Project description:Through the use of proteomic analysis of 32 dental calculus samples from anceint Mongolia, we show that ruminant dairying was present in Mongolia by at least 3000 B.C.E., over 1500 years prior to previously published work. Excitingly, the earliest site with dairy evidence has been identified as archaeologically Afanasievo, supporting the hypothesis that dairy practices and animals likely entered the Eastern steppe with migrating western steppe populations. Furthermore, at 1200 B.C.E. we detect the first direct evidence for horse milk consumption, demonstrating the Bronze Age origins of equine dairying on the eastern steppe which occurred concomitantly with early evidence for horse bridling and riding in the region. The incorporation of horse milk and riding into early Mongolian subsistence strategies led to dramatic economic and demographic shifts that enabled the formation of the well-known steppe empires.