Robert M. Zink, a leading scholar in avian evolution, holds the Breckenridge Chair in Ornithology and has served as Curator of Birds at the Bell Museum of Natural History and as Professor of Ecology, Evolution, and Behavior at the University of Minnesota. Among the recurrent themes in his work are the tempo of avian diversification and speciation, species limits, phylogeny, and comparative phylogeography. Two areas deserve special mention. First is his role in creating a vigorous dialogue concerning the theory and practice of ranking taxa at the species and subspecies levels. In this debate, which has permeated ornithological thinking for more than a century, Professor Zink and co-authors have articulated the advantages and disadvantages of the phylogenetic species concept in both theoretical and applied situations. He has been forthright in throwing down the gauntlet to challenge how current subspecific categories are being used (and misused) in conservation biology.

The second is the use of new technologies and analytical approaches in studying geographic variation. The discipline of phylogeography— focused at the interface of population genetics and systematic biology—is central to efforts to understand the origin and maintenance of biotic diversity. Professor Zink adopted this approach with his studies of Fox Sparrows (Passerella iliaca), which eventually incorporated information on plumage, skeletal morphology, and mitochondrial DNA (mtDNA). This is probably the most comprehensive documentation in any bird species group. His use of multiple character systems serves as a template for modern studies of geographic variation.

He has also been instrumental in questioning the role of Late Pleistocene glaciations in the origins of many North American species, a subject that has recently been extended to Europe and Asia. His comparisons of phylogeographic structures of codistributed species have provided new insights into the evolutionary diversification of avian communities.

Professor Zink’s work has been crucial in introducing new ideas to a wide audience. He continues a long tradition of ornithologists who have provided intellectual leadership in ornithology and in the larger community of evolutionary biologists. For his significant and continuing contribution to avian systematics, phylogeny, phylogeography, speciation theory, and conservation, the American Ornithologists’ Union presents Robert M. Zink with the William Brewster Memorial Award for 2005.