Who was the first person to ride a horse? The distant descendants of that first rider may have crossed continents and built empires on horseback. But when and where horse riding began is not a simple question to answer. Horse riding began in an era from which little remains of equines survive.
As it happens, we don’t need to find the horse to find signs of people riding it. We could uncover clues from the remains of the human rider. A life on horseback deforms human bones, and thanks to such skeletal marks, archaeologists may have found the earliest evidence of human riding yet—dating back as far as 3000 BC, they report in a study published in the journal Advances in Science today.
“You don’t just have the horse as a mount, you also have the rider,” says Volker Heyd, an archaeologist at the University of Helsinki in Finland and one of the authors of the study. “And we were looking at human beings.”
The skeletons in question were once people of the Yamnaya culture, who lived in what is now southeastern Europe, about 5,000 years ago. But because they died out long before written history, there aren’t many signs of “culture” as most of us would imagine—they could have been one ethnic group or many. Instead, archaeologists have found evidence that the Yamnaya made similar objects and practiced similar lifestyles: These people roamed the steppes, herded cattle, and drove wheeled wagons. Some scholars believe that they spoke a distant predecessor of today’s Indo-European languages. Perhaps most impressively, they buried the dead under towering mounds we call kurgans.
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We know that the Yamnaya had horses, but we don’t know if they only got them for milk and meat or if they rode them. Any riding equipment – bridles and saddles – would have been made from organic materials that had probably long since decomposed.
But horses are only one half of riding. Archaeologists, perhaps, could find the other half inside the Yamnaya kurgans – in human bones that can tell their own stories.
That’s because “primates like us humans aren’t built to sit on horses,” says Birgit Bühler, an archaeologist at the University of Vienna in Austria. “The horse is not made to carry us.” With no saddle or stirrups—something early riders probably didn’t have—maintaining balance requires repeated movement of the lower body and thighs. With all this biological material in motion, riding, like any other mechanical movement, would leave a mark on human bones.
Over decades of repeated stress on the horse, the human skeleton changes in response. The bone tissue in the pelvis and femurs can thicken and thicken. The hip bones can wear together and build up calcium. Vertebrae in the spine can become misshapen and misshapen. And horses can bite, kick, stomp, or throw their riders—all of which can break bones.
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The researchers termed these the symptoms of “riding syndrome” or “riding syndrome.” Other activities may cause individual changes, but the combination of these indicators can be a telltale sign of a lifetime on horseback. Bühler, for example, used this method to study the Avars: horse-riding nomads from the Asian steppes who rode west to rule areas of central and eastern Europe in the early Middle Ages.
Studying bones from 1,500 years ago is already difficult. Studying bones that are three times larger is even more so. But the authors of this study found many signs of horse riding in a 4,500-year-old skeleton from Strejnicu, Romania.
“It was kind of a surprise for all of us to find this out,” says Martin Troutman, an archaeologist at the University of Helsinki and another of the study’s authors.
To further confirm whether the Yamnaya rode horses, the authors examined every bone from this group they could get their hands on, excavated from sites across Bulgaria, the Czech Republic, Hungary and Romania. Some remains were excavated decades ago.
Just because they had bones doesn’t mean they had all the bones. “On average, about half the skeleton is preserved, and the half we have is sometimes very eroded,” says Trautmann. The authors evaluated skeletons from 24 ancient humans based on a list of six criteria that matched the first Strejnicu skeleton. They identified four additional sets of bones—dated to between 3021 and 2501 BC—that fit at least four of the criteria for equestrian syndrome.
We know that humans first domesticated the horse around 4000 BC. we also know that the first chariots appeared around 2000 BC. If these skeletons are evidence for horsemen, then they could provide a key ‘missing link’ between the two.
“It’s not so unexpected if you look at the larger context of Yamnaya,” says Heyd. Archaeologists believe that the Yamnaya civilization spread rapidly across the European steppe in just a few decades – in the time of archaeologists, almost an instant. “You wonder how this is possible without riding,” he says.
It is not definitive proof. The ravages of time, erasing the bones, have made it certain. Bühler, who was not involved in the work but called it a “fantastic paper,” points out that the authors missed one of the key criteria of other research on riding syndrome — the hip socket stretching, vertically, into an oval — because it just didn’t have the hip slots to measure properly.
“It’s not their fault, because the material doesn’t exist,” says Bühler. Future finds may give archaeologists the full skeletons they need, he says. Until then, she says she’s “wary” about interpretations that these people were riding horses.
The authors may yet find these bones – their research in Yamnaya is far from over.