Are Birds Really Descended from Theropods?

i-draws-dinosaurs:

wikkler:

Me and my colleagues, @i-draws-dinosaurs, @drawingwithdinosaurs, @raptorcivilization, @is-a-velociraptor, and some other guy have actually determined that no, they are not!

They’re actually descended from the bird-hipped dinosaurs, AKA ornithischians. Makes so much more sense… and we’ve even isolated which particular group they came from.

Stegosaurs.

We’ve hypothesized that the shoulder spikes on some stegosaurs slowly developed into wings over the Jurassic. This also explains the sudden disappearance of stegosaurs in the Cretaceous… they evolved into birds!

After this we started looking into the fossil record and discovered that the spikes of Gigantspinosaurus sichuanensis weren’t actually rounded, but flat! Perfect for a wing. With this new data we were, in fact, able to recover birds as being nested within Stegosauria, with Gigantspinosaurus being the sister group to traditional Avialae (note, however, that Archaeopteryx, Anchiornis, and Balaur stayed in Deinonychosauria in our analysis, which correlates with the stegosaurs-to-birds theory, and Sapeornis turned out to be an oviraptorosaur).

Some nomenclature, however, is probably going to need changing. Under the current definitons of clades, Avialae becomes synonymous with Ornithischia. We might need to add Gigantspinosaurus sichuanensis as an external specifier…

Here’s a reconstruction, courtesy of @i-draws-dinosaurs, of the “new” Gigantspinosaurus.

We shall soon publish a blog about our findings, plus more research into parts of the dinosaur tree with our new blog, Stegosaur Heresies! Coming soon.

You’ve heard of BANDits (Birds Are Not Dinosaurs) 

You’ve heard of SAND (Sauropods Are Not Dinosaurs) 

Now prepare for … BATS (Birds Are Totally Stegosaurs)