The origins of human cumulative culture: from the foraging niche to collective intelligence

Various studies have investigated cognitive mechanisms underlying culture in humans and other great apes. However, the adaptive reasons for the evolution of uniquely sophisticated cumulative culture in our species remain unclear. We propose that the cultural capabilities of humans are the evolutionary result of a stepwise transition from the ape-like lifestyle of earlier hominins to the foraging niche still observed in extant hunter–gatherers. Recent ethnographic, archaeological and genetic studies have provided compelling evidence that the components of the foraging niche (social egalitarianism, sexual and social division of labour, extensive co-residence and cooperation with unrelated individuals, multilocality, fluid sociality and high between-camp mobility) engendered a unique multilevel social structure where the cognitive mechanisms underlying cultural evolution (high-fidelity transmission, innovation, teaching, recombination, ratcheting) evolved as adaptations. Therefore, multilevel sociality underlies a ‘social ratchet’ or irreversible task specialization splitting the burden of cultural knowledge across individuals, which may explain why human collective intelligence is uniquely able to produce sophisticated cumulative culture. The foraging niche perspective may explain why a complex gene-culture dual inheritance system evolved uniquely in humans and interprets the cultural, morphological and genetic origins of Homo sapiens as a process of recombination of innovations appearing in differentiated but interconnected populations. This article is part of a discussion meeting issue ‘The emergence of collective knowledge and cumulative culture in animals, humans and machines’

Comparing emotion inferences from dogs (Canis familiaris), panins (Pan troglodytes/Pan paniscus), and humans (Homo sapiens) facial displays

Human beings are highly familiar over-learnt social targets, with similar physical facial morphology between perceiver and target. But does experience with or similarity to a social target determine whether we can accurately infer emotions from their facial displays? Here, we test this question across two studies by having human participants infer emotions from facial displays of: dogs, a highly experienced social target but with relatively dissimilar facial morphology; panins (chimpanzees/bonobos), inexperienced social targets, but close genetic relatives with a more similar facial morphology; and humans. We find that people are more accurate inferring emotions from facial displays of dogs compared to panins, though they are most accurate for human faces. However, we also find an effect of emotion, such that people vary in their ability to infer different emotional states from different species' facial displays, with anger more accurately inferred than happiness across species, perhaps hinting at an evolutionary bias towards detecting threat. These results not only compare emotion inferences from human and animal faces but provide initial evidence that experience with a non-human animal affects inferring emotion from facial displays

Frontal White Matter Volume Is Associated with Brain Enlargement and Higher Structural Connectivity in Anthropoid Primates

Previous research has indicated the importance of the frontal lobe and its ‘executive’ connections to other brain structures as crucial in explaining primate neocortical adaptations. However, a representative sample of volumetric measurements of frontal connective tissue (white matter) has not been available. In this study, we present new volumetric measurements of white and grey matter in the frontal and non-frontal neocortical lobes from 18 anthropoid species. We analyze this data in the context of existing theories of neocortex, frontal lobe and white versus grey matter hyperscaling. Results indicate that the ‘universal scaling law’ of neocortical white to grey matter applies separately for frontal and non-frontal lobes; that hyperscaling of both neocortex and frontal lobe to rest of brain is mainly due to frontal white matter; and that changes in frontal (but not non-frontal) white matter volume are associated with changes in rest of brain and basal ganglia, a group of subcortical nuclei functionally linked to ‘executive control’. Results suggest a central role for frontal white matter in explaining neocortex and frontal lobe hyperscaling, brain size variation and higher neural structural connectivity in anthropoids

The Temporal Requirements for Insulin Signaling During Development in Drosophila

Recent studies have indicated that the insulin-signaling pathway controls body and organ size in Drosophila, and most metazoans, by signaling nutritional conditions to the growing organs. The temporal requirements for insulin signaling during development are, however, unknown. Using a temperature-sensitive insulin receptor (Inr) mutation in Drosophila, we show that the developmental requirements for Inr activity are organ specific and vary in time. Early in development, before larvae reach the “critical size” (the size at which they commit to metamorphosis and can complete development without further feeding), Inr activity influences total development time but not final body and organ size. After critical size, Inr activity no longer affects total development time but does influence final body and organ size. Final body size is affected by Inr activity from critical size until pupariation, whereas final organ size is sensitive to Inr activity from critical size until early pupal development. In addition, different organs show different sensitivities to changes in Inr activity for different periods of development, implicating the insulin pathway in the control of organ allometry. The reduction in Inr activity is accompanied by a two-fold increase in free-sugar levels, similar to the effect of reduced insulin signaling in mammals. Finally, we find that varying the magnitude of Inr activity has different effects on cell size and cell number in the fly wing, providing a potential linkage between the mode of action of insulin signaling and the distinct downstream controls of cell size and number. We present a model that incorporates the effects of the insulin-signaling pathway into the Drosophila life cycle. We hypothesize that the insulin-signaling pathway controls such diverse effects as total developmental time, total body size and organ size through its effects on the rate of cell growth, and proliferation in different organs

Geographical and social isolation drive the evolution of Austronesian languages.

The origins of linguistic diversity remain controversial. Studies disagree on whether group features such as population size or social structure accelerate or decelerate linguistic differentiation. While some analyses of between-group factors highlight the role of geographical isolation and reduced linguistic exchange in differentiation, others suggest that linguistic divergence is driven primarily by warfare among neighbouring groups and the use of language as marker of group identity. Here we provide the first integrated test of the effects of five historical sociodemographic and geographic variables on three measures of linguistic diversification among 50 Austronesian languages: rates of word gain, loss and overall lexical turnover. We control for their shared evolutionary histories through a time-calibrated phylogenetic sister-pairs approach. Results show that languages spoken in larger communities create new words at a faster pace. Within-group conflict promotes linguistic differentiation by increasing word loss, while warfare hinders linguistic differentiation by decreasing both rates of word gain and loss. Finally, we show that geographical isolation is a strong driver of lexical evolution mainly due to a considerable drift-driven acceleration in rates of word loss. We conclude that the motor of extreme linguistic diversity in Austronesia may have been the dispersal of populations across relatively isolated islands, favouring strong cultural ties amongst societies instead of warfare and cultural group marking

Development of social learning and play in BaYaka hunter-gatherers of Congo.

High-fidelity transmission of information through imitation and teaching has been proposed as necessary for cumulative cultural evolution. Yet, it is unclear when and for which knowledge domains children employ different social learning processes. This paper explores the development of social learning processes and play in BaYaka hunter-gatherer children by analysing video recordings and time budgets of children from early infancy to adolescence. From infancy to early childhood, hunter-gatherer children learn mainly by imitating and observing others' activities. From early childhood, learning occurs mainly in playgroups and through practice. Throughout childhood boys engage in play more often than girls whereas girls start foraging wild plants from early childhood and spend more time in domestic activities and childcare. Sex differences in play reflect the emergence of sexual division of labour and the play-work transition occurring earlier for girls. Consistent with theoretical models, teaching occurs for skills/knowledge that cannot be transmitted with high fidelity through other social learning processes such as the acquisition of abstract information e.g. social norms. Whereas, observational and imitative learning occur for the transmission of visually transparent skills such as tool use, foraging, and cooking. These results suggest that coevolutionary relationships between human sociality, language and teaching have likely been fundamental in the emergence of human cumulative culture

Inclusive fitness for in-laws

A.G. is supported by a Natural Environment Research Council Independent Research Fellowship (NE/K009524/1) and a European Research Council Consolidator Grant (771387)Cooperation among kin is common across the natural world and can be explained in terms of inclusive fitness theory, which holds that individuals can derive indirect fitness benefits from aiding genetically related individuals. However, human kinship includes not only genetic kin but also kin by marriage: our affines (in-laws) and spouses. Can cooperation between these genetically unrelated kin be reconciled with inclusive fitness theory? Here, we argue that although affinal kin and spouses do not necessarily share genetic ancestry, they may have shared genetic interests in future reproduction and, as such, can derive indirect fitness benefits though cooperating. We use standard inclusive fitness theory to derive a coefficient of shared reproductive interest (s) that predicts altruistic investment both in genetic kin and in spouses and affines. Specifically, a behaviour that reduces the fitness of the actor by c and increases the fitness of the recipient by b will be favoured by natural selection when sb > c. We suggest that the coefficient of shared reproductive interest may provide a valuable tool for understanding not only the evolution of human kinship but also cooperation and conflict across the natural world more generally.Publisher PDFPeer reviewe

Salubridade ambiental e sua relação com o saneamento básico e aspecos socioeconômicos: Environmental health and its relationship with basic sanitation and socioeconomic aspects

O desenvolvimento econômico das últimas décadas promoveu uma grande concentração de população nas zonas urbanas, em áreas geralmente ocupadas sem o devido planejamento ambiental e urbano, expondo os cidadãos a uma infraestrutura deficitária em vários aspectos, especialmente aqueles relacionados ao saneamento básico, trazendo como consequência uma série de impactos ao meio ambiente, à saúde e a qualidade de vida da população, podendo inclusive tornar tais espaços insalubres aos seres humanos. A salubridade ambiental pode ser entendida como um o conjunto de medidas que visam promover a saúde pública coletiva e preventiva, por meio da redução do contato com doenças relacionadas ao saneamento básico inadequado que possam ocasionar danos ao bem-estar físico, mental e social da população. Sabe-se que as interações entre os seres humanos e o meio ambiente natural e urbano são muito complexas, contemplando uma série de variáveis e condicionantes e, por essa razão, são utilizados indicadores capazes de agrupar dados de diferentes naturezas em informações simples e úteis, suficientes para proporcionar diagnósticos e subsidiar ações de melhoria. Nesse sentido, essa pesquisa objetiva elencar os principais aspectos relacionados à salubridade ambiental, aprofundando no estudo do Indicador de Salubridade Ambiental (ISA), proposto pelo Conselho Estadual de Saneamento de São Paulo, evidenciando sua metodologia, subindicadores, resultados de aplicações e as principais vantagens da sua utilização.O desenvolvimento econômico das últimas décadas promoveu uma grande concentração de população nas zonas urbanas, em áreas geralmente ocupadas sem o devido planejamento ambiental e urbano, expondo os cidadãos a uma infraestrutura deficitária em vários aspectos, especialmente aqueles relacionados ao saneamento básico, trazendo como consequência uma série de impactos ao meio ambiente, à saúde e a qualidade de vida da população, podendo inclusive tornar tais espaços insalubres aos seres humanos. A salubridade ambiental pode ser entendida como um o conjunto de medidas que visam promover a saúde pública coletiva e preventiva, por meio da redução do contato com doenças relacionadas ao saneamento básico inadequado que possam ocasionar danos ao bem-estar físico, mental e social da população. Sabe-se que as interações entre os seres humanos e o meio ambiente natural e urbano são muito complexas, contemplando uma série de variáveis e condicionantes e, por essa razão, são utilizados indicadores capazes de agrupar dados de diferentes naturezas em informações simples e úteis, suficientes para proporcionar diagnósticos e subsidiar ações de melhoria. Nesse sentido, essa pesquisa objetiva elencar os principais aspectos relacionados à salubridade ambiental, aprofundando no estudo do Indicador de Salubridade Ambiental (ISA), proposto pelo Conselho Estadual de Saneamento de São Paulo, evidenciando sua metodologia, subindicadores, resultados de aplicações e as principais vantagens da sua utilização

As relacões entre eco-inovações e o impacto na performance empresarial: uma pesquisa empíricana indústria têxtil brasileira

This study draws from the resource-based theory and investigates the interrelationships between three types of eco-innovation (process, product, organizational) and their impact on business performance. Using a structural equation design with 70 samples collected from textile industry, research results show that business performance is affected by product and organizational eco-innovations. The process and product eco-innovations significantly influence the effects of organizational eco-innovation, and there are connections between process and product eco-innovations. Research reveals that each type of eco-innovation has its own attributes, determinants, and contributions to business performance. Study on the textile sector broadens the discussion of interdependence and co-evolutionary relationships among different types of eco-innovation and demonstrates that the development of efficient innovation programs requires a holistic view and organizational and technological capabilities.En este trabajo se utiliza la teoría basada en los recursos y se estudian las interrelaciones entre tres tipos de ecoinnovación (proceso, producto, organizacional) y su impacto en el desempeño empresarial. Se utilizan modelos de ecuaciones estructurales, con una muestra de 70 empresas del sector textil. Los resultados indican que el desempeño corporativo es afectado por las ecoinnovaciones de producto y ecoinnovaciones organizacionales. La ecoinnovación organizacional influye significativamente en los efectos de las ecoinnovaciones de proceso y de producto. Además, existen relaciones entre las ecoinnovaciones de procesos y de productos. Se sugiere que cada tipo de ecoinnovación tiene sus propios atributos y determinantes, y que contribuye positivamente al desempeño de la empresa. El estudio en la industria textil profundiza el debate sobre la interdependencia de las relaciones coevolutivas entre los distintos tipos de ecoinnovación, y demuestra que el desarrollo de programas de innovación eficientes requiere el perfeccionamiento de las capacidades organizacionales y tecnológicas.Este estudo usa a teoria baseada em recursos e investiga as inter-relações entre três tipos de ecoinovação (processo, produto, organizacional) e o seu impacto na performance empresarial. Com o uso de uma modelagem de equações estruturais e com uma amostra que envolveu 70 empresas têxteis, os resultados da pesquisa indicam que a performance empresarial é afetada por ecoinovações de produto e ecoinovações organizacionais. A ecoinovação organizacional influencia significativamente os efeitos das ecoinovações de processo e de produto e existem relações entre as ecoinovações de processos e de produtos. A pesquisa revela que cada tipo de ecoinovação tem seus próprios atributos e determinantes e que contribuem positivamente para a performance empresarial. O estudo no setor têxtil amplia a discussão sobre a interdependência das relações coevolutivas entre os diferentes tipos de ecoinovação e demonstra que o desenvolvimento de programas de inovação eficientes requerem o aprimoramento das capacidades organizacionais e tecnológicas

As relacões entre eco-inovações e o impacto na performance empresarial: uma pesquisa empíricana indústria têxtil brasileira

This study draws from the resource-based theory and investigates the interrelationships between three types of eco-innovation (process, product, organizational) and their impact on business performance. Using a structural equation design with 70 samples collected from textile industry, research results show that business performance is affected by product and organizational eco-innovations. The process and product eco-innovations significantly influence the effects of organizational eco-innovation, and there are connections between process and product eco-innovations. Research reveals that each type of eco-innovation has its own attributes, determinants, and contributions to business performance. Study on the textile sector broadens the discussion of interdependence and co-evolutionary relationships among different types of eco-innovation and demonstrates that the development of efficient innovation programs requires a holistic view and organizational and technological capabilities.En este trabajo se utiliza la teoría basada en los recursos y se estudian las interrelaciones entre tres tipos de ecoinnovación (proceso, producto, organizacional) y su impacto en el desempeño empresarial. Se utilizan modelos de ecuaciones estructurales, con una muestra de 70 empresas del sector textil. Los resultados indican que el desempeño corporativo es afectado por las ecoinnovaciones de producto y ecoinnovaciones organizacionales. La ecoinnovación organizacional influye significativamente en los efectos de las ecoinnovaciones de proceso y de producto. Además, existen relaciones entre las ecoinnovaciones de procesos y de productos. Se sugiere que cada tipo de ecoinnovación tiene sus propios atributos y determinantes, y que contribuye positivamente al desempeño de la empresa. El estudio en la industria textil profundiza el debate sobre la interdependencia de las relaciones coevolutivas entre los distintos tipos de ecoinnovación, y demuestra que el desarrollo de programas de innovación eficientes requiere el perfeccionamiento de las capacidades organizacionales y tecnológicas.Este estudo usa a teoria baseada em recursos e investiga as inter-relações entre três tipos de ecoinovação (processo, produto, organizacional) e o seu impacto na performance empresarial. Com o uso de uma modelagem de equações estruturais e com uma amostra que envolveu 70 empresas têxteis, os resultados da pesquisa indicam que a performance empresarial é afetada por ecoinovações de produto e ecoinovações organizacionais. A ecoinovação organizacional influencia significativamente os efeitos das ecoinovações de processo e de produto e existem relações entre as ecoinovações de processos e de produtos. A pesquisa revela que cada tipo de ecoinovação tem seus próprios atributos e determinantes e que contribuem positivamente para a performance empresarial. O estudo no setor têxtil amplia a discussão sobre a interdependência das relações coevolutivas entre os diferentes tipos de ecoinovação e demonstra que o desenvolvimento de programas de inovação eficientes requerem o aprimoramento das capacidades organizacionais e tecnológicas