Altered cropping pattern and cultural continuation with declined prosperity following abrupt and extreme arid event at ~4,200 yrs BP: Evidence from an Indus archaeological site Khirsara, Gujarat, western India

The Spatiotemporal Patterns of Human Settlement during the Longshan and Erlitou Periods in Relation to Extreme Floods and Subsistence Strategy in the Upper and Middle Qin River Reaches, Central China

Human settlement numbers have significantly changed before and after ~4000 cal. y BP in the upper and middle Qin River reaches, but the external and internal factors driving this change remain unclear. In this study, we examine changing spatial and temporal patterns of the Longshan and Erlitou settlements in relation to extreme flooding at ~4000 cal. y BP and a variety of subsistence strategies during the Longshan and Erlitou periods. The results indicate that settlement number, settlement distribution, and subsistence strategies exhibited obvious shifts between the Longshan and Erlitou periods, and the episode at ~4000 cal. y BP was an extreme-flood-rich interval within and around the Qin River Basin. During the Longshan and Erlitou periods, millet-based agriculture dominated local subsistence strategy, and ancient people would prefer to reside in the areas suitable for farming, causing the valley plains in the upper and middle Qin River reaches to contain most Longshan and Erlitou settlements. However, the frequent occurrence of extreme floods at ~4000 cal. y BP, in conjunction with intergroup conflicts due to a large amount of population immigration during the late Longshan period, is likely to have jointly decreased the settlement number and shrunk the spatial range of human settlement distribution. Subsequently, with the end of the extreme-flood-rich episode and the increasing proportion of higher-water-requirement foxtail millet in cropping structures of human subsistence strategy, more Erlitou settlements were distributed in the wetter valley plains of the middle Qin River reaches.

The "2.8 ka BP Cold Event" Indirectly Influenced the Agricultural Exploitation During the Late Zhou Dynasty in the Coastal Areas of the Jianghuai Region

As a global cooling event, many of the climatic and socio-cultural mechanisms that resulted in changes after the 2. 8 ka BP event remain unclear. In China, this period roughly corresponds with the Zhou Dynasty (1046-212 BC), a critical period when ancient Chinese civilization was experiencing significant cultural and technological changes, including the movement of people to modern-day Jiangsu Province, where they intensively used the natural resources found in this the coastal area. Recent archaeobotanical evidence, and two radiocarbon dates on wheat and foxtail millet, indicate that the Datongpu site, which dates around 2,600 cal a BP, was occupied during this period of transition around the 2.8 ka BP climate event. In total, our investigations recovered 3,399 carbonized seeds from seventy-four flotation samples, of which rice, foxtail millet, broomcorn millet, and wheat seeds where predominant along with 2,296 weed seeds. Additionally, we identified several rice spikelets and wheat rachises. The high number of carbonized rice grains indicates that rice farming was the primary crop in an otherwise mixed rice-dry farming system at Datongpu. In addition, we argue that the "2.8 ka BP cold event" probably influenced population growth and caused food shortages throughout Central China, leading people to migrate southeastward along the Huai River to the coastal areas of Jianghuai Region. We argue that this abrupt shift in the climate indirectly facilitated the exploitation and emergence of large-scale agriculture in this area. Our study provides an example for the indirect impact of climate change in areas with relatively favorable climate conditions.

Integrating Lipid and Starch Grain Analyses From Pottery Vessels to Explore Prehistoric Foodways in Northern Gujarat, India

This study attempts a holistic approach to past foodways in prehistoric northern Gujarat, India, by considering evidence of food production, distribution, preparation and consumption. We present here the results of a pilot residue study, integrating lipid and starch grain analyses, conducted on 28 ceramic vessels from three Chalcolithic/Harappan settlements (c. 3300–2000 cal. BC) in northern Gujarat, which are discussed in the light of previous evidence of plant and animal acquisition and preparation strategies in this region. We aim to explore how the prehistoric inhabitants of northern Gujarat transformed ingredients into meals, focusing on how different foodstuffs were processed. When assessed on their own, the lipid and compound-specific isotopic data suggest that animal fats were primarily processed in ceramic vessels, specifically non-ruminant fats. However, lipid residue analysis favors the detection of fat-rich animal products and is often unable to disentangle signatures resulting from the mixing of plant and animal products. The incorporation of starch grain analyses provides evidence for the processing of a range of plants in the vessels, such as cereals, pulses and underground storage organs. Together, the results provide a holistic perspective on foodways and a way forward in overcoming preservational and interpretational limitations.

Sex-Biased Population Admixture Mediated Subsistence Strategy Transition of Heishuiguo People in Han Dynasty Hexi Corridor

The Hexi Corridor was an important arena for culture exchange and human migration between ancient China and Central and Western Asia. During the Han Dynasty (202 BCE–220 CE), subsistence strategy along the corridor shifted from pastoralism to a mixed pastoralist-agriculturalist economy. Yet the drivers of this transition remain poorly understood. In this study, we analyze the Y-chromosome and mtDNA of 31 Han Dynasty individuals from the Heishuiguo site, located in the center of the Hexi Corridor. A high-resolution analysis of 485 Y-SNPs and mitogenomes was performed, with the Heishuiguo population classified into Early Han and Late Han groups. It is revealed that (1) when dissecting genetic lineages, the Yellow River Basin origin haplogroups (i.e., Oα-M117, Oβ-F46, Oγ-IMS-JST002611, and O2-P164+, M134-) reached relatively high frequencies for the paternal gene pools, while haplogroups of north East Asian origin (e.g., D4 and D5) dominated on the maternal side; (2) in interpopulation comparison using PCA and Fst heatmap, the Heishuiguo population shifted from Southern-Northern Han cline to Northern-Northwestern Han/Hui cline with time, indicating genetic admixture between Yellow River immigrants and natives. By comparison, in maternal mtDNA views, the Heishuiguo population was closely clustered with certain Mongolic-speaking and Northwestern Han populations and exhibited genetic continuity through the Han Dynasty, which suggests that Heishuiguo females originated from local or neighboring regions. Therefore, a sex-biased admixture pattern is observed in the Heishuiguo population. Additionally, genetic contour maps also reveal the same male-dominated migration from the East to Hexi Corridor during the Han Dynasty. This is also consistent with historical records, especially excavated bamboo slips. Combining historical records, archeological findings, stable isotope analysis, and paleoenvironmental studies, our uniparental genetic investigation on the Heishuiguo population reveals how male-dominated migration accompanied with lifestyle adjustments brought by these eastern groups may be the main factor affecting the subsistence strategy transition along the Han Dynasty Hexi Corridor.

Compound specific isotope analysis of lipid residues provides the earliest direct evidence of dairy product processing in South Asia

The early evidence of domesticated animals and human–animal interaction in South Asia can be traced back to the seventh millennium BCE; however, our understanding of their use is incomplete and limited to the analysis of animal bones from archaeological sites. By the third millennium BCE with the emergence of the Indus Civilization, cattle and water-buffalo became the primary domesticates and outnumbered any other animals at the majority of the Indus settlements. Based on the analysis of skeletal remains and ethnographic data, a number of studies have suggested that cattle and water-buffalo were utilized for their meat, dairy, hides, and other labor-oriented jobs. While some of these claims are backed by empirical data, others are primarily discussed as hypotheses, for example, the exploitation of dairy. In this paper, by analyzing the absorbed lipid residues from fifty-nine ceramic sherds recovered from an agro-pastoral settlement that was occupied during the peak of the Indus period around mid- to late third millennium BCE, we provide the earliest direct evidence of dairy product processing, particularly from cattle and possibly from some water-buffalo. By providing direct evidence of animal product processing, we identify the use of primary domesticated animals and other resources in the diet during the Indus Civilization.

Intensified summer monsoon and the urbanization of Indus Civilization in northwest India

Today the desert margins of northwest India are dry and unable to support large populations, but were densely occupied by the populations of the Indus Civilization during the middle to late Holocene. The hydroclimatic conditions under which Indus urbanization took place, which was marked by a period of expanded settlement into the Thar Desert margins, remains poorly understood. We measured the isotopic values (δ¹⁸O and δD) of gypsum hydration water in paleolake Karsandi sediments in northern Rajasthan to infer past changes in lake hydrology, which is sensitive to changing amounts of precipitation and evaporation. Our record reveals that relatively wet conditions prevailed at the northern edge of Rajasthan from ~5.1 ± 0.2 ka BP, during the beginning of the agricultural-based Early Harappan phase of the Indus Civilization. Monsoon rainfall intensified further between 5.0 and 4.4 ka BP, during the period when Indus urban centres developed in the western Thar Desert margin and on the plains of Haryana to its north. Drier conditions set in sometime after 4.4 ka BP, and by ~3.9 ka BP an eastward shift of populations had occurred. Our findings provide evidence that climate change was associated with both the expansion and contraction of Indus urbanism along the desert margin in northwest India.