title: Song evolution, speciation, and vocal learning in passerine birds.
abstract: Phenotypic divergence can promote reproductive isolation and speciation, suggesting a possible link between rates of phenotypic evolution and the tempo of speciation at multiple evolutionary scales. To date, most macroevolutionary studies of diversification have focused on morphological traits, whereas behavioral traits─including vocal signals─are rarely considered. Thus, although behavioral traits often mediate mate choice and gene flow, we have a limited understanding of how behavioral evolution contributes to diversification. Furthermore, the developmental mode by which behavioral traits are acquired may affect rates of behavioral evolution, although this hypothesis is seldom tested in a phylogenetic framework. Here, we examine evidence for rate shifts in vocal evolution and speciation across two major radiations of codistributed passerines: one oscine clade with learned songs (Thraupidae) and one suboscine clade with innate songs (Furnariidae). We find that evolutionary bursts in rates of speciation and song evolution are coincident in both thraupids and furnariids. Further, overall rates of vocal evolution are higher among taxa with learned rather than innate songs. Taken together, these findings suggest an association between macroevolutionary bursts in speciation and vocal evolution, and that the tempo of behavioral evolution can be influenced by variation in developmental modes among lineages.
authors.affiliation: Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York, 14853.|Fuller Evolutionary Biology Program, Cornell Lab of Ornithology, Ithaca, New York, 14850.
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: Mason
authors.affiliation: Department of Biology, San Diego State University, San Diego, California, 92182.
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Burns
authors.affiliation: Department of Life Sciences, Imperial College London, Silwood Park, Ascot, SL5 7PY, United Kingdom.
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Tobias
authors.affiliation: Department of Ornithology, American Museum of Natural History, New York, New York, 10024.
authors.forename: Santiago
authors.initials: S
authors.lastname: Claramunt
authors.affiliation: Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, OX1 3PS, United Kingdom.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Seddon
authors.affiliation: Department of Ecology and Evolutionary Biology, Tulane University, New Orleans, Louisiana, 70118.
authors.forename: Elizabeth P
authors.initials: EP
authors.lastname: Derryberry
mesh_terms: D000818:Animals; D005075:Biological Evolution; D049810:Genetic Speciation; D007858:Learning; D046109:Passeriformes / Q000502:physiology; D020308:Songbirds / Q000502:physiology*; D014828:Vocalization, Animal
keywords: Bird song; diversification; learning; macroevolution; sexual selection