A pro-democracy demonstrator fights with a Soviet soldier on top of a tank parked in front of the Russian Federation building on August 19, 1991, after a coup toppled Soviet President Mikhail Gorbachev. The same day, thousands in Moscow, Leningrad, and other cities answered Russian Republic President Boris Yeltsin's call to raise barricades against tanks and troops. (Dima Tanin/AFP/Getty Images)

A girl bathes to cool off herself with water that is leaking from a broken pipe valve on a hot summer day on the outskirts of Ahmedabad, India, May 18, 2015. (Photo by Amit Dave/Reuters)

Protesters take part in “Artists Take Fight Against Police Murders” in New York's Times Square August 13, 2015. (Photo by Brendan McDermid/Reuters)

Praia du Forte, Bahia. “This was the lead picture for a National Geographic story on Bahia, because it was both mysterious as well as a “geography” picture showing where the slaves arrived from Nigeria. Beach pictures seem like they should be easy to take, but for me they are actually quite difficult. Too easy to fall into cliche. When I saw the kid coming on the horse, I quickly ran to see if I could make something with a woman in a bikini that was not a bikini shot”. (Photo by David Alan Harvey/The Guardian)

This photo provided by Steamboat Ski Resort shows hot air balloons that visitors can tour in above the town and mountains in Steamboat Springs, Colo. Wild West Adventures offer continental breakfast, champagne ceremony with flight certificates and courtesy pick-up are included. (Photo by Larry Pierce/AP Photo/Steamboat Ski Resort)

A man poses with a hyena along a street in Lagos, Nigeria November 4, 2008. (Photo by Akintunde Akinleye/Reuters)

Labourers carry a basket packed with vegetables through a wholesale market in Kolkata, India, February 26, 2016. (Photo by Rupak De Chowdhuri/Reuters)