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RE: Baby mammoths get CT scans (free pdf of paper)



Ben Creisler
bcreisler@gmail.com

The paper is now online and in open access:



Daniel C. Fisher, Ethan A. Shirley, Christopher D. Whalen, Zachary T.
Calamari, Adam N. Rountrey, Alexei N. Tikhonov, Bernard Buigues,
Frédéric Lacombat, Semyon Grigoriev, and Piotr A. Lazarev (2014)
X-ray computed tomography of two mammoth calf mummies.
Journal of Paleontology 88(4):664-675
DOI: 10.1666/13-092
http://www.bioone.org/doi/abs/10.1666/13-092

Two female woolly mammoth neonates from permafrost in the Siberian
Arctic are the most complete mammoth specimens known. Lyuba, found on
the Yamal Peninsula, and Khroma, from northernmost Yakutia, died at
ages of approximately one and two months, respectively. Both specimens
were CT-scanned, yielding detailed information on the stage of
development of their dentition and skeleton and insight into
conditions associated with death. Both mammoths died after aspirating
mud. Khroma's body was frozen soon after death, leaving her tissues in
excellent condition, whereas Lyuba's body underwent postmortem changes
that resulted in authigenic formation of nodules of the mineral
vivianite associated with her cranium and within diaphyses of long
bones. CT data provide the only comprehensive approach to mapping
vivianite distribution. Three-dimensional modeling and measurement of
segmented long bones permits comparison between these individuals and
with previously recovered specimens. CT scans of long bones and foot
bones show developmental features such as density gradients that
reveal ossification centers. The braincase of Khroma was segmented to
show the approximate morphology of the brain; its volume is slightly
less (∼2,300 cm3) than that of neonate elephants (∼2,500 cm3). Lyuba's
premaxillae are more gracile than those of Khroma, possibly a result
of temporal and/or geographic variation but probably also reflective
of their age difference. Segmentation of CT data and 3-D modeling
software were used to produce models of teeth that were too complex
for traditional molding and casting techniques.

**

Also, in the same issue of the Journal of Paleontology 88(4), other
vertpaleo papers:



http://www.bioone.org/toc/pleo/88/4


Virtual reconstruction of endocast anatomy in early ray-finned fishes
(Osteichthyes, Actinopterygii)
Sam Giles and Matt Friedman
Journal of Paleontology Jul 2014 : Vol. 88, Issue 4, pg(s) 636-651
doi: 10.1666/13-094
====
Endocranial anatomy of a new fossil porpoise (Odontoceti, Phocoenidae)
from the Pliocene San Diego Formation of California
Rachel A. Racicot and Timothy Rowe
Journal of Paleontology Jul 2014 : Vol. 88, Issue 4, pg(s) 652-663
doi: 10.1666/13-109
==
Developmental paleobiology of the vertebrate skeleton
Martin Rücklin, Philip C. J. Donoghue, John A. Cunningham, Federica
Marone, and Marco Stampanoni
Journal of Paleontology Jul 2014 : Vol. 88, Issue 4, pg(s) 676-683
doi: 10.1666/13-107

---------- Forwarded message ----------
From: Ben Creisler <bcreisler@gmail.com>
Date: Wed, Jul 9, 2014 at 8:12 AM
Subject: Baby mammoths get CT scans
To: dinosaur@usc.edu, VRTPALEO@usc.edu


Ben Creisler
bcreisler@gmail.com


The new issue of the Journal of Paleontology is apparently not online
yet but these news stories are out about new studies of two baby
woolly mammoths:


http://phys.org/news/2014-07-ct-scanned-siberian-mammoth-calves-yield.html

http://www.nbcnews.com/science/science-news/x-ray-scans-tell-tale-baby-mammoths-life-death-n150991