Of course, explaining the origin of form is precisely what has made the Cambrian explosion so mysterious. In Chapter 7, in discussing the idea of punctuated equilibrium, I quoted Cambrian paleontologists James Valentine and Douglas Erwin, who concluded exactly that. They argued that neither punctuated equilibrium nor neo-Darwinism has accounted for the origin of new body plans and that, consequently, biology needs a new theory to explain “the evolution of novelty.”5
