The Hox genes are not the big answer many thought:
The role of Hox genes in changing the layout of different body parts during evolution has been challenged by a study led by researchers out of the University of Pittsburgh’s Department of Biological Sciences.
Hox genes are vital to developing differences in repeated body parts such as vertebrae, limbs, or digits in most animal species, including human beings. Ever since their discovery, scientists have thought that modifications to Hox genes could be the primary way that the animal body plan has been altered during evolution.
The paper, “Changes throughout a genetic network masks the contribution of Hox gene evolution,” discusses experiments that pinpoint evolutionary changes in a Hox gene, but found that several other genes had evolved alongside it to generate a difference in pigmentation along the fruit fly body plan. The paper was published in Current Biology June 27. “Body plan evolution not as simple as once believed” at University of Pittsburgh
So Hox isn’t the magic Darwinfix after all. all these genes are coordinating their work, almost like the unrolling of a plan. Maybe exactly like the unrolling of a plan.
Paper. (open access)
See also: genomic: Hoxparadox described (2011)
Follow UD News at Twitter!