups of Austronesian language speakers shows clade-specific preferences across the tree. Our comprehensive database provides a general overview of large-scale patterns and suggests that incorporation of other related data (e.g. sights, mouthpieces, quivers) would enhance the understanding of fine-scale cultural patterns.</p>","PeriodicalId":36414,"journal":{"name":"Evolutionary Human Sciences","volume":"7 ","pages":"e26"},"PeriodicalIF":2.2,"publicationDate":"2025-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12516597/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145293962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-08-26eCollection Date: 2025-01-01DOI: 10.1017/ehs.2025.10016
Bret Beheim
How does information infrastructure shape long-term cultural evolution? Using over four centuries of professional game records from the game of Go, this study explores how strategic dynamics in opening moves reflect historical shifts in the 'infostructure' of skilled Go players. Drawing from recent work on how population size, AI, and information technology affect cultural evolution and innovation dynamics, I analyze over 118,000 games using measures of cultural diversity, divergence, and player network composition. The results show distinct eras of collective innovation and homogenization, including an early 20th-century explosion of novel opening strategies, a Cold-War-era die-off, and a recent increase in evolutionary tempo with the arrival of the internet and superhuman AI programmes like AlphaGo. Player population size shows an inverse-U relationship with opening move diversity, and a recent decline in strategic diversity has accompanied a shift in the player network, from many small subgroups to a few large ones. Surprisingly, the influence of AI has produced only a modest, short-lived disruption in the distribution of opening moves, suggesting convergence between humans and AI and incremental rather than revolutionary cultural change.
{"title":"Opening strategies in the game of go from feudalism to superhuman AI.","authors":"Bret Beheim","doi":"10.1017/ehs.2025.10016","DOIUrl":"10.1017/ehs.2025.10016","url":null,"abstract":"<p><p>How does information infrastructure shape long-term cultural evolution? Using over four centuries of professional game records from the game of Go, this study explores how strategic dynamics in opening moves reflect historical shifts in the 'infostructure' of skilled Go players. Drawing from recent work on how population size, AI, and information technology affect cultural evolution and innovation dynamics, I analyze over 118,000 games using measures of cultural diversity, divergence, and player network composition. The results show distinct eras of collective innovation and homogenization, including an early 20th-century explosion of novel opening strategies, a Cold-War-era die-off, and a recent increase in evolutionary tempo with the arrival of the internet and superhuman AI programmes like AlphaGo. Player population size shows an inverse-U relationship with opening move diversity, and a recent decline in strategic diversity has accompanied a shift in the player network, from many small subgroups to a few large ones. Surprisingly, the influence of AI has produced only a modest, short-lived disruption in the distribution of opening moves, suggesting convergence between humans and AI and incremental rather than revolutionary cultural change.</p>","PeriodicalId":36414,"journal":{"name":"Evolutionary Human Sciences","volume":"7 ","pages":"e28"},"PeriodicalIF":2.2,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12516593/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145293965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-08-22eCollection Date: 2025-01-01DOI: 10.1017/ehs.2025.10017
Eva Kundtová Klocová, Radek Kundt, Pushkar Varma Puryag, Martin Lang
Humans often participate in physically harmful and demanding rituals with no apparent material benefits. Although such behaviours have traditionally been explained using the lens of costly signalling theory, we question whether the canonical theory can be applied to the case of human cooperative signals and introduce a modification of this theory based on differential benefit estimation. We propose that along with cooperative benefits, committed members also believe in supernaturally induced benefits, which motivate participation in extreme rituals and stabilize their effects on cooperative assortment. Using Thaipusam Kavadi as a prototypical costly ritual, Tamil (ingroup) and Christian (outgroup) participants in Mauritius (N = 369) assessed the cost and benefits of Kavadi participation or hiking. We found that ingroup participants estimated material costs as larger than outgroups, physical costs as lower, and benefits as larger. These findings suggest that estimated costs may vary by modality and cultural expectations (e.g. Kavadi participants are not supposed to display pain), while supernaturally induced benefits were consistently reported as larger by ingroups compared to outgroups. We conclude that differential estimation of ritual benefits, not costs, are key to the persistence of extreme rituals and their function in the assortment of committed members, underscoring the role of differential estimation in the cognitive computation of signal utility.
{"title":"Estimated costs and benefits of participation in an extreme ritual in Mauritius.","authors":"Eva Kundtová Klocová, Radek Kundt, Pushkar Varma Puryag, Martin Lang","doi":"10.1017/ehs.2025.10017","DOIUrl":"https://doi.org/10.1017/ehs.2025.10017","url":null,"abstract":"<p><p>Humans often participate in physically harmful and demanding rituals with no apparent material benefits. Although such behaviours have traditionally been explained using the lens of costly signalling theory, we question whether the canonical theory can be applied to the case of human cooperative signals and introduce a modification of this theory based on differential benefit estimation. We propose that along with cooperative benefits, committed members also believe in supernaturally induced benefits, which motivate participation in extreme rituals and stabilize their effects on cooperative assortment. Using Thaipusam Kavadi as a prototypical costly ritual, Tamil (ingroup) and Christian (outgroup) participants in Mauritius (<i>N</i> = 369) assessed the cost and benefits of Kavadi participation or hiking. We found that ingroup participants estimated material costs as larger than outgroups, physical costs as lower, and benefits as larger. These findings suggest that estimated costs may vary by modality and cultural expectations (e.g. Kavadi participants are not supposed to display pain), while supernaturally induced benefits were consistently reported as larger by ingroups compared to outgroups. We conclude that differential estimation of ritual benefits, not costs, are key to the persistence of extreme rituals and their function in the assortment of committed members, underscoring the role of differential estimation in the cognitive computation of signal utility.</p>","PeriodicalId":36414,"journal":{"name":"Evolutionary Human Sciences","volume":"7 ","pages":"e29"},"PeriodicalIF":2.2,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12645328/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145640712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-08-20eCollection Date: 2025-01-01DOI: 10.1017/ehs.2025.10015
Sergi Valverde, Blai Vidiella, Andrej Spiridonov, R Alexander Bentley
Arcade video games evolved in a constrained design space, following patterns of diversification, stabilisation, and collapse that mirror macroevolutionary processes. Despite their historical significance and detailed digital records, arcade games remain underexplored in cultural evolution research. Drawing on a dataset of 7,205 machines spanning four decades, we reconstruct the evolutionary trajectories of arcade niches using a multi-scale framework that integrates trait-level innovation, genre-level selection, and systemic constraints. We identify two contrasting dynamics: (1) resilient genres-such as Fighter and Driving-maintained long-term viability through innovation and collaboration networks, while (2) early Maze and Shooter subgenres collapsed due to imitation and weak collaboration. Morphospace analysis reveals how technological traits-specifically CPU speed and ROM size-co-evolved with gameplay complexity, shaping the viable design space. We argue that genres operated as evolving cultural-ecological units-structured niches that shaped trait evolution through reinforcement, constraint, and feedback. This multi-scale perspective positions arcade games as a rich model system for studying cultural macroevolution.
{"title":"The cultural macroevolution of arcade video games: innovation, collaboration, and collapse.","authors":"Sergi Valverde, Blai Vidiella, Andrej Spiridonov, R Alexander Bentley","doi":"10.1017/ehs.2025.10015","DOIUrl":"https://doi.org/10.1017/ehs.2025.10015","url":null,"abstract":"<p><p>Arcade video games evolved in a constrained design space, following patterns of diversification, stabilisation, and collapse that mirror macroevolutionary processes. Despite their historical significance and detailed digital records, arcade games remain underexplored in cultural evolution research. Drawing on a dataset of 7,205 machines spanning four decades, we reconstruct the evolutionary trajectories of arcade niches using a multi-scale framework that integrates trait-level innovation, genre-level selection, and systemic constraints. We identify two contrasting dynamics: (1) resilient genres-such as Fighter and Driving-maintained long-term viability through innovation and collaboration networks, while (2) early Maze and Shooter subgenres collapsed due to imitation and weak collaboration. Morphospace analysis reveals how technological traits-specifically CPU speed and ROM size-co-evolved with gameplay complexity, shaping the viable design space. We argue that genres operated as evolving cultural-ecological units-structured niches that shaped trait evolution through reinforcement, constraint, and feedback. This multi-scale perspective positions arcade games as a rich model system for studying cultural macroevolution.</p>","PeriodicalId":36414,"journal":{"name":"Evolutionary Human Sciences","volume":"7 ","pages":"e30"},"PeriodicalIF":2.2,"publicationDate":"2025-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12645339/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145640810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}