Vertebrate Zoology: Textbook - T. A. Dauda 2014

Multicellular Animals
Infraclass Eutheria, or Placental Mammals
Order Proboscidea

The order Proboscidea comprises the largest living land mammals, whose most distinctive feature is The Development of a trunk (Fig. 64). The trunk is a musculocutaneous organ formed by the fusion of a greatly elongated Nose and upper lip. Representatives of this order possess a massive, barrel-shaped body, supported by high, pillar-like, five-toed feet tipped with small hooves. The HEAD bears small eyes and large ears, while the tail is short. The Skin is thick and nearly hairless. The upper incisors are greatly enlarged and protrude from the Mouth as tusks, and canines are absent. The order includes two extant species: the African elephant and the Asian elephant.

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Fig. 64 Elephants:

1 — African; 2 — Asian.

The African elephant is distributed throughout tropical Africa. Males average up to 3.5 m in height with a mass of about 5 tonnes, whereas females are smaller, weighing up to 3 tonnes. Tusks are present in both sexes. The ears are large and drooping. These elephants are difficult to tame and remain relatively numerous.

Asian elephants are somewhat smaller than African elephants, reaching heights of up to 3 m. Their ears are triangular and folded backward, and tusks develop only in males. They are easily tamed, though they rarely breed in captivity. In the wild, Asian elephants are fewer in number than their African counterparts.

Elephants are gregarious animals living in herds. A herd is typically led by an old, experienced female, and only during periods of conflict does a male assume leadership. Elephants feed on plant matter early in the morning or at night. A female gives birth to a single, sighted calf weighing about 100 kg, which stands up and begins to suckle almost immediately after birth. It remains under maternal care for up to 5–6 years.

Sexual maturity is reached at approximately 16 years of age, but full physical maturity is attained by 25. Elephants live for up to 70 years. Domesticated individuals are employed in heavy labor, such as logging and transporting loads. As a rule, they do not breed in captivity, with only a few recorded instances of offspring born in zoos, including the Moscow Zoo.

Closely related to the Asian elephant is the extinct mammoth, which formerly inhabited the territory of the modern tundra. Its tusks and skeletal remains are frequently discovered within layers of permafrost.