People from the steppes of modern-day Russia and Ukraine quickly spread over Eurasia about 5,300 years ago. These "Yamnaya" left a genetic legacy on people from central Europe to the Caspian Sea within a few decades. Due to their livestock herding and highly mobile lifestyle, archaeologists now refer to them as "eastern cowboys.” But evidence of horseback riding was absent from their traditional cowboy image.

Horse bones are rare, and most archaeologists believe that people did not begin riding horses until at least 1,000 years later, despite the fact that cattle bones and robust carriages have been discovered in Yamnaya sites. According to a recent study that was published in Science Advances

Horses may have been domesticated as early as 3,500 BCE, according to genetic and other data. The earliest references to riding, however, appear in historical writings or visual evidence more than 2,000 years later, long after the Yamnaya colonized the steppes. Several archaeologists believed that the eastern cowboys were satisfied to follow their herds of cattle as they walked.

The western limit of Yamnaya expansion, Romania, Hungary, and Bulgaria, yielded more than 150 bones, which the authors examined. The chemical makeup of their bones revealed a protein-rich diet associated with herding cattle and sheep; the Yamnaya were well-fed, healthy, and tall.

Nonetheless, the skeletons revealed noticeable wear and tear.

Many of them showed compression of the spine, which can happen after spending time sitting still while absorbing severe impacts. Moreover, they displayed thick areas on the thigh bone that are consistent with prolonged crouching. Healed broken collarbones, fractured foot bones, and cracked vertebrae—these injuries matched the types of harm that a horse's kick would do or what sports medicine experts see in riders today who have been thrown from their horses.

Strong circumstantial evidence for horseback riding was found when the investigators matched the injuries to those observed in subsequent populations where graves were buried with riding gear, horses, or both.

Almost half of the 150 Yamnaya corpses he examined exhibited alterations similar to those found in later horse riders. According to the authors, a Yamnaya man who was buried in what is now Romania around 2700 B.C.E. had spinal injury from a heavy fall on his behind in addition to all the bone changes typically seen in horse riders. This man's status as a horse rider would have been obvious among a medieval population.

Yet, some other archaeologists are controlling their enthusiasm. They assert that there is no reliable way to confirm what the human bones imply without access to horse bones to look for telltale signs of skeletal injury from riding. They could be said to be grossly over-interpreting a fascinating pattern.

Human skeletal data alone lacks the ability to separate horseback riding from other exercise patterns. Also, although Yamnaya carts, oxen, and yokes have been discovered by archaeologists, riding supplies like saddles and bridles have been completely lost. I believe they have done the finest bio-archaeological job possible in attempting to identify persons who were riding horses. But ultimately, that doesn't imply it's flawless or compelling.

The authors of the research contend that the changes found in human bones are strong circumstantial evidence, particularly in light of indications that the Yamnaya milked horses and genetic evidence for horse domestication in the Pontic steppe not long after the Yamnaya expansion.

Even without equipment, riding a horse is still a possibility. Without specific equipment, riding a horse allows for intense activity. Meanwhile, perishable materials like leather and textiles may have already deteriorated.

Additional evidence, such as horse bones with riding traces like bit marks or spinal injury from the weight of a rider, would support the argument. The group's discovery is really intriguing. But much more work needs to be done.