Bigger is not always better: when brains get smaller.
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ABSTRACT:
SUBMITTER: Safi K
PROVIDER: S-EPMC1617168 | biostudies-literature | 2005 Sep
REPOSITORIES: biostudies-literature
Publications
Bigger is not always better: when brains get smaller.
Safi Kamran K Seid Marc A MA Dechmann Dina K N DK
Biology letters 20050901 3
Many studies assume that an increase in brain size is beneficial. However, the costs of producing and maintaining a brain are high, and we argue that brain size should be secondarily reduced by natural selection whenever the costs outweigh the benefits. Our results confirm this by showing that brain size is subject to bidirectional selection. Relative to the ancestral state, brain size in bats has been reduced in fast flyers, while it has increased in manoeuvrable flyers adapted to flight in com ...[more]
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