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Origins of Dinosauria (free pdf)

From: Ben Creisler

A new online paper in open access:

Max C. Langer (2014)
The origins of Dinosauria: much ado about nothing.
Palaeontology (advance online publication)
DOI: 10.1111/pala.12108
free pdf:

Research this century has greatly improved our knowledge of the origin
and early radiation of dinosaurs. The unearthing of several new
dinosaurs and close outgroups from Triassic rocks from various parts
of the world, coupled with improved phylogenetic analyses, has set a
basic framework in terms of timing of events and macroevolutionary
patterns. However, important parts of the early dinosauromorph
evolutionary history are still poorly understood, rendering uncertain
the phylogenetic position of silesaurids as either non-dinosaur
Dinosauriformes or ornithischians, as well as that of various early
saurischians, such as Eoraptor lunensis and herrerasaurs, as either
noneusaurischians or members of the sauropodomorph or theropod
lineages. This lack of agreement in part derives from a patchy
distribution of traits among early members of the main dinosauromorph
lineages and requires a more meticulous assessment of characters and
homologies than those recently conducted. Presently, the oldest
uncontroversial dinosaur records come from Late Triassic (Carnian)
rocks of South America, southern Africa and India, hinting at a
south-western Pangaea origin of the group. Besides, macroevolutionary
approaches suggest that the rise of dinosaurs was a more gradual
process than previously understood. Obviously, these tentative
scenarios need to be tested by new fossil finds, which should also
help close the major gaps recognized in the fossil record of Triassic