This picture taken on January 26, 2016 shows a monkey sitting on a bench during rehearsal at a monkey training school in a zoo in Dongying, eastern China's Shandong province. Shows featuring performing simians, popular in China and throughout Asia, are expecting a boost in the Lunar New Year of the monkey, which begins on February 8. But they are facing a growing backlash from Chinese people concerned about animal welfare. (Photo by Wang Zhao/AFP Photo)

Del Mar firefighters roll up hose after a day fighting wildfires Wednesday, May 14, 2014, in Carlsbad, Calif. More wildfires broke out Wednesday in San Diego County, threatening homes in Carlsbad and forcing the evacuations of military housing and an elementary school at Camp Pendleton. (Photo by AP Photo)

The Supermoon rises over houses in Olvera, in the southern Spanish province of Cadiz, July 12, 2014. Occurring when a full moon or new moon coincides with the closest approach the moon makes to the Earth, the Supermoon results in a larger-than-usual appearance of the lunar disk. (Photo by Jon Nazca/Reuters)

A young Afghan vendor waits for customers to buy sheep's heads at a roadside stall at the busy market in Kabul on November 29, 2015. (Photo by Wakil Kohsar/AFP Photo)

An elephant “kisses” a visitor during a show at an elephant training school in Xishuangbanna, Yunnan province, April 18, 2015. Some 16 elephants live at the school and give four 30-minute performances everyday for visitors. (Photo by Wong Campion/Reuters)

Four year old Kaleb Stanley (R), from Dublin, reaches up to puncture a giant bubble with the help of his seven year old brother Jacob on London's South Bank on May 9, 2008 in England. (Photo by Peter Macdiarmid/Getty Images)

Riot police walk in the street as a couple kiss on June 15, 2011 in Vancouver, Canada. Vancouver broke out in riots after their hockey team the Vancouver Canucks lost in Game Seven of the Stanley Cup Finals. (Photo by Rich Lam/Getty Images)

Three young women preparing a guy. They are sitting him on a keg labelled “gun powder”. (Photo by Fox Photos/Getty Images). 1929