Hyracotherium

The oldest ancestor of the horse lived about 50 million years ago [personally, I do not believe the Earth is that old], and is alternately known as Eohippus (literally “dawn horse”) or Hyracotherium.  The first fossils of this creature – which had hoofed, padded toes and was approximately the size of a fox – were discovered by Richard Owen in 1841. Despite the vast differences in appearance between Hyracotherium and today’s horse, these pre-modern animals were herbivores and exhibited horse-like grooves on their molars.