Accurately distinguishing between which taxa are dinosaurs and which are birds is a necessary first step in showing that birds and dinosaurs are not connected.
Dinosaurs*:
Tyrannosaurs, Compsognathus, Ornitholestes, Therizinosaur
Birds:
Paraves (flying and flightless), Alvarezsaurids (secondarily flightless), Oviraptors (secondarily flightless)
I will deal later with the traits that help us determine how to distinguish between dinosaurs and birds.
Of course the primary trait is pennaceous feathers. Another significant trait is the orientation of the pubic bones.
Here are some of the traits that distinguish dinosaurs* from birds:
Pennaceous feathers, pubic bone orientation, sternum, patagium and propatagium.
Those are a few of the traits. These traits listed are very significant.
* by "dinosaurs" I am referring to saurischian dinosaurs since the dino to bird theory claims that birds descended from saurischian dinosaurs
http://en.wikipedia.org/wiki/Maniraptora
ReplyDelete"Maniraptora is the only dinosaur group known to have included flying members, though how far back in this lineage flight extends is controversial. Powered and/or gliding flight is believed to have been present in some types of dromaeosaurid, such as Rahonavis and Microraptor.[5] Other groups, like the Oviraptorosauria, are not known to have been capable of flight, but some scientists have suggested that they could be descended from ancestors which flew. Gregory S. Paul has suggested that this might be the case. Paul has gone as far as to propose that Therizinosauria, Alvarezsauroidea, and the non-maniraptoran group Ornithomimosauria descended from flying ancestors as well.[6]"
I am suggesting that Oviraptorosauria, Alvarezsauroidea and Ornithomimosauria were secondarily flightless birds
At the moment I consider Therizinosauria to be dinosaurs
From Pillbox Pete:
ReplyDeleteWhy aren't you publishing my comments?
My response:
You will have to submit some first.