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)

A man from Dinka tribe holds his AK-47 rifle in front of cows in a Dinka cattle herders camp near Rumbek, capital of the Lakes State in central South Sudan December 14, 2013. (Photo by Goran Tomasevic/Reuters)

Dancer Beth Bracegirdle of the Balbir Singh Dance Company practises at the Billingham Forum pool in Billingham, UK on July 20, 2016, ahead of the 52nd Billingham international folklore festival of world dance in August. (Photo by Owen Humphreys/PA Wire)

A Humboldt penguin stands on weighing scales whilst being photographed by members of the press during a photocall at the annual weigh-in at London Zoo in London, Britain, 24 August 2016. Every animal that is in the zoo is weighed and measured and the statistics recorded so the data can be shared with zoos across the world. (Photo by Hannah McKay/EPA)

A dune buggy driver trains before competing in a sand dune drag racing event on January 8, 2016, as part of the Liwa 2016 Moreeb Dune Festival in the Liwa desert, some 250 kilometres southwest of Abu Dhabi. The festival, which attracts participants from around the Gulf region, includes a variety of races (cars, bikes, falcons, camels and horses) or other activities aimed at promoting the country's folklore. (Photo by Karim Sahib/AFP Photo)

A Balinese Hindu blows fire, during a parade carrying Ogoh-ogoh effigies symbolising evil spirits, during a ritual before Nyepi, the day of silence, in Palembang, South Sumatra province, Indonesia March 8, 2016. Nyepi is a day of silence for self-reflection celebrating the Balinese Hindu new year, where people may not use lights, light fires, work, travel nor enjoy entertainment. (Photo by Darren Whiteside/Reuters)

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)

A woman and her dogs stop and look at a store mannequin wearing a dog's head mask outside a fashion shop in Nice, France, May 3, 2016. (Photo by Eric Gaillard/Reuters)