The giant mural titled “Under the Hand” by Maclaim Crew is visible on a building facade in Kreuzberg district on June 26, 2014 in Berlin, Germany. Berlin, with its long tradition of counter-culture, has become a mecca for street art of all dimensions and messages. (Photo by Sean Gallup/Getty Images)

A Turkana boy herds cows as he carries a rifle in north western Kenya near the town of Kibish inside the Turkana region of the Ilemy Triangle September 26, 2014. The Turkana people have historically clashed over ethnic differences and precious resources such as fishing, pasture and fresh water with other tribes bordering their territory, such as the Dassanach from southern Ethiopia. (Photo by Goran Tomasevic/Reuters)

Soldiers of China's People's Liberation Army (PLA) jump as part of their winter training in temperature of negative 26 degrees Celsius at China's border with Russia in Heihe, Heilongjiang province, December 14, 2015. (Photo by Reuters/Stringer)

Victoria's Secret Angel Martha Hunt celebrates the 2015 What Is s*xy? List in San Diego on September 26, 2015 in San Diego, California. (Photo by Joe Scarnici/Getty Images for Victoria's Secret)

Bridegrooms pose for a photograph as they attend a mass wedding ceremony at Arena Corinthians soccer stadium in Sao Paulo, Brazil, September 26, 2015. According to the event's organizers, at least 400 couples tied the knot during a mass wedding which was organized by the Department of Justice and Citizenship of the state of Sao Paulo. (Photo by Paulo Whitaker/Reuters)

A woman wearing a bikini stands next to fuel pumps as she waits to top up fuel at a petrol station in Kiev, Ukraine, September 26, 2015. One of the largest networks of petrol stations in Ukraine organized a campaign in which anyone who showed up in swimwear at a particular gas station during specified hours would receive free gasoline, according to representatives of the company. (Photo by Valentyn Ogirenko/Reuters)

Humanoid robot bartender “Carl” interacts with guests at the Robots Bar and Lounge in the eastern German town of Ilmenau, July 26, 2013. “Carl”, developed and built by mechatronics engineer Ben Schaefer who runs a company for humanoid robots, prepares spirits for the mixing of cocktails and is able to interact with customers in small conversations. (Photo by Fabrizio Bensch/Reuters)

The head of a decapitated rooster is pictured after a rooster run, during celebrations in honour of San Juan Bautista in San Juan de Oriente town, Nicaragua, June 26, 2015. The rooster runs, where horse-riders try to pull the head off live roosters, symbolize the beheading of John the Baptist. (Photo by Oswaldo Rivas/Reuters)