Bill Payne asked:
[big snip here...]
[...]
>A second question along this same line is whether forms which appear
>to be transitional are truly so. The book _Of Pandas and People_
>shows silhouettes of three skulls: a Tasmanian wolf, a North
>American wolf, and a dog. The cranial-cavity size increases as
>you go from the Tasmanian wolf to the dog, suggesting a
>transitional relationship.
How? That analysis is based on a single parameter which is well
known to vary for multiple, unrelated reasons. Even a comparison
of cranial casts or interior proportions would be far better than
a simple volume measurement.
>However, we know the Tasmanian wolf was a marsupial, while
>the other two are placental mammals. Convergent evolution
>can produce forms which look transitional but which we know
>are not, based upon soft-part anatomy, which of course is
>rarely fossilized.
The Tasmanian wolf and canine skulls are easily distinguishable
and clearly reveal their separate ancestries. No "soft bits"
necessary.
>Is this factor just generally ignored by those inferring
>evolutionary relationships?
Is the possibility of convergence _ignored_ by professionals
in inferring evolutionary relationships? In a word: No.
But let's reconstruct the original question along the lines of
what such a query actually implies:
Are professionals, those who spend most of their laboratory
hours studying the skeletons of animals and the rest
of their time trying to understand relationships
between organisms, such poor scientists that they
completely overlook such a simple, obvious and critical
point in their analyses?
Let's put it this way, what's the probability that the average
8-year-old (or an adult teacher who chooses to use "Pandas and
People" in their classroom) would find something so fundamental
that hundreds of professional evolutionary anatomists would miss.
Thanks for bring that example from "Pandas and People". Never
having seen it, I didn't realize it contained such blatantly
ridiculous and misleading examples. I think Wells' next project
should focus on "Pandas and People" and other such creationist
textbooks that are getting heavy use in our parochial schools.
Kinda like shooting fish in a barrel, I'd guess...
Regards,
Tim Ikeda
tikeda@sprintmail.com
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