Elephants have been domesticated for at least 4000 years.
However, today's elephant evolved from small pig-like
ancestor called Moeritherium about 50 million years ago. The
elephants are placed in the family Elephantidae of the order
Zoological name: There are two species of elephants: the
Asian elephant (Elephas maxim us) and the African elephant
(Loxodonta africana). The Asian elephant again has four subspecies: the Indian elephant (E.m.indicus), the Ceylon elephant (E.m.maximus), the Sumatran elephant
(E.m sumatranus) and the Malaysian elephant (M.m. hirsutus). The African elephant,
on the other hand, has two subspecies: the bush or savannah elephant (L.a .africana)
and the smaller forest elephant (L.a. Cyclotis).
Distribution: Elephants, the largest living terrestrial mammals, are distributed in African and certain Asian countries.
Habitat: They are found in savannah grasslands and forests. In India, they are found in the areas of tropical and some limited subtropical forests except in the dry scrub lands and saltwater mangrove forest. However, elephants prefer to live in undulating hilly terrains with thick forests. Some factors such as availability of water, food, environmental temperature, humidity, light, and predators play an important role in shifting their habitats.
Physical feature: The body weight varies from 4000-7000 kg depending upon the species involved. The adult height is recorded 10.8 ft or more. The height is reported to be approximately twice the circumference of forefoot. The body length ranges from 20 to 24.5 ft. The body surface is covered with sparse and coarse hair. The soles of the feet are covered with a soft and fatty cushion of white elastic fibres. The proboscis or pendant trunk is the elongation of the upper lip and nose. It enables the animal to feed and drink from the ground. The other functions of the trunk include breaking off branches, picking of leaves and shoot, feeding from trees and shrubs, drinking water and throwing dust. Another salient anatomical feature of an elephant is its tusks. They are actually modified and elongated upper incisor teeth. It is composed of ivory which is a mixture of dentine, cartilaginous material and salts. Tusks first appear at about 2-3 years of age and grow throughout life. However, they attain full growth in about 25 years of age. The average weight of a male tusk may be 60 kg. or more. The average length of a tusk may range from five to eight feet. The tusks are used for digging of roots, removing the bark of trees etc. Tusks also serve as a defensive weapon. The total number of teeth is 26 (I: 1/0; C: 0/0; PM: 3/3; M: 3/3). The premolar and molar teeth replace each other in succession throughout life. It is said that the first milk molar teeth appear at the age of two weeks and shed about two years of age. In this way, the second pairs shed at the age of six; third pairs at nine; the first adult teeth or the fourth pairs between twenty and twenty five year; the fifth pairs at sixty and the last pairs remain for the rest of the life. So, this is an important tool for estimation of age of an individual animal with great accuracy. Elephants have 20-21 pairs of ribs. Ears serve like a radiator of a car. Each elephant has a characteristic pattern of blood vessels in the ear. The ear cartilage of old animal becomes hard and the fringe of the ears becomes tom and ragged. The kidney is having five to seven lobes. Another salient anatomical feature is that the lungs are adhered to the chest wall by fibrous connective tissue resulting in the absence of pleural cavity. However, the pleural cavity is found in the young elephant. Elephants are non ruminants with a simple stomach. There is no gall bladder.