A climber walks on the ridge beneath the eastern peak of the Gamsberg (2385 meters above sea level) near Grabs, Switzerland, Friday, October 3, 2014. (Photo by Gian Ehrenzeller/AP Photo/Keystone)

A police officer walks along a street of the burning village of Smolenka near Chita on Monday, April 13, 2015. Russian authorities say out-of-control agricultural fires have killed at least 15 people, injured hundreds more and destroyed or damaged more than 1,000 homes in Siberia. The fires were started by farmers burning the grass in their fields, but spread quickly because of strong winds. (Photo by Evgeny Yepanchintsev/AP Photo)

A mass pillow fight in Trafalgar Square in central London on April 5, 2014 on International Pillow Fight Day. (Photo by Jane Scanlan)

Among the fish populations that could be harmed by the Xayaburi dam in Laos is the critically endangered Mekong giant catfish, considered by the Guinness Book of World Records to be the world’s largest freshwater fish. The fish, which grows to 650 pounds and about 10 feet long, is only found in the Mekong River. It is migratory, moving between downstream habitats in Cambodia upstream to northern Thailand and Laos each year to spawn. Some experts fear the Xayaburi dam could block the migration and drive the giant catfish to extinction. (Photo by Courtesy of Zeb Hogan/University of Nevada, Reno)

Two Hindu holy men of the Juna Akhara sect are being take on a motorcycle by their teacher as they got delayed for a rituals that are believed to rid them of all ties in this life and dedicate themselves to serving God as a “Naga” or naked holy men, at Sangam, the confluence of the Ganges and Yamuna River during the Maha Kumbh festival in Allahabad, India, Wednesday, February 6, 2013. The significance of nakedness is that they will not have any worldly ties to material belongings, even something as simple as clothes. This ritual that transforms selected holy men to Naga can only be done at the Kumbh festival. (Photo by Rajesh Kumar Singh/AP Photo)

Final match Soccer Humanoid Kid Size between DARwIn vs. AUTMan at the World Championship finals of RoboCup 2013 in Eindhoven (NL). (Photo by Bart van Overbeeke)

A worker spreads paddy crop for drying in a rice mill complex on the outskirts of Ahmedabad February 3, 2011. (Photo by Amit Dave/Reuters)

Sniper rifles sit on display for sale at the “Ready Gunner” gun store in Provo, Utah, U.S., June 21, 2016. (Photo by George Frey/Reuters)