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The Luo River is located in the southern part of the Chinese Loess Plateau and the northern part of the Weihe Basin, in Central China. In the basin it flows proximal to the site of the Luyang Wetland core, which is an important archive of climate change over the past 1 Myr in this region. In this paper, the contribution of the Luo River to the sedimentary record is analyzed by reconstructing the evolution of this river during the Middle to Late Pleistocene. It is argued that an alluvial fan of the Luo River has contributed to the sedimentary archive until approximately 200–240 ka. From this moment onwards, the fan became incised and terraces began to form. The formation of a new alluvial fan further downstream led to the disconnection of the Luo River from the Luyang Wetland core site. We propose that this series of events was caused by the displacement of an intra-basinal fault and the resultant faulting-forced folding, which caused increased relative subsidence, and thus increased sedimentation rates at the core site. Therefore, a complete sediment record in the ‘Luyang Wetland’ was preserved, despite the disconnection from the Luo River. The chronology of the fans and terraces was established using existing age control (U-series, ESR, OSL, pIRIR 290 and magnetic susceptibility correlation), and through correlation of the loess-paleosol cover to marine isotope stages. Based on sedimentological characteristics of the fluvial sequence, we suggest that incision of the Luo River occurred in two steps. Small incisions took place at transitions to interglacials and the main incision phases occur at the transition from an interglacial to glacial climate. Due to the incision, basal parts of the oldest Luo River alluvial fan are exposed, and it is in one of these exposures that the famous Dali Man skull was retrieved. This study shows that the Dali Man did not live on a river terrace as previously thought, but on an aggrading alluvial fan, during wet, glacial conditions. [ABSTRACT FROM AUTHOR]

This paper reports the discovery of a new mammalian assemblage at Mocun cave in 2000 by the Natural History Museum of Guangxi. The Mocun site is located in a residual karst peak in southwest Guangxi, south China. Abundant mammalian fossil teeth and bones were extracted from relatively thick deposits, well constrained stratigraphically. The results show that 1) the Mocun fauna is composed of typical species of the " Ailuropoda - Stegodon association", including Stegodon, Ailuropoda, Rhinoceros, Pongo, Tapiru s, Megatapirus, and Elephas, common in the Middle to the Late Pleistocene, with a larger portion of modern species; 2) By employing U-series dating (MC-ICP-MS) method on both the soda straw stalactites and mammalian teeth collected from deposits, the age of the Mocun fauna has been constrained between 66 and 101 ka, a transitional period from the interglacial stage MIS5 to the beginning of the last glacial stage (MIS4), representing one of the securely dated Late Pleistocene sites in southern China so far; 3) The composition in large mammals suggests a forested environment which harboured a great biodiversity in large species; 4) The taphonomic analysis indicates that the fossil accumulation is mainly due to activities of porcupines and to water flows; 5) Interestingly, our taxonomic study reveals some changes in the occurrence of Tapirus sinensis and Megatapirus augustus between ∼66 and ∼86 Ka, along with a change in the abundance of artiodactyls versus primates. It remains to demonstrate with more comprehensive records if these changes may be related to the mid-Late Pleistocene climatic transition. • a new mammalian fauna cave site (Mocun cave) with accurate date to 66 and 101 ka in southwest Guangxi. • The composition in large mammals suggests a compatible habitat for a great biodiversity of species. • Some changes between layers with Tapirus sinensis replaced by Megatapirus augustus between ∼66 and ∼86 Ka, along with a change in the abundance of artiodactyls versus primates. [ABSTRACT FROM AUTHOR]