Aerodynamic efficiency of wing morphotypes in the partially migratory Forked-tail Flycacther (Tyrannus savana)

GÓMEZ-BAHAMON V; GÓMEZ JJ; SOTO, IM; JAHN AE; CADENA, D

Manaus

Congreso; Neotropical Ornithological Congress; 2015

Animals that fly require adaptations that allow them toaccomplish locomotion according to their ecological needs. Many migratory birds are able to fly long distances fostered by elongated and pointed wings and lean bodies that allowthem to optimize energy consumption. Tyrannus savana isa partial migrant comprised of three sedentary subspecies distributed in Central America and northern South America, and one austral migratory subspecies that reproduces incentral and southern South America and spends the nonbreeding period in northern South America. A character that differs among the subspecies is the shape of a notch in the outermost primary feathers, which is narrower in the migratory subspecies. In this project we aimed to: 1) determine if this character diffres significantly between subspecies 2) determine if notches are correlated with migratory behavior in a larger phylogenetic context. We determined that 1) theshape of feathers differed by usinf Fourier eliptics and principal component analysis; 2) that there is a potentially higher aerodynamic efficiency in the shape of the migratory subspecies by constructing 3D models and testing themusing fligth simulations and robotic models of the wings and testing them in a wind tunnel and 3) that modifications of the outermost primaries in the family Tirannidae are not correlated with migratory behavior. It has been suggested before that this character is used in sexual selection; thus, in T.savana it could be possible that it is under both natural selection and sexual selection.