Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Toothsome Research: Deducing the Diet of a Prehistoric Hominid

12.02.2009
In an unusual intersection of materials science and anthropology, researchers from the National Institute of Standards and Technology (NIST) and The George Washington University (GWU) have applied materials-science-based mathematical models to help shed light on the dietary habits of some of mankind’s prehistoric relatives.

Their work forms part of a newly published, multidisciplinary analysis* of the early hominid Australopithecus africanus by anthropologists at the State University of New York at Albany and elsewhere.

In the new study, Albany researcher David Strait and his colleagues** applied finite element analysis—an engineer’s modeling tool that employs an intricate geometric mesh to calculate the stresses and strains at play in complex shapes—to the teeth and jaws of A. africanus, an African hominid that lived 2 to 3 million years ago. Their goal was to determine just how, and with how much force, the animal chomped and chewed its food.

Such analyses are of great importance to anthropologists. Teeth are the hardest parts of the body, and so are the parts most likely to be found after millions of years. Careful examination of subtle features of teeth and jaws can reveal what an animal could eat, which implies what it did eat, which implies a host of things about its environment, habits and survival strategies.

A. africanus presented a puzzle. Classical analysis of the skull—large molars and premolars with thick enamel, thick heavy jawbones, strong chewing muscles as evidenced by their anchor points on the bone—pointed to a diet of small, hard seeds. The finite-element analysis threw a spanner in the works. It suggested that A. africanus’s facial and jaw anatomy was optimized to handle stress on the premolars, teeth located farther forward in the mouth and most useful for chewing larger hard objects. But recent studies had shown that the teeth lacked the microscopic wear patterns characteristic of chewing hard objects, a contradiction.

Here, work by NIST researcher Brian Lawn and a group at GWU headed by Peter Lucas came in handy. Driven by an interest in tooth restoration materials, they had been studying teeth using fracture mechanics, a field that considers how materials fail under excessive loads. “Our analytical approach produces equations that predict how each mode of damage will occur under different conditions and this enables us to determine trends for different tooth sizes, different food sizes, different food hardness and so on,” explained Lawn. “What they show is that, under some conditions, teeth will actually fracture before they wear.” This explained the absence of microwear patterns in the teeth, which would normally not be used for chewing small hard seeds. “A lot of people have thought the most important part of the survival of the tooth is wear, but it’s now becoming evident that the fracture properties are also very important because there’s a limit to the force that you can apply. Wear is important, but when you start to bite on harder, larger objects, fracture becomes more important,” Lawn said.

“This is a neat example of how really basic materials science—fracture mechanics—has important implications for biological sciences and anthropology,” Strait observed. In the bigger picture, said Strait, the new understanding about A. africanus’s diet may help to explain its successful adaptation to changing climates. A large hard nut that had to be cracked with the premolars may not have been a preferred meal, but it could be something to fall back on when other foods were scarce.

Read more about the study in the SUNY Albany news release, “Early Humans Were Nuts About Seeds.”

* D.S. Strait, G.W. Weber, S. Neubauer, J. Chalk, B.G. Richmond, P.W. Lucas, M.A. Spencer, C. Schrein, P.C. Dechow, C.F. Ross, I.R. Grosse, B.W. Wright, P. Constantino, B.A. Wood, B. Lawn, Q. Wang, D.E. Slice, C. Byron and A.L. Smith. The feeding biomechanics and dietary ecology of Australopithecus africanus. Proceedings of the National Academy of Sciences. Published online Feb. 2, 2009, doi:10.1073/pnas.0808730106

** Contributors to the complex effort included researchers from the State University of New York at Albany, the University of Vienna, the Max-Planck-Institute for Evolutionary Anthropology, the Smithsonian Institution, Arizona State University, Baylor College of Dentistry, the University of Chicago, the University of Massachusetts, the Kansas City University of Medicine and Biosciences, the Mercer University School of Medicine and Mercer University as well as NIST and The George Washington University.

Michael Baum | Newswise Science News
Further information:
http://www.nist.gov

More articles from Materials Sciences:

nachricht Decoding cement's shape promises greener concrete
08.12.2016 | Rice University

nachricht Scientists track chemical and structural evolution of catalytic nanoparticles in 3-D
08.12.2016 | DOE/Brookhaven National Laboratory

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>