The comment that in the YEC view, the fossil record shows that critters
have stayed the same is at best true for only a few species, but
misrepresents the broad picture. There are those cases of forms that
seem to have stayed basically unchanged for vast time periods. But I
believe that they would be the exceptions.
Our own AWOL Glenn posted some info to the point that there are NO
representatives of the 4631 living mammal species found as fossils beyond
Miocene (>23 MY), not a single one ! Worse than that, the span of any
one of the 7784 extinct species is usually only one epoch. The turn-over
Similar histories with different time horizons could probably be made for
birds, flowers, and hominids and many other "kinds".
The weight of this argument hinges on the acceptance of some validity to
dating methods. Most YECs through out the very idea of radio dating, but
then implicitly use the frame of mind that layers=time to say that the
fossils really are sequential pictures of past time. Isn't that having
it both ways ?