RE: Who says dromaeosaurs can't fly?

["Brian Lauret" <zthemanvirus@hotmail.com>]

I think we're getting a bit off subject by now.But I do want to give my view 
on the entire issue.
I personally think the earliest evolution of birds may be unresolvable by 
cladistic methods because I view the earliest bird (this is very debatable 
of course,it's totally conjectural from my side) as the earliest arboreal 
dinosaur with at the ability to fly.This may have been what we call a "basal 
coelurosaur." (though the allosauroid mentioned may mean it was more of a 
basal tetanurine)of course it didn't have the nessecary equipment for long 
distance flight and could probably only fly small distances allowed only by 
small size,light weight and the assistance of some sort of wings,that may at 
first have evolved for social use (as a display,or so).But of course,this 
opened perspectives and with the descendants of this creature came about a 
evolutionary explosion.By improving flight capabilities these birds were 
better able to compete with both each other and small pterosaurs.And what we 
see is massive convergence and mosaïc evolution. With birds that have clawed 
wings but toothless beaks (confusciusornithids),birds with tails that 
converge on those of basal pterosaurs (like dromaeosaurs) and many more.This 
would already be barely resolvable but to make things worse quite a number 
of mostly the earliest,most "unbird-like" birds became secondarily 
flightless,reversed many flight-related features and evolved in a different 
way.We can be pretty confident 
dromaeosaurs,troodonts,alvarezsaurs,oviraptorosaurs,therezinosaurs as well 
as patagopterygids belonged in this category.But I think 
tyrannosauroids,ornithomimoids and at least some "basal coelurosaurs" might 
belong here too.Just because these might have descended from some of the 
most primitive birds.I do not view neornithines as the most recently evolved 
of birds ,they were just the lucky survivors of mass extinctions at the end 
of the Cretaceous unlike their differently evolved relatives.

At least that's how I view all of this....please comment me if you think 
I've missed something or am wrong.

Brian

"What's the use of the truth if you can't tell a lie sometimes...?
(Kokane,True Lies,2000)

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