Meeting Abstract
Early burst patterns of diversification have become closely linked with concepts of adaptive radiation, reflecting interest in the role of ecological opportunity in modulating diversification. But, this model has not been widely explored on coral reefs, where biodiversity is exceptional, but many lineages have high dispersal capabilities and a pan-tropical distribution. We analyze adaptive radiation in labrid fishes, arguably the most ecologically dominant and diverse radiation of fishes on coral reefs. We test for early bursts of speciation, trophic diversification, evolution in a series of functional morphological traits, and the origin of 15 functional novelties associated with feeding and locomotion. We find no evidence of early burst evolution. Instead, the pace of speciation and ecological diversification has been relatively constant, while the pace of trait evolution and the origins of functional novelties has been gradually increasing toward the present. The labrid radiation seems to have occurred in response to extensive and still increasing ecological opportunity, but within a rich community of antagonists that may have prevented abrupt diversification. Labrid diversification is closely tied to a series of substantial functional novelties that individually broadened ecological diversity, ultimately allowing them to invade virtually every trophic niche held by fishes on coral reefs.
