The museum of Hamin Mangha site in Inner Mongolia Autonomous Region Photo: Wang Minghui/CASS

In ancient times, there were many causes of human accidental death, which can be largely divided into natural factors and social and cultural factors. Natural factors generally refer to violent and unavoidable natural events such as earthquakes, floods, mudslides, hurricanes and other violent geological and weather shifts, which can cause the rapid and large-scale accidental death of humans. Natural factors are often seen in archaeological discoveries, such as the ruins of Pompeii in Italy and the ruins of Lajia in Qinghai Province. 

Many accidental deaths are also caused by social and cultural factors. The most common causes are social violent conflicts, such as the cause behind a large number of human remains found at the sites of the Battle of Changping (c. 262–260 BCE) and the Battle of Gaixia (202 BCE). Social and cultural customs can also be a cause, such as seen in the human sacrifices unearthed in the site of Yin Xu in Henan Province. These irregular deaths generally left observable traces on human remains, such as fractures, trauma and abnormal bone loss. At some sites, the specific details of the conflict can even be judged through funerary objects, such as through the position of arrows and the marks on the bones caused by weapons.

Epidemics are another important cause of accidental death, and they might be related to both natural factors and social and cultural factors. However, epidemics are hard to confirm through the study of remains. 

There are various types of epidemics, with various causes. Weather, environmental damage, unqualified medical and health care, unhealthy lifestyles, etc. can contribute to them. In addition, epidemics caused by close contact with animals can be divided into passive contact and active contact. The former refers to the close contact between human habitats and certain animals carrying viruses. The latter usually happens in the process of eating, taming or petting a virus-carrying animal.

Hard to verify

In addition to mass abnormal death, epidemics may also cause great social and cultural unrest and changes. In history, epidemic disasters may have been an important contributor to great population migrations, the replacement of one culture by another, the change of dynasties, or the outbreak of a war. Although historical records relating to epidemics abound, there are few confirmed archaeological discoveries. In addition to the accidental nature of archaeological excavations, the lack of accurate interpretation of archaeological discoveries could also be to blame.

Many prehistoric sites and archaeological sites in border areas cannot be verified due to the lack of documentary records. Even if during periods with relatively rich literature, less attention has been paid to collecting ancient human bone materials. For the small number of archaeological discoveries that may be related to the documented epidemics, few multidisciplinary studies have been conducted for comparison. The research of ancient medical archaeology has focused primarily on traditional and unearthed literature as well as a few unearthed relics, such as stone needles for acupuncture, traditional Chinese medicinal materials, medical appliances and human body models. Less attention has been paid to the diseases found in ancient human remains. 

In recent years, with the improvement of archaeological technologies and the increasing attention to the study of ancient human remains, the study of skeletal pathology has been emerging. Archaeologists hope that through the study of ancient human remains, they can further understand the health conditions of ancient people, the development history of some diseases and these diseases’ relationship with human development.

Skeletal pathology research focuses on bone variations, namely the difference between bones caused by a certain disease and normal bones. The variations can help reveal the causes and the results of diseases, explore the relationship between human health and social and cultural transitions along with changes in the means of livelihood, and ultimately solve the questions concerning archaeology and health history. 

However, generally speaking, only severe social conflicts and geological and climatic phenomena can lead to rapid changes in bones. Bone changes caused by diseases usually emerge through a relatively long process. A disease usually first invades into soft tissues, organs or bone marrow, and it spreads to the bones only after long-term growth. Most diseases that can be detected in bones are not fatal in a short period. Instead, they usually have already been carried by patients for a long time, such as syphilis, anemia, enamel hypoplasia and degenerative joint disease.

As an acute infectious disease, an epidemic is characterized by a short cycle, high lethality and strong infectivity. Because an epidemic would take the lives of infected people in a short time, pathogens generally do not have enough time to deposit on human bones or to change the shape of bones. Even though some epidemics may cause bone changes, such changes are more likely to be tiny and partial. It is still difficult for bone morphology research to effectively observe them. 

Circumstantial evidence

As such, the current few archaeological studies on epidemics are generally based on circumstantial evidence, such as archaeological background, burial objects, burial customs and taphonomy (a branch of paleontology that deals with the processes of fossilization). Inferring the formation of remains through chains of evidence may even be the only feasible approach.

Hamin Mangha site in Inner Mongolia Autonomous Region is one of the few sites recognized by most archaeologists to be potentially related to epidemics. From 2010 to 2013, the Inner Mongolia Autonomous Region Institute of Archaeology and the Research Center for Chinese Frontier Archaeology of Jilin University jointly excavated the site, unearthing over 1,000 pieces of relics including pottery, stoneware, jade ware and articles made of bone, horn and mussels. The radiocarbon dating results indicate that the site is about 5000–5500 years old, largely equivalent to the period of the late Hongshan culture. 

The excavated houses are all semi-underground buildings with rectangular or square surfaces. Some houses have preserved traces of wooden structures that collapsed due to fire. Human skeletons, representing at least 181 individuals, are piled up in several houses. Among them, at least 97 people were placed in the mere 18.5-square-meter dwelling. Three layers of human bones concentrated within the four square meters near the doorway. In each human skeleton, the skull, torso and limb bones are kept in their original anatomical positions, while the postures vary, with no obvious rules, and some bones show traces of burning. Excluding factors such as natural disasters and social violent conflicts and including knowledge from taphonomy and archaeology, some scholars believed that the deaths of these people may be related to a certain epidemic. Some further suggested that it may be related to the plague virus carried by local voles.

Archaeologists have begun to think from multiple perspectives about the archaeological phenomena that were difficult to explain in the past. In terms of numerous abnormal deaths in some prehistoric archaeological sites, the factor of epidemics can also be taken into account after excluding other causes, even without corresponding evidence in literature. 

For example, in the prehistoric site of Miaozigou in Inner Mongolia Autonomous Region, 41 of the 42 tombs are abnormal burials. The bodies are buried in the cellars inside or outside the house or buried in the living spaces of the houses. The skeletons display different postures, with different genders and ages, and there are no signs of violent conflict on the bones. The excavators believed that the burial process was relatively simple and cursory, lacking due procedures and normal burial items. Some scholars believed that the era and environment of the Miaozigou site is similar to that of Hamin Mangha site, both of which may have encountered similar epidemic disasters.

These large numbers of abnormal deaths and burials found in archaeological sites may be a way of isolating patients before their death, or quarantine measures taken against the dead to contain transmission of the disease. It can be speculated that when prehistoric residents were threatened by epidemics, they may have quarantined the infected people or areas. Through isolation, incineration, migration and other measures, ancient epidemics may have been effectively controlled while leaving us relevant archaeological remains. 

Since the 21st century, archaeological technology has been continuously improved. In particular, the introduction of molecular biology techniques into archaeological research has greatly increased our ability to probe into the lives of ancient people and their societies. In 2015, the journal Cell reported the research of some bioarchaeologists who found direct evidence of plague in human bone materials at several sites in Eurasia 5,000 years ago, the most direct and conclusive research on epidemics in ancient human remains. It is expected that in the future, this technology will be applied more often to Chinese archaeological research on ancient epidemics.

Wang Minghui is an associate research fellow from the Institute of Archaeology at the Chinese Academy of Social Sciences.

(Edited and translated by YANG LANLAN)