Evolution of brain-body allometry in Lake Tanganyika cichlids
2016 (English)In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 70, no 7, 1559-1568 p.Article in journal (Refereed) Published
Brain size is strongly associated with body size at all taxonomic levels. This relationship has been hypothesized to be an important constraint on adaptive brain size evolution. The essential assumption of this idea is that allometry has a limited ability to evolve, and that evolution of relative brain size is therefore constrained to occur along the direction of static (i.e. within species) allometry. However, recent studies have reported mixed support for this view. Here, we examine if static allometry has affected the rate of relative brain size evolution in Lake Tanganyika cichlids. The evolution of brain-body allometry showed a recent rapid divergence whereas brain size evolution represented a more gradual phenotypic divergence across the history of diversification. Accordingly, we found no support for that static allometry affected the rate of absolute or relative brain size evolution in this group. Instead, we detected low, but existing evolvability of static allometry. Moreover, static allometry evolved faster in species with relatively small and large brains than in species with medium brain size. We propose that a combination of allometric constraints and partial evolvability of static allometry have allowed for independent evolution of brain size in Lake Tanganyika cichlids. Overall, our results demonstrate a complex, yet important, role of brain-body allometry in brain size evolution.
Place, publisher, year, edition, pages
2016. Vol. 70, no 7, 1559-1568 p.
IdentifiersURN: urn:nbn:se:uu:diva-262069DOI: 10.1111/evo.12965ISI: 000380023200011PubMedID: 27241216OAI: oai:DiVA.org:uu-262069DiVA: diva2:852168
FunderHelge Ax:son Johnsons stiftelse Swedish Research Council, 621-2012-3624
Title in Thesis list of papers: Brain size evolution under allometric constraints in Lake Tanganyika cichlids2015-09-082015-09-082016-09-08Bibliographically approved