Health of Xiongnu and Mongol period populations: a bioarchaeological analysis of pastoral populations from two ancient Mongolian empires

Jacqueline T. Eng1 and Vanchigdash Ch. Mergen2 1Dept. Anth ropolog y, Weste rn Michigan Uni ve rsit y, 2Dept. A rchaeolog y & Anth ropolog y, National Uni ve rsit y of Mongolia

Introduction Skeletal Samples Health variables: Spondylolysis Mongolia has been the home of many pastoral cultures, including several Observations of the skeletal material were * Dental disease: antemortem tooth loss (AMTL), carious lesions, abscesses Horse riding places much force on the back [4, 5], which may lead to stress nomadic confederacies that developed into powerful empires. Two of the most made at the National University of * Nonspecific stress: linear enamel hypoplasia (LEH), porotic hyperostosis (PH), fractures of the pars interarticularis of a vertebra (typically a lumbar), resulting in well known are the Xiongnu (209 BC-AD 155), who clashed often with China’s Mongolia, where they are curated. Burials cribra orbitalia (CO), and long bone measures (humerus, femur, tibia) spondylolysis that can further lead to spondylolisthesis (anterior displacement of early dynasties, and over a millennium later, the Mongol Empire, who under of both the Xiongnu and Mongol period * Activity: fractures, including spondylolysis the vertebra). Five adults in the Xiongnu sample have spondylolysis, all on the fifth lumber (L5), out of 57 adults (9%) with vertebrae for observation, while one Chinggis (Genghis) Khan and his descendants, conquered throughout Eurasia samples analyzed here, following Buikstra Results during the 13th and 14th centuries. Bioarchaeological comparison of skeletal and Ubelaker [3], include those from adult in the Mongol sample of 37 individuals (3%) with vertebrae has Observations of lesions were analyzed via Fisher’s Exact test. They included collections from these two key periods is an ideal means to explore questions multiple sites located throughout Mongolia spondylolysis at L3 (p=0.398). The majority of cases are males (4/6=66%: 4M comparisons within site (male vs. female), between site (total subadult and adult about the impact of changes in social organization over time on the quality of life (Fig. 2). vs. 1 F in Xiongnu; 1 F in Mongol) and four cases (66%) are bilateral (Fig. 4). samples), and between site by sex (e .g ., Xiongnu males vs. Mongol males) (Table and stress experienced by nomadic pastoralists. Figure 2. Sites of skeletal samples from 2). There are no significant differences in any of these comparisons, and Historical Context the Xiongnu and Mongol periods subadults have no lesions except one case of LEH in a Mongol period subadult. The Xiongnu (aka Hunnu in Mongolian) first appeared in Chinese records in the The p-values show how similar the frequencies are between males and females late 3rd century BC (Fig. 1a). They were a confederation of nomadic tribes of the within the Xiongnu sample (suggesting similar levels of dental disease and Ordos steppe region of Mongolia who were a constant threat against the childhood stress), and to a lesser extent within the Mongol sample; there is a J. Eng directly observed 82 Xiongnu samples and 66 Mongol period samples for northern borders of the early Chinese dynasties. These mounted warriors with slightly higher frequency of AMTL and notably, abscesses among females (43% multiple health variables, including long bone measurements (Fig. 3), while M. their superior cavalry formed a nomadic empire in the 2nd century BC that vs. 0% in males, p = 0.06) of the Mongol period. The inter-site adult Vanchigdash measured an additional 47 Xiongnu (n=28 M, 19 F) and 53 Mongol encompassed much of northern and western China north of the Yellow River [1]. comparisons show no significant differences, although there are more differences (n=29 M, 24 F) femora for height data. in these comparisons than in intra-site comparisons. Infighting was common, however, and eventually the Chinese empire recaptured Figure 4. Fractures seen in Xiongnu and Mongol period samples lost lands while the remaining Xiongnu tribes were conquered and/or absorbed Table 2. Intra- and Inter-site comparisons of health variables by later nomadic groups such as the Xianbei by the second century AD. XIONGNU MONGOL INTER-SITE Discussion & Future Research Total 2-sided 2-sided Xiongnu Mongol Subadult Male Female Adults It may be expec te d tha t w ith over a th ousand year diff erence be tween the The Mongol period started with the conquests by Chinggis Khan in the early 13th Figure 3. Demographic profile of samples J. Eng observed for multiple health indicators Variables MFp-value M F p-value subadult subadult p‐value p-value p-value p-value Xiongnu and Mongol periods, the two samples would have had some significant century AD (Fig. 1b). He and his descendents eventually formed the largest AMTL 3/14 2/12 1 1/7 6/14 0.337 0/3 0/5 1 1 0.216 0.326 differences in health indicators. For instance, there was transcontinental contiguous empire in the world, extending from East Asia to eastern Europe and Cavity 1/15 0/12 1 0/8 0/13 1 0/2 0/5 1 0.417 1 1 exchange of knowledge of medicine, agriculture and cuisine, and technology parts of the Middle East. During this period, there was wide-ranging trade and Abscess 3/14 2/12 1 0/7 6/14 0.061 0/3 0/5 1 0.521 0.216 0.505 LEH 3/12 1/6 1 0/6 1/10 1 0/2 1/5 0.515 1 0.340 among other things during the Mongol period. Yet the results show no significant exchange in ideas, technologies, and goods, as well as the movement of people 1 PH 0/11 0/12 1 0/4 0/7 1 0/1 0/2 1 111 differences in the frequencies of the health indicators over the two periods. [2]. The disintegration of the empire in the 14th century ended this Potential Biases CO 0/9 0/11 1 0/2 1/12 1 0/1 0/3 1 1 1 0.412 These results suggest that the shared subsistence pattern of nomadic transcontinental exchange, though the legacy of cultural transmission is still pastoralism, at least within these samples that still lived within Mongolia (and not Sex: Males outnumber females in the Xiongnu sample at 63% compared to evident today in many areas. There are also no significant differences in adult long bone lengths (humerus, at urban centers) and who were likely not members of the upper elite, led to 34%, but this is not quite at the level of significant difference (χ2=3.217, femur, and tibia) when comparing the Xiongnu and Mongol samples (Table 3). similar experiences with respect to the health indicators analyzed here. p=0.07). In the Mongol period, the opposite is seen with 38% males and 62% Table 3. Comparison of adult long bone lengths 2 females, again not at the level of significance (χ =1.619, p=0.20). XIONGNU MONGOL STATISTICS Results show shared risk of back injury and upper extremity fractures, common Long bone N Males N Males t df p today in horse riders [6 , 7] , as well as similar rates of dental disease , likely owing Age: A second potential source of bias is in the age composition within each Humerus 29 308.1 11 321.1 -0.973 38 0.337 to continued consumption of the traditional pastoral diet [2]. Compared to the sample, as some pathological conditions, such as dental diseases are often Femur 57 439.5 41 437.57 0.382 96 0.704 Tibia 28 357 13 351.3 0.896 39 0.376 within site analysis, which showed much similarity within group, there was more progressive, with older individuals more likely to show pathological changes. Long bone N Females N Females t df p variability in frequencies of stress indicators between the two periods, suggesting Samples were determined to fall into the subadult (0-15 yrs) or three adult age Humerus 20 294.4 21 288.1 1.492 39 0.144 Femur 34 407.28 46 404.41 0.55 78 0.584 some slight change over time, though that change was not significant. categories of Young Adult (YA=16-30), Middle Adult (MA=31-45), and Older Tibia 18 328.1 21 323.1 0.795 37 0.432 Adult (OA=45+), or the general category of Adult (A) when an age category Figure 1a. Xiongnu bone bow and iron axes and spear Figure 1b. Mongol period bow and Fractures The sample size was limited, so more observations would strengthen arrows, spears, and chain mail could not be assigned. There are some differences in age categories present for There are no fractures in the subadult samples. The total adult samples of the interpretations of the trends seen here. The comparison of these data to Research Hypothesis: the Xiongnu and Mongol period samples (Table 1). Both periods have Xiongnu and Mongol periods were compared for risk of fractures, which show no populations from other time periods, e.g., Bronze Age before the nomadic Skeletal samples analyzed here both derive from nomadic pastoral groups living underrepresentation of subadults and both have more individuals in the Young significant differences (Table 4). The Xiongnu sample has higher frequencies of pastoral pattern, and to other pastoral populations would further expand our within Mongolia under two periods of strong, multi-ethnic nomadic confederacies, and Middle adult age categories. This is more marked for the Xiongnu sample cranial (1/22, 5%) and nasal (1/14, 7%) fractures while the Mongol sample has knowledge of the impact of the nomadic pastoral pattern on health over time and yet the collections are separated by a thousand years or more. (YA), while the Mongol period has no males in the OA group. no such instances, but with just one case each among the Xiongnu samples, the in different regions. Table 1. Demoggpraphic p rofile of distribution of ag e and sex in Xiongnu and Monggpol samples imppplication is unclear. Both samples have a Null Hypothesis: Both groups share similar frequencies of all health, dental INTER-SITE AkAcknowl ldedgement s XIONGNU MONGOL few individuals with fractures at the clavicle, We thank Dr. Tumen Dashtseveg of NUM for her advice and access to collections and reports, staff and students at NUM Fracture disease, and activity-related skeletal stress indicators owing to shared Age group Indet. Indet. ribs, or hands (Fig 4). Xiongnu Mongol p-value for logistical assistance, WMU’s Jason Glatz for assistance with the map, and Andrew Baker for help with data sorting. MFSex Total % M F Sex Total % subsistence strategy. Cranial 1/22 0/15 1 Literature Cited Subadult 9 11% 12 18% Nasal 1/14 0/9 1 [1] Di Cosmo, N., Ancient China and Its Enemies. 2002, Cambridge: Cambridge University Press. Table 4. Fractures by location and statistical [2] Allsen, T., Culture and Conquest in Mongol Eurasia. 2001, Cambridge: Cambridge University Press. Alternative Hypothesis: Owing to the temporal difference and accompanying Young Ad 15 16 1 39% 4 10 22% comparison Long bone 5/69 2/49 0.698 [3] Buikstra, J.E. and D.H. Ubelaker, Standards for Data Collection from Human Skeletal Remains . 1994, Fayetteville: Arkansas Archaeological Survey. Middle Ad 14 2 20% 8 6 22% [4] Ball, C.G., et al., Equestrian injuries: incidence, injury patterns, and risk factors for 10 years of major traumatic injuries.The American Journal of Surgery, 2007. 193(5): p. changes in knowledge, behavior, and technology between the two periods, there Hand 1/30 2/26 0.592 636-640. Older Adult 10 5 18% 0 7 11% [5] Siebenga, J., et al., Spine fractures caused by horse riding. European Spine Journal, 2006. 15(4): p. 465-471. are differences in some, if not all, health, dental disease, and activity-related Other PC 5/64 4/45 1 [6] Halser, R.M., et al., Protective and risk factors in amateur equestrians and descriptio Journal Unk. Adult 72112% 8 10 28% of Trauma Management and Outcomes, 2011. 5. stress indicators. Spondylolysis 5/57 1/37 0.398 [7] Havlik, H.S., Equestrian sport-related injuries: a review of current literature. Current Sports Medicine Reports, 2010. 9(5): p. 299-302.

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