Meeting Abstract
Convergence of morphology and ecology is a well-described evolutionary phenomenon. Whole-animal performance capacity is a key linkage between morphology and ecology; thus one might expect convergence in morphology and ecology to also be linked to convergence in performance capacity. Previous work has demonstrated evolutionary convergence of morphology and ecology between Australian agamid lizards and North American iguanid lizards. Furthermore, several species pairs within these lineages also exhibit convergence in ecology and morphology. Therefore, we hypothesized that locomotor performance and function has converged in these groups. To test this hypothesis, we measured locomotor morphology and performance in 12 Australian agamid species and 9 North American iguanid species. We tested for convergence in function by estimating partial regression coefficients between morphology and performance using phylogenetically generalized least squares. We then assembled those coefficients into an F-matrix for each clade and tested the relationship between F-matrices. Next, we generated a performance space for all species to test clade-wide convergence. Finally, we used the Euclidean distance between species pairs in the performance space coupled with evolutionary simulations to test for transcontinental convergence of performance for each species pair. We found that Australian agamids and North American iguanids occupy similar regions of performance space and that several species pairs have converged in locomotor performance. However, F-matrices were not related suggesting that the functional link between morphology and performance has evolved differently in these lizard clades.
