This picture taken on January 25, 2015 shows a participant taking part in an ice water challenge in Zhangjiajie, central China's Hunan province. Participants were required to stay in an ice pond, holding an ice block while eating ice-cream with an electric fan blowing at them. (Photo by AFP Photo/Stringer)

A devotee takes a holy bath at the Balaju Baise Dhara (22 water spouts) during the Baishak Asnan festival in Kathmandu April 4, 2015. Devotees believe that the water from these stone spouts, which is collected from the catchment area of the Nagarjun forest behind the spouts, will cure pains and skin diseases. (Photo by Navesh Chitrakar/Reuters)

Cheng Chen (R), a 27-year-old worker at a state-owned enterprise, poses for a photograph with his nephew who is wearing his home-made Iron Man armour, in Xuzhou, Jiangsu province April 13, 2015. It cost Cheng about 500 yuan ($81 USD) to make the armour, which weighs about 4 kilograms, with plastic boards and LED lights, local media reported. (Photo by Reuters/Stringer)

A resident jumps as he watches strong waves crash into shore as an effect of Typhoon Hagupit in Legazpi, Albay province, eastern Philippines on Sunday, December 7, 2014. Typhoon Hagupit knocked out power in entire coastal provinces, mowed down trees and sent more than 650,000 people into shelters before it weakened Sunday, sparing the central Philippines a repetition of unprecedented devastation by last year's storm. (Photo by Aaron Favila/AP Photo)

Bottlenose dolphins swim over visitors in water tank at the Hakkeijima Sea Paradise aquarium-amusement park complex in Yokohama, southwest of Tokyo, Tuesday, July 21, 2015. Temperatures in Tokyo's metropolitan area neared around 96 degree Fahrenheit, or 35 degree Celsius, on Tuesday. (Photo by Shuji Kajiyama/AP Photo)

A new species of monkey found in the Democratic Republic of the Congo and identified as Lesula (Cercopithecus lomamiensis) is seen in this undated photograph from an article published September 12, 2012 in the science journal PLOS One. The monkey was first seen in 2007 by researchers John and Terese Hart of the Peabody Museum of Natural History at Yale Research Project. The finding of C. lomamiensis represents only the second new species of African monkey to be discovered in the past 28 years, according to the research article. (Photo by Hart J. A., Detwiler K. M., Gilbert C. C./Reuters)

ESA astronaut Samantha Cristoforetti on the International Space Station 3 February 2015 during her Futura mission. Samantha is living and working on the Station as part of the Expedition 42 crew. Picture released on February 10, 2015. (Photo by ESA/NASA)

In this April 2, 2015 photo, dog owner Laura Aquilina strolls with her two year old Rottweiler Brutus, who was recently fitted with prosthetics on all four paws, and is currently learning to use them, near Aquilina's home in Loveland, Colo. Brutus lost all four paws to frostbite as a puppy while under care of a breeder, and Aquilina began caring for him about a year ago. (Photo by Brennan Linsley/AP Photo)