Why are there so many explanations for primate brain evolution?

  title={Why are there so many explanations for primate brain evolution?},
  author={Robin I. M. Dunbar and Susanne Shultz},
  journal={Philosophical Transactions of the Royal Society B: Biological Sciences},
  • Robin I. M. DunbarS. Shultz
  • Published 3 July 2017
  • Biology, Psychology
  • Philosophical Transactions of the Royal Society B: Biological Sciences
The question as to why primates have evolved unusually large brains has received much attention, with many alternative proposals all supported by evidence. We review the main hypotheses, the assumptions they make and the evidence for and against them. Taking as our starting point the fact that every hypothesis has sound empirical evidence to support it, we argue that the hypotheses are best interpreted in terms of a framework of evolutionary causes (selection factors), consequences… 

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