DESCRIPTION:
The adult male is much larger than
the adult female. Head and body length including trunk: 19-24 feet. Shoulder
height: 10-13 feet.
Weight: 5.5 - 7 tons. Tail: 4 feet.
Brownish gray skin has folds and may be one inch thick in places. The African
Elephant has a marked dip between its fore and hindquarters giving a concave
curvature to its back. Ears are large and fan-like. The trunk has two prehensile
protrusions at the tip. Large tusks are present in both sexes. Elephants
are digitigrade with pads of fibrous tissue to cushion toe bones.
GEOGRAPHICAL RANGE AND HABITAT:
Natural home range is 500 miles; migratory patterns are
taught from one generation to the next. Now they are mostly restricted
to parks and preserves. Habitat formerly was area south of the Sahara;
agricultural expansion has severely reduced it. Highly adaptable, elephants
can survive in forest, bush or savanna.
DIET:
Elephants have an inefficient digestive system and digest
only about 40 per cent of what they eat. They eat enormously. Estimates
in the wild range from 100-1000 pounds of vegetation per day (a 16 hour
period). Zoo elephants are estimated to eat approximately 50 pounds of
food per ton of elephant per day. Working elephants need 300 to 600 pounds
of food per day. The wild elephant is a destructive eater, uprooting and
scattering as much as is eaten, often breaking down whole trees. Elephants
eat almost anything green, but green grass, shoots and buds of trees and
shrubs are preferred. Farms are often raided for fruits and vegetables
of all types.
Average daily consumption of water for full-grown animals
is between 30 and 50 gallons.
LIFE CYCLE/SOCIAL STRUCTURE:
Elephants live in a complex matriarchal society normally
composed of 8 to 15 related members and led by a dominant cow. Three or
four generations of cows and calves spend their entire lives together with
the exception of males, who leave the group at puberty.
Groups of related families stay in fairly close range
of each other and communicate often; these are called kin groups. In times
of danger, kin groups will mass and form clans of 200 or more. Ongoing
studies at Amboseli Research Center in Kenya indicate a complex bull dominance
structure which determines mating success as well as every day life. Another
primary mating factor is musth, a periodic hormonal cycle seen in both
species. Physical manifestations in males include heavy secretions from
temporal glands, high blood testosterone levels, urine dribbling (marking)
and aggression. Cows seem to prefer a musth bull, but can successfully
breed whether the bull is in musth or not. The cow's oestrus cycle is roughly
a monthly one and lasts 2-6 days. Gestation is approximately 22 months.
The birth is usually a single one; twins are born only 1.35% of the time.
Birth weight is 175 to 250 pounds. Mother is often assisted by another
cow during birthing. The calf can stand shakily and nurse (with mouth,
not trunk) a few hours after birth. Mammary glands are located between
the front legs. Calves will nurse well into their third year and are very
dependent on their mothers for eight to ten years. Adolescence at 12 to
14 years of age. Most physical growth is reached at 20, but growth continues
throughout life. Top mental ability is at age 30 to 45. Death comes at
65 to 70 years of age when the last set of teeth wear out.
SPECIAL ADAPTATIONS:
The majority of the skull is honeycombed with sinuses
to minimize weight. Tusks are elongated second upper incisors and grow
throughout the lifetime. They are used for food gathering and carrying,
as well as weapons. Molars make up other dental equipment; six consecutive
sets of two upper and two lower molars are produced throughout life. The
first set has three enamel layers, increasing to ten layers in the sixth
set. The trunk is an elongation of the nose and upper lip; in adults it
contains 40,000 to 100,000 muscles. Literally the animal's lifeline, it
is used for eating, drinking, dust and water bathing, as well as communication.
The sense of smell is highly sophisticated; they are believed to locate
underground water by smelling the earth above. Vision is poor. Long lashes
and nictitating lids protect the eyes from dust. Hearing is acute. Recent
studies establish the use of infrasound (tones lower than humans can hear)
for long-range communication. Ears are also used to control body temperature;
blood circulating through the large vessels in the ears is cooled by flapping.
INTERPRETIVE INFORMATION:
Skin is extremely sensitive to sunburn and insect bites;
they roll in dust and mud and throw dust on their backs to help protect
their skin.
Elephants have the largest brain size versus body weight
other than man. New intelligence data: most mammals, excluding primates,
are born with a brain weight of 90% of adult weight. A human brain at birth
is 26% of adult weight, and the elephant's is 35% of adult weight. These
statistics are used to distinguish instinctive from learned behavior, and
are examples of higher intelligence.
STATUS IN WILD:
Endangered because of loss of habitat and because of
poaching for ivory.
