A man walks through the morning mist in a park in Rozzano, near Milan, northern Italy, Thursday, December 17, 2015. (Photo by Antonio Calanni/AP Photo)

An aircraft passes over houses at it lands at Heathrow Airport near London, Britain, December 11, 2015. Picture taken December 11, 2015. (Photo by Neil Hall/Reuters)

The Buddha Dordenma statue overlooks the town of Thimphu, Bhutan, April 16, 2016. (Photo by Cathal McNaughton/Reuters)

In this September 4, 1963, file photo, a police officer carries off a demonstrator holding a Confederate flag after a group of demonstrators protested enrollment of two African-Americans at Ramsay High School in Birmingham, Ala. The Confederate battle flag has been removed from South Carolina's Statehouse grounds, in the wake of the massacre of nine African-Americans, including a state senator, at an historic black church in Charleston in June 2015. (Photo by AP Photo)

New York City, 1974. (Photo by Elliott Erwitt/Harry Ransom Center Collection/Magnum Photos)

In this August 1, 2014 photo provided by the National Park Service are male caribou antlers in the Oolah Valley, likely the result of a grizzly kill as he migrated south for the winter at the Arctic National Park and Preserve in Alaska. The nation's northernmost national park says its new management plan will have to consider the effects of a new industrial road to the mining district of Ambler, the first road that would be constructed within its Maryland-sized boundaries. (Photo by Cadence Cook/AP Photo/National Park Service)

Ja Kang Song, 71, and Ja Hyun Su, 72, dive for shellfish and are the main breadwinners for their families. In South Korea, 45% of the diving women of Jeju are over the age of 70. Routinely diving to depths of 20m and staying under for an average of two to three minutes, the pressure on the body takes its toll and, like many others, burst eardrums have left Ja Hyun Su deaf. Each season, between seven and 10 women die diving the waters around Jeju Island. (Photo by Andy W. Langton/Age International)

The crowd watches as stunt pilots Melissa Pemberton, Jurgis Kairys and Skip Stewart of The Immortals fly past pyrotechnics as they perform at The Australian International Airshow on March 1, 2015 in Avalon, Australia. (Photo by Scott E. Barbour/Getty Images)