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)

Members of the Raskol gang “Dirty Dons 585”, 9 Mile Settlement, Port Moresby. All of these young men committed a set of rapes and armed robberies. The gang members admit that two thirds of their victims are women. (Photo by Vlad Sokhin)

This is one boy's amazing picture diary of his pet rodents doing very human tasks. Colin Mclaughlin, from Maryland, USA, has created a hilarious photo collection of his pet guinea pigs, Chester and Sam. (Photo by Colin Mclaughlin/Caters News)

Meet Booboo, the 2-year-old guinea pig. Her hobbies included eating chicory and posing for pictures. Described optimistically as ‘spirited’ by owner Megan, she can generally be found knocking about with her guinea pig crew, Titi and Teddy. But don’t worry, these gangsta guineas are lovers not fighters (didn’t the chicory give you a clue?). In fact, they’re pretty cerebral, often to be found quietly reading a book, or staring contemplatively into the distance next to a sprig of lavender, that kind of thing.

Revellers celebrate the New Year in Princes Street during Hogmanay street party celebrations in Edinburgh, Scotland January 1, 2015. (Photo by Russell Cheyne/Reuters)

A reveller dressed up as Austrian drag queen and 2014 Eurovision song contest winner Conchita Wurst takes part in New Year's celebrations in Coin, near Malaga, southern Spain, early January 1, 2015. Villagers and revellers dressed up in funny costumes to take part in the New Year's celebration. (Photo by Jon Nazca/Reuters)

Lindsay Mann (L) and Anabella Mowbray kiss as they take photos of themselves laying in the confetti on 7th Avenue in Times Square on New Year's Eve in New York January 1, 2015. (Photo by Carlo Allegri/Reuters)