There is a great deal of physical diversity within the family Cervidae. Moose, the largest extant member of the family, can reach up to 1800 lbs and the smallest, northern pudu, reach a maximum size of roughly 20 lbs. Typically members have compact torsos and very powerful elongated legs that are well suited for woody or rocky terrain. With the exception of Chinese water deer, all male cervids have deciduous antlers and caribou are the only species in which both males and females have antlers. Deer are primarily browsers (foraging on broad leaf plant material), and their low- (brachydont) to medium-crowned (mesodont) selenodont cheek teeth are highly specialized for browsing. Cervids lack upper incisors and instead have a hard palate. The anterior portion of the palate is covered with a hardened tissue against which the lower incisors and canines occlude. They have a 0/3, 0-1/1, 3/3, 3/3 dental formula. Other notable features of cervids include the lack of a sagittal crest and the presence of a postorbital bar.
Antlers grow from pedicels, boney supporting structures that grow on the lateral regions of the frontal bones. In temperate-zone cervids, antlers begin growing in the spring as skin-covered projections from the pedicels. The dermal covering, or "velvet," is rich in blood vessels and nerves. When antlers reach full size, the velvet dies and is rubbed off as the animal thrashes its antlers against vegetation. Antlers are used during male-male competition for mates during breeding season, and are shed soon afterwards. Typically, only males bear antlers however, both genders bear antlers in caribou. Antlers vary from simple spikes, such as those in munjacs, to enormous, complexly branched structures, such as those in moose. Antler structure changes depending on species and the age of the individual bearing them. Males of the genus Muntiacuc have both antlers and long, fang-like upper canines that are used in social displays. Although Chinese water deer are the only species without antlers, they have elongated upper canines that are used to attract mates. Antlers typically emerge at one year of age.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: male larger; sexes shaped differently; ornamentation