Iterative adaptive radiations of fossil canids show no evidence for diversity-dependent trait evolution.

ABSTRACT: A long-standing hypothesis in adaptive radiation theory is that ecological opportunity constrains rates of phenotypic evolution, generating a burst of morphological disparity early in clade history. Empirical support for the early burst model is rare in comparative data, however. One possible reason for this lack of support is that most phylogenetic tests have focused on extant clades, neglecting information from fossil taxa. Here, I test for the expected signature of adaptive radiation using the outstanding 40-My fossil record of North American canids. Models implying time- and diversity-dependent rates of morphological evolution are strongly rejected for two ecologically important traits, body size and grinding area of the molar teeth. Instead, Ornstein-Uhlenbeck processes implying repea

SUBMITTER: Slater GJ 

PROVIDER: S-EPMC4413353 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature