Panthera tigris (Tiger)

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Tiger
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Felidae
Genus: Panthera
Species: P. tigris
Binomial name
Panthera tigris
(Linnaeus, 1758)
Synonyms
Felis tigris Linnaeus, 1758

Tigris striatus Severtzov, 1858

Tigris regalis Gray, 1867

Tigers are the largest and most powerful of all the big cats. Humans are the tiger's only serious predator, who often kill tigers illegally for their fur. Also, their bones and nearly all body parts are used in traditional Chinese medicine for a range of purported uses including pain killers and aphrodisiacs. Poaching for fur and destruction of habitat have greatly reduced tiger populations in the wild. A century ago, there were approximately over 100,000 tigers in the world; now numbers are down to below 2,500 mature breeding individuals, with no subpopulation containing more than 250 mature breeding individuals[1]. All subspecies of tigers have been placed on the endangered species list. Most tigers live in forests or grasslands, for which their camouflage is ideally suited, and where it is easy to hunt prey that is faster or more agile. Among the big cats, only the tiger and jaguar are strong swimmers; tigers are often found bathing in ponds, lakes, and rivers. Tigers hunt alone and eat primarily medium to large sized herbivores such as deer, wild pigs, gaur and water buffalo. However, they also take smaller prey on occasion.

The Royal Bengal Tiger is the most common subspecies of tiger, constituting approximately 80% of the entire tiger population, and is found in the Indian subcontinent. The tiger's beautiful blend of grace and ferocity led author and conservationist Jim Corbett to remark - "The Tiger is a large hearted gentleman with boundless courage".

Panthera tigris
Singapore Zoo tigers.

Physical traits

Tigers are the largest and heaviest cats in the world[2]. Although different subspecies of tiger have different characteristics, in general male tigers weigh between 200 and 320 kg (440 lb and 700 lb) and females between 120 and 181 kg (265 lb and 400 lb). At an average, males are between 2.6 and 3.3 metres (8 feet 6 inches to 10 feet 8 inch) in length, and females are between 2.3 and 2.75 metres (7 ft 6 in and 9 ft) in length. Of the living subspecies, Sumatran tigers are the smallest, and Amur or Siberian Tigers are the largest.

The stripes of most tigers vary from brown or hay to pure black, although white tigers have far fewer apparent stripes. White tigers are not a separate sub-species; They are leucistic Indian tigers. The form and density of stripes differs between subspecies, but most tigers have in excess of 100 stripes. The now extinct Javan tiger may have had far more than this. The pattern of stripes is unique to each animal, and thus could potentially be used to identify individuals, much in the same way as fingerprints are used to identify people. This is not, however, a preferred method of identification, due to the difficulty of recording the stripe pattern of a wild tiger. It seems likely that the function of stripes is camouflage, serving to hide these animals from their prey. Few large animals have colour vision as capable as that of humans, so the colour is not as great of a problem as one is believed that they are used more to enhance daytime vision than for colour vision. [3] The stripe pattern is found on a tiger's skin and if you shaved one, you would find that its distinctive camouflage pattern would be preserved.

Hunting methods

Tigers, like other cats, are fond of the ambush. Generally, they can overpower their prey from any angle, using their massive body size and strength to knock even a large prey animal off balance. Once prone, the tiger bites the back of the prey's neck, often breaking the spinal cord, and piercing the windpipe along with the jugular vein or carotid artery. For the largest prey, a bite to the throat is preferred. After biting, the tiger then uses its muscled forelimbs to hold onto the prey, bringing it to the ground and keeping it there. The tiger remains latched onto the neck until its prey dies, usually quite rapidly after the attack.

Powerful swimmers, tigers are known to kill prey in the water as well as on land. Some tigers have even ambushed boats for their catches of fish.

Tigers never hunt humans except when deprived of their normal prey. Probably only 3 or 4 tigers out of every 1000 tigers kill a person as prey in their lifetimes, and are called "man-eaters". The usual man-eater is an injured or ill tiger which can no longer catch its preferred prey and must resort to a smaller, slower target. Sometimes a mother tiger, who is dull of tooth and arthritic of joint, will teach her cubs to hunt humans after she learned to do so to keep from starving when she could no longer capture antelope and deer. This is the likely source of young, healthy tigers who are man-eaters. Even though it is only the rare toger that hunts humans, since tigers bring down a kill every week or two, if able, some of the man-eaters of the past have each individually accounted for hundreds of death. The Sundarbans mangrove swamps of Bengal have had a higher incidence of man-eaters, and it is there that some healthy tigers have been known to hunt humans as prey.

In the wild, tigers can leap as high as 5 m and as far as 9-10 m, making them one of the highest-jumping mammals (just slightly behind cougars in jumping ability).

They have been reported to carry domestic livestock weighing 50 kg while easily jumping over fences 2 m high. Their forelimbs, massive and heavily muscled, are used to hold tightly onto the prey and to avoid being dislodged, especially by large prey such as gaurs. Gaurs and Water Buffalo weighing over a ton have been killed by tigers weighing about a sixth as much. A single tremendous blow of the paw can kill a full-grown wolf or human, or can heavily injure a 150 kg Sambar deer.

Biology and ecology

Adult tigers are solitary and fiercely territorial. A tigress may have a territory of 20 km² while the territories of males are much larger, covering 60-100 km². Male territories may overlap those of many females, but males are intolerant of other males within their territory. Because of their aggressive nature, territorial disputes are violent and often end in the death of one of the males. To identify his territory the male marks trees by spraying urine and anal gland secretions on trees as well as by marking trails with scat. Males show a behavior called flehmen, a grimacing face, when identifying the condition of a female's reproductive condition by sniffing their urine markings.

A female is only receptive for a few days and mating is frequent during that time period. A pair will copulate frequently and noisily, like other cats. The gestation period is 103 days and 3–4 cubs of about 1 kg each are born. The females rear them alone. Wandering male tigers may kill cubs to make the female receptive. At 8 weeks, the cubs are ready to follow their mother out of the den. The cubs become independent around 18 months of age, but it is not until they are around 2–2½ years old that they leave their mother. The cubs reach sexual maturity by 3–4 years of age. The female tigers generally own territory near their mother, while males tend to wander in search of territory, which they acquire by fighting and eliminating a territorial male. Over the course of her life, a female tiger will give birth to an approximately equal number of male and female cubs. Tigers breed well in captivity, and the captive population in the United States may rival the wild population of the world.

In the wild, tigers mostly feed on deer, wild boar, and wild cattle, including gaur and water buffaloes, young rhinos and young elephants, and sometimes, leopards and bears. Tigers also have been known to kill crocodiles on occasion [1], although predation is rare and the predators typically avoid one another.Siberian tigers and brown bears are a serious threat to each other and both tend to avoid each other. Statistically though, the Siberian tiger has been the more successful in battles between the two animals because bears taken by tigers are often smaller sized bears, however tigers can and do kill larger brown bears.[4] Even female tigers, which are considerably smaller than male tigers, are capable of taking down and killing adult gaurs by themselves. Sambar, wild boar and gaur are the tiger's favoured prey in India. Young elephant and rhino calves are occasionally taken when they are left unprotected by their herds. A case where a tiger killed an adult female Indian rhino has been observed [2]. Moreover,

Tigers prefer large prey such as sambar, gaur and wild water buffalo because they provide more meat and last for many days, avoiding the need for another hunt. In all of their range, tigers are the top predators and do not compete with other carnivores other than the dhole or Indian wild dog, which makes up for its relative lack of strength by numbers. They do not prey on large animals such as adult elephants and rhinos, although they will prey on their young whenever they have an opportunity. However, a hungry tiger will attack anything it regards as potential food, including humans.

Tigers have been studied in the wild using a variety of techniques. The populations of tigers were estimated in the past using plaster casts of their pugmarks. In recent times, camera trapping has been used instead. Newer techniques based on DNA from their scat are also being evaluated. Radio collaring has also been a popular approach to tracking them for study in the wild.

Subspecies

There are eight subspecies of tiger, three of which are extinct and one of which is almost certain to become so in the near future. Their historical range (severely diminished today) ran through Russia, Siberia, Iran, Afghanistan, India, China and Southeast Asia, including the Indonesian islands. The South China Tiger is believed to be the first tiger. These are the surviving subspecies, in descending order of wild population:

Bengal tiger
  • The Bengal tiger or the Royal Bengal tiger (Panthera tigris tigris) is found in parts of India, Bangladesh, Nepal, Bhutan, and Myanmar. It lives in varied habitats - grasslands, subtropical and tropical rainforests, scrub forests, wet and dry deciduous forests and mangroves. The Indian government's estimated population figure for these tigers is between 3,100 and 4,500, 3,000 of which are found in India alone. However, many Indian tiger conservationists doubt this number, seeing it as overly optimistic. The number of Bengal tigers in India may be lower than 2000 [5], as most of the collected statistics are based on pugmark identification, which often gives a biased result. Even though this is the most 'common' tiger, these tigers are under severe pressure from both habitat destruction and poaching. In 1972, India launched a massive wildlife conservation project, known as Project Tiger, to protect the depleting numbers of tigers in India. The project helped increase the population of these tigers from 1,200 in the 1970s to 3,000 in the 1990s and is considered as one of the most successful wildlife conservation programs. Recently these numbers have been found to be cooked up; At least one Tiger Reserve (Sariska) has lost its entire tiger population to poaching [3]. Male Bengal tigers can range anywhere from 200 to 295 kg (440-650 lb) and females range between 120-180 kg (264-400 lb). Most males in the wild usually weigh 205 to 227 kg (450-500 lb), while the average female will weigh about 140 kg (310 lb). However, there are recorded instances of shot males that weighed more than 300 kg. One large male killed in Nepal in 1942 weighed 318 kg (700 lbs), while another, killed in 1910 in India, weighed 317 kg (700 lbs). The largest Bengal tiger ever shot was a male 3.3 m in total length and weighed close to 390 kg (858 lb.); this feline giant was killed in 1967.
  • Indochinese tiger (Panthera tigris corbetti), also called Corbett's tiger, is found in Cambodia, China, Laos, Myanmar, Thailand, and Vietnam. Estimates of its population vary between 1,200 to 1,800, but it seems likely that the number is in the lower part of the range. The largest current population is in Malaysia, where illegal poaching is strictly controlled, but all existing populations are at extreme risk from habitat fragmentation and inbreeding. In Vietnam, almost three-quarters of the tigers killed provide stock for Chinese pharmacies. Also, the tigers are seen by poor natives as a resource through which they can ease poverty. Indochinese tigers are smaller and darker than Bengal tigers, and about the size of African lions. Males weigh from 150-190 kg on average while females are smaller at 110-140 kg.
  • The Malayan tiger (Panthera tigris jacksoni), exclusively found in the southern (Malaysian) part of the Malay Peninsula, was not considered a subspecies in its own right until 2004. The new classification came about after a study by Luo et al from the Laboratory of Genomic Diversity Study, part of the National Cancer Institute, US. Recent counts showed there are 600-800 tigers in the wild, making it the third largest tiger population behind the Bengal tiger and the Indochinese tiger. The Malayan tiger is a national icon in Malaysia, appearing on its coat of arms and in logos of Malaysian institutions, such as Maybank.
Sumatran Tiger
  • The Sumatran tiger (Panthera tigris sumatran) is found only on the Indonesian island of Sumatra. The wild population is estimated at between 400 and 500, seen predominantly in the island's five national parks. Recent genetic testing has revealed the presence of unique genetic markers, indicating that it may develop into a separate species, if it is not made extinct.[6] This has led to suggestions that Sumatran tigers should have greater priority for conservation than any other subspecies. Habitat destruction is the main threat to the existing tiger population (logging continues even in the supposedly protected national parks), but 66 tigers were recorded as being shot and killed between 1998 and 2000, or nearly 20% of the total population. The Sumatran tiger is the smallest of all living tiger subspecies. Adult males weigh between 100-130 kg, females 70-90 kg. Their small size is an adaptation to the thick, dense forests of the Sumatra island where they reside, as well as the smaller-sized prey.
Siberian Tiger
  • The Siberian tiger (Panthera tigris altaica), also known as the Amur, Manchurian or North China tiger, is confined almost completely to Siberia, where it is now protected. The last two censuses(1996 and 2005) found 450-500 Siberian tigers within their single and more or less continuous range making it one of the biggest undivided tiger populations in the world. Considered the largest subspecies, the largest wild Siberian tiger on record weighed 384 kg (845 lb.), while a captive one weighed 423 kg (930 lb.). Some Bengal tigers grow to the same length as Siberian tigers, but they are less stocky. Weights can vary substantially depending on whether the tiger has been fully fed or has an empty belly. The average weight of a male Siberian tiger is around 227 kg (500 lb), but they can be anywhere from 205 to 364 kg (450-800 lb). The Siberian tiger is also noted for its thick coat, distinguished by a paler golden hue and a smaller number of stripes. The Siberian tiger is the largest and heaviest of all living felines. A six-month old Siberian tiger can be as big as a fully grown panther.
Panthera tigris
  • The South China tiger (Panthera tigris amoyensis), also known as the Amoy or Xiamen tiger, is the most critically endangered subspecies of tiger and will almost certainly become extinct. It is also considered to be the first of all tiger subspecies. This subspecies is one of the smallest tiger species. The length of the South China tiger ranges from 2.2-2.6 m (87-104 inches) for both males and females. Males weigh between 127 and 177 kg (280-390 lb.) while females weigh between 100 and 118 kg (220-260 lb.). It seems likely that the last known wild South China tiger was shot and killed in 1994, and no live tigers have been seen in their natural habitat for the last 20 years. In 1977, the Chinese government passed a law banning the killing of wild tigers, but this appears to have been too late to save the subspecies. There are currently 59 known captive South China tigers, all within China, but these are known to be descended from only six animals. Thus, the genetic diversity required to maintain the subspecies no longer exists, making its eventual extinction very likely. Currently, there are breeding efforts to reintroduce these tigers by 2008.

Extinct tiger subspecies

Tigers are uncommon in the fossil record. The distinct fossils of tigers were discovered in Pleistocene deposits – mostly in Asia. Nevertheless, tiger fossils 100,000 years old have been found in Alaska. Possibly because of a land bridge between Siberia and Alaska during the ice ages, this Alaskan tiger might be a North American population of Siberian tiger. In addition, some scientists have discovered similarities between tiger bones and those of the American lion, an extinct big cat that dominated much of North America as recently as 10,000 years ago. Some have used these observations to conclude that the American lion was a New World tiger species.

Tiger fossils have also turned up in Japan. These fossils indicate that the Japanese tiger was no bigger than the island subspecies of tigers of recent ages. This may be due to the phenomenon in which body is related to environmental space, or in the case of a large predator like a tiger, availability of prey.

  • The Balinese tiger (Panthera tigris balica) has always been limited to the island of Bali. These tigers were hunted to extinction – the last Balinese tiger is thought to have been killed at Sumbar Kima, West Bali on 27 September 1937; this was an adult female. No Balinese tiger was ever held in captivity. The tiger still plays an important role in Balinese Hindu religion.
  • The Javan tiger (Panthera tigris sondaica) was limited to the Indonesian island of Java. It now seems likely that this subspecies was made extinct in the 1980s, as a result of hunting and habitat destruction, but the extinction of this subspecies was extremely probable from the 1950s onwards (when it is thought that fewer than 25 tigers remained in the wild). The last specimen was sighted in 1979.
  • The Caspian tiger or Persian Tiger (Panthera tigris virgata) appears to have become extinct in the late 1960s, with the last reliable sighting in 1968, though it is thought that such a tiger was last shot dead in the south-eastern-most part of Turkey in 1970. Historically it ranged through Afghanistan, Iran, Iraq, Pakistan, the former Soviet Union and Turkey. This tiger was said to be yellow with black stripes. The Caspian tiger was one of two subspecies of tiger (along with the Bengal) that was used by the Romans to battle Roman Gladiators and other animals, including the Barbary Lion.
  • The Trinil tiger (Panthera tigris trinilensis) is the oldest tiger fossil dating from about 1.2 million years ago. This tiger was found at the locality of Trinil, Java, Indonesia. [7]

Traditional Asian medicine

Tiger parts are used in traditional Chinese medicines. Many people in China believe that tiger parts have medicinal properties. There is no scientific corroboration to these beliefs, which include:

  • The tail of the tiger is sometimes ground and mixed with soap to create an ointment for use in treating skin cancer.
  • The bones found in the tip of the tiger's tail are said to ward off evil spirits.
  • Crushed tiger bones added to wine serves as a Taiwanese general tonic.
  • Tiger's skin is said to cure a fever caused by ghosts. In order to use it effectively, the user must sit on the tiger's skin, but beware. If too much time is spent on the tiger's skin, legend says the user will become a tiger.
  • Adding honey to the gallstones and applying the combination to the hands and feet is said to effectively treat abscesses.
  • Burnt tiger hair can allegedly drive away centipedes.
  • Mixing the brain of a tiger with oil and rubbing the mixture on your body is an alleged cure for both laziness and acne.
  • Rolling the eyeballs into pills is an alleged remedy for convulsions.
  • If whiskers are kept as a charm, legend says one will be protected against bullets and have increased courage.
  • One will allegedly possess courage and shall be protected from sudden fright if you wear a tiger's claw as a piece of jewelry or carry one in your pocket.
  • Strength, cunning, and courage can allegedly be obtained by consuming a tiger's heart.
  • Floating ribs of a tiger are considered a good luck talisman.
  • The tiger's penis is (erroneously) said to be an aphrodisiac.
  • Small bones in a tiger's feet tied to a child's wrists are said to be a sure cure for convulsions. [4]

Tigers in literature and popular culture

Tyger! Tyger! Burning bright
In the forests of the night,
What immortal hand or eye
Could frame thy fearful symmetry?...

William Blake, "The Tyger", Songs of Experience. The most anthologized poem in the English language.

The word "tiger" is borrowed from Greek "tigris", itself borrowed from Persian ([5]). American English "Tigress" was first recorded in 1611. Tiger's-eyes "yellowish-brown quartz" is recorded from 1891.

The tiger has certainly managed to appeal to man's imagination. Both Rudyard Kipling in The Jungle Book and William Blake in his Songs of Experience depict the tiger as a ferocious, fearful animal. In The Jungle Book, the tiger Shere Khan is the biggest and most dangerous enemy of Mowgli, the uncrowned king of the jungle. Even in the Bill Watterson comic strip, Calvin and Hobbes, Hobbes the tiger sometimes escapes his role of cuddly animal. At the other end of the scale there is Tigger, the tiger from A. A. Milne's Winnie the Pooh stories, who is always happy and never induces fear. In the award winning A Tiger for Malgudi, a Yogi befriends a tiger. Rajah, a pet of the character Jasmine of Disney's animated feature film Aladdin, is uncharacteristically dog-like in its behavior, but even more oddly Tony the Tiger is renowned for his Frosted Flakes and may be the only cat, real or fictional, who thrives on a vegetarian diet.

A stylized tiger cub was a mascot of the 1988 Summer Olympic Games of Seoul with the name "Hodori", and the tiger is one of the most chosen animals to be a mascot for sports teams, e.g. Major League Baseball team Detroit Tigers and English rugby club Leicester Tigers.

Humble Oil, a division of Standard Oil Company of New Jersey (Jersey Standard), used a stylized tiger to promote gasoline and the slogan "Put a Tiger in your Tank". Jersey Standard adopted the use of a real tiger in its advertising when it took the Exxon name company-wide in 1972, and the brand kept the tiger mascot as a part of ExxonMobil when they merged in 1999. Most recently, Yann Martel won the Man Booker Prize in 2002 with his novel Life of Pi about an Indian boy castaway on the Pacific Ocean with a Royal Bengal Tiger. In the Chinese novel Water Margin, tigers appeared numerous times as attacking travellers. In the Wu Song story he became famous when slaying with his bare hands a tiger who had been terrorizing the local towns nearly a decade. In reality, wild tigers, being dwellers of the jungle, have rarely been found in larger human cities in China, where the idea of a tiger on the street can act as a symbol of paranoia or unfounded fear, giving rise to such idioms as three men make a tiger. The Tiger is one of the 12 Chinese Zodiac animals.

In the popular children's book series Animorphs, the Siberian Tiger is the favorite and battle morph of Animorphs leader Jake.

Tiger as the national animal

The Tiger is the national animal of:

References

  1. 1.0 1.1 Database entry includes justification for why this species is endangered
  2. WWF – Tigers – Ecology.
  3. Senses part from Busch Gardens Animal Information Database - Tiger infobook.
  4. Matthiessen, Peter. Rough Beast, The New York Times, The New York Times Company, 19 March 2000. Retrieved on 23 October 2013.
  5. Task force says tigers under siege
  6. Cracraft J., Felsenstein J., Vaughn J., Helm-Bychowski K. (1998) Sorting out tigers (Panthera tigris) Mitochondrial sequences, nuclear inserts, systematics, and conservation genetics. Animal Conservation 1: 139–150.
  7. Van den Hoek Ostende. 1999. Javan Tiger - Ruthlessly hunted down. 300 Pearls - Museum highlights of natural diversity. Downloaded on 11 August 2006.