To celebrate the birth of one of the world's rarest monkeys, Taronga Zoo, Australia have released a video of their bright orange new addition.The male Francois' leaf monkey has been named Nangua which means “pumpkin” in Mandarin and was spotted in his mother's arms on November 7.The number of Francois' leaf monkeys has significantly declined due to poaching and habitat loss, making Nangua's birth very unusual.The species also known as Francois' Langurs, are born with their distinctive bright orange colouring so their parents can easily recognise them. The colour gradually changes until it becomes black when the monkey is about one-year-old.