A baby rhesus macaque (Macaca mulatta) looks up as it plays with a tiger cub at a zoo in Hefei, Anhui province, August 2, 2012. (Photo by Jianan Yu/Reuters)

A masked Kashmiri protester shouts freedom slogan near burning tires set up as road blockade by protesters in Srinagar, Indian controlled Kashmir, Tuesday, July 19, 2016. The largest street protests in recent years in the disputed region, that left dozens of people dead and hundreds injured erupted more than a week ago after Indian troops killed a popular young rebel leader. (Photo by Dar Yasin/AP Photo)

A visitor feeds a food pellet to a giraffe in the Giraffe Centre in Nairobi, Kenya January 15, 2017. (Photo by Goran Tomasevic/Reuters)

A Thai veterinarian sterilizes a monkey in a bid to control the birth rate of the monkey population in Hua Hin city, Prachuap Khiri Khan Province, Thailand, 15 July 2017. (Photo by Narong Sangnak/EPA/EFE)

A bull rams inmates seated at a card table in the Convict Poker event at the Angola Prison Rodeo in Angola, La., Saturday, April 26, 2014. Those competing in the rodeo have to pass a physical to be deemed strong and healthy enough, and thousands of others work year-round making arts and crafts to sell at the event, according to the prison's athletic director. (Photo by Gerald Herbert/AP Photo)

Clashes break out in the stands during the Euro 2016 Group B soccer match between England and Russia, at the Velodrome stadium in Marseille, France, Saturday, June 11, 2016. (Photo by Thanassis Stavrakis/AP Photo)

Haitians pull a car atop a pushcart in Port-au-Prince, October 11, 1994. The price of gasoline has fallen to about $6 US per gallon since U.S. forces occupied Haiti. Before, gasoline had cost as much as $10 U.S. per gallon. (Photo by Eric Draper/AP Photo)

In this July 24, 2016 photo, a pilgrim takes a bath in a sacred mud pool during the annual Voodoo celebration in Plaine-du-Nord, Haiti, Saturday, July 23, 2016. Pilgrims come to bathe in the mud and make offerings expecting a miracle. (Photo by Dieu Nalio Chery/AP Photo)