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Lower Pliocene hominid remains from Sterkfontein
T C Partridge1, D E Granger, M W Caffee
1Sterkfontein Research Unit and Climatology Research Group, University of the Witwatersrand, Private Bag 3, WITS 2050, Johannesburg, South Africa. tcp@iafrica.com
Science (New York, N.Y.)
|April 26, 2003
Summary
Cosmogenic dating of Sterkfontein cave fossils reveals hominid accumulation in the Lower Pliocene. Key fossils, like StW 573, are approximately 4 million years old, similar to East African Australopithecus anamensis.
Area of Science:
- Paleoanthropology and geology
- Utilizing cosmogenic nuclides for geochronology
Background:
- Sterkfontein Caves in South Africa is a significant paleoanthropological site.
- Previous dating efforts have aimed to establish a timeline for hominid fossil discoveries.
Observation:
- Low-lying fossiliferous breccia in Sterkfontein Caves was analyzed.
- Cosmogenic aluminum-26 and beryllium-10 isotopes were used for burial dating.
Findings:
- Hominid fossils associated with the breccia accumulated during the Lower Pliocene epoch.
- The skeleton StW 573 and new specimens from Jacovec Cavern date to approximately 4 million years ago.
- These South African hominid fossils are contemporaneous with Australopithecus anamensis from East Africa.
Implications:
- Establishes a precise age for crucial hominid fossils from Sterkfontein.
- Provides new insights into the early evolution and dispersal of hominids.
- Facilitates comparative studies between South and East African hominid populations.
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