An Iraqi soldier stands guard as a pipeline burns in the background after an explosion 30 kilometers (20 miles) northeast of Tikrit, Iraq, Monday, February 11, 2008. (Photo by Bassem Daham/AP Photo)

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

Tourists pose for a selfie in Cancun, October 13, 2015. Cancun's transformation in the 1970s from a small Caribbean fishing village into a strip of nightclubs and high-rise hotels has reduced biodiversity and polluted water resources as infrastructure struggles to keep up. (Photo by Edgard Garrido/Reuters)

Miniature books and furniture are displayed in the "library" of the Astolat Castle, a 3 metre (9 foot) tall dollhouse, currently on display in New York November 14, 2015. Appraised at $8.5 million, the Astolat Castle, weighs 363 kg (800 pounds) and has 29 rooms, according to local media. (Photo by Lucas Jackson/Reuters)

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 protester jumps on the table in front of the European Central Bank President Mario Draghi during a news conference in Frankfurt, Germany April 15, 2015. (Photo by Kai Pfaffenbach/Reuters)

Some 1,250 students from the Assumption College flip their cards to form an image of Thailand's late King Bhumibol Adulyadej, in his honour, in Bangkok, Thailand, October 28, 2016. (Photo by Athit Perawongmetha/Reuters)