Rethinking the evidence for early horse domestication at Botai

Despite its transformative impact on human history, the early domestication of the horse (Equus caballus) remains exceedingly difficult to trace in the archaeological record. In recent years, a scientific consensus emerged linking the Botai culture of northern Kazakhstan with the first domestication of horses, based on compelling but largely indirect archaeological evidence. A cornerstone of the archaeological case for domestication at Botai is damage to the dentition commonly linked with the use of bridle mouthpieces, or "bit wear." Recent archaeogenetic analyses reveal, however, that horse remains from Botai are not modern domesticates but instead the Przewalski's horse, E. przewalskii-warranting reevaluation of evidence for domestication. Here, we compare osteological traits hypothesized to have been caused by horse transport at Botai with wild Pleistocene equids in North America. Our results suggest that damage observed in Botai horse teeth is likely generated by natural disturbances in dental development and wear, rather than through contact with bridle equipment. In light of a careful reconsideration of the mid-Holocene archaeological record of northern Eurasia, we suggest that archaeological materials from Botai are most effectively explained through the regularized mass harvesting of wild Przewalski's' horses-meaning that the origins of horse domestication may lie elsewhere.