Bird Speciation: Selection and the Origin of Species1

Despite the recent flurry of books addressing virtually every aspect of speciation (Schluter 2000; Coyne and Orr 2004; Gavrilets 2004), the primary literature on speciation has lately been dominated by genetics, led, many would agree, by laboratory studies on Drosophila. To many this trend is a welcome, long-awaited marriage of genomics and classical genetics, an elaboration of the foundation laid by Fisher and Dobzhansky; to others the search for “speciation genes,” driven frequently by experiments on laboratory hybrids with unclear relevance to natural situations, represents a reductionist trend conflating cause of speciation with consequence. To this latter group, the real drivers of speciation are not in the postzygotic genetics of interacting populations rebounding from allopatry, but in the prezygotic diversity of behavioral and ecological isolating factors, driven by changing environments in the great outdoors. Although largely agnostic with regard to the relevance of speciation genes, and refreshingly broad in its sampling of the literature, Speciation in Birds will come as a welcome antidote to those bemoaning the recent dominance of genetics in the study of speciation. The book’s main thesis is that the diverse relationships of birds to their natural and social environment, driven by their extraordinary capacities for dispersal, song, mating behavior, habitat specificity, and innovation, constantly place them in novel situations in which natural selection drives phenotypic, cultural, and ultimately genetic divergence. It showcases all those studies of ecological, behavioral, and organismal diversity that the liter-