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RE: Who says dromaeosaurs can't fly?
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.
"What's the use of the truth if you can't tell a lie sometimes...?
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