Russian soldiers write home while serving on the Eastern Front during World War I, circa 1915. (Photo by Hulton Archive/Getty Images)

Orin Larsen of Inglis, Manitoba hangs on to the horse Dancing Queen in the Bareback event during the Calgary Stampede rodeo in Calgary, Alberta, July 10, 2015. (Photo by Todd Korol/Reuters)

Plants grow on houses in the abandoned fishing village of Houtouwan on the island of Shengshan July 26, 2015. Just a handful of people still live in a village on Shengshan Island east of Shanghai that was once home to more than 2,000 fishermen. Every day hundreds of tourists visit Houtouwan, making their way on narrow footpaths past tumbledown houses overtaken by vegetation. The remote village, on one of more than 400 islands in the Shengsi archipelago, was abandoned in the early 1990s as first wealthy residents then others moved away, aiming to leave problems with education and food delivery behind them. (Photo by Damir Sagolj/Reuters)

In this two photo combination picture, the Eiffel Tower with its usual lighting at left, and after the lighting was switched off at right, at the occasion of the Earth Hour, in Paris, France, Saturday March 28, 2015. This Saturday, 28 March 8:30 p.m. local time, individuals, businesses, cities and landmarks around the world are switching off their lights for one hour to focus attention on climate change. (Photo by Remy de la Mauviniere/AP Photo)

Oded Balilty is an Israeli documentary photographer. He is an Associated Press photographer and won the Pulitzer Prize for Breaking News Photography in 2007. Photo: A Jewish settler struggles with an Israeli security officer during clashes that erupted as authorities evacuated the West Bank settlement outpost of Amona, east of the Palestinian town of Ramallah, in this February 1, 2006, file photo. (Photo by Oded Balilty/AP Photo)

A girl struggles with winds from approaching Typhoon Matmo along the eastern coast of Keelung, northeastern Taiwan, Tuesday, July 22, 2014. (Photo by Wally Santana/AP Photo)

Trevor Olson, from Minnesota, dressed as the character “Joker”, poses for a photograph at New York's Comic Con convention, October 9, 2014, in New York City. The event draws thousands of costumed fans, panels of pop culture luminaries and features a sprawling floor of vendors in a space equivalent to more than three football fields in Javits Center. (Photo by Shannon Stapleton/Reuters)

Sports Finalist – Ian MacNicol. Michalina Kwasniewska of Poland competes in the Women's high jump during day one of The European Athletics U23 Championships 2013 on July 11, 2013 in Tampere, Finland. (Photo by Ian MacNicol/Agence France-Presse)