A boy poses with a butterfly on his face during a photocall to promote the “Sensational Butterflies” exhibition at the Natural History Museum in central London, on March 25, 2013. With around 400 live tropical butterflies and moths living in the temporary facility, visitors will get the chance to see them flying freely as well as looking for emerging butterflies at the hatchery window. Running from March 29 to September 15, 2013, the exhibition is housed in a structure in the museum grounds. (Photo by Leon Neal/AFP Photo)

Runners rest inside Kim Il Sung Stadium in Pyongyang, North Korea on Sunday, April 14, 2013. North Korea hosted the 26th Mangyongdae Prize Marathon to mark the upcoming April 15, 2013 birthday of the late leader Kim Il Sung. (Photo by Alexander F. Yuan/AP Photo)

Members of the Raskol gang “Dirty Dons 585”, 9 Mile Settlement, Port Moresby. All of these young men committed a set of rapes and armed robberies. The gang members admit that two thirds of their victims are women. (Photo by Vlad Sokhin)

Miss USA Alyssa Campanella arrives at the 2nd Annual American Giving Awards at the Pasadena Civic Auditorium on December 7, 2012 in Pasadena, California. (Photo by Gregg DeGuire/WireImage)

Father Christmas hands out presents to children at the Aid And Adoption Society home at Leytonstone. (Photo by Gerry Cranham/Fox Photos/Getty Images). 7th December 1938

A dog and its owner perform a routine in the main arena on Day three of Crufts at the Birmingham NEC Arena on March 10, 2012 in Birmingham, England. (Photo by Dan Kitwood/Getty Images)

Participants climb over a wall at the “Tough Mudder” endurance event series in Arnsberg September 6, 2014. Competitors who took part in the endurance event saw themselves having to overcome various military style obstacles. (Photo by Ina Fassbender/Reuters)

A woman takes part in a “Brave Run” competition in Minsk October 4, 2015. (Photo by Vasily Fedosenko/Reuters)