Jerry Coyne, coauthor of Speciation, has a mildly negative review of Sean Carroll’s Endless Forms Most Beautiful
(my short take here) up at Nature. Coyne states that, “…but its faintly self-congratulatory message – that the most important problems in understanding the evolution of development have been solved – left me feeling uncomfortable.” He goes on to offer:
…But the underlying statistics are deceptive; even a 1% difference in DNA sequence implies a substantial difference in protein sequence. We now know that humans and chimps have different amino-acid sequences in at least 55% of their proteins, a figure that rises to 95% for humans and mice. Thus we can’t exclude protein-sequence evolution as an important reason why we lack whiskers and tails.
If you read this weblog you know that glib generalizations based on a commonly used figure in the literature can be deceptive. I personally believe, from my reading of Carroll’s book, that Coyne has taken his message the wrong way. Carroll seems to be arguing that gene regulation (that is, variable expression) has been the most important neglected factor in understanding the evolution of development. Certainly new technology for assaying gene expression has blown the lid off of many of the limitations on collecting enough data. Additionally, any biologist who writes for a lay audience seems to get a bit carried away and want to package their message as the One Great Truth. Both Coyne and Carroll are certainly correct to some extent, and I doubt that the viewpoint of either one will carry the day in the end. I suspect that the importance of gene duplication, alternative regulation, and direct nonsynonymous changes to the DNA sequence will be measured by the factor which looms largest in the uniqueness of humanity, that is, what separates us from the chimpanzees.1
Evolgen has more.
1 – Regional Patterns of Gene Expression in Human and Chimpanzee Brains, Genome Res. 2004 Aug;14(8):1462-73.
Posted by razib at 12:50 PM