The First Horses
37 - 32 Million Years Ago
During this time, some of the early horses migrated across a land bridge between Europe and North America. As the temperature and the climate changed, conifers began to outnumber deciduous trees. The forest thinned and grass became more prevalent. Mesohippus was larger than Hyracotherium, its teeth had further evolved, and it had three toes on its front legs. It was better suited to running fast to escape the enemies that pursued. Because the swamp had given way to soft ground, Mesohippus no longer needed his toes as much has Hyracotherium did. The lateral supporting toes decreased in size while the middle toe strengthened. The toes ended in little hooves but still had a pad behind them. This genus lived about 37 to 32 million years ago.