Elephants
Elephantidae (the elephants) is a family of pachyderm, and the
only remaining family in the order Proboscidea. Elephantidae has
three living species: the African Bush Elephant and the African
Forest Elephant (which were collectively known as the African Elephant)
and the Asian Elephant (formerly known as the Indian Elephant).
Other species have become extinct since the last ice age, which
ended about 10,000 years ago.
Elephants are mammals, and the largest land animals alive today.
The elephant's gestation period is 22 months, the longest of any
land animal. At birth it is common for an elephant calf to weigh
120 kg (265 lb). An elephant may live as long as 70 years, sometimes
longer if various bone diseases can be caught early. The largest
elephant ever recorded was shot in Angola in 1974. It was male and
weighed 12,000 kilograms (26,400 lb). The smallest elephants, about
the size of a calf or a large pig, were a pre-historic variant that
lived on the island of Crete until 5000 BC, possibly 3000 BC. Their
scattered skulls, featuring a single large trunk-hole at the front,
perhaps formed the basis of belief in existence of cyclops, one-eyed
giants featured in Homer's Odyssey.
Recent findings of animal remains in central China show Prehistoric
humans ate elephants. The elephant is now a protected animal, and
keeping one as a pet is prohibited around the world.
It has long been known that the African and Asian elephants are
separate species. African elephants tend to be larger than the Asian
species (up to 4 m high and 7500 kg) and have bigger ears. Male
and female African elephants have long tusks, while male and female
Asian Elephants have shorter tusks, with tusks in females being
almost non-existent. African elephants have a dipped back, smooth
forehead and two "fingers" at the tip of their trunks,
as compared with the Asian species which have an arched back, two
humps on the forehead and have only one "finger" at the
tip of their trunks.
There are two populations of African elephants, Savannah and Forest,
and recent genetic studies have led to a reclassification of these
as separate species, the forest population now being called Loxodonta
cyclotis, and the Savannah (or Bush) population termed Loxodonta
africana. This reclassification has important implications for conservation,
because it means where there were thought to be two small populations
of a single endangered species, there may in fact be two separate
species, each of which is even more severely endangered. There's
also a potential danger in that if the forest elephant isn't explicitly
listed as an endangered species, poachers and smugglers might thus
be able to evade the law forbidding trade in endangered animals
and their body parts.
The Forest elephant and the Savannah elephant can hybridise successfully,
though their preference for different terrains reduces the opportunities
to hybridise. Many captive African elephants are probably generic
African elephants as the recognition of separate species has occurred
relatively recently.
Although hybrids between different animal genera are usually impossible,
in 1978 at Chester Zoo, an Asian elephant cow gave birth to a hybrid
calf sired by an African elephant bull (the old terms are used here
as this pre-dates current classifications). The pair had mated several
times, but pregnancy was believed to be impossible. "Motty",
the resulting hybrid male calf, had an African elephant's cheek,
ears (large with pointed lobes) and legs (longer and slimmer), but
the toenail numbers, (5 front, 4 hind) and the single trunk finger
of an Asian elephant. The wrinkled trunk was like an African elephant.
The forehead was sloping with one dome and two smaller domes behind
it. The body was African in type, but had an Asian-type centre hump
and an African-type rear hump. Sadly the calf died of infection
12 days later. It is preserved as a mounted specimen at the British
Natural History Museum, London. There are unconfirmed rumours of
three other hybrid elephants born in zoos or circuses, all are said
to have been deformed and did not survive.
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