Life cycle
Elephants live in small family groups led by old females (cows). Where
food is plentiful, the groups join together. Most males (bulls) live in
bachelor herds apart from the cows. Males and females both possess two
glands that open between the eye and ear. Elephants of all ages and
sexes secrete a fluid called temporin out of this orifice. Males,
however, enter a “musth
period,” during which they secrete a fluid differing in viscosity from
the fluid secreted when they are not in musth. Serum testosterone
during musth is higher than in a nonmusth elephant, and the animal's
behaviour is erratic; they are uncontrollable (musth is Hindi
for “intoxicated”), sometimes even by their own handlers (mahouts).
Musth is the time for establishing reproductive hierarchy, which can
differ from the usual social hierarchy in that a male in musth outranks
nonmusth males. In the wild, males are usually at their prime physical
state during musth and ordinarily do most of the breeding.
Elephants
are able to assess the reproductive status of one another by using
their keen sense of smell. Inside the skull, elephants possess from
seven to nine nasal turbinals with specialized sensitive tissues for olfaction. (Humans have only three turbinals; dogs have five.) When a female is in estrus,
or when a male is in musth, an elephant apparently can detect airborne
hormones. Once “collected,” the information is then passed to the Jacobson's organ,
located on the roof of the mouth. This organ conveys the molecules to
the brain for analysis. Hormones are also sniffed directly from urine
and feces.Gestation is the longest of any mammal (18–22 months). The newborn elephant is about a metre (3.3 feet) tall and weighs about 100 kg (220 pounds). It suckles by using the mouth, not the trunk, at mammary glands located in the chest region. Weaning is a long process and sometimes continues until the mother can no longer tolerate the pokes of her offspring's emerging tusks. After weaning, many hours of each day are spent eating. An adult elephant consumes about 100 kg of food and 100 litres (26 gallons) of water per day; these amounts can double for a hungry and thirsty individual. Such consumption makes elephants an important ecological factor; they substantially affect and even alter the ecosystems they live in.
Elephants migrate seasonally according to the availability of food and water. Memory plays an important role during this time, as they remember locations of water supplies along migration routes. Intelligence has also been observed in conjunction with memory. One elephant, using its tusks and trunk, stripped bark from a nearby tree and chewed it until it made a large ball, then plugged a waterhole it had previously dug and covered the plug with sand. Subsequently, the elephant was seen to uncover the sand, unplug the hole, and drink—a behaviour that could be interpreted as tool-making.
Although unable to jump or gallop, elephants can
reach a top speed of 40 km (25 miles) per hour. Their feet are well
adapted to carrying their great weight. The heel is partially elevated,
and below it is a thick fatty, fibrous wedge of tissue protected by
thick skin. It is not easy for elephants to lie down and get up; they
sleep lying down for three to four hours during the night. While
standing, elephants doze for short periods but do not sleep deeply.
Elephants can live to 80 years of age or more in captivity but live to
only about 60 in the wild. Evidence does not substantiate the existence
of so-called “elephant graveyards,” where elephants supposedly gather
to die.
Importance to man
For many centuries the Asian elephant has been important as a
ceremonial and draft animal. Technically, elephants have not been
domesticated, for they have not been subjected to selective breeding
for “improvement” of traits desired by humans, as has been the practice
with cattle, horses, and dogs. Historical records of tamed Asian
elephants date to the Indus civilization of the 3rd millennium BC. At Mohenjo-Daro and Harappa, Pakistan, soapstone carvings depict elephants with cloth on their backs, which indicates use by humans. Mahouts
and oozies (elephant trainers in India and Myanmar, respectively) are
skilled people who remain in direct contact with the animals for many
years. The handlers take care of all the elephants' needs, and the bond
between man and beast becomes very strong. Hastividyarama,
an age-old handbook for elephant tamers, spells out prescribed training
procedures in detail and is still used today in some parts of Asia.
Commanded by its mahout, the elephant was once basic to Southeast Asian
logging operations. It remains a symbol of power and pageantry but has
been largely supplanted by machinery. At the beginning of the 21st
century, Thailand and Myanmar each had about 5,000 captive elephants
employed in traditional roles intermingled with modern use as tourist
attractions.
The most famous historical event using elephants in war was that of Hannibal, the young commander of the Carthaginians who crossed the Alps from Spain into Italy. He left Cartagena, Spain, in 218 BC
with 37 elephants—36 African forest elephants and one Asian—each under
its own well-trained mahout. The Asian, Hannibal's personal elephant
named Surus (meaning “Syrian”), was the only one that survived to reach
Italy.African elephants were also tamed during the19th century, in what was the Belgian Congo. Training of these forest elephants was initiated by King Leopold II of Belgium and was conducted by Indian mahouts with Asian elephants. African elephants are now used mainly for transporting tourists in Garamba National Park, where they are valuable in providing revenue to sustain its activities.
Conservation
At the beginning of the 21st century, fewer than 50,000 Asian elephants
remained in the wild. Threatened by habitat loss and poaching, Asian
and African elephants are listed as endangered species.
From 1979 to 1989 the number of African elephants in the wild was
reduced by more than half, from 1,300,000 to 600,000, owing in part to
commercial demand for ivory. However, in some parts of Africa elephants
are abundant, and culling is practiced in some reserves to prevent
habitat destruction. A nine-year ban on the ivory
trade was lifted in 1997, and Botswana, Namibia, and Zimbabwe were
allowed to sell limited stocks of ivory from government warehouses to
Japan. In 2000 South Africa joined the three southern African nations
in selling limited amounts of ivory from existing stocks.
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