Critical window for horse domestication
Previous research suggested that the original home of domesticated horses was at the Botai site, in what today is northern Kazakhstan, in Central Asia, because it provided the oldest archaeological evidence of these animals. But DNA told a different story. The Botai horses, which lived 5,500 jare terug, could not be traced to modern domestic horses. Other potential origin sites in Anatolia, Siberia and the Iberian Peninsula didn’t pan out, óf.
Orlando and his team knew that the time period between 4,000 en 6,000 years ago was a critical window for investigating when horses became domesticated due to the dating of ancient horse remains, “but no smoking gun could ever be found,” hy het gesê.
The researchers broadened the search to provide a bigger picture, studying DNA from ancient horses that lived between 50,000 BC and 200 VC. When this was compared with modern domestic horse DNA, the team was able to pinpoint a time and place.
“Horse domestication was an absolute lightning strike in human history, leading to incredible, wydverspreid, and lasting social transformations all across the ancient world,” Taylor gesê. “Horses were an order of magnitude faster than many of the transport systems of prehistoric Eurasia, allowing people to travel, communicate, trade and raid across distances that would have previously been unthinkable.”
The spread of domestic horses
Eurasia was once the home of genetically distinct horse populations, but a dramatic shift occurred between 2000 BC and 2200 VC, the researchers said. A dominant genetic horse population appeared on the Western Eurasian Pontic-Caspian steppe of North Caucasus, east of the Dnieper River within the Don and Volga basins. This area is now part of Russia.
This horse population then spread out and replaced the wild horse groups roaming across Eurasia within centuries.
“What our data show is that between 4,600-4,200 jare terug, herders located in the Don-Volga region found a way to increase the local horse reproductive pool,” Orlando said. “That means that they could reproduce more and more such horses generation after generation. They also selected horses with specific traits.”
Within the horses’ DNA was evidence of domestication, including genes associated with more docile behavior, endurance, stress resilience and a stronger backbone to support more weight. All of these are connected with horseback riding in modern animals.
Horseback riding, as well as the invention of spoke-wheeled war chariots, likely enabled these horses to replace other populations within 500 jare — and forever changed human mobility and warfare.
“The reason why we are so much interested in horses is that they can probably be considered as one of the animals that most impacted human history,” Orlando said. “This tight relationship that we have developed with this animal lasted until the early 20th century, a time when the motor engine took over transportation.”
In the Mediterranean and Mesopotamia, horse-drawn chariots probably spread through trade and military conquest because horses were so crucial as transport animals, Taylor gesê. In places like Central and East Asia, horses also served a valuable purpose as livestock and traveled with migrating horse herders.
Techniques to trace domestic horse origins
Based on the environments where horses lived, “the domestication of horses made the steppes and prairies of the world into cultural centers, population hubs, and political powerhouses,” Taylor gesê. “Nearly everywhere they were introduced, from the steppes of Asia to the Great Plains or the Pampas of the Americas, they reshaped human societies almost immediately.”
Orlando and his team used innovative DNA techniques to distinguish this early horse population from so many others
. The researchers want to eventually understand the entirety of how horses were domesticated
, something Orlando and his colleagues are focusing on through the Pegasus project
. This could also help them learn how domestic horses were introduced to North and South America
“Even though we now know (waar) domestic horses first emerged, the whole process of their expansion around the world and their breeding history into the hundreds of different types that we know today remains contentious,” Orlando said.
“Daarbenewens, the horse was equally the animal of farmers, warriors and kings; they were found in rural and urban contexts alike, and in extremely diverse environments, from the coldest Siberian range to the Nepalese mountains. We want to track how these various contexts have reshaped the horse biology.”