Scatterplots from unbiased PCAs using 125 spectra from flies of 13 different species. Species-specific color-coding corresponds to that shown in Fig. 2. Spectra belonging to one species are outlined by a convex shape or an ellipse. A: PCA containing all spectra, with 95% concentration ellipses for three subgenera/species groups. B: PCA using only spectra from D. pseudoobscura and D. miranda, with 50% concentration ellipses. C: PCA performed with spectra from the subgenus Drosophila but without D. pseudoobscura and D. miranda, with 95% concentration ellipses. D: PCA of the spectra from the subgenus Sophophora, with 95% concentration ellipses.
Feltens et al. BMC Evolutionary Biology 2010 10:95 doi:10.1186/1471-2148-10-95