Refugees and migrants try to find a place on an already full train headed for Serbia, near the city of Gevgelija, The Former Yugoslav Republic of Macedonia, on February 24, 2016. Refugees and migrants from Iraq and Syria continue to pass through Macedonia on their way to the European Union. (Photo by Georgi Licovski/EPA)

Sheep are herded during the annual sheep parade through Madrid November 2, 2014. Shepherds parade the sheep through the city every year in order to exercise their right to use traditional routes to migrate their livestock from northern Spain to winter grazing pasture land in southern Spain. (Photo by Susana Vera/Reuters)

Women cover their heads with pans as they walk in a light rain brought by Hurricane Matthew in Port-au-Prince, Haiti, Tuesday, October 4, 2016. Matthew slammed into Haiti's southwestern tip with howling, 145 mph winds Tuesday, tearing off roofs in the poor and largely rural area, uprooting trees and leaving rivers bloated and choked with debris. (Photo by Dieu Nalio Chery/AP Photo)

Members of p*ssy Riot perform in concert during Day For Night festival on December 16, 2017 in Houston, Texas. (Photo by Gary Miller/Getty Images)

A young girl navigates her way around Hampton Court maze in the spring sunshine on May 2, 2009 in London, England. The Hampton Court maze is one of the most famous hedge mazes in the world and was planted between 1689 and 1695 by George London and Henry Wise. (Photo by Dan Kitwood/Getty Images)

An India Christian devotee reenacts the sufferings of Jesus Christ on the occasion of Good Friday in Mumbai, India, Friday, March 29, 2013. Christians all over the world are marking Good Friday, the day when Christ was crucified. (Photo by Rajanish Kakade/AP Photo)

Ary Borges feeds his tiger named Dan at his home in Maringa, Brazil, Thursday, September 26, 2013. Borges is in a legal battle with federal wildlife officials to keep his endangered animals from undergoing vasectomies and being taken away from him. He defends his right to breed the animals and says he gives them a better home than they might find elsewhere in Brazil. (Photo by Renata Brito/AP Photo)

The Northern Lights glow green in a spectacular light show above a field of trees frozen solid with snow. (Photo by Jaak Sarv/Solent News & Photo Agency)