About : Melanistic Tigers are black striped tigers which are born purely due to genetic reasons. Increased development of melanin pigment in the body causes black stripes. Melanistic tigers are rarely found in the world. They are commonly called Black Tigers

What is in news : NCBS study of ‘black tigers’ has shed light on genetic mystery

Details :

• Their stripes almost fused together in patches threatening to obliterate parts of their burnished orange coats — nobody believed them at first.
• But an estimated 37% of Panthera tigris in the Similipal Tiger Reserve (in eastern India) are pseudomelanistic, characterised by wide, merged stripes.
• This is the result of a rare mutation in one gene, Transmembrane Aminopeptidase Q or Taqpep, recessively inherited variants of which are responsible for the marks in domestic cats and king cheetahs.
• H454Y is likely absent or extremely rare outside of Similipal
• Two factors are probably driving this change in appearance caused by the rare Taqpep p.H454Y: a founder bottleneck effect when a small subset of a large population, in this case tigers, establishes a new population, and the resulting genetic drift, where chance, more than natural selection, changes how common or rare genetic variants are.
• The population at Similipal Tiger Reserve is small and potentially disconnected from other populations. It is likely that related individuals are mating with each other. That is why the driver of this evolutionary change is likely. But given the small population size, yes, Similipal tigers are undergoing inbreeding

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SIMLIPAL TIGER RESERVE

• Is a national park and a tiger reserve in Mayurbhanj district of Odisha.
• Part of Similipal-Kuldiha-Hadgarh Elephant Reserve popularly known as Mayurbhanj Elephant Reserve.
• Derives its name from the abundance of semul (red silk cotton trees) that bloom here.
• Part of UNESCO World Network of Biosphere Reserves since 2009.
• Park has protected area of 845.70 square kilometres and has some beautiful waterfalls like Joranda and Barehipani.
• Home to 99 royal Bengal tigers and 432 wild elephants.
• Besides it is famous for gaurs (Indian bison), chausingha as well as an orchidarium.