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Sauropod paleohistology papers



Ben Creisler
bcreisler@gmail.com

The new August issue of  the Biological Journal of the Linnean Society
is devoted to paleohistology:

Biological Journal of the Linnean Society 112(4):
http://onlinelibrary.wiley.com/doi/10.1111/bij.2014.112.issue-4/issuetoc

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Two dinosaur papers may be of special interest:


Jessica Mitchell and P. Martin Sander (2014)
The three-front model: a developmental explanation of long bone
diaphyseal histology of Sauropoda.
Biological Journal of the Linnean Society 112(4): 765–781
DOI: 10.1111/bij.12324
http://onlinelibrary.wiley.com/doi/10.1111/bij.12324/abstract

The bone histology of non-avian dinosaurs is enlightening for
understanding many aspects of the growth and development of these
long-extinct animals. The rate of bone apposition and remodelling in
the shaft of long bones appears to be accelerated in some groups and
decelerated in others. We propose a developmental model to illustrate
these fundamental aspects of long bone diaphyseal histology at
different growth stages. We developed the model based on an
ontogenetic series of long bones of the sauropod dinosaur Apatosaurus.
The model describes the histology and microanatomy based on three
fronts that move radially: the apposition front, the Haversian
substitution front, and the resorption front. When applied to
additional sauropod dinosaurs, differences and similarities observed
in the microstructure of the different taxa could be explained with
the model. The benefit of this model is that it is not limited to
Sauropoda but appears to be applicable to a broad range of terrestrial
amniote long bones and thus could provide unique insights into life
history and evolutionary patterns of bone development.

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Maitena Dumont, Andras Borbely, Anke Kaysser-Pyzalla and P. Martin Sander (2014)
Long bone cortices in a growth series of Apatosaurus sp. (Dinosauria:
Diplodocidae): geometry, body mass, and crystallite orientation of
giant animals.
Biological Journal of the Linnean Society 112(4): 782–798
DOI: 10.1111/bij.12335
http://onlinelibrary.wiley.com/doi/10.1111/bij.12335/abstract


Comparative studies of body mass, cortical bone geometry, and
preferred crystallographic orientation (texture) of bone mineral in an
ontogenetic series of the sauropod, Apatosaurus sp., and recent
animals are reported. The cortical bone geometry shows that sauropods
have an expansion of the cortical thickness as a result of their
heavier mass. It is shown that a universal power-law relationship
connects body mass to bone length, suggesting the validity of Wolff's
law for sauropods. Moreover, sauropod and mammalian bones seem to be
exposed to the same compressive bone stress. X-ray texture
measurements of long bones were used to study the orientation of
carbonated hydroxyapatite (HA) crystals. All bones investigated showed
a 001-fibre texture, in which the c-axis of the HA crystals is
oriented along the bone axis. Texture strength (defined by the
alignment of HA crystals) appears to be of only minor importance
regarding the mechanical strength and seems to be influenced by the
loading mode of the bone.