“IDers argue that such traits, involving many parts that must cooperate for that trait to function at all, defy Darwinian explanation. Therefore, by default, they must have been designed by a supernatural agent. This is commonly called the "God of the gaps" argument, and it is an argument from ignorance. What it really says is that if we don't understand everything about how natural selection built a train, that lack of understanding itself is evidence for super-natural creation.”