ScienceDaily (July 15, 2010) — Mammals with larger brains in relation to body size tend to live longer. This is the conclusion reached by researchers at the Centre for Ecological Research and Forestry Applications (CREAF), affiliated to Universitat Autònoma de Barcelona, after having analysed almost 500 mammal species and obtaining new data on the relation between brain size and lifespan.
Western lowland gorilla. The brain size of some mammals is larger than expected for their body size. This is the case of large primates, such as chimpanzees and gorilla, and of whales, dolphins and elephants. (Credit: iStockphoto/Daniel Bearham)
CREAF researchers César González-Lagos and Daniel Sol, together with Simon Reader (University McGill, Canada), offer new data supporting this hypothesis in an article published recently in Journal of Evolutionary Biology. Using statistical methods, the authors analysed data from 493 mammal species -- from rodents and bats to cetaceans, felines, ungulates and marsupials -- and have reached the conclusion that having a larger brain entails having a longer life, and this represents a new advantage.
...
Read more here/Leia mais aqui: Science Daily
+++++
Journal of Evolutionary Biology
Volume 23 Issue 5, Pages 1064 - 1074
Published Online: 24 Mar 2010
C. GONZÁLEZ-LAGOS*, D. SOL*† & S. M. READER‡§
*CREAF (Centre for Ecological Research and Applied Forestries), Autonomous University of Barcelona, Bellaterra, Catalonia, Spain
†CEAB-CSIC (Centre for Advanced Studies of Blanes-Spanish National Research Council), Blanes, Catalonia, Spain
‡Behavioural Biology, Department of Biology and Helmholtz Institute, Utrecht University, Utrecht, The Netherlands
§Department of Biology, McGill University, Montréal, QC, Canada
Correspondence to Cesar González-Lagos, CREAF (Centre for Ecological Research and Applied Forestries), Autonomous University of Barcelona, Bellaterra, Catalonia E-08193, Spain. Tel.: +34 93 5868388; fax: +34 93 5814151; e-mail: c.gonzalez@creaf.uab.es
KEYWORDS
behavioural flexibility • brain evolution • cognitive buffer • lifespan • mammals • phenotypic plasticity • phylogenetic generalized linear model
ABSTRACT
Many mammals have brains substantially larger than expected for their body size, but the reasons for this remain ambiguous. Enlarged brains are metabolically expensive and require elongated developmental periods, and so natural selection should have favoured their evolution only if they provide counterbalancing advantages. [*] One possible advantage is facilitating the construction of behavioural responses to unusual, novel or complex socio-ecological challenges. This buffer effect should increase survival rates and favour a longer reproductive life, thereby compensating for the costs of delayed reproduction. Here, using a global database of 493 species, we provide evidence showing that mammals with enlarged brains (relative to their body size) live longer and have a longer reproductive lifespan. Our analysis supports and extends previous findings, accounting for the possible confounding effects of other life history traits, ecological and dietary factors, and phylogenetic autocorrelation. Thus, these findings provide support for the hypothesis that mammals counterbalance the costs of affording large brains with a longer reproductive life.
Received 3 November 2009; revised 11 February 2010; accepted 19 February 2010
DIGITAL OBJECT IDENTIFIER (DOI)10.1111/j.1420-9101.2010.01976.x
+++++
Professores, pesquisadores e alunos de universidades públicas e privadas com acesso ao site CAPES/Periódicos podem ler gratuitamente este artigo do Journal of Evolutionary Biology e de mais 22.440 publicações científicas.
+++++
NOTA CAUSTICANTE DESTE BLOGGER:
A seleção natural é um processo cego, aleatório que não prevê nada em benefício ou malefício de um ser vivo. Os autores estão atribuindo 'previdência' e providência à seleção natural para o bem-estar futuro destes mamíferos:
* natural selection should have favoured their evolution only if they provide counterbalancing advantages [a seleção natural deve ter favorecido (linguagem télica) somente se eles (os cérebros) fornecem vantagens que se contrabalançam].
Fui, nem sei por que me perguntando, será que os evolucionistas entendem mesmo de evolução???
+++++
Vote neste blog para o prêmio TOPBLOG 2010.
