On Fri, 20 Apr 2001 10:27:29 -0400 James_Taggart@Multilink.com writes:
> One issue that occurs to me about transitional fossils is that they are
> just that, not long lived species. Almost by definition
> transitional fossils will be rare (or even absent) in the record,
because
> there never will have been many of them. The
> liklihood of any particular creature being fossilized is small enough,
the
> liklihood that the one that gets fossilized is the
> actual ancestor of all following creatures is practically zero. So we
> shouldn't be surprised that the transitions are hard
> to follow. The amazing thing is that we can follow it at all.
This looks a little like circular reasoning. Transitional fossils are
short-lived, short-lived fossils are rare, rare fossils are transitional.
And in order for transitionals to be rare/short-lived, the environment
must have been in a rapid state of linear change (not back and forth) to
drive natural selection through the transitional stage - just rapid
enough to keep the transitional stage short, but just slow enough to
allow evolution rather than extinction. And then the transitional stage
ended when the environmental changes stopped. And then there was a long
stable period when no evolution occurred, just lots of fossils. And then
there was another linear change in the environment - not too fast but not
too slow, and then.....
This is beginning to sound more like a just-so story than a scientific
theory.
Bill
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