Introduction

During the Qujialing period, there was a wave of construction of walled settlements in the middle Yangtze River valley, and at least 20 walled settlements have now been discovered in the Jianghan and Dongting Lake plains1,2,3. During the Shijiahe period, most walled settlements were still in use and some of them became much larger such as the Shijiahe mega settlement4. This wave also spread northward to the middle reaches of the Han River (a tributary of Yangtze River) in the north-south junction region, demonstrated by the new finding of Fenghuangzui walled settlement2.

Previous studies of the walled settlements have focused on their functions, zoning, degree of social complexity and relationship with civilization. What people lived on namely the subsistence economy is significant and has attracted more and more attention. Abundant archaeobotanical research shows that during the Qujialing and Shijiahe periods, rice agriculture was well developed in the Jianghan Plain which may support the raising of walled settlements, while the middle reaches of the Han River were characterized by millet-rice mixed agriculture5,6. However, due to the taphonomy environment with acidic soil in the Jianghan and Dongting Lake plains, animal remains were poorly preserved. As a result, it is still quite vague as to how the animal resources were exploited, which limits our comprehensive understanding about the walled settlement. In contrast, in the mountainous areas of the middle reaches of the Han River, settlements without enclosing walls have accumulated a lot of zooarchaeological data7,8,9,10,11. Whether there was difference in subsistence economies between the walled settlements and those without enclosing walls and how the difference performed also need to be clarified urgently.

The Fenghuangzui site is the only confirmed walled settlement in the middle reaches of the Han River, and the northernmost walled settlement in the distribution of the Qujialing culture12. Abundant faunal remains have been unearthed at this site, providing new key information for the above questions.

Fenghuangzui site is located in Yanying and Longwang Town, Xiangyang City, Hubei Province, belonging to the middle reaches of the Han River and at the southern edge of the Nanyang Basin. The site is enclosed by walls and a moat with an area of 140,000 square meters (Fig. 1(1)). Fenghuangzui guards the passages between the Jianghan Plain and the northern region and considered as the regional center of the northwestern part of Hubei during the Qujialing and Shijiahe period9.

Fig. 1
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(1) The layout of Fenghuangzui site (2) site locations referred to in this study (The software ArcGis were used to conduct the map).

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Wuhan University carried out continuous excavations at the Fenghuangzui site from the year of 2020 to 2024, uncovering remains of walls, trenches, terrace courtyards, house, ash pits, kiln, and tombs. It yielded a large number of potteries, stone tools, plant and animal remains, as well as a small amount of jade and turquoise, etc. The remains of the Qujialing Culture (5000-4500 BP), the Shijiahe Culture (4500-4200 BP) and the Meishan Culture (4200-3900 BP) are the most abundant. The construction of wall at the Fenghuangzui site dates back to the Qujialing period and it was abandoned in the Shijiahe period which led the settlement transformed to a moat settlement. After the Meishan period, the site was completely abandoned.

Methods

Materials

The materials of this study were from the excavation area of 2020-2021 at Fenghuangzui, which was located in the southern part of the site, with a total area of 1350 square meters (Fig. 1(1)). Seven houses, four tombs and 101 ash pits in the Qujialing period were excavated. During the Shijiahe period, besides nearly 200 ash pits and 20 tombs, there was one courtyard compose by several houses and ash pits which provides significant clue about the social organizations. The features of the Meishan period were only found in the eastern part of this excavation area including 102 ash pits, several tombs and one kiln. Considering remains from the Qujialing and Shijiahe period being the most abundant, we will present and discuss the faunal remains from ash pits and houses of these two periods. Due to the taphonomy factor, the bones were fragile and highly fragmented. The collection was hand-selected and no sieving was adopted.

In addition to the Fenghuangzui site, other sites in the middle reaches of the Han River, whose zooarchaeological data have been published, will be discussed in this paper, including the Longshangang9 and Xiawanggang7,13 sites in Xichuan of Henan Province, the Dashi10 and Qinglongquan8 sites in Yunxian, and the Diaolongbei site in Zaoyang of Hubei Province11 (Fig. 1). Although these five sites are all located in the middle reaches of the Han River and perform very similar cultural characteristics, their geomorphology is not the same. Four sites in Xichuan and Yunxian are in the low mountainous and hilly areas, while Diaolongbei in Zaoyang is located in the Nanyang Basin, where the terrain is relatively flat and open. During the Qujialing to Shijiahe period, the Longshangang site covered a larger area of up to 200,000 square meters and may have been the regional center of the Xichuan area, and Qinglongquan should also have been the regional center of the Yunxian area. The Xiawanggang, Dasi, and Diaolongbei sites smaller than 50,000 square meters were general village settlements.

According to the paleoenvironmental research at Fenghuangzui, in our study region it was warmer and more humid throughout the Qujialing period, while the climate became drier and cooler by the time of the Shijiahe period14.

Methods for identification and analysis

In terms of the identification of animal remains, we refer to published guide15,16 and the modern reference collections from the Zooarchaeological Laboratory of Wuhan University. The measurements were carried out following von Den Driesch17. We estimate the age-at-death of animals based on epiphyseal fusion, dental eruption, and dental wear patterns. We refer to the research of Silver18, Bull &Payne19, Grant20, Hongo & Meadow21 for pig age estimation, and refer to the research of Koike & Ohtaishi22, Purdue23 and Carden24 for deer age estimation. The Number of Identified Specimens (NISP) and Minimum Number of Individuals (MNI) were used to quantify the faunal assemblage25. The frequency of skeletal elements, expressed as a ratio, was calculated by dividing the minimum number of elements (represented by the most common part of each element) by the expected number of elements for the MNI of this specie26.

Due to the limitations of the identification procedures, some deer remains could not be identified into specific species. Thus, we classified them into four categories according to their size: large, medium, medium-small and small sized deer. Accordingly, the category of large sized deer also contains the remains of Cervus unicolor that were not identified precisely. Thus, to avoid over representation, when counting the MNI, large sized deer and Cervus unicolor were treated as a whole. Similar cases apply in the categories of medium, medium-small and small sized deer.

The evaluation of pig domestication is based on third molar (M3) measurements and linear enamel hypoplasia (LEH). In addition, we analyze the Habitat Exploitation Index for mammals with reference to relevant research methods27,28,29 to discuss how people exploit the surrounding environment. The specific formula is:

$$\mathrm{HEI}=\mathop{\sum }\limits_{i=1}^{n}\left({{THI}}_{n}* {{MNI}}_{n}\right)/\mathop{\sum }\limits_{i=1}^{n}{{MNI}}_{n}$$

Taxonomic Habitat Index (THI) weighing of different species refers to the researches of current zoography and animal ecology30,31,32,33,34.

We will first analyze the faunal remains unearthed at the Fenghuangzui site and discuss the strategies of faunal resource use within the walled settlement including four aspects: meat consumption, livestock management strategies, surrounding habitats and hunting strategies, and the use of mountain resources. Then we will compare Fenghuangzui with the surrounding settlements, in order to explore the status of the walled settlement in the whole region and its relationship with the surrounding settlements.

Results

Taxon and quantification

A total of 2239 specimens and 19 species were identified from the Fenghuangtsui site during the Qujialing and Shijiahe periods. The identified taxa include mammals, fishes, reptiles, and birds, among which mammals are predominant, occupying over 90% of the whole assemblage. It is worth pointing out that bird, reptile, and fish remains would be underrepresented because of the preservation situation and retrieval methods without screening.

Mammals includes pigs (Sus scrofa), dog (Canis familiaris), sika deer (Cervus nippon), sambar deer (Cervus unicolor), muntjac (Muntiacus sp.), buffalo (Bubalus mephistopheles), bear (Ursus thibetanus), tiger (Panthera tigris), lepoard (Panthera pardus), weasel (Mustelidae), flower-faced civet (Paguma larvata), hare (Lepus sp.), brown rat (Rattus norvegicus) (Fig. 2). During the Qujialing and Shijiahe periods, there was no significant change in the proportion of various mammals. In terms of NISP, pigs have always occupied roughly 60% of the total. Deer are second to pigs, accounting for 34 ~ 37% of the total, among which the medium-sized deer represented by the sika deer is the most dominant species, with a small number of sambar deer, muntjacs. Bovidae and dogs were less common. There were also a small number of carnivores, such as bears, tigers, small and medium-sized cats, and weasels. These carnivores were more varied in the Qujialing period, while only tigers and leopards were found in the Shijiahe period. Hare and rodents were very few (Tables 1, 2).

Fig. 2
figure 2

Main species at Fenghuangzui 1. Mandible, Sus scrofa, T1548H172②, #1123; 2. Second phalanx, Bubalus mephistopheles, T1847H29②, #3478; 3.Sacrum, Panthera pardus, T1450③, #1080; 4. Antler, Cervus unicolor, T1747⑥, #2331; 5. Antler, Cervus nippon, T1849H165②, #3897; 6. Antler, Muntiacus sp., TG1H254, #364; 7. Humerus, Panthera tigris, T1748H25②, #2487; 8. Third metacarpus, Canis familiaris, TG2④, #447; 9. Mandible, Paguma larvata, T1847⑦, #3641. 10. Mandible, Felidae sp., T1747⑥, #2294; 11. Pharyngeal teeth, Ctenopharyngodon idellus, T1847⑥, #3029; 12. Carapace, Mauremys reevesii, T1847H166④, #3668. (The scale of NO.1 ~ NO.7 and NO.12 is 2 cm, the scale of NO.8 ~ NO.11 is 1 cm.).

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Table 1 Quantification of identified mammals of Qujialing period at Fenghuangzui
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Table 2 Quantification of identified mammals of Shijiahe period at Fenghuangzui
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Reptiles includes Chinese pond turtles (Mauremys reevesii) and soft-shelled turtles (Pelodiscus sinensis). A total of 211 specimens were identified, among which turtles were the most dominant. The identified number of turtles in the Qujialing and Shijiahe period is 11 and 197 respectively, while there were only three pieces of soft-shelled turtles in both periods.

Most of the avifauna remains were unidentifiable. Only one piece of goose (Anserinae sp.) bone was found.

Among the fish remains, most of them were not identifiable. Based on the dentary bones and pharyngeal teeth, only four specimens including grass carp (Ctenopharyngodon idellus) and silver carp (Hypophthalmichthys molitrix) were identified.

Mollusks were yielded but highly fragmented, only one specimen could be identified as Lamprotula (Lamprotula sp.).

Mortality profile

Considering the sample size, only the mortality profile of pigs and deer will be analyzed below.

Dental eruption and wear data demonstrate pigs from the Qujialing period were mainly 1 ~ 2 years old, accounting for 60% of the total, with a certain proportion of individuals under 1 year old and over 2 years old. No infant individuals aged 0–4 months were found. In the Shijiahe period, pigs were also dominated by 1 ~ 2 years old, accounting for more than 72% of the total, with no individuals aged 0 ~ 4 months and older than 36 months, and the proportion of individuals aged 4 ~ 6 months increased to more than 21% (Fig. 3). Epiphyseal fusion data shows the vast majority of individuals in the Qujialing period lived beyond stage I (0–1 year), while roughly 30% being killed in stage II (2–2.5 years). Only 30% lived beyond stage III (3–3.5 years). The situation during Shijiahe was similar, with fusing and fused rates of 87%, 54%, and 20% in the three stages respectively (Table 3). These profiles were different from that reflected by the teeth and may be related to the preservation bias of unfused limb bones35.

Fig. 3
figure 3

Age profile of pigs at Fenghuangzui based on dental eruption and wear.

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Table 3 Epiphyseal fusion of pigs at Fenghuangzui
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Dental eruption and wear data show the medium-sized deer in the Qujialing period was found in all age stages except 0.5 and 3.5 years old, and more than 40% individuals culled at 8.5 years old. In contrast, only 4.5, 5.5 and 8.5 years old individuals were found in the Shijiahe period (Fig. 4). In terms of epiphyseal fusion, during the Qujialing period, deer were mainly hunted in the stage II (2 ~ 4 years), stage IV (5 ~ 6 years) and over 6 years, with very few individuals in the stage I (0 ~ 2 years) (Table 4). In the Shijiahe period, all individuals lived beyond stage I (0 ~ 2 years) and few were hunted at stage II (2 ~ 4 years). The number of unfused specimens increased considerably in stage III (4 ~ 5 years) but nearly half of individuals still lived beyond this stage. Two kind of results both indicate that the mortality profile in the Qujialing Period were more dispersed, while in the Shijiahe period the age profile is more concentrated, with the vast majority of individuals aged 4 years or older.

Fig. 4
figure 4

Age profile of medium-sized deer at Fenghuangzui based on dental eruption and wear.

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Table 4 Epiphyseal fusion of medium-sized deer at Fenghuangzui
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Morphological analysis

The size of pig is important evidence to determine whether a herd is domesticated or not. The lower third molar (M3) is the most commonly used size indicator36. According to Luo’s comprehensive study in China37, domesticated pigs should be present in herds where the mean value of lower M3 is less than 39 mm. The average length was 36.06 mm in the Qujialing period and 37.39 mm in the Shijiahe period (Table 5, Fig. 5), indicating that domestic pigs should have existed in both periods.

Fig. 5
figure 5

Size of pig’s lower third molar at Fenghuangzui (1) scatter diagram of size, (2) box diagram of length, (3) box diagram of width.

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Table 5 Size of pig’s lower third molar at Fenghuangzui
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Nevertheless, this does not mean that all pigs are domestic ones. The coefficient of variation of size can be used to determine whether different populations existed. According to the research of Rowley-Cowey et al.38, the coefficient of variation for M3 length in a single population would be between 5 and 7. If it is greater than this range, more than one population may be present. The coefficient of variation was greater than 7 for both periods, suggesting that multiple populations including domestic pigs and wild boars may have existed. However, based on the size of M3, wild boar did not make up a large proportion of the overall population. The proportion of samples over 39 mm decreased somewhat during the Shijiahe period (Table 4), possible indicating a more intensive management of pigs to some extent. It should be noted that the sample size was not big due to the preservation situation, and more data is needed in the further study.

Frequency of elements

Considering the sample size, we choose the two most abundant species, pig and medium-sized deer, to analyze in this section.

The results for pig in the two periods were basically the same. The mandible, maxilla and skull were the parts of the body with high rates. The frequency of mandible performed a rate of 100% in both periods. Limb bones were found at a much lower rate, among which the distal humerus, distal tibia, and talus having a slightly higher rate (Fig. 6). This may be related to preservation or higher fragmentation due to the intensive consumption.

Fig. 6
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Frequency of elements of pigs at Fenghuangzui.

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The results for medium-sized deer were generally consistent between the two periods, with the highest rates being for the talus (over 50%). The frequency of other limb bones would be lower (Fig. 7). Due to the “schlepp effect”39, the low frequency of skulls and mandibles may reflect that deer should be hunted and slaughtered outside the site, and less valued portions such as skulls may be not brought back to the site and abandoned in the wild, which is distinguished from the situation of pigs.

Fig. 7
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Frequency of elements of medium-sized deer at Fenghuangzui.

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Abnormality and pathology

In terms of abnormality, Linear Enamel Hypoplasia (LEH) of pigs was the predominant type at Fenghuangzui. During the Qujialing period, there were nine specimens of LEH with a total percentage of 11.8%. During the Shijiahe period, there were 19 specimens of LEH with a total percentage of 12.6% (Table 6). This category of abnormality is associated with physiological stress40,41 and the frequency is over 5% in domestic pigs37. The frequency of LEH in both periods at Fenghuangzui significantly higher than 5% manifests the domestic nature of the pigs. Also, LEH of M2 and M3 exhibited higher rates than M1, and most of them were found in the lower part of the teeth. According to formation time of teeth, Wang et al. proposed that LEH in the lower part of M2 and M3 in central China may be related to food shortages during the winter42 which would result in the hyposecretion of enamel. This shortage may happen at Fenghuangzui as well.

Table 6 Numbers of LEH of pigs at Fenghuangzui
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HEI

In Qujialing and Shijiahe periods, the results of the Habitat Exploitation Index (HEI) show shrub and grassland performed higher values over 0.3, while forest, wetland and river/lake performed much lower values under 0.12 (Table S1 ~ 3). It indicates the people mainly exploited the resources from shrub and grassland.

Discussion

In the following section, the exploitation of animal resources at the Fenghuangzui site will be discussed in terms of four aspects: meat consumption, management of domestic animals, surrounding habitats exploitation and hunting strategies, and the use of mountain resources.

At Fenghuangzui, most bones are fragmented and scattered in features. Also, we observed cut and hack marks on them. These indicate most of them should be the remnants of meat consumption. According to the proportion of species, it can be seen that pigs were the main source of meat, followed by the deer. Large bovidae, despite their small number, were extremely rich in yielding meat at one time, so they should occupy a certain proportion. Dogs few in number were probably mainly raised for guarding or as hunting helper instead of being used for meat. The large carnivores such as tiger and bear should not be for daily meat consumption, but have symbolic functions and meanings which will be discussed detailed in the following section.

According to the results so far, non-mammals such as fish, birds, mollusks, etc. may serve as a supplement to the meat consumption. However, it should consider the bias of preservation and collection methods. The Fenghuangzui site is close to the Paizi River, a tributary of the Han River, and fish may be important for the meat consumption. During the Shijiahe period, the proportion of turtles was significantly higher than that of other non-mammals. Most of these remains were turtle shells and mainly from a special pit H17, which was consisted of 10 layers with intermittent layers of grass and wood ash and yielded a large quantity of pottery. Some small stones were found beside the turtles as well. Based on the elements of turtle and its burial context, we propose the shells were probably used as tortoise rattles, a common ceremonial object in the area.

The size data suggests that domestic animals at Fenghuangzui include pigs and dogs while dogs were few in number. Considering the morphology, the large-sized bovines is likely to be wild buffalo. Due to the small sample size and lack of enough age and pathology information, it is difficult to make a determination as to whether the buffalo were initially managed and even used in rice agriculture for ploughing. Therefore, we only discuss the pig management. At Fenghuangzui, the size of the third molar in pig was not significantly different between the Qujialing and Shijiahe periods and the length maintained at around 36 ~ 37 mm. There was also no significant difference between the two periods in terms of pig slaughtering strategy. Subadult (1 ~ 2 years) were dominant accounting for around 60 ~ 75% of the population. In ancient China, pigs would reach full size at 1 ~ 2 years37, then this stage or earlier are commonly considered as the optimal age of meat acquisition. Therefore, we argue that pigs were raised as meat and the most cost-effective strategy was adopted in both periods.

Wild animals have their specific habitats and living environments. Accordingly, the surrounding vegetation and environment can be outlined to a certain extent based on the wild animals found in the site. At Fenghuangzui, medium and small sized cats reflect that a certain area of forest should existed. Grasslands and bush in the surrounding environment would be demonstrated by sika deer, muntjac, hare. Sambar deer and buffaloes reflect that there were marshes and wetlands as well. It can be seen that the site was surrounded by a diverse habitats and wild resources were relatively rich. This were fully utilized by the residents of Fenghuangzui, resulting in a relatively high proportion of wild animals. The amount of wildlife resources can also reflect the intensity of the ancient people’s exploitation of these habitats. The results of HEI indicates the people mainly exploited the resources of shrub and grassland. However, as mentioned above, the exploitation of wetlands, rivers and lakes represented by fish and birds would be underestimated due to collection methods as well as preservation issues.

Hunting deer were predominant in hunting activities, which is related to their wide distribution43. Both periods were dominated by adult deer, which differs from the strategy of dominating sub-adults in domestic pigs. However, both strategies for deer and pigs are consistent with optimal return utilization. Also, some variation performed in hunting strategy between two periods. Juvenile and subadult individuals were present during the Qujialing period, whereas only adults were hunted during the Shijiahe period. 2 ~ 4 years of age are deer’s optimal breeding period44, and avoiding hunting individuals of this age during the Shijiahe period would be a more sustainable strategy to maintain the deer population45,46. In addition, deer not only provided protein, but also antlers for making artifacts. We observed many cutting, hacking and sawing marks on antlers at Fenghuangzui (Fig. 8). During the Qujialing period, there were 12 antlers that we could determine their shedding situation, most of which (8/12) shed off naturally. During the Shijiahe period, there were 13 antlers that we could determine their shedding situation, most of which (8/13) did not shed off. This indicates that the acquisition of antlers in the later period was more proactive rather than passive collecting shed-off-antler in the wild. Male sika deer would bear full antlers at 3 ~ 4 years old47 and hunting adults would obtain larger antlers.

Fig. 8
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Sawing mark on antler at Fenghuangzui.

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Both tigers and black bears belong to the typical montane forest-habitat animals48. According to current zoological studies, the altitude of the South China Tiger living is usually above 800 meters49, and the terrain where the black bears live is mostly on mountain slopes and crests33. The historical distribution of tigers and bears is also consistent with their current habitat choice. Fossil, archaeological and documentary evidences all demonstrate that tigers and bears in Hubei are mainly located in the mountainous areas and rarely seen in the plains50. A certain area of forest may exist around the Fenghuangzui site, but the terrain is flat with an elevation of roughly 100 meters, which is not a suitable environment for tigers and bears. Then where did the tigers and bears at Fenghuangzui come from?

Roughly 50 km west and 50 km south of the Fenghuangzui site, across the Han River, there are the Wudang Mountain and Jingshan Mountain. Along the Han River to the upper reaches, there are the Qinling Mountain and the Funiu Mountain. In these mountainous areas, many riverine sites from the Yangshao to Shijiahe periods have been found, such as Dasi10, Maling37, Longshangang9, Xiawangang7. The remains of tigers and bears are found in both general and central settlements, suggesting that they were common in this region. The Classic of Mountains and Seas·Zhongshan Jing recorded that tigers were abundant in the Jingshan Mountain. Until the Ming and Qing Dynasties, tigers and bears still existed in this region. Xiangyang County Records recorded the local products from Nanzhang, Zhushan, Shangjin, Junzhou, Fangxian, Yunxian, Guxian in this region included bears and tigers51. It can be surmised that the tigers and black bears at Fenghuangzui probably came from these mountain areas. Related strontium isotope tests are underway.

The tigers and bears weigh at least 100 kg and the largest ones could weigh up to 320 kg. It is important to consider how to transport these animals back to Fenghuangzui. No evidence of animal labor has been found, and waterway is a possible option. The moat of Fenghuangzui was connected to two ancient rivers outside the settlement, which finally flew into the Paizi River and Han River. After the ancients captured tigers and bears in the mountains, it is likely that they went back to Fenghuangzui via the route from Hanjiang-Paizi River to ancient river and then to the site moat.

This implies that Fenghuangzui utilized the surrounding resources over an area of at least 50 km during the Qujialing and Shijiahe Period. What’s important, it also reflects the interaction between Fenghuangzui and the sites in mountainous area, although it could not confirm whether the form of this interaction was top-down or egalitarian. Perhaps the residents of Fenghuangzui entered the mountains for hunting proactively, or they were supplied by other mountainous settlements. Whichever is possible, this kind of utilization is far more symbolic than practical, and may even have political significance. Humans often use the top predator as a symbol of power, and in China the cultural symbolism of tiger has always been prominent52. Obtaining such game would help the hunter or recipient to enhance his prestige and status.

In summary, at Fenghuangzui, the use of animal resources during the Qujialing and Shijiahe periods was dominated by the domestic animals, but people also made full use of the surrounding habitats such as shrub and grasslands to hunt various wild animals, especially during the Shijiahe period the hunting was more proactive and targeted. They even made use of resources in the mountains over long distances for enhancing individual’s prestige. Different exploitation strategies were adopted for the pigs and medium-sized deer which were the main utilized species, but both were consistent with the optimum economic strategy. The use of animals was not limited to meat, but also included using antlers and bones for making artifacts and turtle shells for ceremonial activities. Our research is the first time to reveal the animal resource exploitation strategy of the walled settlement in the middle Yangtze River valley and contributes to a comprehensive understanding about the walled settlements.

Since the Qujialing period, the settlements in the middle reaches of the Han River have developed more significantly, demonstrated by the emergence of larger settlements and obvious differentiation between settlements53,54. The location and scale of the site, the houses with high architectural skills, the jade and turquoise ornaments unearthed all indicate that Fenghuangzui was of high rank and should have been a center settlement in northwestern Hubei12. The drastic social differentiation among individuals within settlement is implied as well. For example, at the Huangshan site in this region, which is about 150 km northeast to Fenghuangzui, a few burials with large quantities of pig mandibles and jade objects were found during the Qujialing period55. The number of pig mandibles was considered as an indicator of the wealth32 and jade is always related with the grade of the buried in China. Then, is there any differentiation in the use of animal resources? what are the similarities and differences between Fenghuangzui (the only walled settlement in the middle reaches of the Han River) and other sites? A comparison will be conducted below.

In terms of faunal composition, during the Qujialing and Shijiahe periods, domestic pigs were predominant, no matter in the regional centers of Fenghuangzui, Longshangang and Qinglongquan, or in the general settlements of Xiawanggang and Dialongbei. Only the Dasi site (smaller than 10,000 square meters) performed a low proportion of pigs, reflecting another situation in the small village sites (Fig. 9). However, not as the situation in the Liangzhu mega walled-settlement in the Lower Yangtze River Valley where the proportion of domestic pig could reach over 90%56, Fenghuangzui was not as highly dependent on domestic animals. This should be benefit from the various use of the surrounding habitats. The scale of settlement is probably another factor. Fenghuangzui is considered as medium scale among the whole middle Yangtze River Valley. People living there may not conduct extreme stress on the environment and could get considerable wild resources from surroundings.

Fig. 9
figure 9

The proportion of mammals (NISP) at sites in middle reaches of the Han River.

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In terms of management strategy for domestic pigs, the Fenghuangzui site is similar to the other sites as well. First, there are no significant differences in size and the average length of lower M3 in all sites were roughly between 36 ~ 37 mm. Second, the mortality profiles were all dominated by 1 ~ 2 years old individuals, with a low percentage of older than 2 years old individuals (Table S4, S5). It differed from the situation during the previous period (namely Yangshao period, 7200-5000 BP) when the percentage of individuals over 2 years old was higher and usually over 20%, which is related to the free-range strategy adopted at that time and the preference for adult individuals for ritual use37. Pigs under free-range strategy grow slower and need to be raised to a much older age in order to obtain enough meat. Based on data from Xiawanggang13 and Qinglongquan8,57,58, this change in mortality profile may be related to the change of feeding practice. Compared to the Yangshao period, the δ13C value of pigs increased during the Qujialing and Shijiahe periods (Fig. 10), reflecting a more intensive control with millet by-products feeding. It would enable pigs to reach the appropriate weight for slaughtering at a younger age. However, the Fenghuangzui site mainly relying on rice59 cultivation differed markedly from the other sites where the millet dominated or millet-rice mixed5 in agriculture. Whether the by-products of rice were used for domestic pig rearing at Fenghuangzui in the same way as the by-products of millet? It requires further isotopic and dental residue analyses to confirm.

Fig. 10
figure 10

Stable carbon and nitrogen isotope values of pigs in middle reaches of the Han River. Ranges are displayed as mean ± standard deviation (Data from the Xiawanggang and Qinglongquan site).

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Regarding deer hunting strategy, there is a lack of valid comparative data from the Qujialing and Shijiahe periods, and comparisons can only be made with the earlier period namely Yangshao period. The hunting strategy of the Qujialing period at Fenghuangzui is similar to that of Yangshao sites with a proportion of young individuals60. Without contemporary data, it is hard to determine whether the strategy of concentrating on hunting adult deer individuals in the Shijiahe period is common in the whole region. Nevertheless, in the later period namely Meishan or Longshan period (4200-3900BP), the Xiawanggang site also had a predominance of individuals over 6 years old7, suggesting this change may have occurred across the region.

If the 2020–2021 excavation area could represent the general situation of Fenghuangzui, then it shows similarity to a great extent with other ordinary settlements and center settlements without enclosing walls in terms of faunal composition, domestic pig husbandry and deer hunting strategy. However, considering its ability to utilize large game in mountain at least 50 km away, Fenghuangzui should still differ from the general village sites. In other words, the differences were not reflected in the basic subsistence of animal exploitation but symbolic resources. Beside symbolic animals, the interaction between Fenghuangzui and the mountainous areas could be manifested by turquoise which was used to make exquisite high-graded artifacts. Yunxian, Yunxi and Zhushan counties in the mountainous area are important turquoise producing loci61,62, and the turquoise found at Fenghuangzui were likely from above area. Obtaining these items scarce in the plain could contribute to differentiation among individuals within Fenghuangzui. It also implies the center role of Fenghuangzui is not because of its economic function, but for other symbolic reasons such as guarding the path to Jianghan plain63, which would certainly affect the pattern of socio-political development in this region.

Finally, the Fenghuangzui site may be representative for the medium-sized walled settlements, but it remains to be explored what the situation of animal exploitation was like at other sites located in the Jianghan and Dongting Lake plains (especially the mega-sites), and how they related to the neighboring settlements. Given the state of preservation, conventional animal bone identification may be difficult to resolve above questions, but applying new technological tools such as ZOOMS, residue detection, and environmental DNA to the poorly preserved remains would likely lead to new breakthroughs.