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Eyasi 1 and the suprainiac fossa
1Department of Anthropology, Washington University, St. Louis, Missouri 63130, USA. trinkaus@artsci.wustl.edu
American Journal of Physical Anthropology
|April 16, 2004
Summary
A reexamination of the Eyasi 1 fossil reveals unique features previously thought exclusive to Neandertals. This finding suggests these traits are more widespread among archaic humans than previously understood.
Area of Science:
- Paleoanthropology
- Human Evolution
- Osteology
Background:
- The Eyasi 1 neurocranium is a significant fossil from the later Middle Pleistocene of East Africa.
- Certain midoccipital features, like the suprainiac fossa, were historically considered exclusive to European and West Asian Neandertals.
Purpose of the Study:
- To reexamine the Eyasi 1 neurocranium for specific midoccipital features.
- To assess the distribution of these features beyond the Neandertal lineage.
Main Methods:
- Detailed osteological reexamination of the Eyasi 1 neurocranium.
- Comparative analysis of identified features with known archaic human specimens.
Main Results:
- The Eyasi 1 exhibits a modest nuchal torus, absent external occipital protuberance, and a distinct suprainiac fossa.
- These features, particularly the suprainiac fossa, challenge their exclusive association with Neandertals.
Conclusions:
- The presence of Neandertal-like features in East African archaic humans broadens our understanding of hominin diversity.
- These traits should be evaluated within broader frequency distributions across later archaic human populations.
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