Critical role of climate change in plant selection and millet domestication in North China

Abstract

While North China is one of the earliest independent centers for cereal domestication in the world, the earliest stages of the long process of agricultural origins remain unclear. While only millets were eventually domesticated in early sedentary societies there, recent archaeobotanical evidence reported here indicates that grasses from the Paniceae (including millets) and Triticeae tribes were exploited together by foraging groups from the Last Glacial Maximum to the mid-Holocene. Here we explore how and why millets were selected for domestication while Triticeae were abandoned. We document the different exploitation and cultivation trajectories of the two tribes employing ancient starch data derived from nine archaeological sites dating from 25,000 to 5500 cal BP (LGM through mid-Holocene) in North China. With this diachronic overview, we can place the trajectories into the context of paleoclimatic reconstructions for this period. Entering the Holocene, climatic changes increased the yield stability, abundance, and availability of the wild progenitors of millets, with growing conditions increasingly favoring millets while becoming more unfavorable for grasses of the Triticeae tribe. We thus hypothesize that climate change played a critical role in the selection of millet species for domestication in North China, with early domestication evidenced by 8700 cal BP.

Agriculture, the Environment, and Social Complexity From the Early to Late Yangshao Periods (5000–3000 BC): Insights From Macro-Botanical Remains in North-Central China

“…Climate change played a critical role in the selection of millet species for domestication during different periods in North China (Lu, 2017;Yang et al, 2018). However, geological records, including eolian deposits, lake sediments and soils, have shown that during the Yangshao Warm Period climatic conditions in Henan Province were much more favorable for cultivation than those seen today (Shakun et al, 2012;Marcott et al, 2013;Chen et al, 2015;Figures 4A,B).…”

“…Additionally, factors constraining or facilitating the development of the agricultural practices associated with these social transformations are complex, which have been proposed by scholars as climatic changes (Dong et al, 2012;Yang et al, 2018), social complexification (Wang J. H., 2005;Gao, 2009;Zhong et al, 2020), or developments in agricultural technology (Fan, 1988;Gao, 2009;Zhao, 2018). Climate change is supposed to have a greater impact on agriculture at large spatial scales, but geomorphologic condition will be more influential at smaller, more local scales (Robert et al, 1989).…”

“…Studies in the Near East, for example, have shown that agriculture originates from marginal piedmont grasslands and transfers to valleys and lowlands (Binford, 1968;Flannery, 1973); Liu et al (2009) and Ren et al (2016) provided evidence that the distribution of both early millet in northern China and rice in southern China shifted from the foothills to the valleys. Despite a great deal of discussion surrounding the relationship between ancient agricultural developments and climate change (Jia et al, 2013;Yang et al, 2018;Zhang et al, 2018), there have been fewer studies of the relationship between agriculture and geomorphologic environments at different stages in prehistoric China (Zhang et al, 2014;Li and Zhang, 2020).…”

Relationship Between C4Biomass and C4Agriculture During the Holocene and its Implications for Millet Domestication in Northeast China

“…Two main domesticated C 4 crops, foxtail millet and common millet, were the staple foods in the semiarid regions of East Asia (Miller et al., 2016). Although the role of North China as the center of origin of millet agriculture has received widespread research attention (Barton et al., 2009; Cohen, 2011; Crawford, 2008; Lu et al., 2009; Yang et al., 2012), the factors driving the origin of millet cultivation are still debated (Cohen, 2011; Gignoux et al., 2011; Yang et al., 2018; Z. Zhao, 2011). Three types of hypotheses are commonly used to explain the rise of agriculture.…”

Spatial–Temporal Variation of Cropping Patterns in Relation to Climate Change in Neolithic China

“…One of the era-defining events in the Neolithic was the development of agriculture across the old world, followed by a substantial increase in the size of population and settlements [9][10][11][12]. Climate change has been considered to be a critical factor in the emergence and intensification of agriculture during the Neolithic period [13,14]. While the changes in temperature follow the same approximate trends in different regions of the Northern Hemisphere [15], precipitation shows distinct patterns affected by local climate (e.g., the arid central Asia and the Asian Monsoon Region) [16,17].…”