Schematic phylogenetic tree representing the insect Orders comprising species where genome sequencing projects have been completed or are in an advanced stage. The figure is a greatly simplified version of a phylogeny shown in  representing the largely agreed relationships between these Orders, plus the major evolutionary transitions for insects (as deduced by synamorphic characters, that is, novel characters derived from preexisting ones) along a time scale expressed in millions of years from present. For each Order with species involved in a genome sequencing project, the node corresponding to its separation from its most closely related order (extant or extinct) is shown (dashed lines represent sister clades).
Sabater-Muñoz et al. Genome Biology 2006 7:R21 doi:10.1186/gb-2006-7-3-r21