The species found in the Indian subcontinent is the Bengal tiger: undoubtedly an orange tiger with black stripes. However, some photos flooding on global social media platforms have indeed taken the Internet by storm. This includes photos of a golden tiger from Kaziranga National Park.
Despite claims from netizens, they are indeed legitimate. Agreed, due to some genetic mutations, albeit abnormalities, these individuals look nothing like the Bengal tiger. The latest tiger ‘mutants’ to grab the attention of the general public are the pseudo-melanistic and golden tigers. The former was recently camera trapped for the first time in the wild in July 2022, from Simlipal Tiger Reserve in Odisha. The golden tiger was first photographed in July 2020 at Kaziranga National Park.
One would consider the occurrence of such individuals a zoological marvel. However, the truth is far from being a celebratory moment. Pseudo-melanistic and golden tigers, in reality, suffer from conditions that could drastically affect their future generations. It is in fact indicative of high inbreeding caused by habitat fragmentation. Despite a 40% increase in global tiger population, there is still a lot of work to be done!
Pseudo Melanistic Tigers
The pseudo-melanistic tiger is characterised by wide and closely-spaced black stripes, covering a large area of its body. According to research conducted by National Centre for Biological Sciences, Bangalore, this fur pattern occurs due to a single base mutation in transmembrane aminopeptidase Q (Taqpep), giving rise to a high melanin deposition. This phenomenon is supported by the non-agouti mutation, a recessive gene mutation which prevents the formation of light and dark bands in the hair, making the hair black due to melanin production.
Termed ‘pseudo’-melanistic tigers, since they can never truly be completely black, these mutants were first allegedly introduced to the public in as early as 1773, through a water colour painting by James Forbes. However, claims of sightings of the black tiger were shut down, due to the high possibility of these black tigers actually being black leopards. Finally, a remarkable event occurred when a pseudo-melanistic tiger was camera trapped for the first time ever in STR in July 2022.
Pseudo-melanistic individuals are nowhere to be found in the wild but at the STR in Odisha. Individuals are also found captive in zoos and wildlife parks, like at the Nandankanan Zoo, Bhubaneshwar, Arignar Anna Zoological Park, Chennai and Bhagwan Birsa Biological Park, Ranchi.
What about the Golden Tiger?
The golden tiger, another type of mutant of the Bengal tiger, made headlines in July 2020, when a female named Kazi-106F was photographed for the first time in the Kaziranga National Park in Assam.
The golden tiger also has a history of being captured through various camera traps, signifying its natural occurrence in the wild. Nevertheless, this mutant also lives in zoos around the world. The golden tiger also owes its unique coat to the occurrence of a recessive gene called ‘wideband’, which reduces melanin production during the cycle of hair growth. Thus, the agouti mutation is responsible for the blond or golden skin, while the orange stripes appear due to the ‘tabby’ mutation, found in other felids, too.
What are some tigers melanistic?
Black and golden tigers basically exist as they both possess a recessive gene which is expressed due to the absence of a dominant gene to suppress it. When two individuals with dominant traits breed, recessive genes are masked, but when two individuals with recessive genes breed, the recessive gene is expressed and such is the case for these two tiger mutants.
Inbreeding, the practice of breeding between two related individuals, in animals takes place naturally due to external environmental conditions such as habitat degradation, population fragmentation and loss of connectivity with other individuals of the same species. An isolated population must thus inbreed for survival. This new, small group is known as the founder population, while the sudden decrease in population is known as the bottleneck effect, causing strain within this group.
Apart from natural inbreeding, the malpractice of breeding of animals by humans is not new. Molecular biology is a fascinating branch and its applications are useful when dealt with in the correct fashion. However, this is not the case with the occurrence of pseudo-melanistic and golden tigers.
Why is India’s Golden Tiger a concern?
A rare phenomenon in the wild, the birth of black and golden tigers is fairly common when bred in captivity. This is due to the action of inbreeding. There is a much higher chance of the inbred offspring carrying recessive genes, thus appearing either black or golden or even white! Inbreeding not only results in physical alterations but also in internal abnormalities. Inbred animals are often more prone to disorders such as strabismus (misaligned eyes), limb malformations, heart disease, and reduced fertility. Consequently, extinction rates are high for species whose individuals are evidently not healthy.
To find a solution to the concern of the appearance of black and golden tigers, a certain action must be taken to prevent population isolation of a species. This culminates into environmental conservation and ecosystem restoration. By rehabilitating the natural habitat of the tiger, we would be able to save it from species isolation and thus inbreeding depression. This will also help prevent human tiger conflict.
Finally, it’s up to humans to either construct or destruct the way for the survival of a species. It’s time to bring up the question: do humans have the right to meddle with nature and use science for their selfish gains?
Written by: Shreya Patankar
Conclusion
Help us Help Them! Think Wildlife Foundation is a non profit organization with various conservation initiatives. Our most prominent campaign is our Caring for Pari intiative. Pari is a rehabilitated elephant at the Wildlife SoS Hospital. 25% of the profits from our store are donated to the elephant hospital for Pari. Other than buying our wonderful merchandise, you could donate directly to our Caring For Pari fundraiser.