The female is called a ewe, the male is called a ram, and the young are called lambs. Most of the year, these sheep gather in large segregated herds, some consisting of all rams, and others containing ewes plus their lambs. Bighorn sheep are closely related to goats. They have an average life span of about 10 to 15 years in the wild. When they die, is it usually during the winter due to the cold, predators, lack of food, or disease.

Rams (adult males) engage in head-to-head combat to determine their rank and win females. These head-jarring battles can last for over a day.

Anatomy: Bighorn sheep are sure-footed animals who have a rough pad on the bottom of their two-toed, spread-out hooves; they move well on rough, uneven ground. They have a furry light-brown coat with hollow hairs that protect them from temperature extremes; there is often a white patch on the rump and muzzle. The winter coat is lighter in color than the summer coat. Bighorn sheep are about 32 to 40 inches (81-100 cm) tall at the shoulder and are 50 to 62 inches (1.3-1.6 m) long (including the tail).

The curving horns are light brown; they continue to grow throughout the sheep's lifetime and do not drop off. Both males and females have horns, but males have much bigger horns. The horns are made of keratin, the same material our fingernails are made of; growth rings (called annuli) on the horns tell us how old a sheep is.

Diet: Bighorn sheep are herbivores (plant-eaters) who spend most of the day grazing. They eat grass, leaves, herbs, twigs, and shoots. Sheep swallow their food without chewing it much. Later, they regurgitate the food (then called a cud) and chew it thoroughly before swallowing it again.

Predators: Wolves, mountain lions, bears, and humans are predators of Bighorn sheep.

Classification: Class Mammalia (mammals), order Artiodactyla (even-toed hoofed mammals), family Bovidae (antelope, cattle, goats, sheep), subfamily Caprinae, genus Ovis, species O. canadensis.