Tourists use a selfie stick on the Trocadero Square, with the Eiffel Tower in background, in Paris, Tuesday, January 6, 2015. Selfie sticks have become popular among tourists because you don't have to ask strangers to take your picture, and you can capture a wide view in a selfie without showing your arm. But some people find selfie sticks obnoxious, arguing that they detract from the travel experience. (Photo by Remy de la Mauviniere/AP Photo)

A woman plays around as she walks across a glass-bottomed suspension bridge in a scenic zone in Pingjiang county in southern China's Hunan province Thursday, September 24, 2015. The bridge, 300 meters (984 feet) long and 180 meters (590 feet), opened to visitors on Thursday for the first time since its conversion from a regular suspension bridge was completed. (Photo by Chinatopix Via AP Photo)

Contestants of a tourism beauty pageant balance eggs on their collarbones as they cruise along the Yellow River in Jiyuan, Henan province, China, June 22, 2015. The contestants believe that if they are slim enough, their collarbones will allow them to balance the eggs securely on their bodies. (Photo by Reuters/Stringer)

Naked activists for animal rights, covered in fake blood, perform during a protest against the use of fur and leather, at Catalunya Square in Barcelona, Spain, December 16, 2018. (Photo by Albert Gea/Reuters)

A girl types on a computer as she demonstrates the interior of the new Volvo S90 during the Auto China 2016 auto show in Beijing April 25, 2016. (Photo by Damir Sagolj/Reuters)

Each year Nikon Small World recognizes the excellence of photography taken under the microscope. The contest showcases the beauty and complexity of life. Anyone interested in microscopy and photography can enter the contest and in its 42nd year, Nikon Small World received 2,000 entries from 70 countries. Here: 11th Place; Scales of a butterfly wing underside (Vanessa atalanta). (Photo by Francis Sneyers/Nikon's Small World 2016)

This handout photo taken on February 12, 2017 and released on February 16 by the International Federation of Red Cross and Red Crescent Societies (IFRC) shows Mongolian herder Munkhbat Bazarragchaa (C) dragging two sheep – which recently died due to the weather - to a pile of dead animals behind his “ger” in Khuvsgul province, northern Mongolia. Thousands of Mongolian herders face disastrous livestock losses from dreaded severe weather known as the “dzud”, the Red Cross said on February 16, 2017 in launching an international emergency aid appeal. (Photo by Mirva Helenius/AFP Photo/IFRC)

This strange coral-looking specimen is actually a mushroom. The photo, “Beautiful Destroyer”, was taken in the Panamanian tropical rainforest where the mushroom produces nitrogen, an element vital to soil health. (Photo by Sarah A. Batterman)