AP BIOLOGY

Detailed explanation-1: -Fossils spanning a period of more than 50 million years show how the horse evolved. The oldest horse fossils show what the earliest horses were like. They were only 0.4 m tall, or about the size of a fox, and they had four long toes.

Detailed explanation-2: -When Sifrhippus sandae, the earliest known horse, first appeared in the forests of North America more than 50 million years ago, it would not have been mistaken for a Clydesdale. It weighed in at around 12 pounds–and it was destined to get much smaller over the ensuing millennia.

Detailed explanation-3: -The first equid was Hyracotherium, a small forest animal of the early Eocene. It looked nothing at all like a horse (10 – 20” hight). It resembled a dog with an arched back, short neck, short snout, short legs, and long tail.

Detailed explanation-4: -TRUE Fossils provide clear evidence that evolution has occurred. 2. TRUE Embryos of many different vertebrates look much more similar than the adult organisms.