Palestinian schoolboys sit in the trunk of a car as they go to school on a rainy day in Khan Younis, in the southern Gaza Strip, October 7, 2015. (Photo by Ibraheem Abu Mustafa/Reuters)

A man drinks at a "colored" water cooler in a streetcar terminal in Oklahoma City, July 1939. (Photo by Reuters/Library of Congress)

People stroll alongside one of the hills of the Tio Pio park in Madrid, Monday, January 25, 2016. The park is a high viewpoint frequented mostly by locals due to its view of the Spanish capital skyline. (Photo by Francisco Seco/AP Photo)

Refugee children play with a stuffed toy at a muddy makeshift camp at the Greek-Macedonian border, near the village of Idomeni, Greece March 15, 2016. (Photo by Alexandros Avramidis/Reuters)

Tibetan boys dressed in traditional attire take part during a function organised by the Tibetan Refugee Community in Nepal,commemorating the 25th Anniversary of the Nobel Peace Prize conferment to exiled Tibetan spiritual leader Dalai Lama and the 66th International Human Rights Day in Kathmandu December 10, 2014. Nepal ceased issuing refugee papers to Tibetans in 1989 and recognizes Tibet to be a part of China. (Photo by Navesh Chitrakar/Reuters)

In this Friday, February 6, 2015 photo, sandhill cranes begin to stir after resting for the night at a roosting location along their winter migration route in Cecilia, Ky. According to counts made by biologists with the Kentucky Fish and Wildlife Resources, about 12,000 of the birds have stopped in Cecilia this week during their winter northward migration on their way to their nesting grounds in the Great Lakes region. (Photo by David Stephenson/AP Photo)

A poster for the IMAX presentation of “The Hunger Games: Catching Fire” (left), and a teaser poster for “The Hunger Games: Mockingjay, Part I”, both created by the Los Angeles-based design firm IGNITION. Both are nominated for the 2014 Key Art Awards in the category of Theatrical Domestic One-Sheet. The Hollywood Reporter's annual competition for the best in film and TV advertising honors some of the most creative imagery used in movie posters. Here is a selection of some of this year's nominees. (Photo by Key Art Awards 2014)

United States Coast Guard Academy Cadets Second Class Aurimas Juodka, left, and Sheila Bertrand get in the face of “swab” Kevin Lennox as Bravo Company finishes at the barber shop and mailroom during R-Day, the reporting-in day that marks the beginning of the 7-week “Swab Summer” for the class of 2018 Monday, June 30, 2014, in New London, Conn. About 250 prospective cadets, Swabs, start the program designed to indoctrinate them to the military life of the academy and at the end will be accepted into the corps of cadets. (Photo by Sean D. Elliot/AP Photo/The Day)