hox genes
The linked page is fuzzy, but the analogy is good.
The I.D. textbook authors admit the universality of hox genes but emphasize that hox genes are like "mere" ignition switches.
"Hox genes are like Perili tires. Even though the Focus and Ferrari can sport the same Pirelli tires, does not mean the cars were produced in the same factory-the Focus is not the ancestor of a Ferrari. The Focus and the Ferrari, while similar, are independent entities."
"Hox genes are like the instructors for the head- tail information. "Head goes there." Tail goes there." Some "control" genes are common to many organisms; they are homologous-inherited from our common ancestor."
"Hox genes are like genes with careers in management that don't care what kind of company they're managing." and according to article they like boss around the other genes.
A good discussion in the link.... If you want....
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