A Cambodian girl goes through the garbage dump looking for things to recycle in order to survive July 26, 2003 in Phnom Penh, Cambodia. Rampant corruption in this impoverished country has lead to extreme poverty with many Cambodians living below the poverty line. (Photo by Paula Bronstein/Getty Images)

A US Marine feeds an orphan kitten found after a heavy mortar barrage near “Bunker Hill” during the Korean War. (Photo by Sgt Martin Riley/Getty Images). 1953

A tiger cub has a short chat with a chimp. (Photo by Ian Tyas/Keystone Features/Getty Images). 27th November 1979

Winston Leonard Spencer Churchill (1874–1965), British Statesman and Prime Minister inspecting the boys from a training ship. (Photo by Hulton Archive/Getty Images). 1912

Getting her tongue pierced was “exciting and scary” says a teen who succumbed to pressure from her best friend in Austin, Texas, February 22, 2008. This image is featured in National Geographic's exhibition “Women of Vision: National Geographic Photographers on Assignment”, on view at the Palm Beach Photographic Centre, Jan. 22 - Mar. 22, 2015. (Photo by Kitra Cahana/National Geographic)

Brett Throckmorten of Barnes Bullets shows Logan Wingo how to sight down an electronic rifle in the trade booth area during the National Rifle Association's annual meeting in Nashville, Tennessee, April 11, 2015. (Photo by Harrison McClary/Reuters)

The 26th annual National Geographic Traveler Photo Contest is now accepting submissions. Official categories include: “Travel Portraits”, “Outdoor Scenes”, “Sense of Place” and “Spontaneous Moments”. The contest is accepting entries until June 30. Photo: “Forest lights”. Aurora Borealis over the forest of the Pyhae Luosto National Park, Finland. (Photo and caption by Nicholas Roemmelt/National Geographic Traveler Photo Contest)

A general view of Hong Kong's business district is seen Thursday, August 1, 2013. (Photo by Vincent Yu/AP Photo)