Re: smallest ANCIENT non-bird dinosaur - was what I was asking

["T. Michael Keesey" <keesey@gmail.com>]

On Thu, May 1, 2008 at 5:37 PM, Tim Williams
<twilliams_alpha@hotmail.com> wrote:
>
>  I do, for one.  Taxa such as _Archaeopteryx_ and _Hesperornis_ and 
> _Ichthyornis_ were put in Aves from the time of their respective discoveries 
> - and by reputable scientists too.  For some reason, Gauthier (1986) limited 
> the name "Aves" to the crown-group.

The reasons are pretty well-argued by Gauthier and de Queiroz (2001).

>  I think in this case we can have our cake and eat it too.  Aves can keep to 
> its traditional usage and be a node-based clade that is defined to include 
> _Archaeopteyx_;

The position of _Archaeopteryx_ (which is a very early taxon) seems
too volatile for this to be very useful. Besides, it's only historical
accident that makes _Archaeopteryx_ so interesting. Really, I question
whether giving this clade any name is useful.

> and Avialae can be retained as a stem-based clade that specifically excludes 
> deinonychosaurs.

It was intended as a name for the clade of volant dinosaurs and
redefined as such (again) by Gauthier and de Queiroz (2001). (The
branch-based definition was an early stab at this.)

>  Mike Keesey wrote:
>
>  >> When people are told that *Eohippus* and even *Propalaeotherium* (the
>  >> Messel horselet) are horses,
>  >> while *Thoatherium* is not one, most of them eat it up.
>  >
>  > Stem-horses, not horses!
>  >
>  >> When people are told that *Ambulocetus* and *Pakicetus* are whales,
>  >> walking whales, most of them accept it as a revealed fact
>  >
>  > Stem-whales, not whales!
>
>  Not to me.  _Pakicetus_ is a whale, and _Eohippus_ is a horse, just as 
> _Archaeopteryx_ is a bird (not a "stem-bird").

These examples would be more like calling _Marasuchus_ a bird instead
of a stem-bird, or calling _Ornithosuchus_ a crocodylian instead of a
stem-crocodylian.

(Incidentally, isn't it kind of funny how zoologists use "horse" and
"whale" in much more inclusive ways than they're commonly used?
Commonly they're limited to one or two closely-related species of
_Equus_ and cetaceans more or less above a certain size threshold,
respectively, not to the entire crown groups, let alone the total
groups.)

>  I've been told that the "coarse" Germanic words were often associated with 
> the actual livestock (e.g., cow/bull/cattle - hence the emphasis on different 
> sexes & ages) and the "refined" French words were often associated with the 
> product (e.g., beef).  This was because the common folk had to rear and take 
> care of the animals; but the right to enjoy the meat was a pleasure reserved 
> for the aristocracy.  I don't know if this factoid is true or not, but it 
> came up in a conversation I had a few weeks ago.

Whether or not it's the exact reason, it's a pretty pervasive pattern:
chicken/poultry, sheep/mutton, deer/venison, swine/pork, calf/veal.
(In all cases, the name of the animal is from Anglo-Saxon and the name
of the meat is from Norman French.)
-- 
T. Michael Keesey
Director of Technology
Exopolis, Inc.
2894 Rowena Avenue Ste. B
Los Angeles, California 90039
http://exopolis.com/
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