A 20-year-old Japanese macaque monkey named Monday scratches her eyes while suffering an allergy to pollen from the cedar tree at Awajishima Monkey Centre on March 17, 2013 in Sumoto, Japan. Many monkeys are suffering the effects of hay fever at this time of the year, with the typical symptoms being the same as with humans. According to Awajishima Monkey center this year hay fever is higher than last year, the pollen season is from February to April. (Photo by Buddhika Weerasinghe)

Student protestors, including one girl with a camera, struggle with soldiers from the Chinese Army, the PLA. Tiananmen Square, 1989. (Photo by Jeff Widener/Associated Press)

A shot of Pu'uo crater, the main source of lava from Kilauea, taken from a helicopter in Kilaura, Hawaii. (Photo by Kirk Aeder/Barcroft Media)

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)

Two men help each other cross a street covered in deep mud in Copiapo, Chile, Thursday, March 26, 2015. Unusually heavy thunder storms and torrential rains that began on Tuesday have blocked roads, caused power outages and affected some 600 people on this normally dry region. (Photo by Aton Chile/Marcelo Hernandez/AP Photo)

The Dora the Explorer balloon moves through Times Square during the Macy's Thanksgiving Day parade Thursday, November 23, 2006 in New York. (Photo by Frank Franklin II/AP Photo)

Iraqi Kurdish refugees wait with children in Cukurca refugee camp in Turkey April 8, 1991. Reuters photographers have chronicled Kurdish refugee crises over the years. In 1991 Srdjan Zivulovic documented refugees in Cukurca who had escaped a military operation by Saddam Hussein's government in Iraq aimed at “Arabising” Kurdish areas in the north. Hundreds of thousands fled into Turkey and Iran. Images shot in recent months show familiar scenes as crowds of people flee Islamic State militants in Syria. There are as many as 30 million Kurds, spread through Turkey, Iraq, Syria and Iran. Most Kurds are Sunni Muslims, but tend to feel more loyalty to their Kurdishness, rather than their religion. (Photo by Srdjan Zivulovic/Reuters)