Stable Isotope Analysis of Mammalian Enamel From the Early Pleistocene Site of Madigou, Nihewan Basin: Implications for Reconstructing Hominin Paleoenvironmental Adaptations in North China

The reconstruction of environmental and climatic changes in the Pleistocene is an essential contribution to our understanding of human evolutionary and behavioral adaptations. Well preserved fluvio-lacustrine sediments at Nihewan basin have yielded a rich record of Early Pleistocene Paleolithic sites and mammalian fossils which provide a unique opportunity for exploring hominin behavior and paleoecology in North China. Taxonomic studies of mammalian fossils have provided important clues to the general environmental setting and landscapes of Early Pleistocene humans in the fluvio-lacustrine basin of Nihewan, but little is known about their isotopic signatures. In this paper, mammal teeth species at the Madigou archaeological site (ca. 1.2 Ma) were selected for bulk and sequential enamel stable isotope (C, O) analysis. Results show a variety of ecological environments, including grassland and sparse forest landscapes, and distinct patterns across taxa. C3-C4 mixed vegetation predominated, but C4 vegetation was also relevant at times. Madigou early humans likely experienced cold/warm or dry/wet fluctuations in this northern China basin. We hypothesize that the environmental fluctuations and diversified landscapes may have driven flexibility in various aspects of early human technological behaviors, and allowed hominins to face the environmental challenges of northern latitudes after the initial expansion from Africa into East Asia at the onset of the Middle Pleistocene Climate Transition.

Luminescence dating of Youfangbei early late Pleistocene site, Nihewan Basin, North China

Sites dated to the early late Pleistocene are still limited in North China, which has hindered the detailed analysis of the development of Paleolithic industries in the late Pleistocene in this area. The Youfangbei (YFB) site is a newly excavated small-flake-tool Paleolithic site near the Youfang (YF) microblade site in the Nihewan Basin, North China. Because the small-flake-tool industry still existed in the late part of the late Pleistocene and might be related to the emergence of microlithic industries, the relationship between the two sites needs to be determined through a chronological study. Two profiles were excavated, and most of the artifact assemblages were unearthed in the lower profile (T1) from a depth of 0.9 m from the bottom. In this study, the feldspar post-infrared infrared stimulated luminescence method was applied to determine the age of the YFB site. Results showed that the upper profile was deposited from 86–0.5 ka, and the cultural layer in T1 yielded age of 124–82 ka, corresponding to Marine Isotope Stage (MIS) 5, with an irregular but generally mild climate. The age of the YFB site is too old to be directly related to that of the YF site, but it partly bridges a chronological gap of human occupation in the Nihewan Basin.

Early humans in East Asia: Insights into climatic influence on human evolution

<p>East Asia is a key area for probing into the interplay between Quaternary climate change and human adaptations to diverse terrestrial ecosystems. Integrated chronology based mainly on high-resolution magnetostratigraphy in conjunction with detailed biostratigraphy and high-precision isotopic dating of early humans and Paleolithic stone tools in mainland East Asia, western and southeastern Asia has provided insights into our understanding of climatic influence on human evolution in a variety of environments in the eastern Old World. For example, there is a prominent geographic expansion for early humans from low southern latitudes (e.g., tropical SE Asia and subtropical Yuanmou Basin and Bose Basin), through middle latitudes, to high northern latitudes (e.g., the Nihewan Basin). Especially, increased toolmaking skills and technological innovations are evident in temperate Nihewan Basin at the onset of the Mid-Pleistocene Climate Transition. The improved ability to adjust to diverse environments for early humans in East Asia has contributed to better understanding how climate change has shaped early human evolution.</p>

Atlantic meridional overturning circulation modulation of late Pleistocene to middle Holocene Asian summer monsoon variability and palaeoanthropological implications

Asia contains more than half the world’s population, and their lives are significantly related to summer monsoon moisture supply. Here, we investigate features and dynamics of late Pleistocene–middle Holocene Asian summer monsoon variability in the Nihewan Basin, North China, which was a critical home for early humans in East Asia throughout the Quaternary. We present new mineral magnetic records between ∼16 and 6 ka from the Yujiagou archeological site in the northern Nihewan Basin, which contains >40 000 stone tools, 2 pottery pieces and 19 686 mammal fossils. Magnetic properties of the Yujiagou section are dominated by pedogenic fine-grained magnetite/maghemite concentration, which ranges from superparamagnetic/single domain up to fine pseudo-single domain sizes. We use multiple environmental magnetic proxies, which measure pedogenic magnetite/maghemite concentration, to document that summer monsoon precipitation was low before ∼14.5 ka and high during the Bölling–Allerød warm period (14.5–12.8 ka), and shifted to low values at the onset of the Young Dryas cold period ∼12.4 ka, followed by a sustained long-term increasing trend from 12.4 to 6 ka. We relate these monsoon precipitation changes to the consistent Atlantic Meridional Overturning Circulation variability, which modulated North Hemisphere temperatures and displacements of Inter-Tropical Convergence Zone and Walker circulation over the Pacific Ocean. The observed large-amplitude deglacial Asian monsoon changes may have played a role in several key evolutionary changes in Asia implicated by the Yujiagou archeological evidence, including Paleolithic to Neolithic culture transition, Asian pottery development, and early human dispersals from Asia to America.

Reconstructing vegetation and climate in the Nihewan Basin, North China, during the middle Pleistocene (~603-587 ka) to trace the evolution of human environments

Aims The Nihewan Basin of North China, considered the cradle of Eastern civilisation, contains a set of late Cenozoic strata and artefacts used by Homo erectus in the early Pleistocene (~1.66 Ma -780 ka) and the cranial bones and teeth of early H. sapiens from the late middle Pleistocene (~370-260 ka). Palynological studies provide an opportunity to explore the living environment of early humans. Methods Palynological samples from the Hutouliang Section (~603-587 ka) of the Xiaodukou Formation of the Nihewan Basin were treated by heavy liquid flotation. Based on the palynological assemblages from the section, vegetation and climate in the Nihewan Basin were reconstructed. Important Findings The dynamic vegetation changed from temperate needle- and broad-leaved mixed forest-steppe (mainly Picea, Abies, Betula, Juglans, Artemisia and Chenopodiaceae) to conifer forest (mainly Pinus, Picea and Abies), which saw the replacement of H. erectus by early H. sapiens. The comparison of the Nihewan Basin with other human sites around the world during the same period reveals that early humans preferred to live in caves, accompanied by relatively open steppe or forest-steppe environments, inhabited by numerous mammals. Therefore, it is inferred that the emergence of dense conifer forest and the disappearance of open steppe environments in the Nihewan Basin at approximately 603-587 ka provide new evidence that early humans followed most mammals to steppe or forest-steppe environments and thus left the Nihewan Basin. These new findings not only enrich our knowledge of early human behaviour, such as their diet, migration and settlement, but also fill in gaps in paleovegetation and paleoenvironmental research in the Nihewan Basin during the middle Pleistocene (780-400 ka).