White tiger

White tigers have pink noses and white to cream colored fur with black, grey or chocolate-colored stripes; their eyes are usually blue, but may be green or amber. There are around 600 white tigers in the world. Because this coloration is so striking, white tigers have become popular attractions in zoos and entertainment that showcases exotic animals; the magicians Siegfried and Roy are famous for using several trained white tigers in their shows. Contrary to popular belief, white tigers are not an endangered species in their own right, but are a selectively bred mutant form of normal orange tigers.

Related Topics:
Zoo - Magician - Siegfried and Roy

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The color is caused by a recessive gene. The gene for white coloration is usually associated with Bengal tigers, although the vast majority of Bengal tigers have normal, orange-and-black coloration. White tigers have occurred in the Amur subspecies. Two registered pure-bred Amur (Siberian) brothers bred at Como Zoo, Minnesota carried the white gene. Their wild-caught parents were pure Amur tigers. These white Amur tigers have been interbred with white Bengal tigers as well as leaving pure-bred Amur offspring. As well as white generic tigers and white Bengal tigers, there are purebred white Amur tigers in existence. Most white tigers bred in captivity are generic tigers i.e. hybrids of two subspecies - most commonly, half Bengal and half Siberian.

Related Topics:
Recessive - Gene - Bengal tigers - Hybrid - Subspecies - Siberian

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Contrary to popular belief, white tigers are not albino; true albino tigers would have no stripes. Since "white tigers" are not actually pure white, they are sometimes called chinchilla tigers in order to avoid confusion. Other names are ice tigers referring to their frosty appearance and not to their habitat. There is no evidence of true albinism in modern tigers; to date, all so-called "albino tigers" have so far been chinchilla tigers with unusually pale stripes. Part of the confusion is due to the mis-identification of the chinchilla gene as an allele of the albino series (publications prior to the 1980s refer to it as an albino gene).

Related Topics:
Albino - Allele

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The only case of true albino tigers was recorded in 1922 at Mica Camp, Tisri in the Indian state of Cooch Behar when two pink-eyed albino young tigers were shot along with their mother. Lydekker (1907) doubted the existence of albino tigers, but old records of Cooch Behar describe a tawny tigress who was shot along with 2 coloured and 2 sickly-looking white cubs (young adult tigers) that had extended necks and pink eyes. In "Animal kingdom", the 18th century French naturalist Baron Georges Cuvier described a white tigress whose stripes were visible only at certain angles of reflection.

Related Topics:
Lydekker - Cuvier

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A pure white tiger was described in the 1800s and showing ghost stripes: "A wholly white tiger, with the stripe-pattern visible only under reflected light, like the pattern of a white tabby cat, was exhibited in the Exeter Change Menagerie in 1820 and described by Hamilton Smith".

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All white tigers currently in captivity can trace ancestry to a single individual - a male named Mohan, captured in India in 1951. Although Mohan was not the first white tiger in captivity, he was the first to successfully breed in captivity. Because the gene pool is so small, many white tigers suffer from health problems due to inbreeding. For this reason, responsible zoos refuse to breed two white tigers together. However, two white parents are the only way to ensure white cubs; if a white tiger mates with a partner that is heterozygous for the gene, only one in four of the offspring will be white. Thus, due to the high demand for white tigers, unscrupulous breeders sometimes still breed white tigers together. Some animal rights activists have called for a halt to the breeding of white tigers altogether.

Related Topics:
Inbreeding - Heterozygous - Animal rights

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White tigers have always been extremely rare in the wild. Since Mohan's capture, there have been no further confirmed sightings, although zoologists believe that the gene may still be found in certain wild Bengal tiger populations.

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White tigers tend to be larger than their orange (normal) relatives. This has led to suggestions that the gene promotes larger size and that the disadvantageous white colour in homozygoutes is a side effect. The Zoo Outreach Organization in Tamil Nadu, India maintains a white tiger studbook compiled by AK Roychoudhury of the Bose Institute in Calcutta.

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