By analyzing the microscopic holes and scratches on the teeth of hominids and stable carbon isotopes in teeth, researchers get a very different picture of early hominid foraging habitats that painted the physical structure of the skull, jaw and teeth. While some trees hominid molars and powerful jaws - including Paranthropus boisei, known as "Nutcracker Man" - they may have cracks nuts a few times in any case, said Matt Sponheim University of Colorado professor of anthropology, co-author of the study.
These findings forced anthropologists to rethink long-held assumptions about early hominids, aided by technological tools that were unknown a few years ago. A paper on the subject by Sponheim and co-author Peter Ungar, an eminent professor at the University of Arkansas, was published in October 14 issue of Science.
Earlier this year, Sponheim and colleagues have shown Paranthropus boisei was mainly feed on grasses and sedges, instead of soft fruits preferred by chimpanzees. "We can now rest assured that Paranthropus boisei ate foods that would be self-respecting chimp stomach in quantity," said Sponheim. "It is also clear that our previous ideas on the diet of this group was grossly simplistic better, and right now the worst. "
"The morphology indicates that you may have eaten a hominid," said Ungar. But this does not necessarily indicate that the animal was actually eating, he said.
While studies dental microwear Ungar - the microscopic pits and scratches, which reveals that the food left behind the teeth - studies of stable carbon isotopes in teeth Sponheim. Through the analysis of stable carbon isotopes obtained from small portions of animal teeth, researchers can determine whether the animals were eating foods that use different photosynthetic pathways, which convert sunlight into energy.
Paranthropus boisei teeth results, this year, reported that they ate the food on the so-called C4 photosynthesis, which refers to the consumption of grasses and sedges. The analysis of the different stands on the closest relatives of humans, chimpanzees and gorillas like to eat the food so-called path of C3 shows a synthetic diet that included trees and shrubs.
Dental isotopic studies micro-wear and stable also highlight potentially important differences in diet between the hominids of southern and eastern Africa, said Sponheim, a finding that was not expected, given their strong anatomical similarities. "I honestly do not think anyone would have predicted such strong regional differences," said Sponheim. "But it is one of the things that are funny on Science - Nature often reminds us that there is much we do not yet understand.
"The key is that our old answers on the diets of hominids are no longer sufficient, and we really need to start looking in directions that would have been considered crazy, even a decade ago," said Sponheim. "We see a lot more evidence on the change in diet between our hominid line than previously appreciated. Therefore, the whole concept of the hominid diet is really problematic, because different species may have used fundamentally different . "
While new technologies have led to new discoveries in the field of biological anthropology are not restricted for use in human ancestors, the researchers said. Animals in the study using simulation techniques new teeth ranging from rodents and marsupials dinosaur age, Sponheim said.
