The horse, a creature that has profoundly shaped human societies throughout history, has been a subject of ongoing scientific inquiry. For centuries, researchers have attempted to unravel the mystery of when and how humans first domesticated this remarkable animal. While early humans hunted horses with spears and utilized their bones for tools as far back as half a million years ago, the first true domestication remains shrouded in ambiguity. The Indo-European hypothesis, also known as the “Kurgan hypothesis,” has long been the prevailing model for horse domestication. This theory proposes that residents of the steppes of western Asia and the Black Sea, known as the Yamnaya, were the first to ride horses, sometime in the fourth millennium BCE. The increased mobility afforded by horses, according to this hypothesis, propelled vast migrations across Eurasia, disseminating Indo-European languages and cultures. However, recent scientific advancements have cast doubt on this long-held theory.
Recent discoveries in the Botai culture of Kazakhstan, dating back to the fourth millennium BCE, have presented tantalizing evidence of horse domestication. Archaeological sites in Botai revealed a wealth of horse bones, along with potential evidence of corrals and ceramic fragments containing horse fat residues. Moreover, Botai horse teeth and jawbones displayed signs of wear consistent with the use of bridles, further supporting the notion of domestication. However, closer scrutiny of the Botai data unveiled inconsistencies. The prevalence of both male and female horses of breeding age, along with evidence of hunting, raised questions about the true nature of the relationship between the Botai people and their horses.
In recent years, advancements in biomolecular technology and archaeological methods have revolutionized our understanding of early horse domestication. Genomic sequencing revealed that the Botai horses were not the ancestors of modern domestic horses but of Przewalski’s horse, a wild species that has never been domesticated. Additionally, a reassessment of skeletal features linked to horse riding in Botai revealed similarities to those found in wild horses from North America, suggesting that the observed changes in Botai horse bones may be attributable to natural variation rather than riding.
Further research has thrown into question the central role of the Yamnaya in horse domestication. A comprehensive genomic study of early Eurasian horses has demonstrated that Yamnaya horses were not ancestors of the first domestic horses, referred to as the DOM2 lineage. Moreover, there was no genetic evidence of selective breeding or inbreeding in Yamnaya horses. The DOM2 lineage emerged just before 2000 BCE, well after the Yamnaya migrations and shortly before the first archaeological evidence of horse burials and chariots appeared. These findings suggest that horse domestication likely occurred in the Black Sea steppes, but significantly later than previously believed, and not directly linked to the Yamnaya culture.
The latest research suggests that the control of horses and their integration into human societies occurred during the early second millennium BCE, coinciding with the widespread adoption of horses and chariots across Eurasia. While the precise timeline and details of horse domestication remain to be fully elucidated, the emerging picture challenges long-held assumptions and necessitates a reevaluation of our understanding of early human societies. The story of horse domestication is a testament to the dynamic interplay between humans and animals, shaping the course of human history and leaving a lasting imprint on the world we inhabit today.
