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Some thoughts on AVES
YES, Tim!!!! Actually that's an excellent example (are you shocked
that I'm agreeing with you?).
Anchoring Aves on genus Archaeopteryx was an accident of history, and
given how small the gap between archaeopterygids and dromaeosaurs has now
become, I will probably break with that tradition when the time seems right
(most likely when Gregory Paul or George O., or someone else, comes up with
a proposal I really like and with which I can heartily concur).
Another (larger) gap should be chosen to mark the arbitrary line
between Reptilia and Aves, but this time it should be based on osteological
characters that are much more clear-cut (like those which divide therapsids
and mammals). Yes, a character-based taxon---do I hear booing in the
cladist camp? Sorry, but I think that is the best way to ensure relative
stability of content in the long run (it did for mammals before the
cladistic splintering messed it all up).
Where that new line should be drawn is still far from clear, so in the
meantime we should follow the tradition of anchoring it on Archaeopteryx
(which happily coincides with the most commonly accepted cladistic
formulation). But I predict that soon Archaeopteryx will once again be on
the same side of the line as his kissing cousins, but we want to draw the
line at a far more stable place so that it will be a long-lasting change.
And I predict this will happen whether or not BCF is validated in some form
(although I personally hope that it is).
Tim Williams wrote:
I see what you mean. Sort of like putting _Archaeopteryx_ into a separate
"Class Aves", and separating it from its kissing cousins in the
Dromaeosauridae. Indeed, that wouldn't make any sense.
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