Coevolution of neocortical size, group size and language in humans

  title={Coevolution of neocortical size, group size and language in humans},
  author={Robin I. M. Dunbar},
  journal={Behavioral and Brain Sciences},
  pages={681 - 694}
  • Robin I. M. Dunbar
  • Published 1 December 1993
  • Psychology, Biology
  • Behavioral and Brain Sciences
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… 
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