Fig. 4

Many genes involved in a given process are detected only in one of the two species. We combined all genes found in the fly to be involved in our processes (column 1) and/or those genes that we identified in the iBeetle screen to be required in the same process (column 3) to assemble a set of genes comprising all genes currently known to be required in any insect for the processes analyzed here (column 4). Of the fly gene set (column 1) about two thirds had been tested in the iBeetle screen. Of those, three quarters showed a similar function in our beetle while one quarter appeared to be fly specific (column 2). The subdivisions of columns 1 and 2 are based on Figs. 2 and 3 and Additional file 2: Fig. S1. From the numbers in columns 1-3 we calculated the portions of genes of the combined insect gene set (column 4), which were detected only in Drosophila (11%), only in Tribolium (37%), or in both (52%). See text for details and discussion of potential systematic biases. B) Respective values for the single processes show that the Tribolium screening platform revealed 20–50% novel genes relevant for a process (i.e., which were not detected in Drosophila). See Additional file 5: Table S4 for calculations. Given these results neither model system can be used alone as a proxy for insects or protostomes in general and that Tribolium is a very useful complementary screening platform