The most defining feature of these deer is their large, mule-like ears.
They are brown to gray color, with lighter coloration around their rumps and faces than the rest of their bodies. The tail is white with a black tip.
Mule deer adults are generally less than one-third the weight of adult elk weighing a maximum of around 200lbs (90kg) and standing 31-42 inches (80-106cm) tall at the shoulder.
Mule deer are found throughout western North America- from northern Mexico to Alaska, and as far east as the Great Plains.
They are some of the most versatile animals in Grand Canyon National Park, and are found in all habitats in the park- ranging from the forests of the Rims to desert scrub on the Tonto Plateau to the riparian habitat along the Colorado River.
Males (bucks) grow a new, larger pair of antlers each year which they shed in the spring.
Females (does) give birth to fawns in late spring/early summer.
Mule deer are herbivores with a wide diet- they eat grasses, flowering plants, shrubs, nuts, and berries.
They are the preferred prey of mountain lions. Mule deer have excellent hearing and eyesight to help them avoid predators.
They are adapted to living in a dry environment. During summer, they are only active at night or early morning to avoid the heat. The large ears on mule deer are known to radiate heat away from the deer's body, helping to keep it cool.