Navigation Links
Early humans had 'jaws of steel'
Date:2/3/2009

TEMPE, Ariz. Your mother always told you not to use your teeth as tools to open something hard, and she was right. Human skulls have small faces and teeth and are not well-equipped to bite down forcefully on hard objects. Not so of our earliest ancestors, say scientists. New research published in the February 2009 issue of Proceedings of the National Academy of Sciences reveals nut-cracking abilities in our 250-million-year-old relatives that enabled them to alter their diet to adapt to changes in food sources in their environment.

Mark Spencer, an Arizona State University assistant professor, and doctoral student Caitlin Schrein in ASU's School of Human Evolution and Social Change, are part of the international team of researchers who devised the study featured in the article "The feeding biomechanics and dietary ecology of Australopithecus africanus." Using state-of-the-art computer modeling and simulation technology the same kind engineers use to simulate how a car reacts to forces in a front-end collision evolutionary scientists built a virtual model of the A. africanus skull and were able to see just how the jaw operated and what forces it could produce.

"We started with a CT scan of a skull that is one of the most complete specimens of A. africanus that we have," said Spencer, researcher in ASU's Institute of Human Origins and a lead investigator on the project, which was funded by the National Science Foundation and European Union. This would be a later ancestor of Lucy STS5 - who is affectionately known as "Mrs. Ples." The skull, discovered in 1947, has struts on the side of the nose, but no teeth. "We meshed those data with another specimen with teeth to make the virtual model of the bone and tooth structure.

"Then we looked at chimpanzees, who share common features with Australopithecus, and took measurements of how their muscles work and added that to the model. We were able to validate this model by comparing it to a similar model built for a species of monkey called macaques," Spencer explained.

The result a rainbow colored virtual skull that illustrates forces absorbed by the cranial structure in simulated bite scenarios and how their unusual facial features were ideally suited to support the heavy loads of cracking hard nuts.

"It was like watching 'Mrs. Ples' come to life," Spencer said.

"This reinforces the body of research indicating that facial specializations in species of early humans are adaptations due to a specialized diet," said Spencer. "The enlargement of the premolars, the heavy tooth enamel and the evidence now that they were loading forcefully on the molars suggest the size of the objects were larger than the previously hypothesized small seeds and nuts.

"These fall-back foods hard nuts and seeds were important survival strategies during a period of changing climates and food scarcity," he added. "Our research shows that early, pre-stone tool human ancestors solved problems with their jaws that modern humans would have solved with tools."

Human Evolution and Social Change, are part of the international team of researchers who devised the study featured in the article "The feeding biomechanics and dietary ecology of Australopithecus africanus." Using state-of-the-art computer modeling and simulation technology the same kind engineers use to simulate how a car reacts to forces in a front-end collision evolutionary scientists built a virtual model of the A. africanus skull and were able to see just how the jaw operated and what forces it could produce.

"We started with a CT scan of a skull that is one of the most complete specimens of A. africanus that we have," said Spencer, researcher in ASU's Institute of Human Origins and a lead investigator on the project, which was funded by the National Science Foundation and European Union. This would be a later ancestor of Lucy STS5 - who is affectionately known as "Mrs. Ples." The skull, discovered in 1947, has struts on the side of the nose, but no teeth. "We meshed those data with another specimen with teeth to make the virtual model of the bone and tooth structure.

"Then we looked at chimpanzees, who share common features with Australopithecus, and took measurements of how their muscles work and added that to the model. We were able to validate this model by comparing it to a similar model built for a species of monkey called macaques," Spencer explained.

The result a rainbow colored virtual skull that illustrates forces absorbed by the cranial structure in simulated bite scenarios and how their unusual facial features were ideally suited to support the heavy loads of cracking hard nuts.

"It was like watching 'Mrs. Ples' come to life," Spencer said.

"This reinforces the body of research indicating that facial specializations in species of early humans are adaptations due to a specialized diet," said Spencer. "The enlargement of the premolars, the heavy tooth enamel and the evidence now that they were loading forcefully on the molars suggest the size of the objects were larger than the previously hypothesized small seeds and nuts.

"These fall-back foods hard nuts and seeds were important survival strategies during a period of changing climates and food scarcity," he added. "Our research shows that early, pre-stone tool human ancestors solved problems with their jaws that modern humans would have solved with tools."


'/>"/>

Contact: Jodi Guyot
jodi.guyot@asu.edu
480-727-8739
Arizona State University
Source:Eurekalert  

Related biology news :

1. 60 second test could help early diagnosis of common brain diseases
2. Restless legs syndrome affects nearly 2 percent of US/UK children
3. Bleeding, not inflammation, is major cause of early lung infection death
4. Pig study sheds new light on the colonisation of Europe by early farmers
5. Color contrast is seen by the brain early doors
6. Extra gene copies were enough to make early humans mouths water
7. Was ability to run early mans Achilles heel?
8. New technique can be breakthrough for early cancer diagnosis
9. Yam bean a nearly forgotten crop
10. NIH awards nearly $23M to University of Chicago for translational research
11. Yam bean a nearly forgotten crop
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Early humans had 'jaws of steel'
(Date:10/4/2017)... Solutions, a global clinical research organization (CRO), announces the launch of ... 4, 2017. Shadow is designed to assist medical writers and biometrics ... the European Medicines Agency (EMA) in meeting the requirements for de-identifying ... ... ...
(Date:6/23/2017)... and ITHACA, N.Y. , ... and Cornell University, a leader in dairy research, today ... bioinformatics designed to help reduce the chances that the ... the onset of this dairy project, Cornell University has ... for Sequencing the Food Supply Chain, a food safety ...
(Date:5/6/2017)... , May 5, 2017 ... just announced a new breakthrough in biometric authentication ... exploits quantum mechanical properties to perform biometric authentication. These ... smart semiconductor material created by Ram Group and ... finance, entertainment, transportation, supply chains and security. Ram ...
Breaking Biology News(10 mins):
(Date:10/12/2017)... ... October 12, 2017 , ... AMRI, a ... biotechnology industries to improve patient outcomes and quality of life, will now be ... are being attributed to new regulatory requirements for all new drug products, including ...
(Date:10/11/2017)... ... 2017 , ... At its national board meeting in North ... the co-founder, CEO and chief research scientist of Minnesota-based Advanced Space Technology and ... ARCS Alumni Hall of Fame . ASTER Labs is a technology development ...
(Date:10/11/2017)... ... ... a basic first aid supply for any work environment, but most personal eye wash can ... a dangerous substance enters both eyes? It’s one less decision, and likely quicker response time ... , “Whether its dirt and debris, or an acid or alkali, getting anything in your ...
(Date:10/11/2017)... Md. (PRWEB) , ... October 11, 2017 , ... ... digital pathology, announced today it will be hosting a Webinar titled, “Pathology is ... Advanced Pathology Associates , on digital pathology adoption best practices and how Proscia ...
Breaking Biology Technology: