“The Challenge!” Young boy relishes in a game of tug of war before school. Photo location: Lake Titicaca, Peru. (Photo and caption by Paul Heyman/National Geographic Photo Contest)

A wolf-like robot “Super Monster Wolf” stands beside a rice field to drive away wild animals that cause damages to crops in Kisarazu, Chiba prefecture, on August 25, 2017. The agricultural coopetative association JA Kisarazu-shi introduced the 65cm-long and 50cm-high robot recently on a trial basis which can detect wild animals such as boars and deers with an infrared ray sensor when they approach and intimidates them, flashing the red LED eyes and blaring 48 types of sounds including a wolf growl and human voice. (Photo by Toru Yamanaka/AFP Photo)

A man impersonating Kim Jong-un gestures during the athletics at the Rio 2016 Olympic Games at the Olympic Stadium in Rio de Janeiro on August 18, 2016. (Photo by Johannes Eisele/AFP Photo)

Students exercise in body training at Bishan Vocational Education Center in Chongqing, southwest China, January 13, 2016. These students were trained to be stewardesses of the high-speed train. (Photo by Xie Jie/Xinhua)

An election poster calling for the legalisation of marijuana and featuring internet meme “Grumpy Cat” hangs outside the Pirate Party's campaign headquarters in Berlin on August 16, 2013. The Pirates, who to everyone's surprise were elected into Berlin's regional parliament in September 2011, are trying to capitalise on their recent electoral gains in upcoming parliamentary elections, running on a platform of transparency in government. Germany goes to the polls on September 22, 2013. Placard reads: “Hurry up, my dope is everything”. (Photo by John Macdougall/AFP Photo)

Members of the Dominican Armed Forces participate in a commemorative act on the 170th anniversary of national independence at the esplanade of Santo Domingo, on February 27, 2014. (Photo by Orlando Barria/EPA)

A fox runs out onto the pitch before the start of the second half. Celtic League 2012/13, Round 19, Leinster v Ulster, RDS, Ballsbridge, Dublin, March 30, 2013. (Photo by Paul Mohan)

A local boy plays football on Iracema Beach on June 11, 2014 in Fortaleza, Brazil. (Photo by Robert Cianflone/Getty Images)