A species of small, free-ranging horse from the Russian steppe, it is uncertain whether tarpans were wild or feral creatures, hence their ferus taxonomy. They were first described by the German botanist Samuel Gottlieb Gmelin in 1771 and the last tarpan is thought to have died in captivity in 1909. They varied in color, resembling ancient depictions found in cave paintings made in Europe during the Pleistocene epoch, and some may have carried the dun gene, sporting a blue grullo coat. They were hunted to extinction. Many domesticated horses bear phenotypic traits of the tarpan.