Evolutionary divergence in brain size between migratory and resident birds
Sol, Daniel (Centre de Recerca Ecològica i d'Aplicacions Forestals)
Garcia-Forner, Núria (Centre de Recerca Ecològica i d'Aplicacions Forestals)
Iwaniuk, Andrew (Canadian Centre for Behavioural Neuroscience)
Davis, Katie (University of Reading. School of Biological Sciences)
Meade, Andrew (University of Glasgow. Division of Ecology and Evolutionary Biology)
Boyle, W. Alice (University of Western Ontario. Department of Biology)
Székely, Tasmás (University of Bath. Department of Biology and Biochemistry)

Date:	2010
Abstract:	Despite important recent progress in our understanding of brain evolution, controversy remains regarding the evolutionary forces that have driven its enormous diversification in size. Here, we report that in passerine birds, migratory species tend to have brains that are substantially smaller (relative to body size) than those of resident species, confirming and generalizing previous studies. Phylogenetic reconstructions based on Bayesian Markov chain methods suggest an evolutionary scenario in which some large brained tropical passerines that invaded more seasonal regions evolved migratory behavior and migration itself selected for smaller brain size. Selection for smaller brains in migratory birds may arise from the energetic and developmental costs associated with a highly mobile life cycle, a possibility that is supported by a path analysis. Nevertheless, an important fraction (over 68%) of the correlation between brain mass and migratory distance comes from a direct effect of migration on brain size, perhaps reflecting costs associated with cognitive functions that have become less necessary in migratory species. Overall, our results highlight the importance of retrospective analyses in identifying selective pressures that have shaped brain evolution, and indicate that when it comes to the brain, larger is not always better.
Grants:	Ministerio de Ciencia e Innovación CGL2007-66257 Ministerio de Ciencia e Innovación CSD2008-00040
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Subject:	Brain size ; Brain evolution ; Birds
Published in:	PloS one, Vol. 5, Issue 3 (March 2010) , p. e9617, ISSN 1932-6203

DOI: 10.1371/journal.pone.0009617
PMID: 20224776

8 p, 473.7 KB

The record appears in these collections:
Research literature > UAB research groups literature > Research Centres and Groups (research output) > Social and Legal Sciences > GRISS (Grup de Recerca en Imatge, So i Síntesi / Grupo de Investigación en Imagen, Sonido y Síntesis)
Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > CREAF (Centre de Recerca Ecològica i d'Aplicacions Forestals)
Articles > Research articles
Articles > Published articles