The secrets of Scythian horses
In April 2017, the scientific journal Phys published the results of research by Western universities on the most sacred animal for all nomads — the horse. This study also touched upon another issue – the Scythians, for whose lineage Russians, Ukrainians, and Turkic peoples sometimes fiercely compete to claim as ancestors. Below is the summary of the publication.
From the 9th to the 1st century BC (the Iron Age), Scythian nomads lived and freely moved across the vast territories of Central Eurasia. As herders and hunters, living in proto-yurts on wheels, they entered history as skilled warriors who were the first in the world to master horseback combat and invent the composite bow.
An international team of 33 experts from 16 universities, led by Professor Ludovic Orlando from the Centre for GeoGenetics at the Natural History Museum of Denmark, conducted a separate study on how the Scythians bred their horse breeds. These animals were perfectly suited to their lifestyle and the necessity of assisting humans in numerous economic and military tasks.
DNA Research Results The material for the study was obtained from the burial sites of Scythian nobility in Tuva (the site of Arzhan) and Eastern Kazakhstan Region (the site of Berel, the famous mystical Valley of Kings), where archaeologists discovered about 200 horse bodies in burial chambers in permafrost soil. For the genome analysis, 11 horses from the burial in Kazakhstan and 2 from Altai were selected. DNA analysis showed their ages to range from 2300 to 2700 years, and the ability to trace the geographical distribution of DNA in a historical retrospective helped establish that 4100 years ago, the common ancestor of these 13 stallions lived in the area of the modern Russian city of Chelyabinsk.
This period in Siberian history is called the Sintashta culture by scientists. It gifted the world with the first example of a universally applicable two-wheeled chariot, powered by domesticated horses.
The study of DNA established the coat colors that were not different from those of modern times. Researchers identified bay, dun, roan with spots, among others. The Scythian horses, or more precisely their mummified remains subjected to DNA analysis, did not show mutations responsible for alternative types of equine gaits, meaning these individuals were not natural pacers. However, some, but not all of them, carried genetic variations that are observed today in prize-winning racehorses, adapted for rapid, sprint-like acceleration over short distances. This implies that the Scythians preferred to keep horses of varying endurance and speed potential, i.e., intended for different tasks.
With the exception of two individuals, all of them were not related in life, which, according to scientists, confirms Herodotus’s description of the customs and morals of nomads: the horses sacrificed in funeral rituals were brought from a multitude of allied tribes scattered across the vast steppes of Eurasia.
None of the horses were the result of inbreeding – the Scythians knew how to maintain the natural structure of the herd and natural selection, and did not engage in deliberate selective breeding based on the use of a limited pool of the best pedigrees. This contrasts with modern practices, where one stallion can sire hundreds of offspring. The selection was of a different kind – DNA analysis traced 121 genes involved in the development of the forelimbs, indicating the Scythians domesticated and selected the strongest and most well-developed individuals. Professor Ludovic Orlando states that the group consciously set aside the stereotype of nomadic fierceness to understand how delicately and carefully the nomads treated everything related to horse breeding.
Conclusions of the Geneticists The history of horse breeding begins approximately 5500 years ago. The analysis of horse remains extracted from Scythian burial mounds and their comparison with modern racehorses revealed that in the last 2300 years, there has been a demographic collapse. As a result, there has been a significant reduction in the genetic diversification in the global population of domesticated horses. This means that over this period, humanity has, albeit invisibly, consistently reduced the pool and number of breeding stallions to such an extent that virtually all domesticated horses today are carriers of identical, or very similar Y-DNA.
In the Scythian herds of horses, many Y-chromosomes coexisted, ensuring a great diversity of healthy male lines. This was the case for the first three thousand years of horse breeding. Then, this practice diminished over the last two thousand years. This contributed to the accumulation of harmful mutations in the horse genome, mutations that undermine the animal’s natural physical characteristics. However, the early stages of horse domestication, i.e., the times of the Sintashta and Scythian cultures, were not characterized by such deviations. As mentioned earlier, the analysis of Scythian stallion remains showed a strong genetic difference, not in favor of modernity. To elaborate, there is a widely accepted hypothesis of «domestication costs». According to this hypothesis, the taming of wild animals leads to a genetic burden on them, which in turn promotes the development and accumulation of genetic mutations. Therefore, the group believes that the Scythians had some secrets, the application of which made Scythian horse breeding an exception to the general rule of «domestication costs». This issue remains open and subject to further prolonged study.
The group developed their secret methodology for statistical calculation of signatures of positive selection in the genome at the early stages of horse domestication. They discovered that those genomic regions where the most numerous and pronounced signatures were observed were the regions where nature in its evolution reached the creation of the neural crest. This is a crucial part of the vertebrate organism, from which nerve ganglia grow, responsible for the mechanics and dynamics of galloping, among other things. Thus, the group found regions where the first coherent and logically complete horses appeared, which were later domesticated by proto-nomads.