Horse

All Shapes and Sizes: Horses come in all shapes, colors and sizes. The equidae family describes your typical barnyard horse, but also includes asses, onagers and zebras.

A Horse is a Horse: According to Animal, in a list compiled by the Smithsonian Institution, what makes a horse a horse is its "deep chest, a mane on the neck, tufted or long-haired, tail, a solid hoof on each foot, thickened skin (called chestnuts) on the inside of the front legs above the knee, and mobile lips and nostrils." Horses also possess great endurance and speed. The fastest equidae is the onager, an Asian wild ass that can clock speeds in excess of 40 mph.

Gorging on Greens: Horses are vegetarian. They get most of their nutrients from grasses and their teeth are specially designed for grazing. A 1,000-pound horse typically will ingest between 15 and 25 pounds of food per day. The horse's digestive track is equipped to handle this large amount of roughage. Its stomach is small, but the intestines are very long, allowing the constant stream of nutrients to be easily digested.

Wild No More?: Where once wild horses galloped across open plains, they are endangered today due to habitat loss.

Wild, Wild Horses: There's a difference between true wild horses and feral horses. True wild horses, like the Przewalski's horse, were never domesticated; feral horses, like mustangs, are descended from domestic stock.