Discrete hierarchical organization of social group sizes.

The 'social brain hypothesis' for the evolution of large brains in primates has led to evidence for the coevolution of neocortical size and social group sizes, suggesting that there is a cognitive constraint on group size that depends, in some way, on the volume of neural material availabl...

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Main Authors: Zhou, W, Sornette, D, Hill, R, Dunbar, R
Format: Journal article
Language:English
Published: 2005
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author Zhou, W
Sornette, D
Hill, R
Dunbar, R
author_facet Zhou, W
Sornette, D
Hill, R
Dunbar, R
author_sort Zhou, W
collection OXFORD
description The 'social brain hypothesis' for the evolution of large brains in primates has led to evidence for the coevolution of neocortical size and social group sizes, suggesting that there is a cognitive constraint on group size that depends, in some way, on the volume of neural material available for processing and synthesizing information on social relationships. More recently, work on both human and non-human primates has suggested that social groups are often hierarchically structured. We combine data on human grouping patterns in a comprehensive and systematic study. Using fractal analysis, we identify, with high statistical confidence, a discrete hierarchy of group sizes with a preferred scaling ratio close to three: rather than a single or a continuous spectrum of group sizes, humans spontaneously form groups of preferred sizes organized in a geometrical series approximating 3-5, 9-15, 30-45, etc. Such discrete scale invariance could be related to that identified in signatures of herding behaviour in financial markets and might reflect a hierarchical processing of social nearness by human brains.
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spelling oxford-uuid:c27ea7f6-05a3-45d2-a0f4-b53aa5a82c0b2022-03-27T06:09:21ZDiscrete hierarchical organization of social group sizes.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:c27ea7f6-05a3-45d2-a0f4-b53aa5a82c0bEnglishSymplectic Elements at Oxford2005Zhou, WSornette, DHill, RDunbar, RThe 'social brain hypothesis' for the evolution of large brains in primates has led to evidence for the coevolution of neocortical size and social group sizes, suggesting that there is a cognitive constraint on group size that depends, in some way, on the volume of neural material available for processing and synthesizing information on social relationships. More recently, work on both human and non-human primates has suggested that social groups are often hierarchically structured. We combine data on human grouping patterns in a comprehensive and systematic study. Using fractal analysis, we identify, with high statistical confidence, a discrete hierarchy of group sizes with a preferred scaling ratio close to three: rather than a single or a continuous spectrum of group sizes, humans spontaneously form groups of preferred sizes organized in a geometrical series approximating 3-5, 9-15, 30-45, etc. Such discrete scale invariance could be related to that identified in signatures of herding behaviour in financial markets and might reflect a hierarchical processing of social nearness by human brains.
spellingShingle Zhou, W
Sornette, D
Hill, R
Dunbar, R
Discrete hierarchical organization of social group sizes.
title Discrete hierarchical organization of social group sizes.
title_full Discrete hierarchical organization of social group sizes.
title_fullStr Discrete hierarchical organization of social group sizes.
title_full_unstemmed Discrete hierarchical organization of social group sizes.
title_short Discrete hierarchical organization of social group sizes.
title_sort discrete hierarchical organization of social group sizes
work_keys_str_mv AT zhouw discretehierarchicalorganizationofsocialgroupsizes
AT sornetted discretehierarchicalorganizationofsocialgroupsizes
AT hillr discretehierarchicalorganizationofsocialgroupsizes
AT dunbarr discretehierarchicalorganizationofsocialgroupsizes