Behavioural evidence of the systematic relationships of the Patagonian Crested Duck Lophonetta specularioides specularioides

Despite recent advances in phylogenetic analysis, relationships among species of dabbling ducks remain uncertain. In particular, the placement of the Crested Duck Lophonetta specularioides remains in question. Although most researchers have placed the Crested Duck within the tribe Anatini, its placement within the tribe varies from study to study. A study was carried out to determine whether social displays used by the Patagonian Crested Duck Lophonetta specularioides specularioides could inform the phylogenetic debate. Detailed analyses of behavioural displays indicate that although many displays used by the Crested Duck are superficially similar to those of other dabbling ducks (genus Anas) they probably arose via convergent evolution. Such homoplasy provides evidence in support of mitochondrial DNA sequencing studies that place the Crested Duck in a position basal to the rest of the dabbling ducks and suggests that this species lacks close relatives.

A.N.P. Stevens, H.G. Young and F. McKinney, Wildfowl (2005) 55: 119-134