This is so simple and so perfectly explanatory that there is no serious doubt about it.In a totally different direction, I've always had the concern that Darwin & Evolution have been elevated beyond the significance they deserve - exactly because it elicits such a defensive response from religious fundamentalism. Sometimes I cringe when I see scientists explaining behavior attributable to "evolution" that I don't see as being any more meaningful as attributing that behavior to an "all powerfull force".
Creationism is a non-starter for myself (as it is for many - if not most with a Catholic background (due in some measure to Tielhard)). But the attributions to evolution seem a bit overcompensating in the other direction. The weakness to evolution is not that it can't disprove creationism, but that it's usefullness in modeling (and thus prediction) are not excatly concise.