Tong Jieping, 44-year-old mentally disabled patient, is chained by his foot inside his room, in Qunxing village of Wangjiang county, Anhui province, China, July 14, 2015. Tong was diagnosed mentally ill when he was in his 20s. His parents, both in their 70s, could not afford the medical treatments so they had to lock him up in chains to prevent him from running away, according to Tong's family. (Photo by Reuters/Stringer)

Looters scramble in Philipsburg, St. Maarten, Sunday September 10, 1995 for goods in the Ram's department store, which contained mostly food and liquor. No attempts are currently being made by Dutch troops on the island to stop the looting, since few relief supplies have arrived in St. Maarten, which was ravaged on Tuesday by Hurricane Luis. (Photo by John McConnico/AP Photo)

“Environmental Migrants: The Last Illusion” by photographer Alessandro Grassani, documents the life of people in Kenya, Mongolia and Bangladesh who migrate to escape environmental stresses to the city of their own countries in hopes for a better life. Here: Asia, Mongolia, March 27, 2011. A view of Ulaan Baator over the shoulder of a slumbering drunk. Alcoholism is a huge problem in the city, home to almost half of Mongolia's people. The capital's population has doubled in the past two years. High levels of unemployment and poverty await herders who abandon rural areas and arrive in the city, illiterate and untrained in any skills necessary for urban jobs. (Photo by Alessandro Grassani)

Germany's Angelique Kerber reacts after popping a bottle of champagne, a day following her win in the final match at the Australian Open tennis tournament, at the Government House in Melbourne, Australia, January 31, 2016. (Photo by Issei Kato/Reuters)

An artist from the state of Telangana reacts to the camera as they wait for their turn to perform during a media preview displaying a glimpse of culture of different parts of India, in New Delhi, India, Thursday, January 22, 2015. The tableaux will be part of the Indian Republic Day parade on Jan. 26. (Photo by Altaf Qadri/AP Photo)

Women wearing prosthetic legs participate in a public photo session at the Hasselblad and Profoto booth, during the CP+ camera and imaging equipment trade fair in Yokohama south of Tokyo, February 14, 2015. Japanese prosthetist Fumio Usui inspired the event after collaborating with photographer Takao Ochi in the book project “Amputee Venus” that portrays 11 Japanese women with artificial legs, local media reported. (Photo by Thomas Peter/Reuters)

A handout picture provided by Solar Impulse on 18 March 2015 shows the Swiss solar-powered plane Solar Impulse 2, HB-SIB, taking off with Swiss explorer Andre Borshberg on board for the third leg Ahmedabad to Varanasi, of the Round-The-World, in Ahmedabad, India, 18 March 2015. Swiss explorers Bertrand Piccard and Andre Borschberg attempt to circumnavigate the world flying with an aircraft, with a 72 metres wingspan, powered only by solar energy without a drop of fuel. (Photo by EPA/Solar Impulse)

“Diver in Magic Kingdom”. Green Lake (Grüner See) is located Tragöss Austria. In spring snowmelt raises the lake level about 10 meters. This phenomenon, which lasts only a few weeks covering the hiking trails, meadows, trees. The result is magical to watch diving landscapes. Photo location: Grüner See at Tragöss, Austria. (Photo and caption by Marc Henauer/National Geographic Photo Contest)