TreeBASE Search-Trees for study 11284

@ARTICLE{TreeBASE2Ref19531, author = {Cameron David Siler and Rafe M. Brown}, title = {Evidence for repeated acquisition and loss of complex characters in Southeast Asian semi-fossorial skinks}, year = {2011}, keywords = {Ancestral state reconstruction, body form evolution, Dollo?s Law, morphology, phylogeny, squamates}, doi = {}, url = {http://}, pmid = {}, journal = {Evolution}, volume = {}, number = {}, pages = {}, abstract = {Evolutionary simplification, or loss of complex characters, is a major theme in studies of body form evolution. The apparently infrequent evolutionary reacquisition of complex characters has led to the assertion (Dollo?s Law) that once lost, complex characters may be impossible to re-evolve, at least via the exact same evolutionary process. Here we provide one of the most comprehensive, fine-scale analysis of squamate body-form evolution to date, introducing a new model system of closely related lizards. Using robust molecular and morphological datasets, we conduct phylogenetic comparative analyses of morphological character change and correlation. Our phylogenetic results unambiguously support independent instances of complete limb loss as well as multiple instances of digit and external ear opening loss and re-acquisition. Even more striking, we find strong statistical support for the re-acquisition of a pentadactyl body form from a digit-reduced ancestor. Our study reveals potential thresholds in midbody width and the number of presacral vertebrae after which changes in body form take place, and shows that species of the genus Brachymeles exemplify regions of morphospace (body plans) previously undocumented in squamates. The implications are far reaching?whatever constraints have shaped the morphological evolution among lizards (excluding Bipes) have been lost in Brachymeles. The results of our study join a nascent body of literature showing strong statistical support for complex character loss, followed by evolutionary re-acquisition of complex structures associated with a generalized pentadactyl body form.} }