Flight feather structure evolves to match habitat and flight requirements. This was concluded in a phylogenetic comparative study in which we used 4 flight feather structure parameters of 137 European bird species. We found that flight style (4 categories: flap-soaring, flap-gliding, continuous flapping and passerine type) and habitat (3 categories: terrestrial, riparian and aquatic) are highly significant predictors of primary feather structure. For instance, soaring and gliding birds have primary feather vanes with lower barb density than those that flap their wing at higher frequencies (i.e. continuous flappers and passerines). Moreover, the outer (distal) primaries of species having higher wing-beat frequencies was more wider relative to the innermost (proximal) primary than in less intensely flapping species, which had outer primary rachis width closer to that of the innermost primary. Regarding the effect of habitat type, we showed that aquatic species bear primary feathers with higher barb and barbule density, and within this habitat group diver species have even more densely ramified feathers than aquatic non-divers.

The manuscript was submitted to Functional Ecology where the editor-in-chief requested major revision based on the comments of referees. We are now working to improve this work by considering the highly constructive criticism raised by reviewers.

Our results were also disseminated at the conference entitled “Modern Phylogenetic Comparative Methods and their Application in Evolutionary Biology” held in Seville, Spain, 11-15 November 2014. Our results were presented by Orsolya Vincze, who won the runner-up prize for the best student talk. Congrats!

Authors marked with boldface are EvolEcol members, while asterisks indicate student authors.

Pap PL, Osváth G, Sándor K*, Vincze O*, Bărbos L*, Marton A*, Nudds RL and Vágási CI. Interspecific variation in the structural properties of flight feathers in birds indicates adaptation to flight requirements and habitat.