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Re: New paper on pre-Archaeopteryx coelurosaurian dinosaurs



And another thing...

"So if evolution is true, how come we still have monkeys?" (That imbecile running for office out east who is not a witch.) ----- Original Message ----- From: <bh480@scn.org>
To: <dinosaur@usc.edu>
Sent: Tuesday, October 26, 2010 5:35 AM
Subject: New paper on pre-Archaeopteryx coelurosaurian dinosaurs


From: Ben Creisler
bh480@scn.org

In case this new paper has not been mentioned:

Xing Xu, QingYu Ma and DongYu Hu (2010)
Pre-Archaeopteryx coelurosaurian dinosaurs and their
implications for understanding avian origins.
Chinese Science Bulletin (advance online publication)
DOI: 10.1007/s11434-010-4150-z

The last two decades have witnessed great advances in
reconstructing the transition from non-avian theropods to
avians, but views in opposition to the theropod
hypothesis still exist. Here we highlight one issue that
is often considered to raise problems for the theropod
hypothesis of avian origins, i.e. the "temporal paradox"
in the stratigraphic distribution of theropod fossils -
the idea that the earliest known avian is from the Late
Jurassic but most other coelurosaurian groups are poorly
known in the Jurassic, implying that avians arose before
their supposed ancestors. However, a number of Jurassic
non-avian coelurosaurian theropods have recently been
discovered, thus documenting the presence of most of the
major coelurosaurian groups in the Jurassic alongside, or
prior to, avians. These discoveries have greatly improved
the congruence between stratigraphy and phylogeny for
derived theropods and, effectively, they reject
the "temporal paradox" concept. Most importantly, these
discoveries provide significant new information that
supports the relatively basal positions of the
Tyrannosauroidea and Alvarezsauroidea among the
Coelurosauria. Indeed, they imply a new phylogenetic
hypothesis for the interrelationships of Paraves, in
which Archaeopteryx, the Dromaeosauridae, and the
Troodontidae form a monophyletic group while the
Scansoriopterygidae, other basal birds, and probably also
the Oviraptorosauria, form another clade. Mapping some of
the salient features onto a temporally-calibrated
theropod phylogeny indicates that characteristics related
to flight and arboreality evolved at the base of the
Paraves, earlier than the Late Jurassic.


http://www.springerlink.com/content/387524025j71h741/


Also now available for free at:
http://digitallibrary.amnh.org/dspace/handle/2246/6087

Daniel T. Ksepka and Mark A. Norell, 2010.
The Illusory Evidence for Asian Brachiosauridae: New
Material of Erketu ellisoni and a Phylogenetic
Reappraisal of Basal Titanosauriformes
American Museum Novitates 3700: 1-27