These powerful images capture the spear-wielding tribes of Papua new Guinea who believe they are possessed with the spirit of the crocodile. They show how the Kangunaman clansmen scar their backs to resemble reptile scales while the Huli Wigmen wear elaborate headdresses to signal they are ready for battle. (Photo by Trevor Cole/Media Drum World)

First prize. Taken over Bali Barat National Park, Denpasar, Bali. Made with a GoPro Hero 2 camera. (Photo by Capungaero)

Spectators dressed as leprechauns attend St Patrick's Day parade in Dublin on March 17, 2014. (Photo by Peter Muhly/AFP Photo)

Kea are the only true alpine parrots in the world and thrive as cunning opportunists in the freezing conditions of the Southern Alps. Kea are thought to have developed their wide array of food-finding strategies during the last great ice age, where they learned to adapt using their unusual powers of curiosity. (Photo by Tom Walker/BBC Pictures/The Guardian)

A participant runs towards the waters of the North Sea during the annual New Year's plunge event in Ostend, Belgium, January 2, 2016. (Photo by Francois Lenoir/Reuters)

Women look at models standing in the David Hart presentation during Men's Fashion Week, in New York, July 13, 2015. The four-day event by the Council of Fashion Designers of America is the New York debut of Fashion Week: Men's. (Photo by Lucas Jackson/Reuters)

A child falls sleep while people take part in the 35th India Day Parade in New York August 16, 2015. (Photo by Eduardo Munoz/Reuters)