By the Oligocene Epoch some horses were becoming larger, 
able to run swiftly through open woodlands. There were no 
wide-open grassy plains as yet - grasses were only just 
beginning to evolve. Miohippuslived from 30 to less than 
25 million years ago and had three toes per foot, all of 
which touched the ground. However, the middle toe was 
larger than the other two and bore most of the weight .
Miohippuswas about the size of today's sheep, standing some 
60cml24in at the shoulder, and had a 
longer, dished snout, . alonger neck and longer legsthat earlier horses. It lived at the Same time as another horse genus, 
Mesohippus, with probably the former giving rise to 
further, larger types of horses.