The Handicap principle is an evolutionary hypothesis proposed in 1975 by Amotz Zahavi, explaining how animals may evolve handicapped signals which put the animal at a disadvantage, in order to express biological fitness. The best example of this is the plumage of Peacocks. Although the plumage of the peacock may make the Peacock seem vulnerable to predators, the handicap principle suggests it is a method of signalling their biological fitness to Peahens by surviving this long, despite the disadvantage of a large plumage. Although initially this hypothesis was criticised, it has since gained widespread acceptance by the scientific community.