My interests lie in the very broad areas of the evolutionary biology of birds, and of other vertebrates to a lesser degree.  My research covers several areas.  1) Phylogeny reconstruction - the genealogical relationships of organisms to one another.  I concentrate on deciphering interfamilial and interordinal relationships.  Recently, we discovered molecular genetic evidence that neoavian birds are comprised of two major groups that have evolved in parallel, much like marsupial and placental mammals.  These data imply that at least five traditionally recognized orders of birds are polyphyletic, with member families in each of the two groups, and mistaken to be related on the basis of convergent morphologies.  2) Biogeography - the correlation of patterns of phyletic divergence and the origins of new taxa to the geographic distribution of species and the formation of geophysical barriers through time.  Some researchers conjecture that groups of birds with modern endemism to southern continents must have originated there during the Cretaceous when those continents were united.  However, among the orders of fossil birds I have described are the sister group to modern ratites, Lithornithiformes, and a primitive ostrich, Palaeotis, whose Northern Hemisphere distributions are quite inconsistent with those of their modern southern relatives.  Similarly, our molecular genetic data show that various "gruiform" birds with southern disjunct endemism (e.g., kagu-sunbittern, or the pantropical finfoot family) are too closely related to have diverged in the Cretaceous.  Indeed, fossils suggest that these dispersed through the Northern Hemisphere during the Cenozoic, instead.   3) Macroevolution - the plasticity and polarity of morphological evolution within lineages.  This is best understood by exploring pattern in the distribution of morphological characters that are superimposed onto a phylogenetic "tree" inferred independently from molecular genetic analysis.  4) Evolutionary rate - how rates of genetic and morphological evolution differ within and between taxa.  I address these diverse problems through the combined study of fossil vertebrates, comparative anatomy (particularly osteology), DNA sequencing, and DNA hybridization. 

                I welcome inquiries from prospective graduate students who are interested in integrating diverse classical and modern disciplines to address the systematics and macroevolution of any taxonomic group of organisms.  I have separate laboratories devoted to paleontological and molecular studies.  Among our department's natural history museums are comparative vertebrate collections for use in research and education.

Courses Regularly Offered

    Human Anatomy

                                                                                                                               The Vertebrate Museum

                                                                                                                                The whale is now on permanent public display! (link here)