An alligator is pictured stuck in the mud of the dry Pilcomayo river, which is facing its worst drought in almost two decades, on the border between Paraguay and Argentina, in Boqueron, July 3, 2016. (Photo by Jorge Adorno/Reuters)

Dancers wearing new bikinis perform in front of passers-by and a line of photographers during a promotional flash mob event on a square outside Shinjuku station in Tokyo on July 18, 2016. The event was organized by the Japan Swimsuit Association to promote new swimwear. (Photo by Toru Yamanaka/AFP Photo)

Two people wearing animal costumes join others as people gather to celebrate the Winter Solstice at Stonehenge in England Tuesday December 22, 2015. The winter solstice is celebrated by many people around the world as the beginning of the return of the sun. (Photo by Ben Birchall/PA Wire via AP Photo)

This picture taken on January 26, 2016 shows a monkey sitting on a bench during rehearsal at a monkey training school in a zoo in Dongying, eastern China's Shandong province. Shows featuring performing simians, popular in China and throughout Asia, are expecting a boost in the Lunar New Year of the monkey, which begins on February 8. But they are facing a growing backlash from Chinese people concerned about animal welfare. (Photo by Wang Zhao/AFP Photo)

Getting her tongue pierced was “exciting and scary” says a teen who succumbed to pressure from her best friend in Austin, Texas, February 22, 2008. This image is featured in National Geographic's exhibition “Women of Vision: National Geographic Photographers on Assignment”, on view at the Palm Beach Photographic Centre, Jan. 22 - Mar. 22, 2015. (Photo by Kitra Cahana/National Geographic)

Shortlisted: “Two big eyes” by Miao Yong (Zejiang province, China). Damselflies look over the leaves. “I was photographing insects in a park near my home when suddenly I found two damselflies in the grass. They kept flying and it was very difficult to focus until suddenly they parked behind a leaf”. (Photo by Miao Yong/2017 Royal Society of Biology Photographer of the Year)

A quake-resistant dome house decorated with Japan's popular “Kumamon” bear character is pictured at the Aso Farm Land resort in Aso, Japan on November 6, 2017. Cabins modelled after Japanese sweets and made from polystyrene foam withstood last year's deadly earthquakes in Kumamoto prefecture. (Photo by Kim Kyung-Hoon/Reuters)

Mount Etna, Europe's most active volcano, is seen from the side of a road as it spews lava during an eruption in the early hours of Thursday, March 16, 2017. Sicily's Mount Etna volcano unleashed an explosion Thursday, hurling molten rocks and steam that rained down on tourists, journalists and a scientist who scrambled to escape the barrage. Ten people were reported injured. (Photo by Salvatore Allegra/AP Photo)