A white tiger cub born at the Vandalur zoo in Chennai, India is turning black. From The Telegraph:
Biologists believe a large presence of melanin, the dark skin pigment, is the likely reason for its unusual colouring.
Tigers’ skin colour is determined by the presence of black and yellow pigments. In most tigers, the colour yellow dominates over black to give them their characteristic colouring.
“In this cub, the reverse has happened – black is the dominant colour,” senior zoo biologist Dr Manimozhi told The Times of India.
“It is the dominance of yellow pigment that enables tigers to survive in the wild,” he added. “In fact, this is the reason why most white tigers are found only in zoos and not in the wild,” Dr Manimozhi said.