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MISSING TIME



Again on this list, there are shouts that the mere thirty-million year gap
between _Deinonychus_ and _Archaeopteryx_ is indicative of archaeopterygid
ancestory of dromaeosaurs, rather than something like the reverse.  This is
clearly absurd.  Aside from the Bathonian dromaeosaur teeth from the UK, the
time gap is really not that big.

Take for example, the very basal ornithopod _Bugenasaura infernalis_.  This
animal is one of the most 'primitive' ornithopods known, yet appears in the
Maastrichtian of North America.  The single partial skull has a long and
robust palpabral and 5 premaxillary teeth that run the whole length of the
premaxilla, rather than being confined to the caudal 2/3 of the premaxilla as
in all other ornithopods but _Agilisaurus_.  _Bugenasaura_ seems to form an
unresolved trichotemy with _Agilisaurus_ and all other ornithopods.
_Agilisaurus_ and the earliest forms of "all other ornithoopods" appear in the
Dashanpu formation, approximately 160 MA.  There is a nearly 90 million year
gap for ancestors of _Bugenasaura_, but that indicates only one thing: that
the fossil record isn't as complete as we'd like it to be.  I don't think that
anyone supposes that _Bugenasaura_ is some sort of strange derived hadrosaur
or something like that.

Which brings us back to another point.  _Archaeopteryx_ is clearly more
closely related to modern birds than either are to dromaeosaurs.  I have
posted on this numerous times before.  Check out the archives.

Peter Buchholz
Tetanurae@aol.com

No, Tommy, it's good, you can fry it up with eggs.