Rhonda Corcoran, age 10, of Cumberland, Maine, for her question:

WHEN WAS THE FIRST HORSE BORN?

Scientists say that the earliest ancestor of the horse was a small animal about 10 to 20 inches high called the eohippus, or dawn horse. It lived about 55 million years ago in what is now North America and Europe.

The tiny prehistoric horses had arched backs and snout like noses. They looked more like racing dogs than like the long faced modern horse. They had four toes on their front feet and three toes on their hind feet. Each toe ended in a separate, small hoof. Large, tough pads, similar to those on a dog's foot, kept the toes off the ground. These pads carried the animal's weight.

The next ancestor to the modern horse lived about 35 million years ago. He was called a mesohippus, or middle horse.