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African Elephant

The African savanna elephant (Loxodonta africana) is the best-known and largest of the two African elephants. Both it and the forest elephant were previously classified as a single species, which was known simply as the African elephant. It is also known as the bush elephant or African bush elephant.

The savanna elephant is a large animal that normally reaches 6 to 7.3 m (20 to 24 ft) in length and 3 to 3.5 meters in height, although a 4-meter elephant, whose body is dissected in the Museum of Natural History in Washington, D.C., was discovered in Angola in 1955. Weighing between 7,000 and 10,000 kg (22,000 lb), it is the largest land animal in the world. It can move at a rate of 6 km/h, but it can reach a top speed of 40 km/h when scared or upset.

The animal is characterized by its large head; two large ears that cover its shoulders and radiate excess heat; a large and muscular trunk; two prominent "tusks" (incisors), which are well-developed in both sexes, although more commonly in males; a short, almost nonexistent neck; a large, barrel-like body; four long and heavy legs that resemble columns; and a relatively short tail.

Until recently, it was thought that the so-called Forest Elephant (Loxodonta cyclotis) was simply a subspecies of the African Savannah Elephant (Loxodonta africana). DNA testing has now shown that there are in fact three extant elephant species: the two African types (formerly considered to be separate populations of a single species, the African Elephant) and the South Asian species, known as the Indian or Asian Elephant. The North African elephant of Hannibal fame was a now-extinct fourth species or a subspecies of the Forest Elephant (Loxodonta (africana) pharaoensis); it disappeared around the 1st or 2nd century CE. The disputed dwarf elephants of the Congo basin, often assumed to be a separate species (Loxodonta pumilio), are probably Forest Elephants whose diminutive size and/or early maturity is due to environmental conditions.

Differences include the Forest Elephant's long, narrow mandible (the Savannah Elephant's is short and wide), its rounded ears (a Savannah Elephant's ears are more pointed), a different number of toenails, different tusks, and considerably smaller size. Male Forest Elephants rarely exceed 2.5 meters (8 feet) in height, while Savannah Elephants are usually over 3 meters (just under 10 feet) and sometimes almost 4 meters (13 feet) tall.

African Elephants are herbivorous. The diet of a savanna elephant varies according to its habitat; elephants living in forests, partial deserts, and grasslands all eat different proportions of herbs and tree or shrubbery leaves. In order to break down the plants they consume, savanna elephants have four large molars, two in each mandible of the jaw. Over time, these molars are worn away and new ones are grown to replace them as the elephant ages. Around the age of 15 their milk teeth are replaced by new ones that last until the age of 30, and then by another ones which wore off past the age of 40, being replaced by the last teeth that last approximately until the age of 65, 70 at longest. Not much later, the animal dies of starvation not being able to feed correctly. There are known cases of over 80 year old specimens in captivity.

These animals are considered quite 'wasteful', as it's normal that they ingest an average of 225 kg of vegetal matter that is defecated without being totally digested. That, combined with the long distanced that they can cover daily in search of more food, contributes notably to the dispersion of many plant seeds that germinate in the middle of a nutrient-filled feces mound. In their feeding-oriented whereabouts, elephants rip apart all kind of plants, and


knock down trees with the tusks if they are not able to reach the tree leaves. It can be said that they carry devastation with them. That causes deep trouble for other species and to the elephants themselves in national parks where there is overpopulation, so that managers of overpopulated parks often contact other parks with fewer specimens to transfer excess individuals.

Packs are made up of related females and their younglings of assorted ages, directed by the eldest female, called the matriarch. In occasions an adult male goes with them, but those usually leave the pack when reaching adolescence to form packs with other elephants of the same age. Later, they spread out, carrying out a lonely life, approaching the female packs only during the mating season. Nevertheless, elephants don't get too far from their families and recognize them when re-encountered. Sometimes, several female packs can blend for a period of time, reaching even hundreds of individuals.

The adult savanna elephant lacks predators thanks to its great size, but the calves (especially the newborn) are vulnerable to lions', leopards' or crocodiles' and more rarely hyenas' attacks. This predation and the lack of water in drought seasons cause a considerable infant mortality in this species, in spite of the efforts made by all the females of the group, who usually attack any dangerous animal who dares to approach them. Amongst all the species, savanna elephants show special aversion towards rhinoceros, even to the point that they will attack them on sight. The behavior can be observed mostly on males, especially the younger ones.

Lastly, man should be mentioned, who has given chase to the African elephant since the olden days, for its meat as well as its valuable tusks. The elephant hunting really increased in the 19th and 20th centuries, when the sport hunting (which is more and more demanded by european and american elites every year) added to the scenery and many savanna extensions were turned into plantations. In 1989 hunting of the african elephant and ivory trading were forbidden, after the elephant population passed from several millions at the beginning of the 20th century to less than 700,000 at the end of it. The 80s were especially bloody, as the population was halved during these years. Scientists then estimated that, if no measure was taken, the wild elephant would be extinct by 1995. Luckily, the protection that the elephant receives nowadays has been successful and that prediction has been avoided, but despite the increasingly harder penalties imposed by the african governments against illegal hunting, this still happens every day. CITES still considers this species as threatened with extinction.



This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "African Elephant ".