Archaeopteryx
Ken Kinman
kinman at HOTMAIL.COM
Sun Feb 6 11:23:22 CST 2000
With the recent discovery of feathered dinosaurs, I think if
Archaeopteryx had just been discovered yesterday, it might be classified as
a feathered dinosaur by some and a bird by others. It would probably be
hotly debated.
However, Archaeopteryx has such a long history of being classified as
the first bird, and adopted as a cladistic "anchor" as the first "primitive"
clade of birds, that I continue to classify Order Archaeopterygifomes as the
most primitve bird order (sister group to all other bird orders).
Using that admittedly arbitrary cut between reptiles and birds (but
almost universally still agreed upon), one can then argue which side of this
line we should place controversial groups. For instance, in 1994 I placed
Order Mononykiformes as the second most primitive clade of birds (following
paleontologists at the American Museum). But Sereno believes mononyiforms
(and alvarezsaurids) are more primitive and belong in the dinosaur order
Saurischiformes (among other dinosaurs that evolved some bird-like
characters in parallel with the "true birds").
So to answer Curtis' question, Archaeopteryx is almost universally
regarded as a primitive bird. But all birds are reptile descendants, and
there is a Kinman marker in my reptile classification explicitly showing
birds evolved from Saurischiformes. But if by chance, Alan Feduccia and
Larry Martin happen to be correct (i.e., birds are not direct descendants of
dinosaurs), I would simply move the marker (for birds), perhaps as sister
group to all dinosaurs, or more deeply near some undiscovered "thecodont"
group that Fedducia apparently envisages (but personally I believe this is
wishful thinking on the part of those who oppose regarding birds as dinosaur
descendants---time will tell).
----------Ken Kinman
P.S. Vermes is one of the most polyphyletic wastebaskets in the history of
systematics. It has nothing to do with which "paraphyletic" groups are
useful and which ones are not. Everyone agrees that polyphyletic groups are
unnatural.
******************************************************
>From: Curtis Clark <jcclark at CSUPOMONA.EDU>
>Reply-To: Curtis Clark <jcclark at CSUPOMONA.EDU>
>To: TAXACOM at USOBI.ORG
>Subject: Re: Farewell to Species - reticulation
>Date: Sat, 5 Feb 2000 12:15:04 -0800
>
>At 05:43 PM 00.02.05 +0100, Hubert Turner wrote:
> >Everybody nows what a reptile or a dicot looks like!
>
>I agree that it is a mistake to force nomenclature to strictly follow
>phylogeny, but I wonder, is Archaeopteryx a bird or a reptile? Is
>Archaeopteris a pteridophyte or a spermatophyte? For that matter, is
>Amborella a monocot or a dicot? Just because we "recognize" a grouping,
>that doesn't necessarily make it useful. There used to be a phylum
>Vermes--everyone can recognize a worm. Where is it now?
>
>----------------------------------------------------------------
>Curtis Clark http://www.csupomona.edu/~jcclark/
>Biological Sciences Department Voice: (909) 869-4062
>California State Polytechnic University FAX: (909) 869-4078
>Pomona CA 91768-4032 USA jcclark at csupomona.edu
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