Wednesday, October 21, 2009

2 Million Year Old Tool-Making Hominins Inhabited Grasslands

Oldest Evidence of Toolmaking Hominins in a Grassland - Dominated Ecosystem. 2009. Plummer, T.W., et al. PLoS ONE 4(9): e7199.
Scientists have announced the discovery of the oldest archeological evidence of early human activities in a grassland environment, dating to 2 million years ago.

Tor by Joe Kubert
The researchers provide the first documentation of both at the 2-million-year-old Oldowan archeological site of Kanjera South, Kenya, which has yielded both Oldowan artifacts and well-preserved faunal remains, allowing researchers to reconstruct past ecosystems.

The study documents what was previously speculated based on indirect evidence – that grassland-dominated ecosystems did, in fact, exist during the Plio-Pleistocene (ca. 2.5-1.5 million years ago) and that early human tool-makers were active in open settings.

A scatter of fossils and artifacts on pedestals within a grid of one meter squares. Photo: T. Plummer
Other recent research shows that the Kanjera hominins obtained meat and bone marrow from a variety of animals and that they carried stone raw materials over surprisingly long distances in this grassland setting. A comparison with other Oldowan sites shows that by 2.0 million years ago, hominins, almost certainly of the genus Homo, lived in a wide range of habitats in East Africa, from open grassland to woodland and dry forest. link