Birds have primate-like numbers of neurons in the forebrain

@article{Olkowicz2016BirdsHP,
  title={Birds have primate-like numbers of neurons in the forebrain},
  author={Seweryn Olkowicz and Martin Kocourek and Radek K. Lu{\vc}an and Michal Porte{\vs} and W. Tecumseh Fitch and Suzana Herculano‐Houzel and Pavel Němec},
  journal={Proceedings of the National Academy of Sciences},
  year={2016},
  volume={113},
  pages={7255 - 7260}
}
Significance Birds are remarkably intelligent, although their brains are small. Corvids and some parrots are capable of cognitive feats comparable to those of great apes. How do birds achieve impressive cognitive prowess with walnut-sized brains? We investigated the cellular composition of the brains of 28 avian species, uncovering a straightforward solution to the puzzle: brains of songbirds and parrots contain very large numbers of neurons, at neuronal densities considerably exceeding those… 

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