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Re: The Return of More New Papers
Where comparable, analyses agree on several topological points, including
(1) the basal position of Andesaurus and Malawisaurus and (2) the derived
position of Saltasaurus, Neuquensaurus, Opisthocoelicaudia, and
Not in Curry Rogers' 347-character analysis with plenty of taxa (one of the
sauropod books, 2005).
Each of the three dinosaurian clades - Theropoda, Sauropodomorpha,
Ornithischia - produced a unique track morphotype that appears to be
an independent modification of the chirotherioid pattern attributed to
stern-group archosaurs (thecodontian reptiles).
The type Thulborn attributes to dinosaurs is likely plesiomorphic for
dinosaurs -- and has likely evolved elsewhere, too, such as in *Effigia*.
Ichnological evidence confirms that the theropod hand
also comprises digits 2-3-4.
Except that not one of those hand prints is from a theropod. How do I know?
Because to this day no known theropod has been able to pronate its hands
enough to make non-sprawling quadrupedal walking possible. We are looking at
crurotarsan and/or ornithischian and/or "silesaurid" tracks. In fact, some
of the ichnogenera in question, such as *Atreipus*, have long been
attributed to ornithischians by others.
A few *Coelophysis* specimens are said to have a 5th metacarpal. Is an
illustration published anywhere?
By contrast a frame shift hypothesis, which seeks to reconcile
theropod digits 1-2-3 with avian digits 2-3-4, is less plausible:
Here I agree. I still haven't seen an argument against the idea that the
zone that dies in embryonic bird hands is the prepollex, and at least two
publications that conclude that it is, with several more providing