High-tech Tests Allow Anthropologists To Track Ancient Hominids Across The Landscape

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Source: ScienceDaily (Feb. 13, 2009)

Dazzling new scientific techniques are allowing archaeologists to track the movements and menus of extinct hominids through the seasons and years as they ate their way across the African landscape, helping to illuminate the evolution of human diets.

Piecing together relationships between the diets of hominids several million years ago to that of early and modern humans is allowing scientists to see how diet relates to the evolution of cognitive abilities, social structures, locomotion and even disease, said University of Colorado at Boulder anthropology Professor Matt Sponheimer. Sponheimer organized a session titled "The Evolution of Human Diets" at the annual American Association for the Advancement of Science meeting Feb. 12-15 in Chicago.

Sponheimer specializes in stable isotope analysis, comparing particular forms of the same chemical element, like carbon, present in fossil remains to help reconstruct past lives of hominids. Zapping hominid teeth with lasers, for example, frees telltale carbon gases from the enamel, allowing scientists to pinpoint the types of plants consumed by the hominids and the environments where they lived, said Sponheimer, who also relies on the microscopic wear of ancient hominid teeth for data on food consumption.

"Darwin surmised more than 150 years ago in 'The Descent of Man' that changes in the subsistence or environment of human ancestors likely led to the advent of modern humans," Sponheimer said. "Dietary resources can be a force for evolution."

One hominid genus under study by Sponheimer is the 2 million-year-old Paranthropus, a short, upright member of the australopithecine family that includes the Ethiopian fossil, Lucy. Discovered in 1974, Lucy, believed to be roughly 3 million years old, is regarded by many anthropologists as the matriarch of modern humans.

http://www.sciencedaily.com/releases/2009/02/090212150838.htm