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Skeletons unearthed from graves in southeastern Europe bear the earliest known evidence of horse riding in the archaeological record, new research has revealed.
Horseback riding was a pivotal development in human history — transforming agriculture, transport and warfare — but exactly when humans figured out how to clamber on a horse’s back and steer the animals to go from points A to B has been difficult to pin down.
However, a study published last week in the journal Science Advances found that nine people buried 4,500 to 5,000 years ago who lived in what’s now Romania, Bulgaria and Hungary had patterns of wear on their leg bones, spines and pelvises that suggest they regularly rode horses.
The researchers examined 217 skeletons found in burial mounds called kurgans in Romania, Bulgaria, Hungary and Serbia.
To detect whether the people buried in the graves were horse riders, the researchers outlined six criteria they said were hallmarks of horse riding. For example, the up-and-down movement associated with the activity can damage the spinal vertebrae, and the use of thighs to grip the horse can result in wear at the point where the thigh muscles join the thigh bones.
“Bones reflect the life of a person,” said lead study author Martin Trautmann, a bioanthropologist at the University of Helsinki.
“If you sit on horseback, and especially if you don’t have stirrups, you have to hold fast. And you do that by clenching your legs together and the hip abductor muscles. You also have to balance all the time to avoid slipping from the horse. So the trunk muscles have to keep you erect in relation to your pelvis,” he explained, adding that modern-day horse riders, such as cowboys, showed similar patterns of skeletal wear and tear.
In total, 24 individuals in the graves studied showed some of these signs — although only nine of the skeletons studied displayed at least four of the six criteria, which clearly marks them as horse riders, according to the study. Of these nine, all thought to be the remains of men, five had five of the characteristics and one well-preserved skeleton from Romania exhibited all six.
Most of the skeletons belonged to a group of people known as the Yamnaya, cattle and sheep herders who originated on the Pontic-Caspian steppe that stretches from southeastern Europe into Kazakhstan, skirting north of the Black Sea and Caspian Sea along the way.
“You can call them the first nomads in the world,” said study coauthor Volker Heyd, a professor of archaeology at the University of Helsinki. “From the end of the fourth millennium BC onwards, we see them spreading towards the east and the west. They were on a dramatic expansion drive. In relation to our findings that they were riding horses, then this expansion over 5,000 or 6,000 kilometers makes sense.”
It’s thought that horses were likely first domesticated for meat and milk before being ridden.
DNA analysis has suggested that horses were first domesticated about 4,300 years ago in the steppes of the Black Sea region, part of modern-day Russia, before spreading across Asia and Europe in the centuries that followed.
The first horse-drawn chariots are thought to have been used about 4,000 years ago.