To : Arthur Biele Subj: Transitions AB [Originally, Archeopteryx] was considered a reptile

From: John Thompson                                    Posted: 24 Sep 94  11:30
To  : Arthur Biele
Subj: Transitions

AB> [Originally, Archeopteryx] was considered a reptile with bird
AB> like features. Today, 'Archi' is known to be a 'true' bird.

Archeopteryx is considered to be a "true bird" only because
taxonomists have agreed upon using feathers as the defining
characteristic for Class Aves.  This does not change by a whit the
fact that Archaeopteryx has many reptilian features (eg pubic
peduncle, bony tail, toothed jaw, etc.) not seen in *ANY* modern
bird; this is the reason it is considered to be transitional
between birds and reptiles.

AB> All it's features were complete and fully functional.

What's the point of this claim? Only creationists expect to find
incomplete structures in transitional forms.  Just another
manifestation of teleological thinking, I guess.

AB> experts agree that Archeopteryx is an evolutionary dead end,
AB> and not the ancestor of any modern birds (which are to be
AB> found as far back as the early cretaceous period).

First, how does being an evolutionary "dead-end" negate
transitional form status?  This looks like typical creationist
"scala natura" thinking.

Second, if you're thinking of Protoavis as your modern bird
"found as far back as the early cretaceous period" you ought to be
aware that 1) Protoavis has not been closely investigated by
anyone other than its discoverer, so little can be said about it's
taxonomic staus; and 2) due to the poor state of preservation of
the find, his assertion that Protoavis has feathers (and therefore
its status as *ANY* type of bird) is not widely accepted, much
less any claims of it being a "modern bird."

 * KingQWK 1.05 # 39 * Evolution: the unifying principle of Biology!

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