Molecular Phylogenetics of Diurnal Birds of Prey in the Avian Accipitridae Family.

Abstract

The avian family Accipitridae includes 240 species and 60 genera of hawks, eagles, Old World vultures, kites, accipiters, goshawks and harriers. Phylogeny for Accipitridae has been difficult to resolve with morphological data such that non-monophyly of subfamilies and genera was suspected. This study used mitochondrial and nuclear sequence data to resolve the phylogeny for Accipitridae taxa. Extensive sampling of nominal species and genera (75% of all species and 97% of genera) identified non-monophyly for most genera and subfamilies/subgroups and some species. Monophyly of sea eagles (Haliaeetinae), booted eagles (Aquilinae), Aegypinae Old World Vultures, goshawks (Melieraxinae) and harriers (Circinae) was supported; however, none of the kite subfamilies (Milvinae, Perninae and Elaninae), Accipiters (Accipitrinae), harpy eagles (Harpiinae) and snake eagles (Circaetinae) formed monophyletic groups. Specialized limb morphology relating to predation on cavity-nesting species shared by the gymnogene (Polyboroides typus) and the Crane Hawk (Geranospiza caerulescens) is an example of convergent evolution as the two species were not closely related. The nominal genera Buteo, Buteogallus, Accipiter, Circaetus, Hieraaetus, Spizaetus, Aquila, Haliaeetus and Leucopternis were not monophyletic. Investigations at or within the level of species revealed non-monophyly for Hieraaetus fasciatus and H. morphnoides, supporting recognition of H. spilogaster and H. weiskeii as distinct species. Complicated and non-monophyletic relationships among the subspecies of Leucopternis albicollis and L. occidentalis require further investigation to resolve taxonomic nomenclature. Such extensive non-phylogenetic taxonomy at multiple levels emphasizes the need for major taxonomic revision within the Accipitridae. Investigations of genetic diversity and population structure within the harpy eagle (Harpia harpyja) found moderate to high levels of genetic diversity with 417 bases of the mitochondrial control region from 66 harpy eagles. There was no evidence of complete barriers to historical gene flow, however significant genetic differentiation between harpy eagles from Central America and South America was found. Estimates of gene flow were asymmetric with the vast majority of migration in the direction from Central America into South America, suggesting that habitat reduction and fragmentation in Central America may have forced southern migration. Conservation strategies for harpy eagles should aim to maintain gene flow between southern Central America and northern South America.