Ecomorphological patterns related to migration: a comparative osteologicalstudy with passerines

An analysis of forelimb and hindlimb skeletal morphology of 15 passerine ge nera was performed to investigate the likely existence of an ecomorphologic al pattern relating morphology to migratory behaviour. Each genus was repre sented by a pair of species, one being sedentary and another migrant. Using a phylogenetic comparative method we found migrant species having longer s ternum, deeper keel and longer coracoids than son-migrant species. Hindlimb morphology was not related to migration. These results are interpreted as adaptations for migrants favouring flight ability, as the larger the sternu m and the coracoids the greater the surface available for attachment of the main muscles involved in active flight.