African elephants are the species of
elephantElephants are large land mammals in two genera of the family Elephantidae: Elephas and Loxodonta. Three species of elephant are living today: the African Bush Elephant, the African Forest Elephant and the Asian Elephant...
s in the
genusIn biology, a genus is a taxonomic unit used in the classification of living and fossil organisms. The term comes from Latin genus "descent, family, type, gender" , cognate with – genos, "race, stock, kin" ..In addition, genus is a taxonomic rank in the hierarchy In biology, a genus (plural:...
Loxodonta, one of the two existing genera in
ElephantidaeElephantidae is a taxonomic family, collectively elephants and mammoths. These are terrestrial large mammals with a trunk and tusks. Most genera and species in the family are extinct...
. Although it is commonly believed that the genus was named by
Georges CuvierGeorges Léopold Chrétien Frédéric Dagobert Cuvier was a French naturalist and zoologist. Of humble working class origins, he belonged to a new class of self-made scholars who worked their way to the top of academe...
in 1825, Cuvier spelled it
Loxodonte. An anonymous author romanized the spelling to
Loxodonta and the
ICZNThe International Code of Zoological Nomenclature is both a book containing a set of rules and recommendations on the formal naming of animals, and that set itself. Among zoologists it is often referred to simply as "the Code"...
recognizes this as the proper authority.
FossilFossils are the preserved remains or traces of animals, plants, and other organisms from the remote past. The totality of fossils, both discovered and undiscovered, and their placement in fossiliferous rock formations and sedimentary layers is known as the fossil record...
Loxodonta have only been found in
AfricaAfrica is the world's second-largest and second most-populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area. With a billion people in 61 territories, it accounts for about 14.8% of the...
, where they developed in the middle
PlioceneThe Pliocene epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present....
.
African elephants are bigger than
Asian ElephantThe Asian or Asiantic Elephant , sometimes known by the name of one of its subspecies – the Indian Elephant, is one of the three living species of elephant, and the only living species of the genus Elephas. It is the largest living land animal in Asia...
s.
African elephants are the species of
elephantElephants are large land mammals in two genera of the family Elephantidae: Elephas and Loxodonta. Three species of elephant are living today: the African Bush Elephant, the African Forest Elephant and the Asian Elephant...
s in the
genusIn biology, a genus is a taxonomic unit used in the classification of living and fossil organisms. The term comes from Latin genus "descent, family, type, gender" , cognate with – genos, "race, stock, kin" ..In addition, genus is a taxonomic rank in the hierarchy In biology, a genus (plural:...
Loxodonta, one of the two existing genera in
ElephantidaeElephantidae is a taxonomic family, collectively elephants and mammoths. These are terrestrial large mammals with a trunk and tusks. Most genera and species in the family are extinct...
. Although it is commonly believed that the genus was named by
Georges CuvierGeorges Léopold Chrétien Frédéric Dagobert Cuvier was a French naturalist and zoologist. Of humble working class origins, he belonged to a new class of self-made scholars who worked their way to the top of academe...
in 1825, Cuvier spelled it
Loxodonte. An anonymous author romanized the spelling to
Loxodonta and the
ICZNThe International Code of Zoological Nomenclature is both a book containing a set of rules and recommendations on the formal naming of animals, and that set itself. Among zoologists it is often referred to simply as "the Code"...
recognizes this as the proper authority.
FossilFossils are the preserved remains or traces of animals, plants, and other organisms from the remote past. The totality of fossils, both discovered and undiscovered, and their placement in fossiliferous rock formations and sedimentary layers is known as the fossil record...
Loxodonta have only been found in
AfricaAfrica is the world's second-largest and second most-populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area. With a billion people in 61 territories, it accounts for about 14.8% of the...
, where they developed in the middle
PlioceneThe Pliocene epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present....
.
Size
African elephants are bigger than
Asian ElephantThe Asian or Asiantic Elephant , sometimes known by the name of one of its subspecies – the Indian Elephant, is one of the three living species of elephant, and the only living species of the genus Elephas. It is the largest living land animal in Asia...
s. Males stand 3.64 meters (12 ft) tall at the shoulder and weigh 5,455 kg (12,000 lbs), while females stand 3 meters (10 ft) and weigh 3,636 kg to 4,545 kg (8,000 to 11,000 lbs). However, males can get as big as 15,000 lbs (6,800 kg).
Teeth
Elephants have four molars; each weighs about and measures about 12 inches long. As the front pair wear down and drop out in pieces, the back pair shift forward and two new molars emerge in the back of the mouth. Elephants replace their teeth six times. At about 40 to 60 years of age the elephant no longer has teeth and will likely die of starvation, a common cause of death.
Their tusks are teeth; the second set of incisors become the tusks. They are used for digging for roots and stripping the bark off trees for food, for fighting each other during mating season, and for defending themselves against predators. The tusks weigh from 50-100 pounds and can be from 5 to long. Unlike Asian elephants, both male and female African elephants have tusks.
. The
enamel platesTooth enamel is the hardest and most highly mineralized substance of the body, and with dentin, cementum, and dental pulp is one of the four major tissues which make up the tooth in vertebrates. Tooth enamel is also found in the dermal denticles of sharks. It is the normally visible dental tissue...
of the molars are lesser in number than in Asian elephants.
Species
- Loxodonta adaurora, extinct, presumed antecedent of the modern African elephants.
- African Bush Elephant
The African Bush Elephant is the larger of the two species of African elephant. Both it and the African Forest Elephant have usually been classified as a single species, known simply as the African Elephant. Some authorities still consider the currently available evidence insufficient for...
(Loxodonta africana).
- African Forest Elephant
The African Forest Elephant was until recently considered a subspecies of the African Bush Elephant ; however, DNA testing has now shown that there are three extant elephant species: the two African types, formerly considered to be different populations of a single species; and the South Asian...
(Loxodonta cyclotis).
Bush and Forest Elephants were formerly considered
subspeciesSubspecies in biological classification, is 1) a taxonomic rank subordinate to species, or 2) a taxonomic unit, a taxon in that rank...
of the same species
Loxodonta africana. However, they are nowadays generally considered to be two distinct species . The African Forest Elephant has a longer and narrower mandible, rounder ears, a different number of toenails, straighter and downward tusks, and considerably smaller size. With regard to the number of toenails: the African Bush Elephant normally has 4 toenails on the front foot and 3 on the hind feet, the African Forest Elephant normally has 5 toenails on the front foot and 4 on the hind foot (like the Asian elephant), but hybrids between the two species commonly occur.
Conservation
Poaching significantly reduced the population of
Loxodonta in certain regions during the 20th century. An example of this poaching pressure is in the eastern region of Chad—elephant herds there were substantial as recently as 1970, with an estimated population of 400,000; however, by 2006 the number had dwindled to about 10,000. The African elephant nominally has governmental protection, but
poachingPoaching is the illegal hunting, fishing, trapping, or eating of wild plants or animals contrary to local and international conservation and wildlife management laws...
is still a serious issue.
Human encroachment into or adjacent to natural areas where bush elephants occur has led to recent research into methods of safely driving groups of elephants away from humans, including the discovery that playback of the recorded sounds of angry honey bees are remarkably effective at prompting elephants to flee an area. Some elephant communities have grown so large, in Africa, that some communities have resorted to culling large amounts to help sustain the ecosystem.
http://news.bbc.co.uk/1/hi/world/africa/4392800.stm
External links