A large deer adapted for arctic conditions which lives in huge herds. Now greatly reduced in numbers, and most herds are domesticated. Both males and females have antlers.

Life span
Up to 13, though on average only 4.5 years.

Statistics
100 - 130cm at the shoulder (males slightly larger than females).

Physical description
A large deer with a shaggy brown (summer) or grey (winter) coat. White rump and tail and a paler chest and belly. Both sexes have branching antlers, and males have a white mane during the rut. No naked patch on the muzzle. The tendons make a clicking noise in their feet as they walk.

Distribution
Once found throughout the northern latitudes but after extensive hunting they're only found in herd in Alaska, Canada, Scandinavia and Russia.

Habitat
Open tundra.

Diet
Any vegetation, including lichens and twigs.

Behaviour
Reindeer are adapted for living in the harsh northern areas, browsing around the woodland edges. They live in herds of 10-1000 animals, although they can form large herds of up to 200,000. They have poor eyesight and locate food using their keen sense of smell. Some migrate to the arctic plains for the summer. Many European herds are domesticated.

Reproduction
Mating occurs in October, when males fight to control small harems of 5-15 females. After a gestation of 227-229 days, a single calf is born, which is able to stand almost immediately and is a fast runner at one day old. Weaning begins at one month, but the youngster nurses occasionally until winter. Sexual maturity is reached at 29-41 days.

Conservation status
Not threatened.

History
The first artiodactyls (also called the 'even-toed ungulates') were present in the Eocene forests. The deer are probably descended from small animals like the chevrotains which browse and eat fallen fruit in forests. Like the chevrotains, deer use fermentation in their gut to digest plant material more efficiently - called rumination. As the forests began to open up in the Oligocene, ancestors of deer grew larger and browsed on the vegetation or grazed the new grass. They probably also formed herds for safety against predators. In the Miocene, the first horned deer appeared, with the males having horns to fight rather than using their canine teeth (as the musk deer and a few others still do).