In this March 18, 2015 photo, a boy rides a mechanical bull for children at the Texcoco Fair on the outskirts of Mexico City. In Mexico, these types of fairs date back to Spanish colonial times, and in some smaller communities they are organized around the feast days of Roman Catholic saints. (Photo by Eduardo Verdugo/AP Photo)

A woman dressed as a Viking drinks local red wine during the annual Viking festival of Catoira in north-western Spain August 2, 2015. The festival re-enacts past Viking raids in the area and is celebrated annually on the first Sunday in August. (Photo by Miguel Vidal/Reuters)

The setting sun illuminates the sky behind wind turbines of a wind park near Neusiedl am See, December 22, 2014. (Photo by Heinz-Peter Bader/Reuters)

Japan's delegation gather to sign the formal surrender document on the U.S. Navy battleship USS Missouri in Tokyo Bay in a September 2, 1945 file photo. (Photo by Reuters/US Navy)

“A Little Monkey on the Cliff”. “A cold front hit the Nagano prefecture. I saw a little monkey enduring the cold in Jigokudani Monkey Park. This little monkey is really cute”. (Photo by Hidetoshi Ogata/Smithsonian Photo Contest)

A female brown bear with cubs fishing on Lake Kronotskoye as part of the South Kamchatka, Russia on Sanctuary, August 13, 2017. (Photo by TASS/Barcroft Images)

In a new project, an international group of photographers have joined forces to use their powerful images to raise awareness and funds to help stop the illegal wildlife trade. Here: Fennec foxes are captured for the illegal pet trade. This three-month-old pup was for sale in a market in southern Tunisia. (Photo by Bruno D'Amicis/Photographers Against Wildlife Crime/Wildscreen/The Guardian)

The northern lights, or aurora borealis, illuminate the sky over Flakstad beach on Lofoten Islands in the Arctic Circle on September 5, 2017. (Photo by Jonathan Nackstrand/AFP Photo)