Pleistocene climatic variability in eastern Africa influenced hominin evolution: the 620,000-year climate record from Chew Bahir
- 1Institute of Geography Education, University of Cologne, Cologne, Germany (v.foerster@uni-koeln.de)
- 2Department of Mining and Geological Engineering, Botswana International University of Science and Technology, Palapye, Botswana
- 3School of Earth Sciences, Addis Ababa University, Addis Ababa, Ethiopia
- 4Research Laboratory for Archaeology and the History of Art, University of Oxford, Oxford, UK
- 5Large Lakes Observatory and Department of Earth & Environmental Sciences, University of Minnesota Duluth, Duluth, MN, USA
- 6Berkeley Geochronology Center, Berkeley, CA, USA
- 7Department of Archaeology, Classics and Egyptology, University of Liverpool, Liverpool, UK
- 8MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
- 9Department of Geoscience, Eberhard Karls Universität Tübingen, Tübingen, Germany
- 10Senckenberg Centre for Human Evolution and Palaeoenvironment, University of Tübingen, Tübingen, Germany
- 11Institute of Geosciences, University of Potsdam, Potsdam, Germany
- 12Department of Geography, University of Cambridge, Cambridge, UK
- 13Institute for Geography, University of Cologne, Cologne, Germany
- 14LacCore/CSDCO, Department of Earth and Environmental Sciences, University of Minnesota, Minnesota, MN, USA
- 15Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, UK
- 16Unit of Evolutionary Biology/Systematic Zoology, University of Potsdam, Potsdam, Germany
- 17Institute of Prehistoric Archaeology, University of Cologne, Cologne, Germany
- 18Department of Geosciences, University of Arizona, Tucson, AZ, USA
As a contribution towards a regional environmental context of human-climate interactions, the ICDP co-funded Chew Bahir Drilling Project, a part of the HSPDP (Hominin Sites and Paleolakes Drilling Project), recovered ~280-m long cores of sedimentary strata through continental scientific drilling in southern Ethiopia. The fluvio-lacustrine coring locality in the Chew Bahir basin is situated near key archaeological and paleoanthropological sites, such as the Omo-Kibish where the Omo 1 and 2 Homo sapiens fossils were recovered.
Here we present the 620,000-year environmental record from Chew Bahir that provides an extraordinary opportunity to examine the potential influence of climate variability on hominin evolution, cultural innovation and dispersal during the Middle to Late Pleistocene. The near-continuous Chew Bahir record documents 13 environmental episodes that differ in length and character, potentially inducing habitat changes influencing hominin biological and cultural transformation. We infer that long-lasting and relatively stable humid conditions from ~620,000–275,000 years BP (Episodes 1–6) were interrupted by several abrupt and extreme hydroclimatic oscillations. This phase coincided with the appearance of high anatomical diversity in hominin groups. During Episodes 7–9 (~275,000–60,000 years BP), a pronounced pattern of climatic cyclicity was paralleled by the gradual transition from Acheulean to Middle Stone Age technologies, the emergence of H. sapiens in eastern Africa, and a key phase of human social and cultural innovation. Episodes 10–12 (~60,000–10,000 years BP), marked by high-frequency climate oscillations, is contemporaneous with the global dispersal of H. sapiens, facilitated by continued technological innovation and the alignment of humid pulses between eastern Africa and the eastern Mediterranean.
Prospectively, the Chew Bahir record represents a crucial component for the Middle and Late Pleistocene in the ongoing efforts of the scientific community (future and upcoming ICDP-funded projects) to address questions in Africa across four topical core areas: paleoclimate, paleoenvironment, basin evolution, and modern lake systems.
How to cite: Foerster, V., Asrat, A., Bronk Ramsey, C., Brown, E. T., Deino, A., Grove, M., Hahn, A., Junginger, A., Kaboth-Bahr, S., Lane, C. S., Opitz, S., Noren, A., Roberts, H. M., Tiedemann, R., Vogelsang, R., Vidal, C. M., Cohen, A. S., Lamb, H. F., Schaebitz, F., and Trauth, M. H.: Pleistocene climatic variability in eastern Africa influenced hominin evolution: the 620,000-year climate record from Chew Bahir , EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-6170, https://doi.org/10.5194/egusphere-egu23-6170, 2023.
