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Published on: November 4, 2025
Morphological affinities of the Sahelanthropus tchadensis (Late Miocene hominid from Chad) cranium
Franck Guy1, Daniel E Lieberman, David Pilbeam
1Laboratoire de Géobiologie, Biochronologie et Paléontologie Humaine, Centre National de la Recherche Scientifique Unité Mixte de Recherche 6046, Faculté des Sciences, Université de Poitiers, 40 Avenue du Recteur Pineau, 86022 Poitiers Cedex, France.
Abstract:
The recent reconstruction of the Sahelanthropus tchadensis cranium (TM 266-01-60-1) provides an opportunity to examine in detail differences in cranial shape between this earliest-known hominid, African apes, and other hominid taxa. Here we compare the reconstruction of TM 266-01-60-1 with crania of African apes, humans, and several Pliocene hominids. The results not only confirm that TM 266-01-60-1 is a hominid but also reveal a unique mosaic of characters. The TM 266-01-60-1 reconstruction shares many primitive features with chimpanzees but overall is most similar to Australopithecus, particularly in the basicranium. However, TM 266-01-60-1 is distinctive in having the combination of a short subnasal region associated with a vertical upper face that projects substantially in front of the neurocranium. Further research is needed to determine the evolutionary relationships between Sahelanthropus and the known Miocene and Pliocene hominids.
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