In this February 2, 2015 photo, tourists jump as they pose for a picture, after disembarking from the Ocean Nova cruise ship, on King George Island, Antarctica. This tourist season, which runs November through March, more than 37,000 visitors are expected to walk on the coldest continent on Earth, about 10 percent more than the year before. (Photo by Natacha Pisarenko/AP Photo)

A gaucho is unseat by a wild horse during the annual celebration of Criolla Week in Montevideo, March 30, 2015. Throughout Easter Week, “gauchos”, the Latin American equivalent of the North American cowboy, from all over Uruguay and neighboring Argentina and Brazil will visit Montevideo to participate in the Criolla Week to win the best rider award. The competition is held from March 29 to April 5 this year. (Photo by Andres Stapff/Reuters)

In this photo taken on Saturday, April, 4, 2015, a bear chews on a corncob at a shelter that attracts hundreds of visitors and volunteers from around the world every year, in Kutarevo, Croatia. Over a decade ago, Ivan Crnkovic-Pavenka, a retired Croatian social worker decided to help bears become “ambassadors of the wilderness” among people and set up a unique shelter for brown bears in the idyllic mountain village of Kutarevo in central Croatia, where eight bears currently live in two huge enclosures. (Photo by Amel Emric/AP Photo)

Riot policemen stand in formation during street protests against the decision made by Burundi's ruling National Council for the Defence of Democracy-Forces for the Defence of Democracy (CNDD-FDD) party to allow President Pierre Nkurunziza to run for a third five-year term in office, in the capital Bujumbura, April 26, 2015. Police in the Burundian capital used water cannon and tear gas on Sunday to disperse protesters demonstrating against Nkurunziza seeking a third term, witnesses said, after the government banned protests for or against the move. (Photo by Thomas Mukoya/Reuters)

An approximately 8 year-old male orangutan named Siamang reacts under the influence of tranquilizer as it's being prepared to be released into the wild at a rehabilitation center in Kuta Mbelin, North Sumatra, Indonesia, Friday, July 10, 2015. The orangutans at the center were mostly rescued from palm oil plantations or confiscated from homes where they were kept as pet animals. Orangutan populations in Indonesia's Borneo and Sumatra island are facing severe threats from habitat loss, illegal logging, fires and poaching. Conservationists predicted that without immediate action, orangutans are likely to be the first great ape to become extinct in the wild. (Photo by Binsar Bakkara/AP Photo)

A sinkhole is seen on the shore of the Dead Sea near Kibbutz Ein Gedi, Israel July 27, 2015. The Dead Sea is shrinking, and as its waters vanish at a rate of more than one meter a year, hundreds of sinkholes, some the size of a basketball court, some two storeys deep, are devouring land where the shoreline once stood. (Photo by Amir Cohen/Reuters)

Job seekers carry a woman who fainted at the Indonesia Spectacular Job Fair 2015 at Gelora Bung Karno stadium in Jakarta August 12, 2015. Indonesia's gross domestic product grew at 4.67 percent in the second quarter, its slowest pace in six years. Since he took office last October, Widodo's government has passed a raft of measures aimed at boosting industry and consumption that have been criticized by investors as protectionist. (Photo by Reuters/Beawiharta)

Attendees visit the Ford booth during Auto China 2018 show held in Beijing, China, Wednesday, April 25, 2018. Auto China 2018, the industry's biggest sales event this year, is overshadowed by mounting trade tensions between Beijing and U.S. President Donald Trump, who has threatened to hike tariffs on Chinese goods including automobiles in a dispute over technology policy. (Photo by Ng Han Guan/AP Photo)