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Re: Sci Am - present.



With ref to Jon. Wagner's marbles, (incidentally - a good illustration) and
other mails:

I think the "dromeosaurs after archeopteryx" evidence is useful for BCF but
not conclusive by any means.  

I think the steady convergence 'TOWARDS' birds in other theropods, in the
Cretaceous, is much more convincing, and necessitates, for me, the
birds-to-theropods movement in the Cr.  Once the principle is established
in the Cr, this makes one wonder about earlier, darker ages.  

The Jurassic evidence either way is pretty well zilch.  Pro-BCF evidence
that I know of?  Branched 'feathers' on Sino-type creatures if confirmed 
(acquired presumably at least late J); dare I say it - Protoavis;
"wing-folding" in Herrarosaurus.   It's more down to overall feel at the
moment I think, and imagining scenarios with greater or lesser likelihoods.

Maybe we should be looking really hard for good quality Jurassic sites.
(Alright, alright - "Who'se WE, armchair man!")

Can anyone help with a list of all dinos (inc. pre K-T birds) that DO have
uncinates, and if possible, which theropods we are unsure about?  In
particular can we have a yes/no on Oviraptor, Deinonychus, and
Dromeosaurus.  The latter has 'known' ribs without; the question is,  is it
still possible it had others with?

Possibly the main opposition to BCF arises from the evidence of (for me,
bad) cladistics.  The obvious question now is "How can we tell how reliable
blind cladistics is ?"  Darren Naish tells of an experimant in a field much
richer in fossil evidence than dinosaurs - fish or shells or something. 
There is a longish sequence where every single step, twist and turn of the
way is known - but examples were taken at just a few intervals, to give a
picture about as sparse as we get with dinosaurs.  I don't know the exact
details, but would I have mentioned it if it hadn't been good news for BCF?
 Hopefully DN will fill us in.

John V Jackson    jjackson@interalpha.co.uk

(Wannabeasaurus   beecee-effia - & proud of it!)