By analyzing microscopic pits and scratches on hominid teeth, as well as stable isotopes of carbon found in teeth, researchers are getting a very different picture of the diet habitats of early hominids than that painted by the physical structure of the skull, jawbones and teeth.
While some early hominids sported powerful jaws and large molars -- including Paranthropus boisei, dubbed "Nutcracker Man" -- they may have cracked nuts rarely if at all, said CU-Boulder anthropology Professor Matt Sponheimer, study co-author.
Such findings are forcing anthropologists to rethink long-held assumptions about early hominids, aided by technological tools that were unknown just a few years ago. A paper on the subject by Sponheimer and co-author Peter Ungar, a distinguished professor at the University of Arkansas, was published in the Oct. 14 issue of Science.
Earlier this year, Sponheimer and his colleagues showed Paranthropus boisei was essentially feeding on grasses and sedges rather than soft fruits preferred by chimpanzees. "We can now be sure that Paranthropus boisei ate foods that no self-respecting chimpanzee would stomach in quantity," said Sponheimer. "It is also clear that our previous notions of this group's diet were grossly oversimplified at best, and absolutely backward at worst."
"The morphology tells you what a hominid may have eaten," said Ungar. But it does not necessarily reveal what the animal was actually dining on, he said.
While Ungar studies dental micro-wear -- the microscopic pits and scratches that telltale food leaves behind on teeth -- Sponheimer studies stable isotopes of carbon in teeth. By analyzing stable carbon isotopes obtained from tiny portions of animal teeth, researchers can determine whether the animals were eating foods that use different photosynthetic pathways that convert sunlight to energy.
The results for teeth from Paranthropus boisei, published earlier this year, indicated they were eating foods from the so-called C4 photosynthetic pathway, which points to consumption of grasses and sedges. The analysis stands in contrast to our closest human relatives like chimpanzees and gorillas that eat foods from the so-called C3 synthetic pathway pointing to a diet that included trees, shrubs and bushes.
Dental micro-wear and stable isotope studies also point to potentially large differences in diet between southern and eastern African hominids, said Sponheimer, a finding that was not anticipated given their strong anatomical similarities. "Frankly, I don't believe anyone would have predicted such strong regional differences," said Sponheimer. "But this is one of the things that is fun about science -- nature frequently reminds us that there is much that we don't yet understand.
"The bottom line is that our old answers about hominid diets are no longer sufficient, and we really need to start looking in directions that would have been considered crazy even a decade ago," Sponheimer said. "We also see much more evidence of dietary variability among our hominid kin than was previously appreciated. Consequently, the whole notion of hominid diet is really problematic, as different species may have consumed fundamentally different things."
While the new techniques have prompted new findings in the field of biological anthropology, they are not limited to use in human ancestors, according to the researchers. Current animals under study using the new tooth-testing techniques range from rodents and ancient marsupials to dinosaurs, said Sponheimer.
Much of Sponheimer's research on ancient hominids has been funded by the National Science Foundation.
Matt Sponheimer | EurekAlert!
Do microplastics harbour additional risks by colonization with harmful bacteria?
05.04.2018 | Leibniz-Institut für Ostseeforschung Warnemünde
Rutgers-led innovation could spur faster, cheaper, nano-based manufacturing
14.02.2018 | Rutgers University
At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.
Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...
Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.
Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...
University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.
Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
24.04.2018 | Information Technology
24.04.2018 | Earth Sciences
24.04.2018 | Life Sciences