Sheep have been an integral part of human civilization for over 11,000 years, and their domestication has played a crucial role in shaping human diets, cultures, and economies. Beyond being a source of meat, sheep provided essential protein-rich milk and wool for creating warm, water-resistant fabrics. The relationship between humans and sheep has deep historical roots, influencing everything from farming practices to migration patterns and the development of cultures.
Recently, an international team of researchers has uncovered important insights into the prehistoric evolution and migration of domestic sheep. Led by geneticists from Trinity College Dublin and zooarchaeologists from LMU Munich and the Bavarian State Collections of Natural History (SNSB), the team analyzed 118 genomes extracted from archaeological bones that span 12,000 years and cover regions from Mongolia to Ireland. The findings, which shed light on the cultural and genetic history of domestic sheep, were published in the prestigious journal Science.
Uncovering the Origins of Sheep Domestication
The study reveals fascinating details about the genetic trajectory of sheep domestication. One of the earliest known sheep-herding villages, Aşıklı Höyük in central Turkey, provided key evidence showing that the first domesticated sheep populations were likely the result of capturing wild mouflon in the northern Fertile Crescent over 11,000 years ago. These early domesticated sheep in the region formed the genetic backbone of future sheep populations across much of the Middle East and Europe.
As the research progressed, the team focused on the genomic evidence of early sheep populations across Europe. The data revealed that by 8,000 years ago, the first European sheep herders were intentionally selecting their flocks, particularly for traits like coat color. This practice represents one of the earliest examples of human-directed genetic selection, demonstrating that early farmers were interested in the aesthetic qualities of their livestock, much like modern farmers. The team found evidence of a specific gene, known as “KIT,” which is associated with white coat color in sheep, marking a significant moment in the history of human-animal interactions.
The Spread of Sheep and Their Genetic Divergence
By the time of the Bronze Age, sheep populations had spread widely across Eurasia. The study found that sheep genomes began to diverge in different regions, with early domestic sheep from Europe, Iran, and Central Asia showing distinct genetic differences. However, these separate genetic lines were not permanent. Over time, sheep were translocated from eastern regions to the western parts of the continent, further complicating the genetic landscape.
Two major historical events helped shape the genetic makeup of sheep across these regions. First, around 7,000 years ago, there was a westward movement of sheep populations within the Fertile Crescent, in tandem with the spread of early human cultural influences originating from the burgeoning cities of Mesopotamia. Second, the rise of pastoralist societies in the Eurasian steppes, which began around 5,000 years ago, further altered the genetics of European sheep populations. This period of human migration also had a profound impact on human populations, altering their genetic makeup, as evidenced by the shift in the ancestry of British peoples during this time.
The researchers discovered that the migration of pastoralist peoples brought significant changes to both human and sheep populations. By the time the Bronze Age arrived, sheep herds in Europe were found to carry nearly half their genetic ancestry from Eurasian steppe populations, suggesting that the rise of sheep herding was a key driver of these migrations. Sheep were not merely a source of meat; they also provided vital products such as milk, which could have been used for cheese production, further incentivizing the spread of sheep herding practices.
The Significance of Sheep Migration in Human History
One of the key findings of the study, as outlined by Dr. Kevin Daly, an Assistant Professor at UCD School of Agriculture and Food Science, was the discovery of a major prehistoric migration of sheep from the Eurasian steppes into Europe during the Bronze Age. This migration closely parallels human migrations of the same period, suggesting that, just as people moved across the continent, they also brought their sheep with them. This further underscores the deep interconnection between human and animal migration during this transformative period of history.
The research team, led by Dan Bradley, a Professor of Population Genetics at Trinity College Dublin, emphasized that this study highlights the evolution of human-sheep relations over millennia. From the early days of sheep domestication to the development of wool production and the use of sheep for milk and meat, sheep have been a critical part of human cultural and economic development. The researchers also noted that while the initial domestication of sheep began in the Fertile Crescent, their spread throughout Eurasia and Africa led to the development of many different sheep breeds, which are often referred to as landraces.
A Call for Further Research
While the study provides groundbreaking insights into the genetic history and migration of sheep, Joris Peters, a co-corresponding author of the study and Professor of Paleoanatomy at LMU Munich, emphasized that much more research is needed to fully understand the complex patterns of dispersal and genetic selection that led to the diversity of sheep breeds we see today in Eurasia and Africa. The study of these landraces will require further interdisciplinary research combining genetic, archaeological, and morphological evidence to create a fuller picture of how humans and sheep have shaped each other over thousands of years.
Conclusion
Sheep have played an essential role in the development of human civilization, providing not only sustenance through their meat and milk, but also offering materials for clothing and textiles. Through their genetic history, scientists are now able to trace the spread of sheep across continents and uncover how human cultures and animal breeding practices influenced one another over millennia. This research, led by geneticists and zooarchaeologists, sheds new light on the deep historical relationship between humans and sheep, from the earliest domestication of wild mouflon to the complex migrations of pastoralist societies. Sheep not only helped define the agricultural and economic practices of past cultures but also continue to play a role in the cultural identity of societies around the world. As new technologies in genetic research and archaeological excavation emerge, the genetic legacy of sheep will continue to offer invaluable insights into the intertwined histories of humans and the animals they domesticated.
Reference: Kevin G. Daly et al, Ancient genomics and the origin, dispersal, and development of domestic sheep, Science (2025). DOI: 10.1126/science.adn2094. www.science.org/doi/10.1126/science.adn2094