Figure 1

Unrooted phylogenies used as input in the likelihood-based model tests. (a and b) Phylogeny obtained with CG9631 for the melanogaster (a) and virilis (b) groups. (c) Phylogeny obtained with CG12297 used in the 10 sequence species analysis. Branches in bold in (a) and (c) show the specific lineages analysed in the branch-site model tests. Numbers on branches indicate bootstrap values. Those species for which sequences were obtained in this study are indicated with an *; a in (b) indicates the species for which 10 alleles were sequenced in this study.