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Gigantopithecus was a giant ape once lived in Southeast Asia and China during the Pleistocene period. Longgupo and Jianshi Longgudong sites in West-Hubei and Three Gorges region in South China are the northernmost evidences of Gigantopithecus presence in the world up to date. To obtain the detailed chronology of these two sites, paleomagnetic and radiometric dating methods were attempted, including cosmogenic burial dating of the sediment. However, the efforts failed because of the scarce of quartz minerals in the sediment. Combined electron spin resonance and uranium series (ESR/U-series) method which could date the fossil teeth directly with the age range from Early to Late Pleistocene was also applied and the results obtained at Longgupo site already published. Here, we report the first radiometric dating results for teeth carried out from Jianshi Longgudong Western Branch cave which is renowned for the discovery of both Gigantopithecus fossils and undoubted stone artifacts. The main challenge of dating Jianshi Longgudong site is the reconstruction of external dose rate of the fossil samples where their provenance sections were not preserved. The mean radioelement concentrations in the sediments measured in the laboratory with different water content estimation were initially used to calculate the ESR/U-series ages. Our ESR/U-series dating of two mammalian fossil teeth from the lower layer 8 gives a weight mean age of 1512 ± 94 ka, while a mean age of 1044 ± 53 ka was obtained for two teeth from the upper layer 4. These ages support one of the previous paleomagnetic dating interpretation which propose that the hominin fossil layer in Jianshi site was not older than 1.78 Ma, i.e. that the upper boundary of the Olduvai subchron, and are in agreement with the faunal evidence which suggest that Jianshi site is younger than the adjacent Longgupo site dated also by combined ESR/U-series and paleomagnetic methods to 2.0-2.5 Ma. Further study of the site including the radiometric dating study of the fossil layers preserved in the Eastern Branch cave may help to achieve a definitive conclusion of the chronology of Gigantopithecus settlement in Jianshi Longgudong site. [ABSTRACT FROM AUTHOR]

One of the most important Paleolithic archaeological sites in East Asia, the Xujiayao locality in the Nihewan Basin, North China, has yielded twenty Homo fossils as well as tens of thousands of artifacts and mammalian fossils. The Xujiayao hominin possibly represents a new Homo lineage, since it exhibits specific evolutionary characteristics of Neanderthals, modern H. sapiens, and Denisovans, which permits a deeper understanding of the diversification of the genus Homo and the origin of H. sapiens. However, the evolutionary history of the Xujiayao Homo is still unclear, due partially to controversial associated chronometric dates. We carried out detailed OSL dating measurements using a post-IR IRSL SAR protocol involving two experimental conditions with different preheating and stimulation temperatures on coarse-grained K-feldspar on 14 samples from Xujiayao. The first experimental condition included a preheat temperature of 320°C for 60 s to natural/regenerative/test dose measurements, and stimulation with IR LEDs at 290°C for 200 s following IR stimulation at 200°C for 200 s, while the second protocol included IRSL stimulation, first at 50°C and then at 225°C. Our results show that the sensitivity change of the natural/regenerative pIRIR 290°C and pIRIR 225°C signals from the coarse-grained K-feldspar of all samples could be corrected by the test dose, and both the pIRIR 290 and pIRIR 225 signals could be recovered with the ratio of recovered dose to the given dose of over 0.9, indicating both protocols are suitable for reproducible De determination. After correction for anomalous fading, the pIRIR 225 protocol yielded an age range comparable to that of the pIRIR 290 protocol, ranging from 182-108 ka. Subsequently, Bayesian analyses were conducted on these and previously published OSL data, suggesting that the upper and lower cultural layers of the Xujiayao site fall within a range from 141±13 ka to 126±35 ka and from 172±22 ka to 166±16 ka, both corresponding to the cold and dry Penultimate Glacial Period (MIS 6), and agreeing well with conclusions drawn from palynological and mammalian faunal analyses conducted at Xujiayao, but slightly younger than the 26Al/10Be burial dating results from the lower cultural layer of 240±50 ka. Thus, our OSL results provide independent age constraints of 172±22 ka-126±35 ka for the presence of hominins at Xujiayao. Considering the great morphological similarity between the Xujiayao and Xuchang (or Lingjing, Henan) fossil crania, we conclude the age of the Xujiayao hominin remains to be 141-126 ka, during the cold and dry Penultimate Glacial Period. During this phase, diverse representatives of archaic Homo, including the Baishiya, Gansu Denisovan, H. longi (also known as the Harbin Dragon Man), and the Xuchang hominin, coexisted with H. sapiens from Zhiren Cave in Guangxi, South China, possibly indicating significant heterogeneity existed among hominins in East Asia during MIS 6. The comparatively inhabitable monsoonal environment of East Asia and the region's relative geographical isolation from Europe may have played important roles in shaping the diversity of hominin lineages emergent in this region. [ABSTRACT FROM AUTHOR]

Our understanding of early human dispersals in Europe is based on a handful of archaeological sites spread across the southern margin of the continent. Among them, Pirro Nord-13 (Italy) is usually considered to document the oldest evidence of human presence in Western Europe, although the site itself has never been numerically dated. Instead, the age of the Mode 1 (=Oldowan) lithic assemblage and associated fossils found in this karst fissure has been inferred from biochronology and estimated to be 1.3-1.6 Ma [1]; making it older than the Spanish Mode 1 pre-Jaramillo localities of Atapuerca Sima del Elefante, Barranco León and Fuente Nueva-3, which have been dated by a combination of numerical methods and palaeomagnetism. We provide here the results from the first dating study of the site involving a wide range of methods: Electron Spin Resonance (ESR) and single grain thermally-transferred optically stimulated luminescence (SG TT-OSL) dating of quartz grains, combined U-series/ESR dating of fossil teeth and palaeomagnetic analyses of sediment. Such a multi-technique dating approach offers the possibility to obtain chronological constraints for both the fossil assemblage and the host sediment. The (semi-)independent methods consistently yield an Early Pleistocene age for the site, although the resulting estimates are much younger than initially inferred from biochronology. We discuss potential reliability considerations with the new numerical ages and existing biochronological inference. Nevertheless, these results suggest either a complex taphonomic history in which fossil remains, lithic artifact and host sediment might not be coeval, or at least the sediment was most recently exposed to sunlight during the latest part of the Early Pleistocene. [ABSTRACT FROM AUTHOR]