Please Help Me Disprove This (Re: Modern dinosaurs)

You're absolutely right, of course. I mean, hey, how much could we have learned in ten whole years, anyway?Funny thing, though. I'm reading the very article you mention and I don't see where it refutes the cladistic classification of birds as archosaurs anywhere. Could you support your assertion that the article you mention refutes the modern cladistic consensus?Because the article you posted to my reading actually supports the view that birds and dinosaurs evolved from a common ancestor:

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The characteristic pattern of connectivity in the skeletal anlagen in the manus and pes suggests specific morphogenetic mechanisms (20). A molecular genetic understanding of vertebrate limb development has begun to emerge in the last 15 years. Although direct causality between gene expression and morphology is not always clear, stereotyped expression of certain genes accompany the stereotyped pattern of skeletal formation (21). For instance, the expression of the Abdominal B-related genes in the Hox A and D clusters show consistent expression patterns in the autopod of both the fore- and hindlimbs of chickens and mice (22). The consistency of these gene expression patterns between mammals and birds suggests that they are primitive for amniotes and adds molecular evidence for the homology of the ontogenetic pattern.

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At any rate, whatever problems this article appears to pose for therapod ancestry in birds seem to have been addressed, 2 years later, by Wagner and Gauthier in A solution to the problem of the homology of the digits in the avian hand. Care to address either of these articles?Edited by crashfrog, : No reason given.

crash, you're reading it wrong. or maybe right, and misunderstanding something else: birds and dinosaurs did not "evolve from a common ancestor." birds are dinosaurs. the only working scientist that studies anything even relating to this topic who disagrees is one alan feduccia. feduccia utterly rejects the idea that birds evolved from maniraptoran theropods, instead positting that they evolved from tree-lizards with feathers. basically, he's an ornithologist who doesn't know a single thing about paleontology. he writes off the obvious homologies (even claiming that archaeopteryx is not a dinosaur), and basically gets on the nerves of every dinosaur paleontologist everywhere in a way normally reserved for creationists.he's also the co-author of this paper.and as you correctly point out, he's mistaken.

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technically, that's correct. there is one "evolutionist" that disagrees: feduccia. and he's basically a crackpot.since it's off-topic here, feel fre to knock yourself out reading the opinions of some paleontologists regarding his research and the real facts of the cases:Dinosauria On-Line
Dinosauria On-Line for someone who posts off-topic, you are not one to make demands.

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I'm unclear on bird ancestry. Are birds the direct descendants of the last theropods, or the earliest theropods? Or the ancestor of the theropods?I appreciate the correction, though. You're right, birds are dinosaurs, my cladistics text confirms this.

birds are theropods. all birds appear to have basically descended from archaeopteryx lithographica (or rather, the common ancestor of a. lithographica and all other birds is very, very closely related to a. lithographica. "bird" is defined as the group that incorporates both) but it does seem to have been a rather bushy evolutionary path after archie, including the (controversial) idea that many of things we're classifying as "dinosaurs" should be "birds." archaeopteryx is somewhere in the middle. he's a late jurassic theropod.Edited by arachnophilia, : leaving out whole words again

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No you couldn't. You mean, like they all, including Feduccia, agree that birds are archosaurs? Birds are archosaurs.There, that wasn't difficult.