"There is still a great deal to learn about the Cambrian, but it
is not a total mystery. For example that is also the time when the
atmosphere became oxygenated. That *might* have something to do with it.
That's an event that will only happen once (we hope!) and therefore
perhaps the life that developed then will only develop that way once.
Even so, 70 million years is a good long time for evolution to take
place. The Cambrian "explosion" is only comparatively rapid."
Susan, I am sorry Susan but you are wrong about oxygen appearing in the
Cambrian. I thought oxygen was thought to have developed in the
atmosphere in the Precambrian so just to be sure I checked Alta vista
and found that oxygen was produced in the middle preCambrian and ozone
layer was thought to be at present levels by late PreCambrian. The
theory is that it was produced by some of the Precambrian plants
(algae).
As someone that teaches paleontology sudden appearances and long stasis
of species are characteristic of the fossil record and conflicted enough
with the old gradualistic model of evolutionary development that a new
paradigm of punctuated equilibrium developed. The Cambrian still
stands out as an unusual burst of sudden appearances. Don't discount
that. The problem from the Christian academician like myself who is
unwilling to see organisms develop by themselves, is how to explain the
limited fossils that exist in the Precambrian or the lack of angiosperms
in the Carboniferous coals I study (are good gymnosperms but not
angiosperms). While I find many faults with the standard neoDarwinian
synthesis - I also find a lot of holes in many Christian attempts at
explaining the fossil record. I do like the flood model folks trying
to use a unique paradigm, but I don't think it works well in explaining
the fossil record.
-- James and Florence Mahaffy 712 722-0381 (Home)227 S. Main St. 712 722-6279 (Office)Sioux Center, IA 51250