In this December 18, 2013 photo released by Six Flags Discovery Kingdom, 32 men dressed as Santa Claus ride the 150-foot tall SkyScreamer tower swing ride at Six Flags Discovery Kingdom in Vallejo, Calif. (Photo by Jason Quintos/AP Photo/Six Flags Discovery Kingdom)

A member of the mainly Christian “anti-balaka” (anti-machete) militia trains in the Boeing neighbourhood of Bangui, Central African Republic, on February 24, 2014. (Photo by Fred Dufour/AFP Photo)

Daniel Ricciardo performs alongside Michael Kneightley in an RAAF F/A-18 Hornet at RAAF Base in East Sale, Victoria, Australia on March 12th, 2014. (Photo by Andy Green/Red Bull Content Pool)

Amazing gravity-defying photo manipulations by Ravshaniya, a photographer from Uzbekistan, teeters on the edge of levitation. Photo: Untitled. (Photo by Ravshaniya)

A retrospective of Garry Winogrand's photography is on display at the Metropolitan Museum of Art in New York. It is the first in 25 years of his work. The show was organized by the San Francisco Museum of Art, and the National Gallery in Washington, DC. Photo: New York, 1965. (Photo by Garry Winogrand/The Estate of Garry Winogrand, courtesy Fraenkel Gallery, San Francisco)

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)

Fisherwomen laying barrels with salt in preparation for herring curing, 1937. (Photo by Topical Press Agency)

US marines watch the mushroom cloud from an atomic explosion rise above the Yucca flats, Nevada during a US nuclear weapons test. (Photo by Keystone/Getty Images). USA, 1945