Figure 1.

Phylogeny of insects species used in this study. This consensus tree and the divergence times (million years) are based on the following references: Drosophilidae [16,66], Diptera [65], Lepidoptera [67,68], Tenebrionidae [17], Blattaria [18,19,69] and insects [70-72]. Dots indicate the species used for detection of selection in usp along different branches. Black dots: Drosophilidae; blue dots: Diptera (branch C); green dots: divergence between Antliophora and Amphiesmenoptera (branch B); red dots: emergence of Mecopterida (branch A); white dots: Lepidoptera; grey dots: Tenebrionidae; yellow dots: Blattaria.