Question

compare the fossils of horse ancestors with the structures of a modern horse.
evolution of horses
according to the fossil record, which species in the horses ancestry was likely the first to run on three toes?
a. pliohippus
b. merychippus
c. hyracotherium
d. mesohippus

Explanation:

Based on the fossil record and the evolutionary tree of horses, Merychippus is identified as the species likely to be the first to run on three toes. This conclusion is drawn from the anatomical structures and evolutionary progression depicted in the fossil evidence.

Answer:

B. Merychippus