Late Pleistocene climate drivers of early human migration

Nature ◽  
2016 ◽  
Vol 538 (7623) ◽  
pp. 92-95 ◽  
Author(s):  
Axel Timmermann ◽  
Tobias Friedrich
2004 ◽  
Vol 62 (1) ◽  
pp. 105-109 ◽  
Author(s):  
Carolyn L. Ramsey ◽  
Paul A. Griffiths ◽  
Daryl W. Fedje ◽  
Rebecca J. Wigen ◽  
Quentin Mackie

Recent investigations of a limestone solution cave on the Queen Charlotte Islands (Haida Gwaii) have yielded skeletal remains of fauna including late Pleistocene and early Holocene bears, one specimen of which dates to ca. 14,400 14C yr B.P. This new fossil evidence sheds light on early postglacial environmental conditions in this archipelago, with implications for the timing of early human migration into the Americas.


2021 ◽  
Vol 9 ◽  
Author(s):  
Amin Ghafarpour ◽  
Farhad Khormali ◽  
Xianqiang Meng ◽  
Hossein Tazikeh ◽  
Thomas Stevens

Paleoclimatic investigation of loess-paleosol sequences from northern Iran is important for understanding past changes in a region highly sensitive to shifts in precipitation, and along potential routes of past human migration. Here, we present carbon and oxygen isotopic compositions of bulk carbonate (δ13Cbc and δ18Obc, respectively) coupled with particle size distributions of samples from the Mobarakabad section, northern Iran, to study past wind dynamics and hydroclimate. We also present new initial clay-sized Hf-Nd isotope results from key horizons in order to assess general dust sources. Variations of δ13Cbc and δ18Obc values of modern soils compared to paleosols allow reconstruction of late Pleistocene–Holocene climate change in the area. Our results show severe drought during a major eolian deposition phase (EDP) after 34 ka. The thickness and PSD of the C horizon of unit 5 suggest significant shifts in loess sources and depositional environments during this EDP after 34 ka. Indeed, based on our new clay-sized Hf-Nd data, we hypothesize that the loess unit 5 might originate from the young crustal source of the Alborz and Kopet Dagh mountains. In general, the PSD of C horizons in the section is bimodal in the silt fraction and the very small, very fine clay fraction, with a mode at c. 1 μm in the modern soil and paleosols possibly produced by weathering and pedogenic processes. There also appears to be a good correlation between δ13Cbc and δ18Obc values, differentiating phases of loess accumulation and paleosol formation and hence providing quantitative data for reconstructing paleoclimatic conditions in the study area.


2021 ◽  
Vol 267 ◽  
pp. 107109
Author(s):  
Zaibao Yang ◽  
Yanli Lei ◽  
Yair Rosenthal ◽  
Tiegang Li ◽  
Zhimin Jian

Nature ◽  
2021 ◽  
Vol 592 (7853) ◽  
pp. 253-257 ◽  
Author(s):  
Mateja Hajdinjak ◽  
Fabrizio Mafessoni ◽  
Laurits Skov ◽  
Benjamin Vernot ◽  
Alexander Hübner ◽  
...  

AbstractModern humans appeared in Europe by at least 45,000 years ago1–5, but the extent of their interactions with Neanderthals, who disappeared by about 40,000 years ago6, and their relationship to the broader expansion of modern humans outside Africa are poorly understood. Here we present genome-wide data from three individuals dated to between 45,930 and 42,580 years ago from Bacho Kiro Cave, Bulgaria1,2. They are the earliest Late Pleistocene modern humans known to have been recovered in Europe so far, and were found in association with an Initial Upper Palaeolithic artefact assemblage. Unlike two previously studied individuals of similar ages from Romania7 and Siberia8 who did not contribute detectably to later populations, these individuals are more closely related to present-day and ancient populations in East Asia and the Americas than to later west Eurasian populations. This indicates that they belonged to a modern human migration into Europe that was not previously known from the genetic record, and provides evidence that there was at least some continuity between the earliest modern humans in Europe and later people in Eurasia. Moreover, we find that all three individuals had Neanderthal ancestors a few generations back in their family history, confirming that the first European modern humans mixed with Neanderthals and suggesting that such mixing could have been common.


2021 ◽  
Author(s):  
Nicholas Golledge

<p>During the Pleistocene (approximately 2.6 Ma to present) glacial to interglacial climate variability evolved from dominantly 40 kyr cyclicity (Early Pleistocene) to 100 kyr cyclicity (Late Pleistocene to present). Three aspects of this period remain poorly understood: Why did the dominant frequency of climate oscillation change, given that no major changes in orbital forcing occurred? Why are the longer glacial cycles of the Late Pleistocene characterised by a more asymmetric form with abrupt terminations? And how can the Late Pleistocene climate be controlled by 100 kyr cyclicity when astronomical forcings of this frequency are so much weaker than those operating on shorter periods? Here we show that the decreasing frequency and increasing asymmetry that characterise Late Pleistocene ice age cycles both emerge naturally in dynamical systems in response to increasing system complexity, with collapse events (terminations) occuring only once a critical state has been reached. Using insights from network theory we propose that evolution to a state of criticality involves progressive coupling between climate system 'nodes', which ultimately allows any component of the climate system to trigger a globally synchronous termination. We propose that the climate state is synchronised at the 100 kyr frequency, rather than at shorter periods, because eccentricity-driven insolation variability controls mean temperature change globally, whereas shorter-period astronomical forcings only affect the spatial pattern of thermal forcing and thus do not favour global synchronisation. This dynamical systems framework extends and complements existing theories by accomodating the differing mechanistic interpretations of previous studies without conflict.</p>


2009 ◽  
Vol 197 (1-2) ◽  
pp. 27-34 ◽  
Author(s):  
Pavel M. Dolukhanov ◽  
Sergei V. Kadurin ◽  
Evgeny P. Larchenkov

2016 ◽  
Vol 56 (2-3) ◽  
pp. 109-122 ◽  
Author(s):  
Cornelia Barth ◽  
Douglas P. Boyle ◽  
Benjamin J. Hatchett ◽  
Scott D. Bassett ◽  
Christopher B. Garner ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document