Asian Elephant

Asian Elephant[1]
Bong Su, a male Asian elephant in Melbourne Zoo
Conservation status

Endangered (IUCN 3.1)[2]
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Proboscidea
Family: Elephantidae
Genus: Elephas
Species: E. maximus
Binomial name
Elephas maximus
Linnaeus, 1758
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 Bangladesh, India, Sri Lanka, Indochina and parts of Nepal and Indonesia (primarily Borneo), Vietnam, Thailand, Cambodia, Laos, Burma, China, Bhutan, and Sumatra. It is considered endangered due to habitat loss and poaching,[3] with between 41,410 and 52,345 left in the wild.[2] Asian elephants are rather long-lived, with a maximum recorded life span of 86 years.

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.

Contents

Description

The Asian Elephant is slightly 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 2 to 3.6 metres (6.6 to 11.8 ft) in height and 3,000–5,000 kilograms (6,600–11,000 lb) 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.[4] 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.[4]

Asian elephants generally live in hot climates. Their skin is around 3–4 cm thick. Elephants eat up to 150–170 kg of vegetation a day. Asiatic elephant is endangered because of destruction of its living place.

Asian elephants are highly intelligent and self-aware[5], and they have a very large and highly convoluted neocortex, a trait also shared by humans, apes and certain dolphin species. Asian elephants have the greatest volume of cerebral cortex available for cognitive processing of all existing land animals. Elephants have a volume of cerebral cortex available for cognitive processing that exceeds that of any primate species, and extensive studies place elephants in the category of great apes in terms of cognitive abilities for tool use and tool making.[6]

Size

The sizes of elephants in the wild have been exaggerated in the past. However, record elephants may have measured as high as 3.7 metres (12 ft) at the shoulder. Height is often estimated using the rule of thumb of twice the forefoot circumference.[7]

Richard Lydekker documents sizes observed in the 19th century:

The height of the adult male usually does not exceed nine feet [2.7 m], and that of the female eight feet [2.4 m]; but these dimensions are occasionally considerably exceeded. George P. Sanderson measured a male standing nine feet seven inches [2.9 m] at the shoulder, and measuring twenty-six feet two and one-half inches [8 m] from the tip of the trunk to the extremity of the tail; and he records others respectively reaching nine feet eight inches [2.9 m] and nine feet ten inches [3 m] at the shoulder. An elephant shot by General Kinloch stood upward of ten feet one inch [3.1 m]; and another measured by Sanderson ten feet seven and one-half inches [3.2 m]. These dimensions are, however, exceeded by a specimen killed by the late Sir Victor Brooke, which is reported to have reached a height of eleven feet [3.4 m]: and there is a rumor of a Ceylon elephant of twelve feet [3.7 m]. That such giants may occasionally exist is indicated by a skeleton in the Museum at Calcutta, which is believed to have belonged to an individual living between 1856 and 1860 in the neighborhood of the Rajamahal hills, in Bengal. As now mounted this enormous skeleton stands eleven feet three inches [3.4 m] at the shoulders, but Mr. O. S. Fraser, in a letter to the Asian newspaper, states that it is made to stand too low, and that its true height was several inches more. If this be so, there can be no doubt that, when alive, this elephant must have stood fully twelve feet.[7]

A record tusk described by George P. Sanderson measured 5 feet (1.5 m) along the curve, with a girth of 16 inches (41 cm) at the point of emergence from the jaw, the weight being 104+1⁄2 pounds (47 kg). This was from an elephant killed by Sir V. Brooke and measured 8 feet (2.4 m) in length, and nearly 17 inches (43 cm) in circumference, and weighed 90 pounds (41 kg). The tusk's weight was, however, exceeded by the weight of a shorter tusk of about 6 feet (1.8 m) in length which weighed 100 pounds (45 kg).[7] 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 metres (11.0 ft) tall and 8.06 metres (26.4 ft) long.[8]

Behavior

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. The adult Asian Elephant has no natural predators, but young elephants may fall prey to tigers.

A herd of wild Indian elephants in the Jim Corbett National Park, India.

Elephants' life spans have been exaggerated in the past and live on average for 60 years in the wild and 80 in captivity.[9] 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. They sometimes eat their own poo if hungry.

Elephants use infrasound to communicate; this was first noted by the Indian naturalist M. Krishnan and later studied by Katherine Payne.[10]

Male behavior

Bull elephants may form small groups known as 'bachelor herds', but bulls may also roam independently at various times. Bulls will fight one another to get access to estrous females. Males reach sexual maturity around age 12-15 (younger in captivity). By their late teens or early twenties, bulls undergo an annual phenomenon known as "musth". This is a period where the testosterone level is high (up to 100 times greater than non-musth periods) and they become extremely aggressive. Secretions containing pheromones occur during this period, from the paired temporal glands located on the head between the lateral edge of the eye and the base of the ear. At the height of musth, bulls also become urine incontinent, and will discharge urine continuously. Over time, they develop a greyish/greenish tinge to their prepuce which has been termed 'green penis'.

Female behavior

An Asian elephant Kwunjai and baby Gabi, at the Jerusalem Biblical Zoo.

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. Once a female gives birth, she usually does not breed again until the first calf is weaned, resulting in a 4-5 year birth interval. 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.[11][12]

Trunk

The trunk is an amazing organ of extreme dexterity: it is the single most important feature of an elephant, and gives the Order Proboscidea its name. The trunk is very strong , which is its ideal tool for eating. It is actually a fusion between the nose and upper lip, and consists of some 100 000 muscle units, which allow the elephant to move the trunk with such a wide range of movement.

Elephants use their trunks to, among other things: breathe through, smell with, to pick up water to drink (the trunk can hold 8.5 litres), to pick leaves, fruit, etc., either off trees or off the ground, to cover themselves with mud, water or dust, and to communicate with each other, via touch, smell and the production of sound. It is also used for lifting objects and as a weapon. African elephants have two 'fingers' at the tip of the trunk, which are fleshy, mobile and very sensitive.

Danger

Mahouts washing an elephant, Thrissur, Kerala.

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;[7] xylazine is also used.

The Borneo elephant is smaller with relatively larger ears, a longer tail, and straighter tusks. It is also smaller than other subspecies of the Asian elephant.

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."[7]

Captivity

Used for tourism throughout Asia
At this elephant training camp, captive elephants are taught to handle logs.
The elephant namely Soman at the elephant training centre, Konni, Pathanamthitta

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.[13]

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.

Subspecies

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:

Elephants in Kerala are trained not to move when Valiya kol (long pole) is kept on him.
An elephant named Sri Hari during Sree Poornathrayesa temple festival, Thrippunithura.

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[14].

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. sumatranus 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.[15]

In addition, two extinct subspecies are considered by some authorities to have existed:

See also

References

  1. ↑ Shoshani, Jeheskel (16 November 2005). "Order Proboscidea (pp. 90-91)". In Wilson, Don E., and Reeder, DeeAnn M., eds. Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Baltimore: Johns Hopkins University Press, 2 vols. (2142 pp.). p. 90. ISBN 978-0-8018-8221-0. OCLC 62265494. http://www.bucknell.edu/msw3/browse.asp?id=11500004. 
  2. ↑ 2.0 2.1 Choudhury, A., Lahiri Choudhury, D.K., Desai, A., Duckworth, J.W., Easa, P.S., Johnsingh, A.J.T., Fernando, P., Hedges, S., Gunawardena, M., Kurt, F., Karanth, U., Lister, A., Menon, V., Riddle, H., Rübel, A. & Wikramanayake, E. (2008). Elephas maximus. In: IUCN 2008. IUCN Red List of Threatened Species. Downloaded on 28 October 2008.
  3. ↑ Cynthia Turnage and Mark McGinley. 2010. Asian Elephant. Encyclopedia of Earth. C. Michael Hogan, Topic editor. eds. Cutler J. Cleveland. National Council for Science and the Environment, Washington DC
  4. ↑ 4.0 4.1 Clutton-Brock, Juliet (1987). A Natural History of Domesticated Mammals. London: British Museum (Natural History). pp. 208. ISBN 0521346975. 
  5. ↑ Aldous, Peter (2006-10-30). "Elephants see themselves in the mirror". New Scientist. http://www.newscientist.com/article/dn10402-elephants-see-themselves-in-the-mirror.html. Retrieved 2010-08-29. 
  6. ↑ Hart, B.L.; L.A. Hart, M. McCoy, C.R. Sarath (November 2001). "Cognitive behaviour in Asian elephants: use and modification of branches for fly switching". Animal Behaviour (Academic Press) 62 (5): 839–847. doi:10.1006/anbe.2001.1815. http://www.ingentaconnect.com/content/ap/ar/2001/00000062/00000005/art01815. Retrieved 2007-10-30. 
  7. ↑ 7.0 7.1 7.2 7.3 7.4 Lydekker, R. (1894). The Royal Natural History. Volume 2. 
  8. ↑ Wood, The Guinness Book of Animal Facts and Feats. Sterling Pub Co Inc (1983), ISBN 978-0-85112-235-9
  9. ↑ Shoshani, Jeheskel; John F. Eisenberg (1982). "Elephas maximus". Mammalian Species 182: 1–8. doi:10.2307/3504045. http://jstor.org/stable/3504045. 
  10. ↑ Payne, Katherine (1998). Silent Thunder. Simon & Schuster. ISBN 0-684-80108-6. 
  11. ↑ 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.
  12. ↑ Rasmussen, L. E. L., Lee, T. D., Roelofs, W. L., Zhang, A. J. & Daves, G. D. (1996). Insect pheromone in elephants. Nature, 379, 684.
  13. ↑ Rangarajan, M. (2001) India's Wildlife History, pp 6.
  14. ↑ Elefantasia 2008, Assist Us, 1 January 2008
  15. ↑ 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 Full text

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