morphological diversity and the roles of contingency, chance and determinism in african cichlid radiations形态多样性和应急的角色,机会和决定论在非洲的丽鱼科鱼的辐射.pdfVIP

Morphological Diversity and the Roles of Contingency, Chance and Determinism in African Cichlid Radiations Kyle A. Young1,2*, Jos Snoeks3,4, Ole Seehausen1,2 1 Department of Aquatic Ecology Evolution, Institute of Ecology Evolution, University of Bern, Bern, Switzerland, 2 EAWAG, Centre of Ecology, Evolution Biogeochemistry, Kastanienbaum, Switzerland, 3 Zoology Department, Royal Museum for Central Africa, Tervuren, Belgium, 4 Department of Biology, University of Leuven, Leuven, Belgium Abstract Background: Deterministic evolution, phylogenetic contingency and evolutionary chance each can influence patterns of morphological diversification during adaptive radiation. In comparative studies of replicate radiations, convergence in a common morphospace implicates determinism, whereas non-convergence suggests the importance of contingency or chance. Methodology/Principal Findings: The endemic cichlid fish assemblages of the three African great lakes have evolved similar sets of ecomorphs but show evidence of non-convergence when compared in a common morphospace, suggesting the importance of contingency and/or chance. We then analyzed the morphological diversity of each assemblage independently and compared their axes of diversification in the unconstrained global morphospace. We find that despite differences in phylogenetic composition, invasion history, and ecological setting, the three assemblages are diversifying along parallel axes through morphospace and have nearly identical variance-covariance structures among morphological elements. Conclusions/Significance: By demonstrating that replicate adaptive radiations are diverging along parallel axes, we have shown that non-convergence in the common morphospace is associated with convergence in the global mor