The Asian elephant, Elephas maximus, and the African elephant, Loxodontia africana are the only elephant species remaining from a once diverse group, the Proboscidea. The Asian elephant can be distinguished from the African form by its smaller size, smaller ears, convexly curved back, flattened forehead, and the presence of one instead of two lips on the distal end of the trunk.

The elephant skull is disproportionately large compared to the size of its brain. The oversized skull is necessary to support the large and complex musculature used to manipulate the trunk. The presence of numerous cavities and air cells within the skull, however, considerably lighten the overall weight.

The dentition of elephants is unique. The canine teeth are lost so that only the incisors, premolars, and molars are retained. The pattern of replacement of the molariform teeth resembles a conveyor belt with teeth emerging at the back of the mouth and then being pushed forward. Mastication is performed using only one molariform tooth per quadrant. As one tooth is worn down, another pushes forward to take its place and the worn tooth is spit out. When the last molar is worn down, the elephant becomes highly susceptible to starvation.