Hyracotherium

Also known as Eohippus, or "Dawn Horse," Hyracotherium is the oldest known horse. Both terms are names of genera. The name Hyracotherium actually means "Hyrax-like" because when it was initially discovered by Robert Owen in 1841 he believed it was an early Hyrax. A few decades after that, Othniel C. Marsh determined that the fossils in fact belonged to an early horse, but due to naming rules the first name became the official one, even though Eohippus is probably more appropriate. Both names are still heard today.

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Hyracotherium lived in the Early Eocene, approximately 60-45 million years ago. It was a very small mammal that measured only about two feet long and stood 12-14 inches at the shoulder. They lived in woodland areas in the Northern Hemisphere.

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Hyracotherium did not have the hooves of modern horses. Instead, they had toes! Four toes were found on the front feet, while the back feet had only three. They also had pads on their feet similar to those of modern dogs. Hyracotherium had 44 low crowned teeth, including six incisors and two canines, and most likely browsed on leaves, fruits, and plant shoots. Thought we don't actually known what color Hyracotherium was, they are often drawn as having dark coats with light spots, which would help to camouflage them in a forest habitat.

Hyracotherium is only the first of a long line of early horses that gradually evolved into the animals we have today. There are even some scientists who believe that Hyracotherium was the ancestor to not just horses, but to many other modern mammals as well, including Rhinos and Tapirs.