Resumen de Age- and sex-related differences in the wing shape of Bluethroats (Luscinia svecica) in south-east Spain
Two main treatments of the analysis of wing shape obtained from primary lengths and primary distances were used by means of principal components analysis (PCA) in order to assess age and sex differences in a sample of wintering Bluethroats in SE Spain. A sizeindependent technique, developed by Chandler & Mulvihill (1 988, Ornis Scand. 19: 2 12-2 16), which does not control for body size and allornetry, was used on the original variables. A statistical modification that controls for allometric effects and body shape (Senar et al. 1994, J. Avian Biol. 25: 50-54) was subsecuently used on the standarized primaries. Wing shape of Bluethroats could be summarized by three Principal Components (PCA) which explained 80% of the total variation. The two techniques differed in their ability to detect age- or sex-related differences in the wing shape of Bluethroats.
