Continuing along the theme of evolution, from where did the domestic horse arise? We all know that horses afforded humans with the first opportunity to spread genes, diseases, and culture much faster than humans could do on foot. Horses remained important to transportation, even after the advent of steam locomotion, and until the widespread use of motor vehicles. Horses also revolutionized warfare, pulling chariots at full speed in the Bronze Age, providing the foundation for mounted battle in the early Iron Age, and facilitating the spread of cavalry during Antiquity. Horses remain essential today, to the economy of developing countries, and to the leisure (racing, dressage, polo) industries of developed countries.
The earliest archaeological evidence of horse milking, harnessing, and corralling is found in the ~5,500-year-old culture of the Central Asian Steppes. The genetic origin of modern domestication of horses has remained unclear — with suggested origins in the Pontic-Caspian steppes, Anatolia, and Iberia. Irrespective of the origins of domestication, the horse genome is known to have been reshaped significantly within the last ~2,300 years. Authors [bazillions of them; see attached article] present the largest “DNA time series” for a non-human organism to date, including genome-scale data from 149 ancient animals and 129 ancient genomes, 87 of which are new. This extensive dataset allows us to assess the modern legacy of past equestrian civilizations.
Authors find that two extinct horse lineages existed during early domestication — one at the far western range (Iberia), the other at the far eastern range (Siberia) of Eurasia. None of these, however, contributed significantly to modern diversity. Authors show that the influence of Persian-related horse lineages increased, following the Islamic conquests in Europe and Asia. Multiple alleles associated with elite-racing — including those of the MSTN ‘‘speed gene’’ (encoding myostatin) — rose in allelic frequency only within the last 1000 years. Lastly, development of modern horse breeding is shown to have had a more dramatic impact on genetic diversity than previous millennia of human diversity.
Cell 30 May 2o19; 177, 1419–1435