'De-evolution' of Drosophila toward a more generic mode of axis patterning.

The genetics of the establishment of the primary axes of the early embryo have been worked out in great detail Drosophila. However, evidence has accumulated that Drosophila employs a mode of patterning that is not shared with most insects. In particular, the use of the morphogenic gradient of the Bicoid homeoprotein appears to be a novel addition to the fly developmental toolkit. To better understand the ancestral mode of patterning that is probably more widely used by insects, several groups have used Evo-Devo approaches as well as sophisticated genetic manipulations of Drosophila to achieve some form of 'de-evolution' of this derived insect. Genetic manipulations of the beetle Tribolium and the wasp Nasonia have validated most of these results.