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Tous les fossiles de la lignée

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Tous les fossiles de la lignée

humaine sont bipèdes.

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Théorie ancienne et fausse d'un

redressement progressif.

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450 → 1300

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Pan Paranthropus Homo

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Y5

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Chemicals found in any animal come from what it ingests, such as plants. Plants turn sunlight into energy using

photosynthesis, but they rely on two slightly different forms of the process. The two approaches add different amounts of the isotope carbon 13 to the plants' leaves. Bushes, shrubs and trees have less carbon 13 in their fruit or leaves than savanna grasses. The chemicals in the food eaten by P. robustus,

including the isotope, were incorporated into the enamel of the hominid's permanent teeth as they formed.

Sponheimer and his colleagues used a laser to remove

samples from each of the four P. robustus teeth, leaving only small marks on the precious specimens. Then, they analyzed the carbon isotope ratio in the samples. The researchers

report that Paranthropus ate a variety of foods, perhaps

grasses, tubers and even animals – and what they ate varied seasonally and from hominid to hominid.

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Les cladogrammes des élèves

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1470 1813

habilis ss

rudolfensis

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Paranthropus

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Les origines géographiques

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Erectus

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L'Ève

mitochondriale

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Sapiens

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