27 July 2007

Measuring the great white’s bite

By
Cosmos Online
Using sophisticated computer software Australian researchers are measuring the bite force of the great white shark for the first time.
Measuring the great white's bite

Mighty bite: The researchers used a CT scanner to to generate 3-D images of a recently-netted great white's internal anatomy. Now they are plugging the data into sophisticated computer software to reveal the fish's maximum bite force. Credit: Stephen Wroe

SYDNEY: Using sophisticated computer software researchers are measuring the bite force of the great white shark for the first time.

The study will reveal what forces and behaviours the carnivore’s skull is adapted to handle and will help resolve competing theories about its feeding behaviour.

Though bite force has been measured in some living individuals before now, the techniques used have been relatively unsophisticated and researchers suspect they have not been able to determine the maximum bite force the species is capable of.

Skull stresses

“Almost nothing is known about the bite force and skull mechanics of great white sharks,” said biomechanics expert Stephen Wroe of the University of New South Wales in Sydney, Australia. “With the new technology will come new theoretical thresholds for the great white’s abilities.”

Along with scientists at the University of Newcastle in New South Wales, Wroe’s team have developed software that provides a three-dimensional look at the stresses placed on the skull and jaw of the much-maligned sea creature.

To perfect their model the team carried out a detailed CT scan (computed tomography) of the muscles and bones of a 2.4-metre-long great white (Carcharodon carcharias) that died tangled in netting off the northern coast of NSW last year. Since then it has been frozen awaiting analysis.

“It is very important to have a detailed understanding of what the major predators in our world are capable of… in order to appreciate how they fit into their environment, as well as how they have evolved to do so,” said shark expert Dan Huber from University of South Florida in Tampa, USA.

Shark-proof mesh

Huber is working with the Australian team to determine whether sharks such as the great white could be responsible for damaging marine cables and communication systems on U.S. navy submarines.

“If we are going to invest any effort in developing various marine technologies that are safe from sharks, whether they be transoceanic cables or shark-proof meshes for life guards, we need to know exactly what the sharks are capable of,” Huber told Cosmos Online. “It doesn’t make much sense to build a structure without knowing what kinds of forces the structure is going to have to withstand.”

Wroe’s team now hope to use the analysis to study the bite force of an extinct relative of the great white, the monstrous Charcharodon megalodon which grew to 16 m in length and weighed up to 30 tonnes. The species died out 1.6 million years ago and is thought to have been the largest predatory fish ever to have lived.

NEWSLETTER

Sign up to our free newsletter and have "This Week in Cosmos" delivered to your inbox every Monday.

>> More information
Latest
issue
CONNECT
Like us on Facebook
Follow @COSMOSmagazine
Add COSMOS to your Google+ circles