It is a ruminant, eating its food in two stages and having an even number of toes on each hoof, like camels, goats and cattle.
Similarly, a stag that does not grow antlers is a hummel.
The antlers are testosterone-driven and as the stag's testosterone levels drop in the autumn, the velvet is shed and the antlers stop growing.
The Caspian red deer's winter coat is greyer and has a larger and more distinguished light rump-patch (like wapiti and some central Asian red deer) compared to the Western European red deer, which has more of a greyish-brown coat with a darker yellowish rump patch in the winter.
By the time summer begins, the heavy winter coat has been shed; the animals are known to rub against trees and other objects to help remove hair from their bodies.
The male deer of the British Isles and Norway tend to have the thickest and most noticeable manes. A soft covering known as velvet helps to protect newly forming antlers in the spring.