White tigers are striking animals, captivating with their distinctive white fur and dark stripes. A common perception is that these majestic creatures roam wild jungles, a notion often fueled by popular culture. However, the true story of white tigers is far more intricate and rooted in genetics rather than widespread natural occurrence.
Are White Tigers a Natural Species?
White tigers are not a distinct species or subspecies of tiger. Instead, they are a color variation of Bengal tigers (Panthera tigris tigris), and historically, have also been reported in other subspecies. Their unique white coat is the result of a rare genetic mutation, rather than a separate evolutionary lineage.
How White Tigers Get Their Color
The striking white coloration of these tigers is caused by a recessive gene. Specifically, it involves a mutation in the SLC45A2 gene. This gene variant primarily inhibits the synthesis of pheomelanin, which is the red and yellow pigment found in orange-colored tigers. However, the mutation has little to no effect on eumelanin, the black and brown pigment, which explains why white tigers retain their characteristic dark stripes. This is not albinism, as albinism involves a complete absence of melanin, resulting in pink eyes and no dark stripes.
Survival Disadvantages in Natural Habitats
The white coat, while visually appealing to humans, presents significant disadvantages for a tiger in its natural environment. Tigers rely heavily on camouflage to ambush their prey, blending seamlessly with the orange and green hues of their jungle and forest habitats. The white fur makes them stand out prominently against such backdrops, hindering their ability to stalk prey undetected. This lack of natural camouflage reduces their hunting success and makes them more easily spotted by potential prey. Furthermore, a conspicuous coat could also make them more vulnerable to other predators.
Where White Tigers Live Now
Due to the survival disadvantages associated with their white coat, white tigers are virtually absent in the wild today. The last known free-ranging white tiger was reportedly shot in 1958. Almost all white tigers alive today reside in captivity. These captive populations are primarily found in zoos and wildlife parks, where they have been selectively bred for their unique appearance. The lineage of most white tigers can be traced back to a single male white Bengal tiger named Mohan, captured in India in 1951. To maintain the white coloration, captive breeding often involves inbreeding, which can lead to various health issues among the animals.