Color Variation of Tiger
The orange colored tiger with black stripes is, of course, the most prevalent. There are different shades of orange ranging from almost yellow to dark burnt orange. The stripes also vary in shade, size and abundance. Some tigers will have dark, wide stripes while some have fewer stripes that are narrower. It is interesting to note that every stripe pattern is unique. No two tigers are marked the same, much like a person's fingerprints.
Color and striping is controlled by gene groups that are inherited from the parent's genes, the same as hair color in humans. A person may have dark hair and that would be the trait they most likely would pass on to their children, especially if both parents have the same color gene. If one parent has a dark hair, and the other has blond hair, the child will usually have dark hair because the gene for dark hair is dominant. In order for the child to have blonde hair, the parent with dark hair must also have a recessive gene for blonde hair. Then the child has a 50/50 chance to have either color hair. Recessive genes are what cause different color variations - in tigers as well as people. It is what causes a white tiger to be born from two standard colored parents.
Orange Tiger
The orange colouring is the most common color of tiger. Every subspecies of tiger can be orange. Whereas some of the more exotic colours are limited to certain subspecies.
White Tiger
A white tiger is caused by the homozygous occurrence of a recessive allele in the genome. Estimations show that around one in 10,000 wild Bengal tiger births will result in a white tiger. The white tiger is not considered a tiger subspecies, but rather a mutant variant of the existing tiger subspecies.
Snow White Tiger
An additional genetic condition can remove most of the striping of a white tiger, making the animal almost pure white. One such specimen was exhibited at Exeter Change in England in 1820. The modern strain of snow white tigers came from repeated brother–sister mating of Bhim and Sumita. The gene involved may have come from a Siberian tiger; continued inbreeding appears to have caused a recessive gene for stripelessness to show up.
Golden Tabby Tiger
It is sometimes referred to as the strawberry tiger due to the strawberry blonde coloration. A golden tabby tiger is one with an extremely rare color variation caused by a recessive gene and is currently only found in captive tigers. Like the white tiger, it is a color form and not a separate species. In the case of the golden tiger, this is the wide band gene; while the white tiger is due to the color inhibitor (chinchilla) gene. There are currently believed to be fewer than 30 of these rare tigers in the world. The golden tiger's white coat and gold patches make it stand out from the norm. Their striping is much paler than usual and may fade into spots or large prominent patches. Golden tigers also tend to be larger and, due to the effect of the gene on the hair shaft, have softer fur than their orange relatives.
Maltese Tiger
The Maltese tiger, or blue tiger, is a semi-hypothetical coloration morph of a tiger, reported mostly in the Fujian Province of China. It is said to have bluish fur with dark grey stripes. Most of the Maltese tigers reported have been of the South Chinese subspecies. The South Chinese tiger today is critically endangered, and the "blue" alleles may be wholly extinct. Blue tigers have also been reported in Korea, home of Siberian tigers. It is suggested that blue tigers possessed two different pairs of recessive alleles - the non-agouti (s/s), and the dilute (d/d) which combine to produce a solid blue-grey colour as found in domestic cats such as the British Blue and Russian Blue.
Black Tiger
A black tiger is a rare colour variant of the tiger and is not a distinct species or geographic subspecies. There are reports and one painting (now lost) of pure black non-striped tigers (true melanistic tigers). Most black mammals are due to the non-agouti mutation. Agouti refers to the ticking of each individual hair. In certain light, the pattern still shows up because the background color is less dense than the colour of the markings.
So-called black tigers are due to pseudo-melanism. Pseudo-melanistic tigers have thick stripes so close together that the tawny background is barely visible between stripes. Such tigers are said to be getting more common due to inbreeding. They are also said to be smaller than normal tigers, perhaps also due to inbreeding or because large black leopards are misidentified as black tigers.
There are reports that one of the three white tigers born in Vandalur zoo in June 2010 seems to have changed its colors — most of its body and legs are now black.
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