ALL BIRDS BARCODING INITIATIVE (ABBI): BUILDING AN ATLAS OF AVIAN MITOCHONDRIAL DNA DIVERSITY

STOECKLE, M.; BAKER, A. J.; KERR, K. C. R.; LIFJELD, J. T.; LIJTMAER, D. A.; ERICSON, P.; TUBARO, P. L.

Adelaida

Congreso; Fourth International Barcode of Life Conference; 2011

University of Adelaide - Consortium for the Barcode of Life

As of September 2011, researchers have deposited over 25,000 barcode records representing over 3,800 species, more than 1/3 of world birds. Results so far strongly confirm the early observation that most bird species are comprised of a single cluster of mtDNA, distinct from those of other species. Most of the discordant cases reflect secondary mixing among recently diverged forms. Among well-sampled Nearctic and Palearctic families, about 10% of species comprise two or more clusters that differ by geographic range. The proportion with geographic clusters appears to be higher in other biogeographic regions. Extrapolating from current taxonomic practice predicts that most such clusters will eventually be recognized as distinct species. Setting aside geographic and hybrid clusters, intraspecific mitochondrial diversity is uniformly low and only faintly related to census population size. Most of the remaining intraspecific differences are due to singleton variants, which differ biologically from shared variants. Higher-level taxonomic divisions are visible as discontinuities in a Klee diagram of COI indicator vector correlations. The observed discontinuities demonstrate clustering at multiple evolutionary scales and imply that most living birds are part of recent radiations. With community involvement, the growing database of barcode records can become an increasingly accurate atlas of avian mitochondrial diversity, with practical and scientific uses for collections managers, researchers, and those interested in identifying birds from fragmentary specimens. A global avian barcode atlas is likely to provide new insights into population biology, speciation, and deeper evolutionary processes.