On 15-Feb-2005, Scott Weiser wrote:

If it is, care to explain why sharks are still sharks 400 million years
later? It only took 2 million years or so for man to evolve from monkey,
according to evolutionary theory, so why haven't sharks changed appreciably
in 400 million years. If evolution is "the truth," then the world should be
being run by incredibly intelligent sharks, who ought to have evolved far
beyond what they are today. They haven't.

Just because something can evolve, doesn't mean it has to evolve. If it
fits well within its current ecological niche, it can remain in its
current form. Sharks are top predators, they don't have much incentive
to move on.

Mike