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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.

Brian

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

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