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Re: Oh, yeah, the reference...



Roberto Takata wrote:

> First up, a salvo against the BANDits... However, Feduccia &c appear now to
> be arguing that birds and maniraptorans are indeed closely related, but that
> they are NOT theropods or dinosaurs.


When Feduccia et cols intend to strip Maniraptora out of the Theropoda
clade, are they proposing that e.g. _Velociraptor_ is not a theropod?

Apparently, yes. I think Feduccia has hooked into the Czerkas-Martin school of thought, which proposes a diphyletic Theropoda: (1) a Maniraptora-Aves lineage and (2) an everything-else lineage ("true theropods", like coelophysoids, allosaurs, tyrannosaurs, etc) with both lineages evolved separately from an undisclosed ancestral stock. But, these authors are never entirely clear on the dividing line between Maniraptora-Aves and "true" theropods. To which group do ornitholestids_, compsognathids, alvarezsaurids, and ornithomimids belong, for example? The BAND crowd is vague on this issue, as with many other issues.


And, as David says, their articles tend to contradict each other. After arguing for decades that the similarity in bauplan between dromaeosaurs and _Archaeopteryx_ was due to convergence, this crowd now accepts that the similarities are the result of a close relationship - but they now argue that the similarities between dromaeosaurs and non-maniraptoran theropods is due to convergence!

I wou'dn't worry too much about all this. This is the last hurrah! of the BAND movement. It has all the hallmarks of a desperate rearguard action.

Roberto Takata also wrote:

Changing the subject a bit: Therizinosauria and Segnosauria aren't
regarded as synonyms anymore?

AFAIK, neither Therizinosauria and Segnosauria have received phylogenetic defintions, though Therizinosauroidea has. I would say that Therizinosauria and Segnosauria can be regarded as synonyms, given that they are effectively equivalent in content and concept.


Cheers

Tim