Quantification of contributions to new gene origination from different mechanisms. (D. mel) D. melanogaster, (D. sch) D. sechellia, (D. sim) D. simulans. These three species together stand for the D. melanogaster species complex. We didn’t identify new genes originating from retroposition or de novo processes in the D. yakuba (D. yak) lineage due to the lack of reliable annotations in this species.