Vocal vs. genetic variation within species with and without vocal learning

GARCÍA NATALIA C.; CABANNE GUSTAVO SEBASTIÁN; BARREIRA ANA S.; LAVINIA OBLANCA PABLO DAMIÁN; TUBARO PABLO LUIS

Washington, DC

Congreso; VI North American Ornithology Conference; 2016

American Ornithologists? Union

Many subspecies may actually represent cryptic species, as subspecies/species delimitation needs to be reassessed through the reexamination of phenotypic variation and the incorporation of molecular information as well. Avian vocalizations are regarded as important for species delimitation, as they are involved in mate choice and can play a key role in isolating species. We analyzed intra-specific vocal variation in two passerines: the Lesser Woodcreeper (Xiphorhynchus fuscus, a suboscine) and the Blue-black Grosbeak (Cyanocompsa cyanoides, an oscine). Our objectives were to evaluate how vocal variation relates to genetic variation in species with and without song learning; and to discuss taxonomic implications, determining if vocal variation supports that at least one subspecies within each taxon should be considered as a separate species. In the Lesser Woodcreeper, we found two main types of song, one that is common to all subspecies, and one that has three geographical variants. Boundaries of these variants, subspecies and genetic clades do not fully coincide, except in the case of X. f. atlanticus. In the Blue-black Grosbeak, the most genetically divergent subspecies (C. c. rothschildii) shows clear vocal differences compared to the rest, but vocal variation among the remaining subspecies follows a clinal pattern. Thus, in both species the congruence of vocal and genetic differentiation is partial, but supports the elevation of one subspecies to the species level. Noteworthy, vocal variation showed taxonomic value in distinguishing an apparently cryptic species in both the suboscine and the oscine we studied.