_:b665804428 . _:b665804428 . _:b665804428 . _:b665804428 . _:b665804428 . _:b665804428 "Orthology that involves two genes when duplications more recent than the species split have occurred in one species but not the other." . _:b665804428 . _:b665804428 . _:b665804428 .