Re: New alvarezsaurid

["T. Mike Keesey" <tkeese1@gl.umbc.edu>]

On Sun, 22 Mar 1998, Jaime Headden wrote:

> <<Oh well, it looks like another nail in BCF's coffin.>>
> 
> <I don't see how that's so... BCF says that the lineage from basal
> dinosaurs to modern birds were small, arboreal/scansorial creatures that 
> spit off larger terrestrial lineages, right? Alvarezsaurids would just 
> be another one of these lineages.>
> 
> And why they could _not_ be the antecendants I don't know,

Since when are alvarezsaurids, a highly derived group of Late Cretaceous
animals, considered as possible bird ancestors?

> but *Shuvuuia* seems to be the first to have a prokinetic snout,

Isn't it from the Late Cretaceous? In fact, the web article I saw
mentioned 70 million years ago, which would be Maastrichtian. Plenty of
modern-type birds around by that point.

> and while 
> this may be novel and still the first appearance of this character that 
> led on to other lineages (Euaves, for example)

I am unfamiliar with the term Euaves -- is it a synonym of Neornithes?

> it still asserts  theropods were the ancestors of birds.

BCF doesn't disagree with this, really -- although the way it's worded
might make one think so.

> But like I said on the other *Shuvuuia* post I sent today, I'll not 
> state yea or nay to BCF---or BADD, etc..

I agree, although I think a definite nay can be given to BANDD ("Birds Are
Not Dinosaurs, Dammit!").

--T. Mike Keesey
tkeese1@gl.umbc.edu
DINOSAUR WEB PAGES -- http://www.gl.umbc.edu/~tkeese1/dinosaur/index.htm