An ungulate is any animal with hooves. It groups together some of the most familiar large mammals: horses, deer, pigs, cattle, sheep, goats, rhinos, and hippos are all ungulates.

Scientists divide ungulates into groups based on their hooves. Odd-toed ungulates include horses and rhinos, which have an odd number of toes on each foot (horses have one big hoof, rhinos have three). Even-toed ungulates include deer, cattle, pigs, and giraffes, which have an even number of toes, usually two or four. Even-toed ungulates often have split hooves, which you can see clearly on a cow or deer.

Hooves are incredibly useful adaptations. They're made of the same tough material as your fingernails, but much thicker and harder. This allows ungulates to run fast across rocky ground without injury. A wild mustang can gallop over desert rocks that would hurt your feet even through shoes. Hooves also help animals like mountain goats grip steep, dangerous cliffs.

Most ungulates are herbivores that graze on grass or browse on leaves, though pigs will eat almost anything. Many ungulates live in herds for protection against predators. When you see a group of zebras or a herd of bison, you're watching ungulates using their hooves to roam vast distances in search of food and water.