A deer is a ruminant mammal belonging to the family Cervidae. A number of broadly similar animals from related families within the order Artiodactyla (even-toed ungulates) are often also called deer. Male deer grow and shed new antlers each year, as opposed to antelope, which are in the same order and bear a superficial resemblance to deer physically, but are permanently horned.Depending on their species, male deer are called stags, harts, bucks or bulls, and females are called hinds, does or cows. Young deer are called fawns or calves. Deer live in a variety of biomes ranging from tundra to the tropical rainforest. While often associated with forests, many deer are ecotone species that live in transitional areas between forests and thickets (for cover) and prairie and savanna (open space). The majority of large deer species inhabit temperate mixed deciduous forest, mountain mixed coniferous forest, tropical seasonal/dry forest, and savanna habitats around the world. Clearing open areas within forests to some extent may actually benefit deer populations by exposing the understory and allowing the types of grasses, weeds, and herbs to grow that deer like to eat. However, adequate forest or brush cover must still be provided for populations to grow and thrive.