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Gigantopithecus was a great ape once lived in Southeast Asia and China during the Pleistocene, and the northernmost evidence of its presence is presently known from the Longgupo and Jianshi Longgudong sites located in the West-Hubei and Three Gorges region in Southof China. Here, we report the first radiometric dating by ESR/U-series method on mammalian teeth of Jianshi Longgudong site which was found in 1970s, and renowned by the discovery of both possible hominin and Gigantopithecus fossils in association with undoubted stone artifacts. As the cave site was completely emptied by the successive excavations, the analyzed teeth were selected from museum collections while the dosimetry was established from reworked sediments sampled on the site. The results obtained on two fossil teeth from the lower layer 8 give a weighted mean age of 1512 ± 94 ka, while a mean age of 1044 ± 53 ka was obtained for two other teeth from the upper layer 4. These ESR/U-series dating results, in agreement with the fauna record, are younger than the previous paleomagnetic dating interpretation and suggest that Jianshi Longgudong sequence is younger than the Olduvai subchron and the neighboring Longgupo site dated by the same methods to ca 2.2–2.5 Ma. • Northernmost evidence of the Gigantopithecus is dated by radiometric dating method. • The misinterpretation of the paleomagnetic results of Longgudong site is corrected. • Dating results indicate Gigantopithecus survival with hominin during Pleistocene. [ABSTRACT FROM AUTHOR]

Coupled ESR and U-series analyses of mammalian fossil teeth were carried out on two localities of Yiyuan hominin site (Locality 1 and 3) in northern China. The U-migration history of the fossil samples could be reconstructed by the combination of the two techniques, and overcome the limitation of stand-alone ESR and U-series age estimation. We obtained a combined ESR/U-series age (AU model) range from ∼420 to 320 ka from nine teeth recovered from the two localities, which pinpoints the deposition of hominin layer of Yiyuan site to MIS 11 to 9. The age results in this study places Yiyuan site at the same time range of Zhoukoudian Locality 1 and Hexian Homo erectus sites. Comparing with other hominin sites, this study of Yiyuan Homo erectus site highlights the possibility of coexistence between Homo erectus and archaic H. sapiens in China. [ABSTRACT FROM AUTHOR]

This study presents palaeodosimetric results from the Middle Pleistocene archaeological site of Coudoulous I (Lot, SW France). Nine sedimentary quartz samples (41–60 μm) have been analyzed using a multiple aliquot protocol based on the measurement of the TT-OSL signal. In addition, 7 teeth and 7 bones have been dated by combining the ESR method with U-series analyses. Both methods gave consistent age results allowing correlation of the Early Middle Paleolithic Human occupation of the site to MIS 6 and part of the Lower Paleolithic tools to MIS 7. Beyond the establishment of a radiometric chronology for the Coudoulous I sequence, this study focuses on the information extracted from the intercomparison of the methods. Our data suggest that 1) the TT-OSL signal is stable over at least the last 230 ka (considering the age range of the studied samples), 2) there are not significant problems of incomplete bleaching leading support to the applicability of the TT-OSL technique for sedimentary deposits associated with karstic contexts. This approach highlights the interest of combining luminescence and ESR/U-series methods to discuss the reliability of the dating results. [ABSTRACT FROM AUTHOR]

Abstract: Combined ESR/U-series dating of tooth enamel using US model implies the calculation of a specific parameter p for each dental tissue to reconstruct its U-uptake history. The US model simulates this history as a continuous incorporation process without leaching, where the 238U–234U–230Th system evolves towards secular equilibrium state. Consequently, the application of this model is restricted to the samples displaying 230Th/234U activity ratio below or close to equilibrium with maximum value of ∼1.05 for each tissue. In order to overcome this limitation, here, a new model named Accelerating Uptake (AU) model is proposed. This model describes U-uptake into dental tissue as an accelerating process by the introduction of two parameters, the initial uptake rate and the acceleration of this uptake rate. The AU model is then able to reconstruct a process combining incorporation followed by leaching, as well as continuous uptake one. With this model, the evolution of 230Th/234U activity ratio with time can reach values higher than unity, even beyond equilibrium. The AU model is useful in cases for which age estimates cannot be calculated by routine use of US model. The application of the AU model to the palaeoanthropological site of Mauer in Germany shows its potential for extending the applicability of the combined ESR/U-series dating of tooth enamel. [Copyright &y& Elsevier]

Abstract: The Dali skull is a key fossil for understanding human evolution in China. It has been attributed either to an archaic Homo sapiens, an evolved Homo erectus or to other species of Homo, such as Homo heidelbergensis. The cranium was discovered in 1978 in Shaanxi Province in a fluvial terrace which was recovered by a loessic sequence including two interglacial palaeosoils. ESR/U-series data analyses were carried out on several teeth recovered from the palaeoanthropological level. Four samples exhibit different kinds of uranium-uptake behaviour, but the results seem to indicate that the cranium is coeval with Marine Isotope Stage (MIS) 8 and that some teeth might be reworked from older deposits. [ABSTRACT FROM AUTHOR]

Previous studies have suggested that the Lower-to-Middle Paleolithic transition was associated with the earliest Neanderthals, but recent research has established that the oldest Neanderthal fossils and the first signs of their technologies and behavior appear from MIS 11 or possibly earlier. To understand these changes, re-evaluation of the evidence is necessary to determine if this transition corresponds to a progressive evolution rather than abrupt change. Orgnac 3 is a key and appropriate site to study this research context. Located in southern France, it yields a long stratigraphic sequence testifying the evolution of technical and subsistence behaviors of pre-Neanderthal human groups during a Middle Pleistocene interglacial-glacial cycle. In this article, a new chronological framework is provided for the sequence based on results of dating methods applied to various types of geological materials. Speleothems and volcanic minerals, dated in previous studies by U-series and 40Ar/39Ar, respectively, show periods of calcitic crystallization and regional volcanic activity. Other materials, such as heated flints and herbivore teeth, are directly related to evidence of anthropogenic activities and are analyzed in the present work by trapped-charge dating methods such as thermoluminescence and electron spin resonance combined with uranium series (ESR/U-series). The new thermoluminescence and ESR/U-series dates confirm the attribution of the Orgnac 3 stratigraphic sequence to the MIS 10–MIS 8 period and are discussed in relation to paleoenvironmental data derived from bioarchaeological studies. The paleoanthropological levels, including the emergence of Levallois technology, are dated to ca. 275 ka (early MIS 8) and appear coeval to a wet and temperate period recorded locally, the Amargiers interstadial, defined in the regional palynological records. The implications of this reassessed chronology for the archaeological assemblages are discussed in the wider context of behavioral innovations from MIS 11 onward and their establishment in subsequent periods. [ABSTRACT FROM AUTHOR]

The stratigraphic sequences of numerous Palaeolithic sites of Central and Southern Italy, very rich in both archaeological and palaeontological remains, have also recorded Pleistocene volcanic events through volcanic ash deposits (tephra). They allow the establishment of an accurate chronological framework by comparing results obtained by 40Ar/39Ar dating method on single volcanic K-feldspar crystals, with those derived from ESR and ESR/U-series analyses on fluvial bleached quartz and tooth enamel respectively. Since 2009, these three methods were hence applied on samples of several Middle Pleistocene sites of Central and Southern Italy including both volcanic and archaeological levels (from the west to the east): La Polledrara di Cecanibbio, Isoletta, (Latium), Guado San Nicola, Isernia La Pineta (Molise), Valle Giumentina (Abruzzo) and Venosa Notarchirico (Basilicata). The obtained results, covering a time range from 660 to 350 ka, prove that such a multi-method approach when possible is essential to constrain the chronology of each site and allow the recognition of the specific limitations due to the lack of quartz for ESR or to complex geochemical histories in teeth rendering difficult the ESR/U-series method. Despite these limitations, the ESR framework is globally in agreement with the 40Ar/39Ar chronology, while ESR/U-series dates can be underestimated for the oldest sites. In such cases, an isochron approach attests however of the quite good reliability of the palaeodosimetric reconstruction and the observed age underestimation could be related to other factors affecting the ESR age determination. [ABSTRACT FROM AUTHOR]