Origins of equine dentistry in Mongolia in the early first millennium BC

New paper (behind paywall) Origins of equine dentistry, by Taylor et al. PNAS (2018).

Interesting excerpts (emphasis mine):

The practice of horse dentistry by contemporary nomadic peoples in Mongolia, coupled with the centrality of horse transport to Mongolian life, both now and in antiquity, raises the possibility that dental care played an important role in the development of nomadic life and domestic horse use in the past. To investigate, we conducted a detailed archaeozoological study of horse remains from tombs and ritual horse inhumations across the Mongolian Steppe, assessing evidence for anthropogenic dental modifications and comparing our findings with broader patterns in horse use and nomadic material culture.

We conducted a detailed study of archaeological horse collections spanning the past 3,200 y, including those from the Late Bronze Age DSK complex (ca. 1200–700 BCE, n = 70), Early Iron Age Slab Burial culture (ca. 700–300 BCE, n = 4), Pazyryk culture (ca. 600–200 BCE, n = 2), Late Iron Age Xiongnu Empire (ca. 200 BCE–200 CE, n = 3), Early Middle Ages post-Xiongnu period (ca. 100–550 CE, n = 3), and Turkic Khaganate (ca. 600–800 CE, n = 3).

A (top): Contemporary Mongolian herder engaged in horseback riding, using left-handed rein position causing asymmetric pressures to the horse’s skull. Photo by Orsoo Bayarsaikhan. B(center) contemporary Mongolian horse skulls, showing asymmetric and skewed thinning to the nasal bones caused by bridle pressure. C(bottom) Asymmetric deformation to the cranial bones of a Deer Stone-Khirigsuur horse (left), alongside an early Middle Ages horse with a similar feature (right). Modified from Taylor and Tuvshinjargal (2018).


This Late Bronze Age dental modification counts among the earliest documented instances of equine veterinary care, and the oldest known evidence for horse dentistry. At first glance, the detailed historical record of early equine veterinary care in places such as China, Greece, Rome, and Syria, which spans the late second millennium BCE through the early centuries CE (11, 15, 16), might imply that equine dentistry emerged in the sedentary civilizations of the Old World. However, the earliest textual references describe only nonsurgical medicinal treatments and make few mentions of oral health (11). Recent archaeological discoveries suggest that human care of domestic animals was practiced by hunter-gatherers as far back as the Paleolithic (46), and that pastoralists may have occasionally practiced surgical procedures on domestic animals as early as the Neolithic in Europe (47). The evidence presented here indicates that horse dentistry was developed by nomadic pastoralists living on the steppes of Mongolia and northeast Asia during the Late Bronze Age, concurrent with the local adoption of the metal bit and many centuries before the first mention of dental practices in historical accounts from sedentary Old World civilizations.

Our results reveal a fundamental link between equine dentistry and the emergence of horsemanship in the steppes of Eurasia. At the turn of the first millennium BCE, militarized, horse-mounted peoples reshaped the social and economic landscape of many areas of the Eurasian continent. Conflagrations with equestrian peoples, such as those between the Persian Empire and the Pontic “Scythians,” plagued alluvial civilizations from the Near East to India and China, while large-scale movements of people linked East and West in never-before-seen ways (48). The archaeological and historical records indicate that the earliest horseback riding was accomplished without stirrups or saddles, and probably using only bitless or organic-mouthpiece bridles (49, 50). The bronze snaffle bit, and the improved control it provided, was a key technological development that enabled the use of horseback riding for more stressful and difficult activities, such as long-distance transportation and warfare (32). We argue that these technological improvements in horse control were preceded and sustained by innovations in veterinary dentistry by nomadic peoples living in the continental interior. By increasing herd survival and mitigating behavioral and health issues caused by horse equipment, innovations in equine dentistry improved the reliability of horseback riding for ancient nomads, enabling horses to be used for nonpastoral activities like warfare, high-speed riding, and distance travel.

Damage to the retained wolf tooth in a 4-5 year old mummified horse, dating to the 2-4th centuries CE from the site of Urd Ulaan-Uneet in western Mongolia


Archaeozoological data from Mongolian horses indicate that the nomadic practice of equine dentistry dates back more than 3,000 y to the DSK complex, a Late Bronze Age culture associated with the first mounted horseback riding and mobile pastoralism in eastern Eurasia. Attempted removal of deciduous incisors through sawing of the exterior suggests experimentation with dental extraction, but not the removal of wolf teeth. The appearance of extracted first premolars in the first millennium BCE coincides with the arrival of metal bits in the archaeological record and oral trauma linked with metal bit use, suggesting that innovations in dental practice were an adaptation to the mechanical changes in horse equipment. These bronze and metal bits provided greater control over the horse, facilitating the development of military uses for the horse, but also introduced new dental problems with the first premolar. Our results indicate that, coincident with the earliest evidence for metal bit use, wolf tooth extraction was practiced in Mongolia by ca. 750 BCE and continued through the early Middle Ages. These results push back the earliest dates for equine dentistry by more than a millennium and suggest that nomadic peoples developed key innovations in veterinary care that enabled more sophisticated horse control, ultimately changing the structure of communication, exchange, and military power in ancient Eurasia.