Evolution in the Social Brain

@article{Dunbar2007EvolutionIT,
  title={Evolution in the Social Brain},
  author={Robin I. M. Dunbar and Susanne Shultz},
  journal={Science},
  year={2007},
  volume={317},
  pages={1344 - 1347}
}
The evolution of unusually large brains in some groups of animals, notably primates, has long been a puzzle. Although early explanations tended to emphasize the brain's role in sensory or technical competence (foraging skills, innovations, and way-finding), the balance of evidence now clearly favors the suggestion that it was the computational demands of living in large, complex societies that selected for large brains. However, recent analyses suggest that it may have been the particular… 
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  • 2007
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Research in the field and laboratory shows that sophisticated social cognition underlies social behavior in primate groups and a growing body of evidence suggests that the quality of social relationships has measurable fitness consequences for individuals.
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It is argued that future work aiming to understand how animal behavior, cognition, and brains are shaped by the environment should focus on brain functions and identify neural circuitry correlates of social tasks, not only brain sizes.
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  • 2013
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It is argued that ravens represent a promising case for testing the idea that sophisticated social cognition may evolve in systems with a given degree of social complexity, independently of phylogeny.
Explaining brain size variation: from social to cultural brain
TLDR
This work proposes to integrate the social brain hypothesis into a broader framework the authors call cultural intelligence, which stresses the importance of the high costs of brain tissue, general behavioral flexibility and the role of social learning in acquiring cognitive skills.
Sociality does not drive the evolution of large brains in eusocial African mole-rats
TLDR
The results show that the challenges coupled with sociality in this group of rodents do not require brain enlargement or fundamental reorganization, and suggest that group living or pair bonding per se does not select strongly for brain enlargements unless coupled with Machiavellian interactions affecting individual fitness.
Revisiting the cognitive buffer hypothesis for the evolution of large brains
  • D. Sol
  • Biology, Medicine
    Biology Letters
  • 2008
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Evidence in birds and mammals is accumulating that a large brain facilitates the construction of novel and altered behavioural patterns and that this ability helps dealing with new ecological challenges more successfully, supporting the cognitive-buffer interpretation of the evolution of large brains.
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