We may never know when a human first hopped on a horse and rode off into the sunset, but archaeologists are hard at work trying to understand how horses left the wild and joined humans on the road to the sun. global domination. New research claims to have found the earliest evidence of horsemanship.

A team of scientists reports that humans may have ridden horses as early as 3000 BCE.—about 1,000 years before the earliest known artistic depiction of a human astride a horse. The discovery, described in a study published March 3 in Progress of sciencedepends on skeletal analysis of human remains found in Eastern Europe.

“I always assumed we would find it at some point,” says Katherine Kanne, an archaeologist at University College Dublin, who was not involved in the new research, of signs that humans were riding horses earlier than previous evidence suggested. “Many of us have suspected this for a long time, and for it to come true is really exciting to see, and rewarding for sure.”

To date, researchers have assembled only a patchy timeline of how humans have used horses. Around the year 3500 a. C., humans appear to have been milking early domestic horses, a delicate process, which shows that the animals were already quite tame. but a recent genetic analysis suggests that the lineage of modern domestic horses did not emerge until about 2000 BC. C. It is approximately at the same time that chariot wheels and artistic representations of horsemanship begin to appear. Both indicate uses that would require fully domesticated animals.

The new study addresses the challenge by focusing on human skeletons. Many of the remains he examines are from the Yamnaya people, long associated by archaeologists with horses, who roamed much of Eurasia from their origins in present-day western Russia between 3000 and 2500 BCE. C. “The Yamnaya are extraordinary,” says study co-author Volker Heyd, an archaeologist at the University of Helsinki. He notes that the group’s influence across Europe continues to this day in, for example, the Indo-European languages ​​spoken across the continent.

Heyd and a large group of his colleagues had set out to survey the Yamnaya kurgans, or burial mounds, in eastern Europe. These structures and the items they contain are the only remaining vestiges of culture. Co-author Martin Trautmann, an anthropologist also at the University of Helsinki, was stunned by a familiar pattern of markings associated with frequent horseback riding on the skeleton of a man in his 30s. These patterns, called “jockey syndrome,” occur when bones adapt to biomechanical stress caused by repeated motion. “Bones are living tissue in living things,” says Trautmann. “You can read the life histories of the bones.”

Horseman syndrome involves changes in the bones of the thigh, pelvis, and lower spine. Trautmann had seen these alterations in countless skeletons from much later time periods. “Horseback riding is a very specific pattern of biomechanical stress,” he says. “You use the muscle groups in a way that you normally don’t in everyday locomotion.”

Trautmann was initially hesitant to link the markings to horsemanship, but soon found similar patterns on additional skeletons from the same era. In all, the new paper reports five skeletons from Yamnaya showing at least four of six of those traits out of a total of 217 skeletons included in the kurgan survey.

However, not all of the skeletons were preserved well enough to allow the researchers to assess all components of horseman syndrome, leading to some gaps in their assessments. “It is a fascinating article. I love it,” says Birgit Bühler, an archaeologist at the University of Vienna, who was not involved in the new research. “But I would be cautious because of these missing criteria.”

And because the research focuses exclusively on human remains, not everyone is convinced that the analysis shows that humans were riding horses specifically, despite the Yamnaya’s long scholarly association with horses. “Those pathologies could be totally involved with animal transport, but I don’t see any real evidence here to link them to horses,” says William Taylor, an archaeologist at the University of Colorado Boulder, who was not involved in the new research. Unlike riding a horse, scientists have no idea what traces other types of animals leave on a human’s skeleton, a gap he says he hopes researchers will begin to address.

Trautmann says he suspects that riding animals that are similar enough to horses, such as mules, would leave signs of jockey syndrome. Although he is pleased with the scattered horse bones found at the Yamnaya sites, he hopes that one day scientists will analyze those remains for corresponding skeletal signs that a horse used to carry a rider.