Development, trends and phylogenetic inference

Abstract

An analysis of the development and history of theearly tetrapod limb and cranium is used to examine phylogenetic inference, recapitulatory and other developmental hypotheses. The use of recapitulatory ontogenetic hypotheses in phylogenetic inference is questioned by modern aspects of embryological studies, because the developmental patterns may evolve by omitting or modifying ontogenetic stages. Fossil taxa play an important role in the reconstruction of hypothetical transformation series. Furthermore an understanding of patterns of development is important in aiding the interpretation of transformation series such as in the evolution of the tretrapod limb. There is need for more complete theories of phylogenetic relationships among and within clades, so as to determine the limits set by developmental mechanisms, biomechanics and history.