A rescue helicopter is shown at the Mount Everest south base camp in Nepal a day after a huge earthquake-caused avalanche killed at least 17 people, in this photo courtesy of 6summitschallenge.com taken on April 26, 2015 and released on April 27, 2015. Rescue teams, helped by clear weather, used helicopters to airlift scores of people stranded at higher altitudes, two at a time. (Photo by Reuters/6summitschallenge.com)

Artist Heather Dewey-Hagborg's 'Stranger Visions', comprising of 3D printed faces extracted from DNA taken from discarded cigarette butts and chewing gum, is displayed at the Big Bang Data exhibition at Somerset House on December 2, 2015 in London, England. The show highlights the data explosion that's radically transforming our lives. It opens on December 3, 2015 and runs until February 28, 2016 at Somerset House. (Photo by Peter Macdiarmid/Getty Images for Somerset House)

Caporal dancers perform during the carnival celebrations in Oruro, Bolivia, Saturday February 14, 2015. The Carnival of Oruro which is a religious festival dating back more than 2000 years in an ongoing pagan-catholic blend of religious practice in the region, and is one of UNESCO's Masterpieces of the Oral and Intangible Heritage of Humanity. (Photo by Juan Karita/AP Photo)

A model presents a creation by French designer Jean Paul Gaultier as part of his Spring/Summer 2015 women's ready-to-wear collection during Paris Fashion Week September 27, 2014. (Photo by Gonzalo Fuentes/Reuters)

A man lies on the floor during a ritual at the Sorte Mountain on the outskirts of Chivacoa, in the state of Yaracuy, Venezuela October 10, 2015. One long night every year in a mountainous rainforest in Venezuela, hundreds gather to dance on red-hot embers, enter trance-like states, and worship an ancient goddess known as Maria Lionza. Those who travel to the mountain known as Sorte in central Venezuela are practitioners of a cult that is built on local indigenous traditions. (Photo by Marco Bello/Reuters)

A man performs ablution using water at an old fountain before performing prayers in the old city of Algiers Al Casbah, Algeria December 3, 2015. The Algiers Casbah is a UNESCO World heritage site that includes the Sidi Ramdane mosque and former fortress, 10 centuries old. Decay from the passing years, as well as earthquake damage in 2003, leads some to consider a move to modern apartments with financial backing from the government. Others refuse to leave a neighbourhood they have called home for decades. (Photo by Zohra Bensemra/Reuters)

People climb on an artificial ice-wall in Liberec, about 100 km north of Prague, Czech Republic, Saturday, January 23, 2015. The wall was prepared in a former quarry just near the centre of the city. (Photo by Radek Petrasek/CTK via AP Photo)

An old locomotive train that was used for transporting coal is preserved as a monument at Ny-Alesund, in Svalbard, Norway, October 11, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. (Photo by Anna Filipova/Reuters)