Participants compete in the Mud Day Race extreme run competition at El Goloso military base, outside Madrid, Spain, June 11, 2016. Thousands of athletes got covered in mud as they celebrated International Mud Day running a 13-kilometer obstacle course on a sunny Saturday with heatwave-like temperatures up to a 29 degrees Celcius (around 84 degrees Fahrenheit). (Photo by Juan Medina/Reuters)

Thailand's Puttita Supajirakul is down on the court after a point during a women's doubles badminton match against the Netherlands at the 2016 Summer Olympics in Rio de Janeiro, Brazil, August 11, 2016. (Photo by Kin Cheung/AP Photo)

Pedestrians have a snowball fight in Times Square following a mandatory shutdown of the streets at 11 p.m. on January 26, 2015 in New York City. New York, and much of the Northeast, is bracing for a major winter storm which is expected to bring blizzard conditions and 10 to 30 inches of snow to the area. (Photo by Alex Trautwig/AFP Photo)

An indigenous woman holds her child while trying to resist the advance of Amazonas state policemen who were expelling the woman and some 200 other members of the Landless Movement from a privately-owned tract of land on the outskirts of Manaus, in the heart of the Brazilian Amazon, in this March 11, 2008 file photo. (Photo by Luiz Vasconcelos-A Critica/Reuters/AE)

“Left behind” children Luo Hongni, 11 (L) and brother Luo Gan,10, carry flowers to be used as feed while doing chores in the fields on December 18, 2016 in Anshun, China. Like millions of Chinese children, the four Luo siblings are being raised by their grandparents in rural China as their parents left to find work in urban areas. (Photo by Kevin Frayer/Getty Images)

A young woman wearing the summer Kimono, “Yukata” watches the goldfishes during the press preview of “Eco Edo Nihombashi Art Aquarium 2014” exhibition in Tokyo on July 10, 2014. The two-month-long goldfish exhibition will starts July 11. (Photo by Toshifumi Kitamura/AFP Photo)

People carry drinks at 80s Bar in Damascus, Syria, March 11, 2016. In Damascus's Old City, just a mile from the battered frontline between government and rebel-held territory, young Syrians smoke, drink beer or soft drinks, and talk about anything but the war. The revival of activity in this once-vibrant quarter is part of efforts to project an air of normality in the Syrian capital, even as the five-year-old war that has killed more than 250,000 people and created 5 million refugees continues to rage nearby. (Photo by Omar Sanadiki/Reuters)

People visit the artwork titled Seven Magic Mountains by artist Ugo Rondinone, Wednesday, May 11, 2016, near Jean, Nev. The artwork was recently completed in the desert south of Las Vegas. (Photo by John Locher/AP Photo)