Open AccessSexual selection impacts brain anatomy in frogs and toads
Author(s) -
Zeng Yu,
Lou Shang Ling,
Liao Wen Bo,
Jehle Robert,
Kotrschal Alexander
Publication year - 2016
Publication title -
ecology and evolution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.17
H-Index - 63
ISSN - 2045-7758
DOI - 10.1002/ece3.2459
Subject(s) - sexual selection , biology , brain size , courtship , cerebrum , evolutionary biology , mate choice , brain morphometry , selection (genetic algorithm) , zoology , sexual dimorphism , natural selection , vertebrate , courtship display , mating , neuroscience , central nervous system , gene , genetics , medicine , artificial intelligence , computer science , magnetic resonance imaging , radiology
Natural selection is a major force in the evolution of vertebrate brain size, but the role of sexual selection in brain size evolution remains enigmatic. At least two opposing schools of thought predict a relationship between sexual selection and brain size. Sexual selection should facilitate the evolution of larger brains because better cognitive abilities may aid the competition for mates. However, it may also restrict brain size evolution due to energetic trade‐offs between brain tissue and sexually selected traits. Here, we examined the patterns of selection on brain size and brain anatomy in male anurans (frogs and toads), a group where the strength of sexual selection differs markedly among species, using a phylogenetically controlled generalized least‐squared ( PGLS ) regression analyses. The analysis revealed that in 43 Chinese anuran species, neither mating system, nor type of courtship, or testes mass was significantly associated with relative brain size. While none of those factors related to the relative size of olfactory nerves, optic tecta, telencephalon, and cerebellum, the olfactory bulbs were relatively larger in monogamous species and those using calls during courtship. Our findings support the mosaic model of brain evolution and suggest that while the investigated aspects of sexual selection do not seem to play a prominent role in the evolution of brain size of anurans, they do impact their brain anatomy.