Workers carve ice art works at Harbin Ice and Snow World one day before the 32th Harbin International Ice and Snow Festival in Harbin city, China's northern Heilongjiang province, 04 January 2016. The festival will run from 05 January to 05 February. (Photo by Wu Hong/EPA)

World Champion Matthias Dolderer of Germany flies over the Horseshoe Bend near Lake Powell in Page, United States during the transfer flight from Indianapolis to Las Vegas to prior the final stage of the Red Bull Air Race World Championship on October 12, 2016. (Photo by Predrag Vuckovic/AFP Photo)

Jazmin, 6, sister of Jose Luis, receives Isoniazid Preventive Therapy in Carabayllo in Lima, Peru July 14, 2016. At least 30,000 Peruvians are infected with tuberculosis, an ancient disease that killed 1.8 million globally last year, more than AIDS-related and malaria deaths combined. Partners in Health, a Boston-based non-profit that works with Peru's health ministry, offers a simple solution. It trains community volunteers to tend to tuberculosis sufferers in their homes – ensuring patients take medicine daily and helping them navigate the public health bureaucracy. (Photo by Mariana Bazo/Reuters)

Rare images of wild tigers in Bhutan, captured by camera traps, show tigers and other animals using high-altitude wildlife corridors which are lifelines to isolated tiger populations and critical to genetic diversity, conservation and growth. Here: A wild Bengal tiger (Panthera tigris tigris) captured on a camera trap in corridor eight at an altitude of 3,540 metres in Trongsa, Bhutan. (Photo by Emmanuel Rondeau/WWF UK/The Guardian)

Participants wrestle while riding yaks during Kyrgyz national horse games and festival near the Tulpar-Kul in the Chon Alai range, some 3500 metres (11483 feet) above sea level, Osh region, Kyrgyzstan, July 25, 2015. (Photo by Vladimir Pirogov/Reuters)

A sofa floats in the polluted waters of Jacarepagua Lagoon, during a press tour in Rio de Janeiro, March 9, 2015. A press tour was organised by biologist Mario Moscatelli, to call attention to pollution on the waters of the lagoons which surround the Rio 2016 Olympic Park. (Photo by Ricardo Moraes/Reuters)

A visiitor bungee jumps during an outdoor festival to celebrate German Unity Day on the 21st anniversary of German reunification on October 3, 2011 in Berlin, Germany. German Unity Day is a national holiday and marks the day West Germany and East Germany were reunited in 1990 following the collapse of the Iron Curtain. (Photo by Adam Berry/Getty Images)

The world's biggest wild animal farmer, Carr Hartley of Rumuruti in Kenya, sells animals to zoos, circuses and film companies. (Photo by Maxim Ruston/BIPs/Getty Images). November 1956