Wallace Arthur, head of the zoology department at the University of Ireland and evolutionary biology researcher, reviews in Nature (Vol 447|17 May 2007) the book From Embryology to Evo-Devo: A History of Developmental Evolution. There were some breaths of fresh air in the review [my emphasis]:
Third, and most important in my view, the origin of novelty is becoming one of the major themes of evo-devo. Attention is shifting from the retention of the old (as in recapitulation) to the creation of the new (be it an eye, a leg, a feather or even a whole body plan). Both the historical and the current importance of novelty emerge repeatedly in the book.
How do novelties arise? We can’t yet agree on a definition for them, let alone answer this fundamental question. But we can see the nature of the challenge ahead. Wagner points out that there is a growing connection between microevolutionary (intraspecific) evo-devo and quantitative genetics (where intraspecific variation is analysed in terms of quantitative trait loci). This connection is a positive thing, although it is perhaps limited in scope because it may not solve what many perceive as the raison d’être of evo-devo. As Wagner says: “One of the main sources of intellectual excitement in devo-evo (sic) is the prospect of understanding major evolutionary transformations.†Whether these end up being unique events or long-term accumulations of the mundane remains to be seen, but either answer will be exciting in its own way.
The first thing of note is a candid admission that there is no plausible explanation right now for the origin of novelty. Evo-devo hopes to shed light on the mystery of macroevolution. The second thing of note is that the term “microevolutionary” is used. We often hear from clerics in the Church of Saint Charles Darwin that real evolutionary scientists don’t use the terms microevolution and macroevolution. Ostensibly because they all have the strong belief that the two describe the same process and separating it into two regimes is something that only knuckle dragging creationists employ to obfuscate a theory that’s as well tested as gravity. So here we have a real evolutionary biologist using exactly the language ID proponents use and asking exactly the question we ask – “What is the origin of macroevolutionary novelty?” How refreshing.