The white tiger is a captivating and rare variant of the Bengal tiger (Panthera tigris tigris). Its distinctive white coat results from a specific genetic mutation, not indicating a separate species or subspecies.
Historical Natural Habitat
Historically, white tigers were found within the natural range of the Bengal tiger, primarily across the Indian subcontinent. Their ancestral habitat was not characterized by snow or ice, but rather by the diverse environments of India, Nepal, Bhutan, and Bangladesh. These areas included tropical and subtropical forests, dense jungles, grasslands, and marshy regions, such as the Sunderbans.
The presence of white tigers in the wild was rare, occurring naturally about once in every 10,000 tiger births. Records of white tigers in India date back to the 16th century, with notable sightings in the former state of Rewa. Their natural habitat provided ample dense vegetation and water sources, supporting the prey species necessary for their survival.
Current Reality of White Tiger Distribution
Today, white tigers are virtually absent from the wild, with the last known free-ranging individual reportedly killed in 1958. Almost all white tigers currently exist in captivity, primarily within zoos, wildlife parks, and private collections across the globe. An estimated 200 white tigers reside in captivity worldwide, with a significant number, around 100 individuals, found in India.
Their white coat, while striking to humans, offers little camouflage in their natural habitats, making hunting challenging and increasing their vulnerability to prey detection. Consequently, their distribution is almost entirely confined to controlled environments.
The Genetics Behind Their White Coat
The white coat of these tigers is a result of a recessive gene mutation that affects pigment production. Specifically, it involves a change in a single amino acid (A477V) within the SLC45A2 gene, which primarily inhibits the synthesis of pheomelanin, the red and yellow pigment. This means that while the red/yellow coloration is suppressed, eumelanin, the black pigment responsible for their stripes, remains largely unaffected.
This genetic condition is not albinism, as albino animals lack all types of melanin and typically have pink eyes. White tigers, in contrast, retain their black stripes and possess blue eyes. The gene for white coloration is recessive, meaning a tiger must inherit two copies of this gene, one from each parent, to display the white coat. This explains their prevalence in captive breeding programs that perpetuate this rare trait.