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The fossil record
John Jackson has brought up the argument offered by Fedduccia and others
that cladistic analysis placing _Archaeopteryx_ as a dromeosaur descendant
contradicts the known fossil record, because no Jurassic dromeosaurs are known.
This argument is pretty meaningless; _Archaeopteryx_ had to have been
descended from something, and it hasn't been found. ANY proposed ancestor for
_Archaeopteryx_ is in the same boat as the dromeosaurs; except that we KNOW the
dromeosaurs existed not too long afterwards. Besides, even if you want to
ignore Cretaceous coelurosaurs, the most bird-like things known from the
Jurassic are still theropods.
For a little perspective as to why it would be totally unsurprising to not
find a trace of dromeosaur material in the Jurassic, even if most of the world
was glutted with them, pretend you are paleontologist looking at the Holocene
vertebrate fossil record about 150 m.y. from now, with the preservation as good
as the Late Jurassic is now. The large animal fauna from the Western Interior
of North America is pretty well known, with a scattering of small vertebrates.
A section of Bavaria exhibits pretty spectacular preservation of a lot (but
probably not nearly all) of vertebrates that lived in the general vicinity.
Other then that, the fossil record worldwide is pretty sparse; a few sites here
and there give mostly fragmentary remains that give some idea of some of the
animals that lived around there. It would probably be relatively easy to
conclude that there were no primates (except for humans), elephants, rhinos,
hippos, camels, llamas, large marsupials (assuming th!
ey were detected at all) or monotremes.
By the way, the attitude seems to crop up a lot on this list that being
feisty, arrogant, contentious, and the only subscriber with a brain is going to
give particular credibility to one's argument and just impress the hell out of
everyone. Lets try to stay chill and focus on working out the arguments and
the evidence rather then playing dress-up as Professor Challenger. It
irritates and bores but contributes nothing substantial to the pursuit of
science to try to figure out the way things really happened.
LN Jeff, God's gift to science