Phylogenomic analysis reveals bees and wasps (Hymenoptera) at the base of the radiation of Holometabolous insects

Abstract

Comparative studies require knowledge of the evolutionary relationships between taxa. However, neither morphological nor paleontological data have been able to unequivocally resolve the major groups of holometabolous insects so far. Here, we utilize emerging genome projects to assemble and analyze a data set of 185 nuclear genes, resulting in a fully resolved phylogeny of the major insect model species. Contrary to the most widely accepted phylogenetic hypothesis, bees and wasps (Hymenoptera) are basal to the other major holometabolous orders, beetles (Coleoptera), moths (Lepidoptera), and flies (Diptera). We validate our results by meticulous examination of potential confounding factors. Phylogenomic approaches are thus able to resolve long-standing questions about the phylogeny of insects.

Figure 1.

Holometabolous phylogenetic relationships, showing the monophyly of Coleoptera (beetles), Lepidoptera (moths), and Diptera (flies), to the exclusion of Hymenoptera (bees and wasps). Branch lengths are from maximum likelihood. Numbers report maximum likelihood bootstrap support (in percent); Bayesian posterior probabilities and maximum parsimony bootstrap support are ≥ 99% for each branch (Table 1).