A little girl takes a picture of a lion in the zoo in Frankfurt, Germany, Tuesday, September 13, 2016. (Photo by Michael Probst/AP Photo)

A woman cries after her husband was shot dead by unidentified gunmen riding motorcycles in Manila, Philippines late October 10, 2016. According to police reports, around 2,300 people have been killed in Philippine President Rodrigo Duterte's war against illegal drugs. The figure was revised by the police from an original tally of around 3,600 deaths. (Photo by Damir Sagolj/Reuters)

A person viewing the Northern lights over the lava landscape, Reykjanes Peninsula, Iceland. (Photo by Arctic-Images/Getty Images)

A Virgin Atlantic passenger plane flies in the sky with the moon seen in the background, in London, Britain January 19, 2016. (Photo by Toby Melville/Reuters)

Yala national park, Sri Lanka. Category: Action. “The daylight was fading and I was scanning the bush for a leopard. Then, I saw this garden lizard and a common bronzeback snake in the road. When the snake struck, the lizard performed amazing acrobatics to avoid it. The snake didn’t enjoy the extra attention from the crowd of jeeps. The distraction gave the lizard the chance to live another day”. (Photo by Sajith Buddikha Withanage/National Geographic Traveller UK)

Models struggle against strong wind before the rehearsal of Christian Dior's Haute Couture Spring-Summer 2017 live show to celebrate Dior's new flagship store at the rooftop of Ginza Six mall in Tokyo, Japan, April 19, 2017. (Photo by Toru Hanai/Reuters)

Racegoers in fashionable hats attend Ladies Day at Cheltenham Festival on March 15, 2017 in Cheltenham, England. (Photo by David Davies/PA Wire)

A child dressed as a Roman centurion poses during a parade to mark the anniversary of the foundation of Rome in 753 BC, on April 23, 2017 in Rome. (Photo by Alberto Pizzoli/AFP Photo)