Beryl Lipton, left, douses Matt Lee during the ice bucket challenge at Boston's Copley Square, Thursday, August 7, 2014 to raise funds and awareness for ALS. The idea is: pay up for charity or get doused. The fund-raising phenomenon is catching on fast, propelled by popular videos of the dunkers and the dunked – including famous athletes and entertainers – posted on social media sites. And the challenges are raising tens of thousands of dollars and immeasurable awareness for causes from ALS to breast cancer to a camp for kids who've lost a father to war. (Photo by Elise Amendola/AP Photo)

A man smokes marijuana during a demonstration in support of the legalization of marijuana in Medellin, May 2, 2015. (Photo by Fredy Builes/Reuters)

Children feed a giraffe at Pairi Daiza wildlife park, a zoo and botanical garden in Brugelette, Belgium, May 25, 2015. (Photo by Francois Lenoir/Reuters)

Soldiers of People's Liberation Army (PLA) Lanzhou Military Region jump through a burning obstacle during a training session at a military base in Tianshui, Gansu province, China, January 6, 2016. (Photo by Reuters/Stringer)

In this Monday, January 18, 2016 photo, Iranian rock climber, Farnaz Esmaeilzadeh, scales a climbing gym in the city of Zanjan, some 330 kilometers (207 miles) west of the capital Tehran, Iran. Esmaeilzadeh, 27, who has been climbing since she was 13, has distinguished herself in international competitions despite the barriers she faces as a female athlete in conservative Iran. (Photo by Ebrahim Noroozi/AP Photo)

Four pillars of light from the 4 Laser Guide Star Facility on ESO's Very Large Telescope (VLT) are shown reaching into the Chilean night sky in this image from ESO Photo Ambassador Fred Kamphues, on September 2, 2016. The lasers are a key part of the adaptive optics system on the VLT. Adaptive optics allows astronomers to drastically reduce the atmospheric distortion present at even the best sites in the world for astronomy, including Paranal in Chile, the home of the VLT. (Photo by F. Kamphues/ESO)

In this photo provided by the RSPCA/Australian Capital Territory, an overgrown sheep found in Australian scrubland is prepared to be shorn in Canberra, Australia, Thursday, September 3, 2015. The wild, castrated merino ram named Chris, yielded 40 kilograms (89 pounds) of wool – the equivalent of 30 sweaters – and sheded almost half his body weight. (Photo by RSPCA ACTvia AP Photo)

A woman holds a hedgehog at the Harry hedgehog cafe in Tokyo, Japan, April 5, 2016. In a new animal-themed cafe, 20 to 30 hedgehogs of different breeds scrabble and snooze in glass tanks in Tokyo's Roppongi entertainment district. Customers have been queuing to play with the prickly mammals, which have long been sold in Japan as pets. The cafe's name Harry alludes to the Japanese word for hedgehog, harinezumi. (Photo by Thomas Peter/Reuters)