People look at a loaded truck that got stuck in a sinkhole on a road in Guilin, Guangxi Zhuang Autonomous Region, January 7, 2015. No injury was reported, according to local media. (Photo by Reuters/Stringer)

Chinese Kazakh eagle hunters sit on horseback as they travel to a local competition on January 29, 2015 in the mountains of Qinghe County, Xinjiang, northwestern China. The festival, organised by the local hunting community, is part of an effort to promote and grow traditional hunting practices for new generations in the mountainous region of western China that borders Kazakhstan, Russia and Mongolia. The training and handling of the large birds of prey follows a strict set of ancient rules that Kazakh eagle hunters are preserving for future generations. (Photo by Kevin Frayer/Getty Images)

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 visitor holds up her toy bunny to the aquarium glass in front of Aurora the Russian polar bear at the Sao Paulo Aquarium in Sao Paulo, Brazil, Thursday, April 16, 2015. (Photo by Andre Penner/AP Photo)

A mother prays for success for her child in the college entrance examinations at a Buddhist temple in Seoul, South Korea, November 12, 2015. About 630,000 students on Thursday sat for the annual exams that could lead them to one of the country's top universities. In South Korea, there is no higher achievement than to be accepted by a prestigious university. As a result, many students prepare for these entrance exams from an early age, often studying up to 16 hours a day for years to take this test. (Photo by Kim Hong-Ji/Reuters)

Graffiti is painted on the bathroom walls at a restaurant in the Williamsburg area of Brooklyn borough in New York, United States, October 1, 2015. Some 2.4 billion people around the world don't have access to decent sanitation and more than a billion are forced to defecate in the open, risking disease and other dangers, according to the United Nations. To mark World Toilet Day on November 19, Reuters photographers captured pictures of toilets in cities, towns and villages around the globe. (Photo by Shannon Stapleton/Reuters)

A flight deck crew prepares to launch a F18 Super Hornet from the deck of the USS Eisenhower off the coast of Virginia, December 10, 2015 in the Atlantic Ocean. US Defense Secretary Ash Carter visited the carrier with India's Minister of Defense Manohar Parrikar to demonstrate US Navy aircraft carrier flight operations. (Photo by Mark Wilson/Getty Images)