Photos of Edward Snowden, a contractor at the National Security Agency (NSA), and U.S. President Barack Obama are printed on the front pages of local English and Chinese newspapers in Hong Kong in this illustration photo June 11, 2013. Snowden, who leaked details of top-secret U.S. surveillance programs, dropped out of sight in Hong Kong on Monday ahead of a likely push by the U.S. government to have him sent back to the United States to face charges. (Photo by Bobby Yip/Reuters)

A pro-Russian supporter with the Russian national flag on her shoulders takes part in a meeting in Simferopol, March 6, 2014. Crimea's parliament voted to join Russia on Thursday and its Moscow-backed government set a referendum within 10 days on the decision in a dramatic escalation of the crisis over the Ukrainian Black Sea peninsula. (Photo by Vasily Fedosenko/Reuters)

A three-month-old Sumatran tiger cub named “Bandar” shows his displeasure after being dunked in the tiger exhibit moat for a swim reliability test at the National Zoo in Washington, on November 6, 2013. All cubs born at the zoo must take a swim test before being allowed to roam in the exhibit. Bandar passed his test. (Photo by Manuel Balce Ceneta/Associated Press)

The remarkable scene was captured by amateur wildlife photographer Ian Salisbury, 62, at the South Luangwa National park in Zambia. The crocodile grabs hold of the elephant's trunk, but it soon becomes clear that he has bitten off a lot more than he can chew by grabbing the huge beast. Mr Salisbury said the elephant “fled rapidly into the bush” after the attack. (Photo by Ian Salisbury/Caters News)

Girls practice sit-ups during gymnastics lessons at the Shanghai Yangpu Youth Amateur Athletic School in Shanghai, China, on May 4, 2016. China's sports system has been enormously successful since the country returned to the Olympic fold in 1980, culminating with the host nation topping the medals' table at the 2008 Beijing Olympics. And yet, with the Rio de Janeiro Games less than three months away, the system is beginning to break down due to the shifting demographics of a more prosperous nation. (Photo by Aly Song/Reuters)

Hundreds of people pack the Canaveral national seashore's Playalinda Beach as a United Launch Alliance Atlas V rocket, carrying a U.S. Navy communications satellite, lifts off from Complex 41 at the Cape Canaveral Air Force Station, Friday, June 24, 2016, in Cape Canaveral, Fla. The satellite is designed to significantly improve ground communications for U.S. forces on the move. (Photo by Craig Rubadoux/Florida Today via AP Photo)

In this Tuesday July 12, 2016 photo, an elephant is lifted by a crane in an upside down position in Lilongwe, Malawi, in the first step of an assisted migration of 500 of the threatened species. African Parks, which manages three Malawian reserves is moving the 500 elephants from Liwonde National Park, this month and next, and again next year when vehicles can maneuver on the rugged terrain during Southern Africa's dry winter. (Photo by Tsvangirayi Mukwazhi/AP Photo)

Praia du Forte, Bahia. “This was the lead picture for a National Geographic story on Bahia, because it was both mysterious as well as a “geography” picture showing where the slaves arrived from Nigeria. Beach pictures seem like they should be easy to take, but for me they are actually quite difficult. Too easy to fall into cliche. When I saw the kid coming on the horse, I quickly ran to see if I could make something with a woman in a bikini that was not a bikini shot”. (Photo by David Alan Harvey/The Guardian)