This page outlines some general questions and answers to give you an idea of the kind of research we carry out, and the kinds of questions we are attempting to answer - it's still work in progress....
How do you work out how an extinct animal functioned?
All animals, extinct or alive, are subject to
the same physical principles, such as they must deal with
the laws of gravity, and create skeletal structures that
are strong enough to support their bodies, yet not too
costly, in terms of material, to build and carry around. My
group and I apply these principles to extinct animals to
work out features such as how fast or how forcefully jaws
moved, place boundaries on the range of functions animals
can undertake, study how well adapted a particular feature
is for a particular function, and explore what other
constraints evolution may place on the shape and function
of the animal skeleton.
One only has to look at the success of TV
programmes such as Walking with Dinosaurs to see that the
public are fascinated with the lifestyles of extinct
animals. Our research goes far beyond this however, and as
I elude to above, we're interested not only in individual
animal function, but also large-scale patterns of how
functions evolve over time, whether animals do follow
biomechanical predictions, and if they do not, what other
factors are controlling the shape of their skeleton.
What we ultimately hope to achieve with this research is
(i) an idea of how morphology (that is shape, or form)
changes over evolutionary timescales by interactions
between function, the environment, developmental processes,
and the genetic material the animal has available to it in
the first place; (ii) and how diversity in function (and
perhaps ecology) relates to species diversity over time,
and what role external environmental factors play.
How do you
use different techniques?
We frequently use X-ray computed tomography
scanning (CT scanning) to capture the external and internal
features of a specimen. CT scanning uses X-rays to capture
a series of 2D images that are then computationally
assembled into a 3D dataset. This 3D data can then be used
to visualise the internal anatomy of the specimen, and used
as the basis for performing further functional analysis,
such as finite element analysis (FEA). FEA is a technique
that computes how a structure, like a fossil, stresses and
strains when it is performing a function such as feeding or
walking. From these models we can get an idea of the type
of behaviour an extinct animal could perform, and why its
skeleton was shaped in a particular way.