The importance of global parsimony and historical bias in understanding tetrapod evolution. Part II. Vertebral centrum, costal ventilation, and paedomorphosis

A recent phylogenetic analysis based on a data matrix of 43 taxa and 155 osteological characters has produced a new hypothesis of tetrapod phylogeny that is drastically different from the established consensus. This phylogeny indicates that the centrum of lissamphibians is apparently a pleurocentrum, and is homologous with the centrum of amniotes. The interpretation of the dental characters that have been used to argue for close relationships between lissamphibians and some dissorophoids is more complex and difficult than has been often been suggested. If paedomorphosis was an important process in the origin of lissamphibians, it may have occurred earlier than previously suggested because lepospondyls can be interpreted as paedomorphic stegocephalians.