Figure 1.
Age distribution of D. melanogaster protein-coding genes. Divergence times between species are given in millions of years according to Tamura et al. (2004). The bold line indicates the branch leading toward D. melanogaster. Evolutionary time and corresponding branch assignment are shown in italics. For example, branch 6 represents the D. melanogaster–specific branch. Numbers of gene origination events assigned to each branch are underlined (Dmel, D. melanogaster; Dsim, D. simulans; Dsec, D. sechellia; Dyac, D. yakuba; Dere, D. erecta; Dana, D. ananassae; Dper, D. persimilis; Dpse, D. pseudoobscura; Dwil, D. willistoni; Dmoj, D. mojavensis; Dvir, D. virilis; and Dgri, D. grimshawi).
