Re: Similarity of invertebrates

Glenn Morton (GRMorton@gnn.com)
Wed, 13 Mar 1996 15:58:45

Hi James.

It has been a while since we have corresponded. You wrote:

>
>Glen wrote:> sciences. I am a geophysicist. I agree with George that
>> geology brings
>> probably the greatest challenge to one wanting to reconcile science with
>> scripture. The biggest problem is that almost of the living animals
>> prior to
>> the Eocene (about 55 million) years ago are different from any animal
>> alive
>> today. I am working on a mammalian database with the geologic range of
>> the
>> living and fossil mammalian species. To date, I have been unable to find
>> a
>> single species alive today which was found fossilized prior to the
>> Oligocene
>> (about 35 million years ago.) I have only found one or two of these
>>cases.
>> Most species are not found in rocks older than the Pleistocene (2
> million
>> years ago).
>>
>
>I really shouldn't take the time since I have two test to finish, but
>like Glen I also work professionally with fossils and I thought his post
>might lead folks who do not work with fossils into thinking that fossils
>are generally rather different than modern taxa. The story is a bit
>different for different groups, but in both invertebrates and in the
>plant record many of the groups appear rather suddenly in the fossil
>record and many of them are quite similar to modern repreentatives. I
>am not suggesting that the same species are there, but I am suggesting
>that many groups have a very long fossil record and do not show a lot of
>change over their range.

As far as mammals are concerned, you don't have to go back very far to find
out that the species are 90% different. I have collected the data for genera
and here is what the numbers look like.

Modern Genera
Paleocene Eocene Oligocene Miocene Pliocene Pleistocene Recent
(65-55) (55-37) (37-23) (23-6) (6-1.8) 1.8-.001) (.001-0) Myr
0 3 11 57 133 417 1135

Extinct Genera
213 566 483 691 626 409 5

One can see from this that IF, and the young earth creationists believe, all
the animals in the fossil record are the remains of animals that died in the
flood, there is a problem. The animals which we find alive today are not
found in pre-flood strata!

One reason I am concentrating on mammals, is that if the widely accepted view
of the flood is true, then all the mammals HAD to be on the ark. This may
not be the case for many of the invertebrates. Thus I feel that the case of
the mammals is more critical to the widely accepted apologetic.

Now concerning the invertebrates of which you speak. At least some present
us with a huge problem in the fossil record. Moore, Lalicker and Fischer
note,

"Among Brachiopods, the condition known as homeomorphy is common.
This consists of such striking external resemblance between
shells belonging to different genera that, without careful study,
one may be mistaken very readily for the other. Not only do we
find shells belonging to different groups which have similar
shapes, but their patterns of ornamentation may be nearly
identical. Examination of the internal structure may show that
these differ radically, or the shell substance of one is
impunctate, whereas the other is perforated by numerous minute
puncta."~Raymond C. Moore, Cecil G. Lalicker, and Alfred G.
Fischer, Invertebrate Fossils, (New York: McGraw-Hill Book co.,
1952), p. 217.

Some of these features may not show in the fossil record and this makes it
hard to distinguish different species in the fossil records of some groups of
invertebrates. In this I would agree with your objection.

I would also say that every case of a "living fossil" I have seen claimed, I
have found major differences between the living form and the fossil forms,
with the exception of lingula. Of course, it is a brachyopod. A case in point
is the horseshoe crab which is often cited in the apologetical literature as
a living fossil. The Permian varieties of these animals is markedly
different from the living example. Look up Xiphosura in Moore, Lalicker and
Fischer.

glenn