Can You Build WALL-E from Repeating Legos?

"A central question in protein evolution is the extent to which naturally occurring proteins sample the space of folded structures accessible to the polypeptide chain." Thus begins a new paper on sequence space for proteins, a concept that has been key to work by leading ID theorists Douglas Axe, Stephen Meyer, and William Dembski. This is the question: Out of the vast space of possible amino acid sequences, how many can fold into functional proteins? ID argues that functional space is such...