The domestication of the horse (E. caballus) was a keystone moment in human history, producing dramatic changes to the way people lived, moved, and interacted in societies across the globe. Perhaps nowhere is the significance of horses more apparent than in the steppes of eastern Central Asia. For nomadic herders living in the Mongolian countryside, horses are a critically important livestock animal, as well as the primary means of transportation. Meanwhile, in the urban capital of Ulaanbaatar, horses remain at the center of Mongolian culture and national identity.

Despite their centrality to Mongolian life, however we know very little about what role horses might have played in the initial formation of nomadic societies. Based on archaeological data, some researchers suggest that Mongolian herders completed the transition to a fully nomadic, herding lifestyle during the late Bronze Age (ca. 1200-700 BCE, Fitzhugh 2009). Around this time, people began constructing stone burial mounds, known as khirigsuurs, as well as elaborately carved standing stones known as deer stones (Figure 1, top image).

At both deer stones and khirigsuurs, people constructed small stone burial mounds containing the remains of a single horse – particularly the head, neck, and hooves (Figure 2). However, with no historical records and very few other artifacts dating to this period, it has proven difficult to evaluate precisely how these horses were used, or what role horsemanship might have played in late Bronze Age Mongolian social developments. Consequently, we must turn to new sources of information in order to understand how and why nomadic societies and horse culture developed in the region.

One promising way to address these questions is through the osteological analysis of horse bones from archaeological sites. Unlike many other mammals, a horse’s teeth continue to erupt throughout the animal’s lifetime – a trait known as hypsodont dentition. This unique adaptation evolved in part to cope with the gritty, steppe grass diet of ancient horses, which wears down teeth at astonishing rate (McFadden 1994). Fortunately for archaeologists, having this kind of dentition also means that horse teeth change size and shape in a consistent way throughout the animal’s lifetime. Thus, by carefully studying archaeological horse teeth, researchers can estimate the age a particular animal was when it died.

In a pastoral herd, young male horses must be castrated or culled before reaching breeding age, when they will compete for mates and disrupt the herd’s natural hierarchy. Additionally, herders often cull and eat older animals, especially mares, who have outlived their reproductive usefulness (Levine 1999). By analyzing a large sample of horse skulls excavated from near deer stones and khirigsuurs, we determined that most of the sacrificed animals were very young horses, less than three years of age. Furthermore, female horses in the study sample were quite elderly, as old as 15-20 years or more. This pattern is consistent with the practical requirements of managing a horse herd, and suggests that people were breeding and managing horses as livestock in Mongolia during the late Bronze Age.

Bendrey, R. 2007. New Methods for the Identification of Evidence for Bitting on Horse Remains from Archaeological Sites. Journal of Archaeological Science 34:1036–1050.

Fitzhugh, W. 2009.  The Mongolian Deer Stone-Khirigsuur Complex: Dating and Organization of a Late Bronze Age Menagerie. In Current Archaeological Research in Mongolia, edited by Bemman et Al. University of Bonn, Bonn.

Levine, M. 1999. The Origins of Horse Husbandry on the Eurasian Steppe. In Late prehistoric exploitation of the Eurasian steppe. McDonald Institute for Archaeological Research, Oxford.

McFadden, B. 1994. Fossil Horses: Systematics, Paleobiology, and Evolution of the Family Equidae. Cambridge University Press, Cambridge.

Taylor, W., T. Tuvshinjargal, and J. Bayarsaikhan. In press. Reconstructing Equine Bridles in the Mongolian Bronze Age. Journal of Ethnobiology.