Deer (Capreolus capreolus)

Kingdom: Animalia

Phylum: Chordata

Class: Mammalia

Infraclass: Eutheria

Order: Artiodactyla

Suborder: Ruminantia

Infraorder: Pecora

Family: Cervidae

Deer are widely distributed, and hunted, with indigenous representatives in all continents except Antarctica and Australia, though Africa has only one native species, the Red Deer, confined to the Atlas Mountains in the northwest of the continent.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. Additionally, access to adjacent croplands may also benefit deer. However, adequate forest or brush cover must still be provided for populations to grow and thrive.Small species of brocket deer and pudús of Central and South America, and muntjacs of Asia generally occupy dense forests and are less often seen in open spaces, with the possible exception of the Indian Muntjac. There are also several species of deer that are highly specialized, and live almost exclusively in mountains, grasslands, swamps, and "wet" savannas, or riparian corridors surrounded by deserts. Some deer have a circumpolar distribution in both North America and Eurasia. Examples include the caribou that live in Arctic tundra and taiga (boreal forests) and moose that inhabit taiga and adjacent areas. Huemul Deer (taruca and Chilean Huemul) of South America's Andes fill an ecological niche of the ibex or Wild Goat, with the fawns behaving more like goat kids.The highest concentration of large deer species in temperate North America lies in the Canadian Rocky Mountain and Columbia Mountain Regions between Alberta and British Columbia where all five North American deer species (White-tailed deer, Mule deer, Caribou, Elk, and Moose) can be found. This region has several clusters of national parks including Mount Revelstoke National Park, Glacier National Park (Canada), Yoho National Park, and Kootenay National Park on the British Columbia side, and Banff National Park, Jasper National Park, and Glacier National Park (U.S.) on the Alberta and Montana sides. Mountain slope habitats vary from moist coniferous/mixed forested habitats to dry subalpine/pine forests with alpine meadows higher up. The foothills and river valleys between the mountain ranges provide a mosaic of cropland and deciduous parklands. The rare woodland caribou have the most restricted range living at higher altitudes in the subalpine meadows and alpine tundra areas of some of the mountain ranges. Elk and Mule Deer both migrate between the alpine meadows and lower coniferous forests and tend to be most common in this region. Elk also inhabit river valley bottomlands, which they share with White-tailed deer. The White-tailed deer have recently expanded their range within the foothills and river valley bottoms of the Canadian Rockies owing to conversion of land to cropland and the clearing of coniferous forests allowing more deciduous vegetation to grow up the mountain slopes. They also live in the aspen parklands north of Calgary and Edmonton, where they share habitat with the moose. The adjacent Great Plains grassland habitats are left to herds of Elk, American Bison, and pronghorn antelope.

Deer weights generally range from 30 to 250 kilograms (70 to 600 lb), though the Northern Pudu averages 10 kilograms (20 lb) and the Moose averages 431 kilograms (1,000 lb). They generally have lithe, compact bodies and long, powerful legs suited for rugged woodland terrain. Deer are also excellent jumpers and swimmers. Deer are ruminants, or cud-chewers, and have a four-chambered stomach. The teeth of deer are adapted to feeding on vegetation, and like other ruminants, they lack upper incisors, instead having a tough pad at the front of their upper jaw. Some deer, such as those on the island of Rùm,[3] do consume meat when it is available.[4] The Chinese water deer, Tufted deer and muntjac have enlarged upper canine teeth forming sharp tusks, while other species often lack upper canines altogether. The cheek teeth of deer have crescent ridges of enamel, which enable them to grind a wide variety of vegetation.[5] The dental formula for deer is: Upper: 0.0-1.3.3, lower: 3.1.3.3. Nearly all deer have a facial gland in front of each eye. The gland contains a strongly scented pheromone, used to mark its home range. Bucks of a wide range of species open these glands wide when angry or excited. All deer have a liver without a gallbladder. Deer also have a tapetum lucidum which gives them sufficiently good night vision. Nearly all cervids are so-called uniparental species: the fawns are cared for by the mother only. A doe generally has one or two fawns at a time (triplets, while not unknown, are uncommon). The gestation period is anywhere up to ten months for the European Roe Deer. Most fawns are born with their fur covered with white spots, though in many species they lose these spots by the end of their first winter. In the first twenty minutes of a fawn's life, the fawn begins to take its first steps. Its mother licks it clean until it is almost free of scent, so predators will not find it. Its mother leaves often, and the fawn does not like to be left behind. Sometimes its mother must gently push it down with her foot.[6] The fawn stays hidden in the grass for one week until it is strong enough to walk with its mother. The fawn and its mother stay together for about one year. A male usually never sees his mother again, but females sometimes come back with their own fawns and form small herds. Deer are selective feeders. They are usually browsers, and primarily feed on leaves. They have small, unspecialized stomachs by ruminant standards, and high nutrition requirements. Rather than attempt to digest vast quantities of low-grade, fibrous food as, for example, sheep and cattle do, deer select easily digestible shoots, young leaves, fresh grasses, soft twigs, fruit, fungi, and lichens.