Asian Elephant

Asian Elephant

Taxobox
name = Asian ElephantMSW3 Shoshani|pages=90]
status = EN
status_system = iucn3.1
status_ref = [IUCN2006|assessors=Asian Elephant Specialist Group|year=1996|id=7140|title=Elephas maximus|downloaded=10 May 2006 Listed as Endangered (EN A1cd v2.3) ]






regnum = Animalia
phylum = Chordata
classis = Mammalia
ordo = Proboscidea
familia = Elephantidae
genus = "Elephas"
species = "E. maximus"
binomial = "Elephas maximus"
binomial_authority = Linnaeus, 1758
range_

range_map_caption = Asian Elephant range
The Asian or Asiatic Elephant ("Elephas maximus"), 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. The species is found primarily in large parts of Bangladesh, India, Sri Lanka, Indochina and parts of Indonesia. It is considered endangered, with between 25,600 and 32,750 left in the wild. [ [http://assets.panda.org/downloads/asian_elephant_factsheet2006.pdf World Wildlife Fund factsheet] ]

This animal is widely domesticated, and has been used in forestry in South and Southeast Asia for centuries and also in ceremonial purposes. Historical sources indicate that they were sometimes used during the harvest season primarily for milling. Wild elephants attract tourist money to the areas where they can most readily be seen, but damage crops, and may enter villages to raid gardens.

Description

The Asian elephant is smaller than its African relatives; the easiest way to distinguish the two is that the Asian elephant has smaller ears. The Asian Elephant tends to grow to around two to four meters (7–12 feet) in height and 3,000–5,000 kilograms (6,500–11,000 pounds) in weight.

The Asian Elephant has other differences from its African relatives, including a more arched back than the African, one semi-prehensile "finger" at the tip of its trunk as opposed to two, four nails on each hind foot instead of three, and 19 pairs of ribs instead of 21. Also, unlike the African elephant, the female Asian Elephant usually lacks tusks; if tusks — in that case called "tushes" — are present, they are barely visible, and only seen when the female opens her mouth. The enamel plates of the molars are greater in number and closer together in Asian elephants. cite book | author = Clutton-Brock, Juliet| title = A Natural History of Domesticated Mammals | year = 1987 | pages = pp.208 | id = ISBN 0521346975] Some males may also lack tusks; these individuals are called "makhnas", and are especially common among the Sri Lankan elephant population. Furthermore, the forehead has two hemispherical bulges, unlike the flat front of the African elephant. Unlike African elephants which rarely use their forefeet for anything other than digging or scraping soil, Asian elephants are more agile at using their feet in conjunction with the trunk for manipulating objects.

ize

The sizes of elephants in the wild have been exaggerated in the past. However, record elephants may have measured as high as convert|12|ft|m at the shoulder. Height is often estimated using the rule of thumb of twice the forefoot circumference.cite book | author = Lydekker, R. | year = 1894 | title = The Royal Natural History. Volume 2]

A record tusk described by George P. Sanderson measured five feet along the curve, with a girth of sixteen inches (406 mm) at the point of emergence from the jaw, the weight being one hundred and four and one-half pounds. This was from an elephant killed by Sir V. Brooke and measured eight feet in length, and nearly seventeen inches in circumference, and weighed ninety pounds. This tusk's weight is, however, exceeded by [the weight of] a shorter tusk of about six feet in length which weighed one hundred pounds. The heaviest wild male recorded was shot by the Maharajah of Susang in the Garo Hills of Assam, India in 1924, and was 8 tonnes (8.8 short tons), 3.35 m (11.1 ft) tall and 8.06 m (26.6 ft) long. [Wood, The Guinness Book of Animal Facts and Feats. Sterling Pub Co Inc (1983), ISBN 978-0851122359]

Behaviour

In the wild, elephant herds follow well-defined seasonal migration routes. These are made around the monsoon seasons, often between the wet and dry zones, and it is the task of the eldest elephant to remember and follow the traditional migration routes. When human farms are founded along these old routes there is often considerable damage done to crops, and it is common for elephants to be killed in the ensuing conflicts.Elephants life spans have been exaggerated in the past and live on average for 60 years in the wild and 80 in captivity. [cite journal|title=Elephas maximus|first=Jeheskel|last=Shoshani|coauthors=John F. Eisenberg|journal=Mammalian Species|volume=182|year=1982|pages=1–8|doi=10.2307/3504045] They eat 10% of their body weight each day, which for adults is between 170-200 kilograms of food per day. They need 80–200 litres of water a day, and use more for bathing. They sometimes scrape the soil for minerals.

Elephants use infrasound to communicate; this was first noted by the Indian naturalist M. Krishnan and later studied by Katherine Payne. [cite book | last = Payne | first = Katherine | year = 1998 | title = Silent Thunder | publisher = Simon & Schuster | id = ISBN 0-684-80108-6]

Male behavior

Bull elephants are usually solitary, and fight over females during the breeding season. Younger bulls may form small groups. Males reach sexual maturity during their 15th year, after which they annually enter "musth". This is a period where the testosterone level is high (up to 60 times greater) and they become extremely aggressive. Secretions containing pheromones occur during this period, from the temporal glands on the forehead.

Female behavior

Female elephants live in small groups. They have a matriarchal society, and the group is led by the oldest female. The herd consists of relatives. An individual reaches sexual maturity at 9-15 years of age. The gestation period is 18–22 months, and the female gives birth to one calf, or occasionally twins. The calf is fully developed by the 19th month but stays in the womb to grow so that it can reach its mother to feed. At birth, the calf weighs about 100 kg (220 lb), and is suckled for up to 2–3 years. Females stay on with the herd, but mature males are chased away.

Females produce sex pheromones; a principal component thereof, (Z)-7-dodecen-1-yl acetate, has also been found to be a sex pheromone in numerous species of insects. [Rasmussen, L. E. L., Lee, T. D., Zhang, A. J., Roelofs, W. L. & Daves, G. D. (1997). Purification, identification, concentration and bioactivity of (Z)-7-dodecen-1-yl acetate: sex pheromone of the female Asian elephant, "Elephas maximus". Chemical Senses, 22, 417–437.] [Rasmussen, L. E. L., Lee, T. D., Roelofs, W. L., Zhang, A. J. & Daves, G. D. (1996). Insect pheromone in elephants. Nature, 379, 684.]

Danger

At most seasons of the year the Indian elephant is a timid animal, much more ready to flee from a foe than to make an attack. Solitary "rogues" are, however, frequently an exception to this rule, and sometimes make unprovoked attacks on passers-by. Rogue elephant sometimes take up a position near a road, and make it impassable to travellers. Females with calves are at all times dangerous to approach. Contrary to what is stated to be the case with the African species, when an Indian elephant makes a charge, it does so with its trunk tightly curled up, and it makes its attack by trampling its victim with its feet or knees, or, if a male, by pinning it to the ground with its tusks. During "musth" the male elephant is highly dangerous, not only to human beings, but to its fellow animals. At the first indications of this, domestic elephants are secured tightly to prevent any mishaps; xylazine is also used.While elephant charges are often displays of aggression that do not go beyond threats, some elephants, such as rogues, may actually attack.

In regard to movement on land, Mr. Sanderson says that "the only pace of the elephant is the walk, capable of being increased to a fast shuffle of about fifteen miles (24 km) an hour for very short distances. It can neither trot, canter, nor gallop. It does not move with the legs on the same side together, but nearly so. A very good runner might keep out of an elephant's way on a smooth piece of turf, but on the ground in which they are generally met with, any attempt to escape by flight, unless supplemented by concealment, would be unavailing."

When an elephant does charge, it requires all the coolness and presence of mind of the sportsman to avoid a catastrophe- "A grander animated object," writes Mr. Sanderson, "than a wild elephant in full charge can hardly be imagined. The cocked ears and broad forehead present an immense frontage; the head is held high, with the trunk curled between the tusks, to be uncoiled in the moment of attack; the massive fore-legs come down with the force and regularity of ponderous machinery; and the whole figure is rapidly foreshortened, and appears to double in size with each advancing stride. The trunk being curled and unable to emit any sound, the attack is made in silence, after the usual premonitory shriek, which adds to its impressiveness. The usual pictorial representations of the Indian elephant charging with upraised trunk are accordingly quite incorrect."

Captivity

Elephants have been captured from the wild and tamed for use by humans. Their ability to work under instruction makes them particularly useful for carrying heavy objects. They have been used particularly for timber-carrying in jungle areas. Other than their work use, they have been used in war, in ceremonies, and for carriage. They have been used for their ability to travel over difficult terrain by hunters, for whom they served as mobile hunting platforms. The same purpose is met in safaris in modern times.

The first historical record of domestication of Asian elephants was in Harappan times. Ultimately the elephant went on to become a siege engine, a mount in war, a status symbol, a work animal, and an elevated platform for hunting during historical times in South Asia.Rangarajan, M. (2001) India's Wildlife History, pp 6.]

The elephant plays an important part in the culture of the subcontinent and beyond, featuring prominently in Jataka tales and the Panchatantra. It plays a major role in Hinduism: the god Ganesha's head is that of an elephant, and the "blessings" of a temple elephant are highly valued. Elephants have been used in processions in Kerala where the animals are adorned with festive outfits. They were also used by almost all armies in India as war elephants, terrifying opponents unused to the massive beast.

ubspecies

"Elephas maximus" is the only surviving species in the "Elephas" genus, although several extinct fossil species of "Elephas" are known.

There are four living subspecies of the Asian elephant:

* Indian Elephant ("E. m. indicus")
* Sri Lankan Elephant ("E. m. maximus")
* Sumatran Elephant ("E. m. sumatrensis")
* Borneo Elephant ("E. m. borneensis")The population in Vietnam and Laos is undergoing tests to determine if it is a fifth subspecies. This research is considered vital as there are less than 1300 wild Asian elephants remaining in Laos [Elefantasia 2008, "Assist Us", 1 January 2008, [http://www.elefantasia.org/spip.php?rubrique3&lang=en] ] .

"E. m. indicus" survives in separate ranges in southern India, the Himalayan foothills, and northwest India; it is also found in southern China, Burma, Thailand, Cambodia and the Malaysian peninsula. Most males of this subspecies have tusks.
"E. m. maximus" is only found in Sri Lanka. It has a larger skull relative to body size, and commonly has a decolourised area of skin on the forehead and the front of the upper trunk. It is rare to find even males with tusks. Males can reach a height of 3.5 metres at the shoulder.
"E. m. sumatrensis" is only found in Sumatra, Indonesia. It is the second smallest subspecies, between 1.7 to 2.6 metres at the shoulder. It is sometimes called the pocket elephant because of its size.
"E. m. borneensis" is found in north Borneo (east Sabah and extreme north Kalimantan). It is smaller than all the other subspecies. It has larger ears, a longer tail, and straighter tusks. Genetic tests found that its ancestors separated from the mainland population about 300,000 years ago.Fernando P, Vidya TNC, Payne J, Stuewe M, Davison G, et al. (2003) DNA Analysis Indicates That Asian Elephants Are Native to Borneo and Are Therefore a High Priority for Conservation. PLoS Biol 1(1): e6 [http://biology.plosjournals.org/perlserv?request=get-document&doi=10.1371/journal.pbio.0000006 Full text] ]

In addition, two extinct subspecies are considered by some authorities to have existed:
*The Chinese population is sometimes separated as "E. m. rubridens" (pink-tusked elephant); it disappeared after the 14th century BC.
*The Syrian Elephant ("E. m. asurus"), the westernmost and the largest subspecies of the Asian Elephant, went extinct around 100 BC. This latter population, along with other Indian elephants, were considered the best war elephants in antiquity, and found superior to the smallish North African Elephant ("Loxodonta africana pharaonensis") used by the armies of Carthage.

ee also

* Batyr, an Asian Elephant who could imitate human speech
* Elephants in Kerala culture
* Elefantasia for information on Asian elephants in Laos

References

External links

* [http://www.asianelephant.net/ Asian Elephants at the Zoological Gardens of the World]
* [http://nationalzoo.si.edu/Animals/AsianElephants/ National Zoo Facts on Asian Elephant and a Webcam of the Asian Elephant exhibit]
* [http://www.chaffeezoo.org/animals/elephant.html The Chaffee Zoo Asian Elephant Fact Sheet]
* [http://ecos.fws.gov/species_profile/servlet/gov.doi.species_profile.servlets.SpeciesProfile?spcode=A059 U.S. Fish & Wildlife Species Profile]
* [http://www.elefantasia.org For information on Asian Elephants in Laos]


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