This project will be used by a Postdoctoral Researcher in the Wildlife Palaeogenomics Group (led by Professor Love Dalén) at the Centre for Palaeogenetics, Stockholm University. It is funded by a Swedish Research Council VR Rådsprofessor grant and is expected to run for a minimum of 1.5 years. The aim of the project is to investigate the evolutionary history of horses throughout the Pleistocene using ancient DNA. While modern horses represent only a fraction of the once-rich equid diversity that roamed across the Northern Hemisphere and South America, ancient DNA from bone samples spanning the past one million years offers a powerful means of reconstructing this lost diversity. Key research areas of this project include phylogenetics, genetic diversity, admixture, and demographic history, particularly in relation to past climatic and environmental changes. One focus of the project is Denisova Cave, which is located in the Altai Mountains of Siberia and is a site renowned for its paleontological findings of archaic hominin groups (Denisovans and Neanderthals). Our research group has begun to examine the genomes other faunal remains from this site. For this project, we have obtained over 200 horse bone fragments from Denisova Cave. Our preliminary analyses have identified and recovered mitogenomes from extinct equid lineages. Continued screening of samples and deep sequencing of those that are well-preserved will shed light on the evolutionary dynamics of equids in this region during the Pleistocene. The project has also obtained material from Casa del Diablo, a high-altitude cave site in the Peruvian Andes. Although DNA preservation in warmer regions, such as South America, are typically poor, the cold and dry conditions of this cave have enabled excellent sample preservation. This is evident in the recent recovery of a 14,000-year-old vulture genome from the site. The project has nine horse bones from this Casa del Diablo cave, with preliminary mitogenome analyses identifying them to the species-level. Deeper sequencing to obtain nuclear genomes will enable more fine-scale assessments of their evolutionary history in this high-altitude environment. Additional samples for this project have been collected from sites in Yukon, Canada. This includes incredibly old material, such as a ~700,000 year-old horse sample from Paradise Hill (Klondike, Canada).