White Tiger

White tigers are distinct for the normal colouration in that they lack the pheomelanin pigment that in normal tigers produces the orange colour. They still produce the pigment, eumelanin, and hence are not considered albino. Compared to normal tigers without the white gene, white tigers tend to be somewhat bigger, both at birth and as fully grown adults.[2] Kailash Sankhala, the director of the New Delhi Zoo in the 1960s, said "one of the functions of the white gene may have been to keep a size gene in the population, in case it's ever needed." Dark-striped white individuals are well-documented in the Bengal Tiger subspecies, also known as the Royal Bengal or Indian tiger (Panthera tigris tigris or P. t. bengalensis), and may also have occurred in captive Siberian Tigers[citation needed] (Panthera tigris altaica), as well as having been reported historically in several other subspecies.[citation needed] Currently, several hundred white tigers are in captivity worldwide, with about one hundred being found in India. Nevertheless, their population is on the increase.