Partially demolished houses stand in the Vila Autodromo slum with the Rio 2016 Olympic Park in the background in Rio de Janeiro, Brazil, February 25, 2016. (Photo by Ricardo Moraes/Reuters)

President Barack Obama watches as Joey Hudy (L), 14, from Phoenix, Arizona pumps the Extreme Marshmallow Cannon he invented, while touring student science fair projects on exhibit in the State Dining Room at the White House February 7, 2012 in Washington, DC. Obama hosted the second White House Science Fair celebrating the student winners of science, technology, engineering and math (STEM) competitions from across the country. (Photo by Molly Riley-Pool/Getty Images)

A Bukusu youth stands covered in mud in preparation for a circumcision ritual in Kenya's western region of Bungoma August 9, 2014. Circumcision rituals, which take place in August, are celebrated amongst some Kenyan tribes as an annual rite of passage into adulthood. (Photo by Noor Khamis/Reuters)

In this picture taken on September 24, 2016, relatives grieve their lost one, an alleged drug user/dealer gunned down by unidentified gunmen in Manila. Philippine President Rodrigo Duterte defended his threat to kill criminals as “perfect” and vowed no let-up in his war on crime, as the death toll surged past 3,700. (Photo by Noel Celis/AFP Photo)

Nino, a ten-year-old toreador apprentice of the French Tauromachy Centre, nicknamed El Nino, touches a practice bull at the bullring of Garons, near Nimes, September 25, 2013. Since 1983, the French Tauromachy Centre in Nimes has trained some 1,000 youths in the art of bullfighting. Twenty of them have gone on to become professional matadors, facing fighting bulls in the arena. Twice a week, students take courses with a matador to learn the movements and gestures of the bullfighter in the ring, but without an animal present. Students train with calves in the surrounding fields during spring, and regularly participate in beginner's bullfights (becerradas) without killing calves. Solal has been taking courses for three years and Nino, for just a year now. Both are normally enrolled in French public schools, but have one thought in mind – bullfighting. They share a passion linked to the city of Nimes, famous for its ferias and bullring. (Photo by Jean-Paul Pelissier/Reuters)

People throw turnips at the Jarramplas as he comes out from the church beating his drum during the Jarramplas Festival on January 20, 2016 in Piornal, Caceres province, Spain. The centuries old Jarramplas festival takes place annually every January 19-20 on Saint Sebastian Day and this year they expect to use more than 20 thousand kilogrames of turnips. Even though the exact origins of the festival are not known, various theories exist including the mythological punishment of Caco by Hercules, a relation to ceremonies celebrated by the American Indians that were seen by the first conquerors, to a cattle thief ridiculed and expelled by his village neighbours. It is generally believed to symbolize the expulsion of everything bad. (Photo by Pablo Blazquez Dominguez/Getty Images)

Chahad, 16, gets groomed at a beauty Salon in Kalak before her wedding party, Iraq February 16, 2017. It's the second marriage to take place in the IDP camps east of the city where tens of thousands are living, having fled the fighting in Mosul. (Photo by Zohra Bensemra/Reuters)

An Indian farmer from Tamil Nadu state wearing a necklace of human skulls representing suicides by agricultural workers takes part in a protest with other farmers in New Delhi on March 15, 2017. Tamil Nadu state farmers protested to demand a profitable price for their agricultral products, and called for the formation of management committee for solving Cauvery river water disputes. More than 200 farmers have committed suicide in Tamil Nadu in recent months following crop failure due to poor rainfall and inadequate water for irrigation. (Photo by Prakash Singh/AFP Photo)