Featured Research

from universities, journals, and other organizations

Removing doubt over croc snout clout

Date:
January 18, 2013
Source:
Monash University
Summary:
Researchers have shown how the shape of a crocodile's snout could determine its ability to feast on certain types of prey, from large mammals to small fish.

Dr Colin McHenry.
Credit: Image courtesy of Monash University

Researchers have shown how the shape of a crocodile's snout could determine its ability to feast on certain types of prey, from large mammals to small fish.

Led by Dr Colin McHenry and PhD student Chris Walmsley, from Monash University's School of Biomedical Sciences, a team of researchers compared the jaw strength of different types of crocodiles when feeding on large prey. Using computer technology they subjected the jaws to the sorts of biting, shaking, and twisting loads that crocodiles use to feed on large prey. The team generated 3D images showing the strain measured on the jaws of seven diverse species of crocodile.

They found the lower jaws of short-snouted crocodiles performed well under the loads applied to mimic the feeding behaviour on large prey, but those with elongated jaws were more likely to break under the same loads, showing their limited ability to feed on large prey.

Detailed January 17 in PLoS One, the findings contribute to the understanding of how the shape of the crocodile's skull correlates with strength. It is the first study of its kind to investigate the mechanics that underlie the link between the shape of the lower jaw and diet.

"The notion that long, narrow snouted crocodiles feed primarily on fish or small prey is well established, but the biomechanics of the crocodiles' lower jaw, the mandible, have not been previously explored," Mr Walmsley said.

"To test the jaw biomechanics of large crocodiles we used a computational engineering approach, called Finite Element Analysis, that is widely used to design planes, cars, boats, buildings, bridges and many other structures.

"We found that mandible shape correlated consistently with jaw biomechanics. This means that the lower jaws of long-snouted species were not as strong and more likely to break during feeding on large prey. It's therefore no surprise that they tend to concentrate on small, agile, aquatic prey whilst shorter and more robust-snouted animals are capable of taking much larger prey."

Dr McHenry said the findings were relevant to a broad range of aquatic predators including dolphins and fossil marine reptiles.

"Interestingly the amount of strain a jaw was under was directly proportional to the length of the symphysis, which is the joint between two halves of the lower jaw. This means the animal's biomechanical response to force could be accurately predicted by knowing the length of its chin.

"Killer whales, alligators and salt-water crocodiles can all feed on large prey. In all of these species the symphysis is a small proportion of the length of the jaw. Whereas, fish-eating crocodiles and dolphins have long, narrow chins."

Dr McHenry said further research was needed to explain why crocodiles that feed on small prey had elongated snouts.

"We suspect the answer lies in the hydrodynamic efficiency of the elongate jaws, and we plan to explore this further using other computational engineering techniques," Dr McHenry said.

The study was led by Monash University in collaboration with the University of Newcastle, the University of New South Wales and the University of Chicago, US.


Story Source:

The above story is based on materials provided by Monash University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Christopher W. Walmsley, Peter D. Smits, Michelle R. Quayle, Matthew R. McCurry, Heather S. Richards, Christopher C. Oldfield, Stephen Wroe, Phillip D. Clausen, Colin R. McHenry. Why the Long Face? The Mechanics of Mandibular Symphysis Proportions in Crocodiles. PLoS ONE, 2013; 8 (1): e53873 DOI: 10.1371/journal.pone.0053873

Cite This Page:

Monash University. "Removing doubt over croc snout clout." ScienceDaily. ScienceDaily, 18 January 2013. <www.sciencedaily.com/releases/2013/01/130118235050.htm>.
Monash University. (2013, January 18). Removing doubt over croc snout clout. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2013/01/130118235050.htm
Monash University. "Removing doubt over croc snout clout." ScienceDaily. www.sciencedaily.com/releases/2013/01/130118235050.htm (accessed July 29, 2014).

Share This




More Plants & Animals News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Rodents Rampant in Gardens Around Louvre

Rodents Rampant in Gardens Around Louvre

AP (July 29, 2014) Food scraps and other items left on the grounds by picnickers brings unwelcome visitors to the grounds of the world famous and popular Louvre Museum in Paris. (July 29) Video provided by AP
Powered by NewsLook.com
Deadly Ebola Virus Threatens West Africa

Deadly Ebola Virus Threatens West Africa

AP (July 28, 2014) West African nations and international health organizations are working to contain the largest Ebola outbreak in history. It's one of the deadliest diseases known to man, but the CDC says it's unlikely to spread in the U.S. (July 28) Video provided by AP
Powered by NewsLook.com
Traditional African Dishes Teach Healthy Eating

Traditional African Dishes Teach Healthy Eating

AP (July 28, 2014) Classes are being offered nationwide to encourage African Americans to learn about cooking fresh foods based on traditional African cuisine. The program is trying to combat obesity, heart disease and other ailments often linked to diet. (July 28) Video provided by AP
Powered by NewsLook.com
Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Newsy (July 28, 2014) The asteroid that killed the dinosaurs struck at the worst time for them. A new study says that if it hit earlier or later, they might've survived. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins