TY  - JOUR
A1  - Lupien, Rachel L.
A1  - Russell, James M.
A1  - Pearson, Emma J.
A1  - Castaneda, Isla S.
A1  - Asrat, Asfawossen
A1  - Förster, Verena
A1  - Lamb, Henry F.
A1  - Roberts, Helen M.
A1  - Schäbitz, Frank
A1  - Trauth, Martin H.
A1  - Beck, Catherine C.
A1  - Feibel, Craig S.
A1  - Cohen, Andrew S.
T1  - Orbital controls on eastern African hydroclimate in the Pleistocene
JF  - Scientific reports
N2  - Understanding eastern African paleoclimate is critical for contextualizing early human evolution, adaptation, and dispersal, yet Pleistocene climate of this region and its governing mechanisms remain poorly understood due to the lack of long, orbitally-resolved, terrestrial paleoclimate records. Here we present leaf wax hydrogen isotope records of rainfall from paleolake sediment cores from key time windows that resolve long-term trends, variations, and high-latitude effects on tropical African precipitation. Eastern African rainfall was dominantly controlled by variations in low-latitude summer insolation during most of the early and middle Pleistocene, with little evidence that glacial-interglacial cycles impacted rainfall until the late Pleistocene. We observe the influence of high-latitude-driven climate processes emerging from the last interglacial (Marine Isotope Stage 5) to the present, an interval when glacial-interglacial cycles were strong and insolation forcing was weak. Our results demonstrate a variable response of eastern African rainfall to low-latitude insolation forcing and high-latitude-driven climate change, likely related to the relative strengths of these forcings through time and a threshold in monsoon sensitivity. We observe little difference in mean rainfall between the early, middle, and late Pleistocene, which suggests that orbitally-driven climate variations likely played a more significant role than gradual change in the relationship between early humans and their environment.
Y1  - 2022
U6  - https://doi.org/10.1038/s41598-022-06826-z
SN  - 2045-2322
VL  - 12
IS  - 1
PB  - Macmillan Publishers Limited
CY  - London
ER  - 
TY  - JOUR
A1  - Foerster, Verena
A1  - Asrat, Asfawossen
A1  - Ramsey, Christopher Bronk
A1  - Brown, Erik T.
A1  - Chapot, Melissa S.
A1  - Deino, Alan
A1  - Düsing, Walter
A1  - Grove, Matthew
A1  - Hahn, Annette
A1  - Junginger, Annett
A1  - Kaboth-Bahr, Stefanie
A1  - Lane, Christine S.
A1  - Opitz, Stephan
A1  - Noren, Anders
A1  - Roberts, Helen M.
A1  - Stockhecke, Mona
A1  - Tiedemann, Ralph
A1  - Vidal, Celine M.
A1  - Vogelsang, Ralf
A1  - Cohen, Andrew S.
A1  - Lamb, Henry F.
A1  - Schaebitz, Frank
A1  - Trauth, Martin H.
T1  - Pleistocene climate variability in eastern Africa influenced hominin evolution
JF  - Nature geoscience
N2  - Despite more than half a century of hominin fossil discoveries in eastern Africa, the regional environmental context of hominin evolution and dispersal is not well established due to the lack of continuous palaeoenvironmental records from one of the proven habitats of early human populations, particularly for the Pleistocene epoch. Here we present a 620,000-year environmental record from Chew Bahir, southern Ethiopia, which is proximal to key fossil sites. Our record documents the potential influence of different episodes of climatic variability on hominin biological and cultural transformation. The appearance of high anatomical diversity in hominin groups coincides with long-lasting and relatively stable humid conditions from similar to 620,000 to 275,000 years bp (episodes 1-6), interrupted by several abrupt and extreme hydroclimate perturbations. A pattern of pronounced climatic cyclicity transformed habitats during episodes 7-9 (similar to 275,000-60,000 years bp), a crucial phase encompassing the gradual transition from Acheulean to Middle Stone Age technologies, the emergence of Homo sapiens in eastern Africa and key human social and cultural innovations. Those accumulative innovations plus the alignment of humid pulses between northeastern Africa and the eastern Mediterranean during high-frequency climate oscillations of episodes 10-12 (similar to 60,000-10,000 years bp) could have facilitated the global dispersal of H. sapiens.
KW  - Evolutionary ecology
KW  - Limnology
KW  - Palaeoclimate
Y1  - 2022
U6  - https://doi.org/10.1038/s41561-022-01032-y
SN  - 1752-0894
SN  - 1752-0908
VL  - 15
IS  - 10
SP  - 805
EP  - 811
PB  - Nature Publ. Group
CY  - London
ER  -