Data from: Phenotypic covariation and morphological diversification in the ruminant skull

Differences among clades in their diversification patterns result from a
combination of extrinsic and intrinsic factors. In this study I examined
the role of intrinsic factors in the morphological diversification of
ruminants in general, and in the differences between bovids and cervids in
particular. Using skull morphology, which embodies many of the adaptations
that distinguish bovids and cervids, I examined 132 of the 200 extant
ruminant species. As a proxy for intrinsic constraints I quantified
different aspects of the phenotypic covariation structure within species,
and compared them with the among-species divergence patterns, using
phylogenetic comparative methods. My results show that for most species,
divergence is well aligned with their phenotypic covariance matrix, and
those that are better aligned have diverged further away from their
ancestor. Bovids have dispersed into a wider range of directions in
morphospace than cervids, and their overall disparity is higher. This
difference is best explained by the lower eccentricity of bovids'
within-species covariance matrices. These results are consistent with the
role of intrinsic constraints in determining amount, range, and direction
of dispersion, and demonstrate that intrinsic constraints can influence
macroevolutionary patterns even as the covariance structure evolves.