NATO and U.S. flags flutter as U.S. Air Force F-22 Raptor fighter flies over the military air base in Siauliai, Lithuania, April 27, 2016. (Photo by Ints Kalnins/Reuters)

A woman carrying a basket of papayas while walking through a vegetable market in Bangkok, Thailand November 11, 2011. (Photo by Kerek Wongsa/Reuters)

A man poses in front of a portrait of late Chinese Chairman Mao Zedong during the opening of an exhibition of Mao related art in Beijing, China, September 8, 2016. (Photo by Thomas Peter/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)

Respect, Kronotsky nature reserve, Russia. The photographer’s cat, Ryska – her name means little lynx in Russian – stands outside their cabin and with aggressive posturing warns off a fox. In winter, foxes would regularly visit the cabin searching for food. If one peered in at the window, possible when the snow was deep, Ryska would sit on the other side, fur raised, and growl. When outside, she would hold her ground. The foxes were not always frightened and so encounters could be a sort of dance. (Photo by Igor Shpilenok/Unforgettable Behaviour/NHM)

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)

Double tornadoes, lightning storms and rotating supercells – this is what it's like to chase storms for a year. These dramatic images show apocalyptic weather throughout 2014 from a lightning storm to a pair of rainbows. Roger Hill, 57, has been chasing storms in the United States for thirty years and runs a tour operation with his wife Caryn. Here: a hailstorm rolls over fields, on July 22, 2014, in South Dakota. (Photo by Roger Hill/Barcroft Media)

Relatives of a missing person scuffle with police officers on the bank of the Yangtze River, near Jingjiang, Jiangsu province January 17, 2015. A search and rescue operation was still underway after the boat capsized on January 15, leaving 22 people missing, including foreigners. (Photo by Aly Song/Reuters)