(05.01 mc) horses are mammals with a single hoof on each foot that has evolved to bear the full force of the horse's weight. other mammals have many toes that support the animals' weight. horses and many-toed mammals share a common ancestor since horses are also mammals. fossil evidence of intermediate species has been found that shows how horses evolved. compare the limbs and body sizes of the modern horse and its ancestors shown in the diagram. five animals resembling horses are shown: equus (modern horse), a very large animal with one toe on each foot in the form of a hoof; pliohippus, slightly smaller than a modern horse with a shorter mane and tail hair and one hoof on each foot; merychippus, similar in size to pliohippus with three toes; hyracortherium, a tiny animal with four toes; mesohippus, a small animal with three toes on each foot. the single or middle toe on each foot of all the animals is the largest toe. which of the following answer choices lists the ancestors of the modern horse, in order, from the oldest that lived 60 million years ago to the most recent that lived 7 million years ago? (1 point) hyracotherium, mesohippus, merychippus, pliohippus, because over time, the number of toes decreased and body size increased. pliohippus, mesohippus, merychippus, hyracotherium, because over time, the number of toes increased and body size decreased. hyracotherium, merychippus, mesohippus, pliohippus, because over time, the number of toes decreased and body size increased. pliohippus, merychippus, mesohippus, hyracotherium, because over time, the number of toes increased and body size decreased.