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DML weirdness: missing postings (Danish dinosaur tracks, Chinese choristoderes)

From: Ben Creisler

Apologies if this is not a problem after all--but as far as I can
determine, a number of my recent postings have disappeared into cyber
space. The postings on Yanornis, the Asian Dinosaur Symposium, and the
feathered ornithomimid video came through OK. However, the following
items were sent out in different postings to the DML and don't seem to
have gone through. I have removed any special characters to see if
that helps. Again, sorry for the resend for people who received these.
 (Also, sorry about the typo in the subject line for

A new online paper:

Lars B. Clemmensen, Jesper Milan, Gunver K. Pedersen, Anne B.
Johannesen, and Connie Larsen (2014)
Dinosaur tracks in Lower Jurassic coastal plain sediments (Sose Bugt
Member, Ronne Formation) on Bornholm, Denmark.
Lethaia (advance online publication)
DOI: 10.1111/let.12073

Fluvial palaeochannels of coastal plain sediments of the Lower
Jurassic Sose Bugt Member of the Rønne Formation exposed in the
coastal cliffs at Sose Bugt, Bornholm, contain abundant dinosaur or
other large vertebrate tracks in the form of deformation structures
exposed in vertical section. The tracks are represented by
steep-walled, flat-to-concave-bottomed depressions, with a raised
ridge at each side. The tracks are filled with laminated sediments,
draping the contours of the bottom of the depression. Underprints,
stacked concave deformations beneath the prints, are present beneath
each track. Contemporary Upper Triassic-Lower Jurassic strata from
southern Sweden and Poland contain a diverse track fauna, supporting
our interpretation. This is the earliest evidence of dinosaur activity
in Denmark.


Two recent non-dino papers that may be of interest:

Zhang Wei & Gao Ke-Qin (2014)
Early Cretaceous evolution of choristoderes in western Liaoning based
on geographic and stratigraphic evidence.
Journal of Palaeogeography (Chinese Edition) 16 (2): 205-216   (in Chinese)
DOI: 10.7605/gdlxb.2014.02.019
NOTE: pdf can be downloaded for free

The Choristodera,an extinct and specialized clade of
aquatic-semiaquatic diapsid reptiles,had an evolutionary history in
close association with the continental ecosystems of Jurassic through
Miocene on northern hemisphere. During the Early Cretaceous in western
Liaoning Province of China,choristoderes went through a rapid
evolution with diverse ecologic adaptations,as evidenced by their
extensive fossil record from the Yixian and Jiufotang Formations.
Choristoderan fossils have been found from localities within the
Lingyuan,Yixian,Chaoyang and Jianchang areas,with a significant
concentration of Hyphalosaurus localited at the Yixian area. The found
Choristoderan fossils can be divided into five species of four genera
in three families. In terms of geological range,fossils of
Hyphalosaurus and Monjurosuchus are simply restricted to the Yixian
Formation,while those of Ikechosaurus and Philydrosaurus are confined
to the Jiufotang Formation. The extended distribution of the Early
Cretaceous choristoderes in western Liaoning indicates a dispersal
pattern of the group from west to east and from south to north. And
last occurrence of Hyphalosaurus choristoderes in western Liaoning is
recorded with thousands of fossil specimens preserved in tuffaceous
deposits of the Dakangpu beds of the Yixian Formation. Such an unusual
concentration of fossils indicates a possible mass extinction event of
this clade during the Early Cretaceous Aptian Age. All choristoderes
were wiped out from the western Liaoning during the Early Cretaceous
Aptian Age.


Rui Diogo and Julia Molnar (2014)
Comparative Anatomy, Evolution, and Homologies of Tetrapod Hindlimb
Muscles, Comparison with Forelimb Muscles, and Deconstruction of the
Forelimb-Hindlimb Serial Homology Hypothesis.
The Anatomical Record (advance online publication)
DOI: 10.1002/ar.22919

For more than two centuries, the idea that the forelimb and hindlimb
are serially homologous structures has been accepted without serious
question. This study presents the first detailed analysis of the
evolution and homologies of all hindlimb muscles in representatives of
each major tetrapod group and proposes a unifying nomenclature for
these muscles. These data are compared with information obtained
previously about the forelimb muscles of tetrapods and the muscles of
other gnathostomes in order to address one of the most central and
enigmatic questions in evolutionary and comparative anatomy: why are
the pelvic and pectoral appendages of gnathostomes generally so
similar to each other? An integrative analysis of the new myological
data, combined with a review of recent paleontological, developmental,
and genetic works and of older studies, does not support serial
homology between the structures of these appendages. For instance,
many of the strikingly similar forelimb and hindlimb muscles found in
each major extant tetrapod taxon were acquired at different geological
times and/or have different embryonic origins. These similar muscles
are not serial homologues, but the result of evolutionary
parallelism/convergence due to a complex interplay of ontogenetic,
functional, topological, and phylogenetic constraints/factors.