Three recent studies led by Dr. Orlando have significantly advanced the field. The first, published in Nature (July 2024), presents the largest whole-genome time series of horses to date, spanning 50,000 years across Eurasia and including nearly half of all Asian genomes. This dataset provides a critical comparative framework for Bronze and Iron Age horses in Mongolia and China and introduces a novel method to infer past generation times from ancient genomes, offering insights into breeding intensity and herd management. Results revealed three major periods of accelerated generation times: in the past two centuries with the rise of modern breeds; around 2200–2700 BCE, when the DOM2 lineage emerged in the Don-Volga basin, ancestor of all modern domestic horses; and around 3500 BCE, marking the Botai domestication in Kazakhstan. This confirms horse domestication began in Central Asia ca. 3500 BCE, though this lineage was later abandoned and survives today only as the Przewalski’s horse. The method is broadly applicable and may reshape demographic models of other species, including humans. The second study, published in Science (May 2025), reports the first genomes of an extinct Ice Age horse lineage native to the Russian Far East and northeastern China, which likely contributed to local gene pools before domestic horses arrived. While the genetic results refine regional histories, the major breakthrough lies in its collaborative framework, integrating Indigenous knowledge and perspectives from Lakota, Okanagan, Blackfoot, and Inupiak communities, who emphasized the “Medicine Man Trail”—a cultural and ecological corridor linking North America and Mongolia, highly relevant to Horsepower. The third study, published by Science in August 2025, identifies a novel genetic marker enabling secure identification of domestic horses, even from fragmentary remains. Crucially, this marker shows strong selection from the onset of domestication around 2200 BCE, pinpointing its role in the rise of modern domestic horses—a transformative development that made horses the central drivers of mobility, warfare, and exchange across Eurasia until the advent of motor engines in the 19th century CE. Another study was submitted to Science in April 2026, and is currently under evaluation. It describes the most comprehensive ancient and modern genome panel assembled to date, revealing the deep historical roots of those genetic ancestries shaping modern horse populations worldwide. It also establishes the foundation for statistical imputation of genotypes/haplotypes, considerably enhancing the predictive power of ancient DNA analyses in horses. This article shapes the nature of the genetic analyses to be performed in the second half of the Horsepower project. With the excavations in Mongolia, we have now assembled a unique series of human skeletons from the first pastoralists herding cattle and sheep/goat (Afanas'evo, 2900-2600 BCE), to the Middle Bronze Age (Mönkhkhairkhan 1800-1500 BCE) to the Late Bronze Age (Sagsai, Khirgisuurs 1500-1000 BCE) that allows for studying changes in lifestyle within pastoralists communities and investigate when riding became habitual among pastoralists. Since this is critical for understanding the integration of horses into pastoral communities in Eastern Eurasia, we will exand the anthropological studies through BoCAS at Bonn University.
