Analysis of chemical traces in fossilized teeth shows that Australopithecus ate plants similar to those consumed by herbivorous animals of the same time period, rather than meat like predators.
Mechanism
Synthesis from 1 study
When early humans ate mostly grasses and leaves, the chemicals from those plants got locked into their teeth as they grew, making their teeth look chemically similar to other plant-eating animals. This happened because the plants they ate had a different chemical fingerprint than meat, and their...
Most probable mechanism
When an animal eats mostly grasses and leaves, the carbon and nitrogen in those plants get incorporated into its teeth as it grows, making the chemical signature of its enamel look like that of other plant-eating animals. This happens because the types of carbon and nitrogen in plants from open grasslands are different from those in meat or fruits, and the body doesn’t change these elements much when building teeth.
Dietary intake of C4 grasses and sedges provides carbon isotopes with a distinct signature compared to C3 plants or animal tissues.
Carbon isotopes from consumed vegetation are incorporated into enamel hydroxyapatite during tooth mineralization without isotopic fractionation.
Nitrogen isotopes from plant proteins are retained in enamel through metabolic pathways that reflect the nitrogen composition of the local plant community.
The resulting isotopic composition of tooth enamel matches that of contemporaneous herbivorous mammals consuming the same local vegetation.
Evidence from Studies
Supporting (1)
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Australopithecus at Sterkfontein did not consume substantial mammalian meat.
Contradicting (0)
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Gold Standard Evidence Needed
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