Previous articleNext article Free2008 American Society of Naturalists Awards Sewall Wright AwardSpencer BarrettJanis AntonovicsJanis AntonovicsUniversity of Virginia Search for more articles by this author University of VirginiaPDFPDF PLUSFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinked InRedditEmailQR Code SectionsMoreIn 2008, the American Society of Naturalists honored Spencer Barrett with the Sewall Wright Award, which recognizes an active midcareer or senior investigator who has made major contributions to the conceptual unification of the biological sciences. Spencer Barrett has contributed enormously to our understanding of the forces driving evolutionary transitions in plant mating systems. He has carried out extensive field studies on the evolution of selfing, dioecy, and mechanisms involved in pollen donation, receipt, and mating compatibility. This work has greatly broadened our understanding of floral evolution, the origins of dioecy, and the evolution of plant breeding systems. He has elegantly shown that floral characteristics can evolve through mechanisms that increase the efficiency of pollen transmission or receipt as well as through mechanisms that regulate different levels of outcrossing.In the true tradition of Sewall Wright, he has shown that knowledge of both genetics and population substructuring are absolute prerequisites for understanding the evolution of mating systems. His work on the evolution of floral polymorphism in water hyacinths is a tour de force showing how population differences are determined by the direct interplay of pollinator activity, the magnitude of genetic drift in founding populations, and the underlying genetics of the polymorphism. This work on the pathways of breakdown of tristyly to different distylous and monomorphic populations constitutes perhaps the most complete example of the real‐world operation of processes central to Sewall Wright’s shifting balance theory. He has also made important contributions to our understanding of species invasions, especially the idea that these invasions are likely to be accompanied by substantial genetic change. Indeed, this pioneering work was crucial in bringing the impact of plant invasions to the forefront of the consciousness of biologists and the general public.Spencer Barrett is a Fellow of the Royal Society of London, a Fellow of the Royal Society of Canada, and a recipient of a Merit Award from the Botanical Society of America. Recently, he received the Lawson Medal from the Canadian Botanical Association in recognition of his lifetime contributions to Canadian botany. He has also been a recipient of an outstanding teacher award at the University of Toronto and has mentored numerous graduate students and postdocs who are now leading researchers throughout the world. Throughout his research, he has combined a thorough mix of field observations, experiments, and theory, all of which have been strongly grounded in a broad knowledge of natural history. He incorporates rigor and imagination, combines theory with empiricism, and has a breadth that reflects a true integration of population genetics, ecology, systematics, and applied biology. For these many reasons, the American Society of Naturalists considers him to be an ideal recipient of the Sewall Wright Award. Previous articleNext article DetailsFiguresReferencesCited by The American Naturalist Volume 173, Number 1January 2009 Published for The American Society of Naturalists Article DOIhttps://doi.org/10.1086/593708 Views: 266Total views on this site © 2008 by The University of Chicago.PDF download Crossref reports no articles citing this article.