A Sri Lankan leopard is pictured at a zoo in Dehiwala near Colombo on March 3, 2016, on World Wildlife Day. (Photo by Ishara S. Kodikara/AFP Photo)

Female bodybuilders prepare to compete in the “Miss Bikini” category of the NABA/WFF Asia-Seoul Open Championship in Seoul on April 17, 2016. (Photo by Ed Jones/AFP Photo)

A PETA (People for the Ethical Treatment of Animals) activist with her body painted promotes veganism in Bangkok April 21, 2016. (Photo by Jorge Silva/Reuters)

Bison along the Bitterroot Valley's Eastside Highway north of Stevensville, Montana, are covered in snow following a blizzard on November 23, 2010. (Photo by Perry Backus/The Missoulian)

The waning moon sets behind leafless sumac trees on a crisp, clear morning, Thursday, December 15, 2016, in Portland, Maine. Much of the northern Mid-Atlantic and Northeast will stay cold for the next couple of days as the arctic air remains stuck over the northern Appalachians, the National Weather Service said. (Photo by Robert F. Bukaty/AP Photo)

Almost two years old male baby orang-utan Dalai looks on in the zoo in Dresden, Germany, 30 March 2017. Dalai was born to mother Daisy in June 2016. (Photo by Filip Singer/EPA)

In this June 12, 2017 photo, a woman stands in front of a mural on the slope in Central district, Hong Kong. Once known as Victoria after the British queen, Hong Kong island's waterfront formed the core of the British settlement after Hong Kong island was handed over as a colony in 1842. Today as Hong Kong approaches the 20th anniversary of its return to China, it remains a bustling commercial and financial center as well as the location of the main government offices. However, along the streets that angle sharply upward toward the mountains above, a more relaxed pace of life endures. (AP Photo/Kin Cheung)

A horse grazes on railway tracks near the old train station on the the Northeast railroad (Ferrovia do Nordeste) in the city of Missao Velha, Ceara state, northeastern Brazil, October 25, 2016. (Photo by Ueslei Marcelino/Reuters)