Horse Color Genetics in the Pleistocene Era
The oldest Equus Caballus fossils genotyped thus far are from the Late Pleistocene Era (time period prior to 5000 BC). Bone samples containing intact DNA were excavated from five main archeological sites. The DNA was then used to compare the coat color genes present in horses from the Pleistocene Era to the coat color genes present in the DNA of current-day horses.
All genotyped fossils encoded for the same phenotype in both European and North Asian horses: Bay. This indicates that the horse population during the Late Pleistocene Era was composed mostly (if not entirely) of the Bay coat color.