The evolutionary lineage of the horse is among the best-documented in all paleontology. The history of the horse family, Equidae, began during the Eocene Epoch, which lasted from about 55.8 ... Read More

The ancestry of the horse family is obscure; small, multiple-toed, primitive representatives, known as Hyracotherium (or Eohippus) appeared simultaneously in Europe and America near the beginning of the Cenozoic era ... Read More

Apart from a couple of bothersome side branches, horse evolution presents a neat, orderly picture of natural selection in action. The basic story line goes like this: as the woodlands ... Read More

This small dog-sized animal is the oldest found horse ancestor that lived about 55 million years ago. It had a primitive short face, with eye sockets in the middle ... Read More

Imagine a world in which horses of all colors, shapes, and sizes roamed the world, some barely larger than a small dog. That world no longer exists--but once it was ... Read More

In the 1870's, the paleontologist O.C. Marsh published a description of newly discovered horse fossils from North America. At the time, very few transitional fossils were known, apart from Archeopteryx. ... Read More