Paul Nelson finally writes it.

Both proponents and critics of ID have been waiting a while for this:

Understanding Ontogenetic Depth

"I was supposed to do this a year ago -- well, long before that, too -- but a glacier passed me on the interstate, and then I ran out of gas, got so depressed that I threw my notes into a box, and...oh, never mind. Let's get started....
....The theory of evolution by natural selection does not explain the origin of animal form, because natural selection cannot account for origin de novo of the developmental stages required to construct (i.e., evolve) animals. The concept of OD [ontogenetic depth] helps us to understand why."


I'll be busy reading what he has to say.