Allosaurus head and neck function (free pdf)

[Ben Creisler <bcreisler@gmail.com>]

From: Ben Creisler
bcreisler@gmail.com

New in open-access Palaeontologia Electronica:


Eric Snively, John R. Cotton, Ryan Ridgely, and Lawrence M. Witmer (2013)
Multibody dynamics model of head and neck function in Allosaurus
(Dinosauria, Theropoda).
Palaeontologia Electronica Vol. 16, Issue 2; 11A 29p
palaeo-electronica.org/content/2013/389-allosaurus-feeding
http://palaeo-electronica.org/content/2013/389-allosaurus-feeding


We present a multibody dynamics model of the feeding apparatus of the
large Jurassic theropod dinosaur Allosaurus that enables testing of
hypotheses about the animal's feeding behavior and about how
anatomical parameters influence function. We created CT- and
anatomical-inference-based models of bone, soft tissue, and air spaces
which we use to provide inertial properties for musculoskeletal
dynamics. Estimates of bone density have a surprisingly large effect
on head inertial properties, and trachea diameter strongly affects
moments of inertia of neck segments for dorsoventral movements. The
ventrally-placed insertion of m. longissimus capitis superficialis in
Allosaurus imparted over twice the ventroflexive accelerations of a
proxy control insertion lateral to the occipital condyle, the latter
being its position in nearly all other theropods. A feeding style that
involved defleshing a carcass by avian-raptor-like retraction of the
head in Allosaurus is more probable than is lateroflexive
shake-feeding, such as that seen in crocodilians and inferred for
tyrannosaurids.