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Coevolution of neocortical size, group size and language in humans

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Abstract

Group size covaries with relative neocortical volume in nonhuman primates. This regression equation predicts a group size for modern humans very similar to that for hunter-gatherer and traditional horticulturalist societies. Similar group sizes are found in other contemporary and historical societies. Nonhuman primates maintain group cohesion through social grooming; among the Old World monkeys and apes, social grooming time is linearly related to group size. Maintaining stability of human-sized groups by grooming alone would make intolerable time demands. It is therefore suggested (1) that the evolution of large groups in the human lineage depended on developing a more efficient method for time-sharing the processes of social bonding and (2) that language uniquely fulfills this requirement. Data on the size of conversational and other small interacting groups of humans accord with the predicted relative efficiency of conversation compared to grooming as a bonding process. In human conversations about 60% of time is spent gossiping about relationships and personal experiences. Language may accordingly have evolved to allow individuals to learn about the behavioural characteristics of other group members more rapidly than was feasible by direct observation alone.
... Según Hansen y Reich (2015), los participantes de los cursos MOOCs viven en colonias prósperas y educadas. Por otro lado, Dunbar (1993) menciona que existe un límite cognitivo para el número de personas (150) con el cual un individuo puede establecer y mantener relaciones estables. ...
... We must of course bear in mind the innate differences between human and animal data, albeit both species being mammalian. There has been much controversy in the social networks field about these figures [17][18][19][37][38][39][40]. However, they have not been discussed in the biomedical literature. ...
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... Without the introduction of a division of power within an organisation it is not possible to introduce a special type of "ecological" or "holonic" network governance found univerally in social animals (Dunbar 1993). Ecological governance is based on decentralisation as found in the human brain to allow redundancy and so resiliency. ...
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... In this case, the new unit of selection (termed a 'sociont') would consist of integrated and adapted cultural lifestyles, coextensive with (but not identical to) the social limits of underpinning hominin communities (based on face-to-face contacts, and congruous with Pan communities today; e.g. [54][55][56]). While not the first proposition that an ETI (in some shape or form) is responsible for the evolution of our unusual species (see e.g. ...
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... This is a problem because it is difficult to handle complexity. A popular observation, known as Dunbar's number (Dunbar 1993;2002;, proposes that communities tend not to exceed 150 members, at least communities of primates and groups under certain conditions. Similar size thresholds can be observed for human communities. ...
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... Today, the majority of humans live in cities and urbanization has fundamentally changed the living conditions of humanity. Humans have lived for most of our evolutionary history in small bands of approximately 150 individuals, with individuals integrated into tight family networks [1]. Cities by definition have a higher concentration of genetically unrelated people and may make lonelinessthe feeling of unwanted isolation -particularly salient. ...
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