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Re: Fw: Most popular/common dinosaur misconceptions
OK. But germane to the thread is the question-- is this the universally
accepted definition of "dinosaur" among paleontologists?
1). I accept that cladistics is useful, and understand the practical need for
simplifying assumptions, but feel that it is not certain (or even likely) that
Iguanodon and Megalosaurus could in reality be traced to a _single_ parent
organism, even if the entire historical record was in hand.
2). The phrase "final common ancestor" seems to me to logically refer to that
magical Original Organism of "life arose at a single point" fame. Of course,
the reality of "single origin" is also quite uncertain. If one accepts that
life could arise on other planets (ooops! undefined and controversial term
alert!), then logically one must accept that it _could_ have arisen more than
once on Earth. There could even have been exchange of genetic information
between lineages. Perhaps I could suggest "most _recent_ common ancestor"?
----- Original Message ----
From: T. Michael Keesey <email@example.com>
Sent: Friday, August 18, 2006 8:12:52 PM
Subject: Re: Fw: Most popular/common dinosaur misconceptions
On 8/18/06, don ohmes <firstname.lastname@example.org> wrote:
> Maybe I am being too harsh. The 22% who were unsure may be folks like me;
> unsure in this post-Linnaean BAD/BAND world just what the hell a dinosaur is.
> And when I was 7 it seemed so clear and well-defined.
What's simpler and more precise than, "the final common ancestor of
_Iguanodon_ and _Megalosaurus_, plus all descendants of that final
T. Michael Keesey
The Dinosauricon: http://dino.lm.com
Parry & Carney: http://parryandcarney.com