Evolution of the horse: Propalaeotherium

Propalaeotherium, the nervous ancestor of the horse, forages for forest food.

Fossilised pregnant Propalaeotherium remains show that the females bore a single foal at a time. One of the earliest horses, these little forest animals had four small hooves on their front feet and three on the back. They walked on the pads of their feet, like cats and dogs. There were two species, one slightly larger than the other. More than 35 beautifully preserved specimens of the two species are known from the Messel shales, and they are also found at the nearby site of Geiseltal in Germany.

Source:  BBC Nature Walking With Beasts