Subsistence strategies and the diversified food resources in the Mijiaya site
The increased evidences from the archaeobotanical and zooarchaeological studies documented that the millet cultivation and animal husbandry (generally with the high proportions, as shown in the Fig. 7 and Table S2, S3) had been dominant in the human subsistence strategies in the Guanzhong area of northern China during the Late Neolithic period (e.g. Yuan 2015; Zhao 2020). The stable isotopic evidences further reflected that the crop millets and livestock had been took as the staple foods for humans, and the crop millets also paid a key role in the animal husbandry in many Neolithic sites, basing on their higher δ13C and δ15N values (Fig. 8 and Table S4), such as Yuhuazhai site (Zhang X et al. 2010; Zhao 2017), Quanhucun site (Zhang J et al. 2010b; Hu et al. 2014; SPIA et al. 2014), Xinglefang site (Hu et al. 2011a; Liu et al. 2013; Hu et al. 2020), Dongying site (Hu 2010; Chen et al. 2016) and Yangguanzhai site (Hu et al. 2011b; Zhong et al. 2020). Meanwhile, the cultivated rice had spread to here as early as the early Yangshao period (e.g. Zhang J et al. 2010a; Zhao 2017), and the rice agriculture had relatively increased in importance in the Longshan period (Fig. 7) (ZAT 2004; Zhang J et al. 2010b; Liu et al. 2013; Zhong et al. 2015). Moreover, the eastward dispersal of the crops and livestock (e.g. wheat, sheep, cattle, etc.) firstly emerging in the western end of Eurasiac continent before 3000 BC also contributed to the more diversified food resources in the Late Neolithic northern China (Frachetti 2012; Dodson et al. 2014; Lu et al. 2017; Liu X et al. 2019). Additionally, the regional geography with warm climate was advantageous for the agricultural and social developments, and it also influenced the human food choices in the Late Neolithic northern China (e.g. Lu and Zhang 2008; Zhao et al. 2020; Lander 2020; Dong et al. 2021; Dong et al. 2022).
This study provides a new evidence for the Mijiaya peoples engaging in the rice agriculture in the Late Neolithic period, since the various rice phytoliths (include the parallel bilobates, rice bulliform and double-peaked glume cells from the rice leaves and husk) were extracted from the pottery residues (Fig. 5). The high δ13C values of the domestic animals (Fig. 8) and the discovery ofη-shaped phytoliths from the broomcorn millet husk (Fig. 5-q) suggest that the Mijiaya peoples also engaged in the millet agriculture, and the raising animals were heavily reliant on the millet-based food. Moreover, the plentiful animal bones and the various bone/horn tools (e.g. arrowhead and awl) found in the Mijiaya site (SPIA 2012; SHCSNU and XMICHPA 2019) document that the animal husbandry and the hunting activity (e.g. pig, cattle, deer, etc.) were also practiced by the Mijiaya peoples. Moreover, integrated with the previous research on the plant microfossils obtained from the Yangshao potteries in this site (Wang et al. 2016), it can be concluded that the various gathering plants, such as job’s tears (Fig. 4), were also used by the Mijiaya peoples. Hence, it can be deduced that the Mijiaya peoples subsisted on the diversified subsistence strategies in the Late Neolithic period, which was advantageous for their social developments.
Pottery functions and the food processing in the Mijiaya site
A large quantity of pottery vessels with various forms were discovered in the Mijiaya site (SPIA 2012; SHCSNU and XMICHPA 2019); the pottery guan-jar is the most common pottery form in the Yangshao and Longshan phases, and these potteries possessed the diversified textures, colors and subtypes (Fig. 6). Previous researches show that the pottery guan-jar with multiple functions (e.g. cooking, storage, fermentation, etc.) were used to process the various foods (e.g. crops, gathering plants, animal fats, etc.) and/or boil water (e.g. McGovern et al. 2004; Wan et al. 2012b; Lanehart 2015; Wang et al. 2017; Sun et al. 2018; Liu L et al. 2019a), which is commonly associated with the pottery textures and/or subtypes. For instance, the cooking potteries were generally made of the sand-inclusion materials for resisting the break during the heating process, and these potteries were generally adhered with the smoked traces; by contrast, the potteries utilized for the presentation and serving of food mainly were clay (Fan et al. 2005; Lu et al. 2018). Moreover, the various subtypes of the pottery guan-jar, respectively with the deep belly, decorative border or two handles, were used to cook the different foods and/or boil water (Sun et al. 2018). In Mijiaya site, the percentage of the sandy pottery guan had obviously decreased (Fig. 6), and a smaller number of potteries were adhered with the smoked traces in the Keshengzhuang phase. This gives a hint that the pottery guan-jar possibly had been reduced in the cooking function in the Longshan period.
As to the stone tools (Yang et al. 2016a), the phenomena of one pottery form with multiple functions were also observed in the pottery pen-basin, weng-urn (Sun et al. 2018; Liu et al. 2018a) and jiandiping-pointed-based amphora (Liu 2017; Sun 2018; Liu L et al. 2019a) in the Neolithic China. For example, the functions of the pottery pen-basin can be briefly summarized in the sandy flat-based basin used for boiling (Yao et al. 2016), the perforated basin used for steaming and funneling (Liu L et al. 2019a), the spouted basin used for fermenting and filtering (Liu et al. 2018b), and the basin with carved grooves used for grinding/crushing, filtering and boiling (Song 1993; Tao et al. 2009; Sun et al. 2019). Meanwhile, the more evidences show that the diversified pottery forms, including li, jia, gui, pen, fu, weng, ding, yan, etc., were all used to cook the food mainly by the boiling and steaming methods, especially in the Longshan period (Lu et al. 2011; Zheng et al. 2012; Lanehart 2015; Yang et al. 2016a; Yao et al. 2016; Sun et al. 2018; Liu et al. 2018a; Sun et al. 2019). In this study, the pottery li and jia with the relatively high percentages had appeared in the pottery assemblage in the Longshan period (Fig. 6), and most of them had the grey-sandy body commonly with the smoked traces. Integrated with the damaged starch grains extracted from the pottery li-tripod vessel (Fig. 4), it can be deduced that the pottery li and jia from the Mijiaya site were also used for cooking food instead of some pottery guan-jar. This is possibly one reason for the changes in the textures of the pottery guan-jar from the late Yangshao phase to the Longshan phase in the Mijiaya site.
Additionally, the pottery assemblage (consists of the globular jar and perforated basin) for the alcohol fermentation from the pre-Yangshao sites in Guanzhong area had been innovated to be a special unit (includes the pointed-based amphora, flat-based bottle, urn and funnel) in the Yangshao period; meanwhile, the shifts of the beer recipes were also contributed by the local agricultural development, especially the millet and rice cultivations (McGovern et al. 2004; Wang et al. 2016; Liu et al. 2018a, 2018b, 2020; Liu L et al. 2019a). Hence, the changes in the pottery assemblages were also associated with the special food processing and the advanced technology. However, the pointed-based amphora as the wine vessel (Liu 2017) disappeared in the Longshan period in the Mijiaya site; meanwhile, some new pottery vessels (e.g. jia-tripod vessel, gui-tripod pitcher, zhong-goblet and he-spouted ewer) had been created (Fig. 6). According to the functions of the same bronze vessels from the Bronze Age sites (McGovern et al. 2005; Wu 2009; Wang 2016; Zhang 2017), some of these new potteries were possibly used as the wine vessels. All of these indicate that the most basic principle of the changes in the pottery forms was to meet the same functional requirements for the food processing during the Neolithic period. Sometime, the potteries and stone tools were used together for the complex food processing (Yang et al. 2016a; Yao et al. 2016). Otherwise, the pottery stoves and stove sites were all unearthed from the different phases in the Mijiaya site. The stoves, as the auxiliary tools for the food processing, provide a new perspective for exploring the efficiency of food processing technology.
In sum, a variety of ways had been taken by the Mijiaya peoples to refine the pottery functions for the complex food processing. These ways were focused on the changes in the textures and/or the diversified functions of one pottery form, the variety of the special pottery assemblages, and the creation and utilization of more new forms. Otherwise, many archeological evidences show that the multiple centers of the pottery production and the utilized pottery assemblages could have been established in the Late Neolithic northern China (Shelach-Lavi and Tu 2017; Li et al. 2022), such as the Dongying site, Quanhucun site, Xiaweiluo site, Xinzhai site, Miaodigou site, Sanliqiao site, as well as the Mijiaya site (Fig. S1). Integrated with the diversified forms and textures (e.g. sandy, clay, plant inclusions, etc.) of potteries with the diverging functions (e.g. cooking, storage, presentation, serving of foods, etc.), many cooking methods (e.g. steaming, boiling, baking, fermenting, etc.) and various foodstuffs (e.g. husking, granule, powder, noodle, etc.) in the Neolithic China (e.g. Song 1993; McGovern et al. 2004; Lu et al. 2005; Tao et al. 2009; Lu et al. 2011; Wan et al. 2012b; Lanehart 2015; Yao et al. 2016; Wang et al. 2016; Yang et al. 2016a, 2016b; Wang et al. 2017; Liu et al. 2018a, 2018b; Sun 2018; Sun et al. 2019; Liu L et al. 2019a; Liu et al. 2020; Guan et al. 2022), it can be deduced that the development of the pottery production and their functional complexity had possibly met the needs of the human daily life. Moreover, combined with the large Yangshao houses, pottery stoves and vessel assemblages, the refining food processing was deemed to be not only for satisfying with the nutritional needs of humans, but also for their spiritual enjoyment in the feasting and ritual activities (Lanehart 2015; Liu et al. 2018a). Hence, the developments of the pottery function and food processing had also potentially contributed to the social complexity in the Late Neolithic China.
Influences of the agricultural development and food processing on the animal feeding practices
The earliest domestic pigs in China can be dated back to the Early Neolithic period (ca. 9000 BP), and the pig husbandry was gradually intensified in the northern China and the pigs were taken as the staple food as well as the ritual use for humans during the Middle and Late Neolithic periods, which was believed to be mainly contributed by the origin and development of the millet agriculture (Luo 2012; Xiang et al. 2017; Dong and Yuan 2020; Zhang et al. 2021; Zhang M et al. 2022). Meanwhile, the pig husbandry also promoted the expansion of millet agriculture owing to the manuring practices by humans in the Late Neolithic northern China (Wang et al. 2018; Yang et al. 2022). The biology, behavior and evolution of pig (Sus scrofa) and its utilization and management by humans have been explored for understanding the pig domestication (Evin et al. 2017; Price and Hongo 2020).
The varied management strategies for pigs were taken by humans, such as keeping them in pens and/or a comparatively free-range manner (Dai and Zhang 2021a, 2021b). The multiple evidences show that the domestic pigs possibly in pens heavily relied on the human leftovers (mainly being the millet-related food consisting of the millet husks, crop residues and others) in the Late Neolithic northern China (Pechenkina et al. 2005; Chen et al. 2016; Zhang et al. 2021; Yang et al. 2022). Additionally, the extant wild boars, being the non-ruminating omnivores, engage in a flexibly foraging strategy; however, they more prefer to consume the vegetable foods enriched with fiber and energy (Marco 2007; Gimenez-Anaya et al. 2008; Weber and Price 2016). Hence, the dietary habits of wild boars are advantageous for their adaption to the crops-related food also with the enrichment of fiber and energy during the management by humans.
The millet husks had been taken as one staple food for feeding pigs in the Late Neolithic period (Yang et al. 2022). It suggests that the humans had mastered the advanced technology of crops husking possibly by using the ground and flaked stones, since these stone tools were abundantly recovered from the Neolithic archaeological sites in the northern China and widely used to process many kinds of plant seeds (e.g. Yang et al. 2009; Liu et al. 2010, 2011; Yao et al. 2016; Chen 2019). The different parts of millet caryopsis were respectively used to feed humans and pigs, which weakened the competition in food between them, and this further impelled the humans to take full advantage of crops to acquire the economic effect. That is why the diets of pigs and humans were dominated by the millets and/or millet-based food almost at the same time, as the development of millet agriculture in the Yangshao period (Fig. 9, Table S4).
Additionally, the development of pottery industry had advanced the dietary changes in the universally cooking food for humans during the Neolithic period (Sassaman 1993; Yang et al. 2014; Shelach-Lavi and Tu 2017). There is no direct evidence that the humans had specially cooked the food for feeding the domestic pigs, but some leftovers from the human cooking food were generally consumed by the managed pigs (e.g. Pechenkina 2005; Guan et al. 2007; Hu et al. 2009; Chen et al. 2016), and the ethnology investigation shows that the crop husks were simply boiled for feeding pigs in Guanzhong area, northern China. These give a hint that the adaption evolution of domestic pigs and the intensified pig husbandry were also possibly contributed by the food processing. This also provides a new perspective to understanding the pig domestication in the Neolithic China.