Dancers wearing traditional attires take part in the 7th Annual Ingoma Dance Competition organised by The Natal Playhouse theatre in Durban on March 21, 2017. The Ingoma Dance is considered one of the most purist forms of traditional Zulu dance. (Photo by Rajesh Jantilal/AFP Photo)

A dog, at the behest of his owner, rides a skatebaord on April 3, 2017 in Berlin, Germany. The dog's owner, who looked like he might be homeless, coaxed the dog to ride the skatebaord and asked passersby who stopped to watch for money. (Photo by Sean Gallup/Getty Images)

The model Gigi Hadid receives attention in Soho, New York, USA on June 27, 2017. (Photo by Broadimage/Rex Features/Shutterstock)

United States' Inika McPherson prepares an attempt during the women' s high jump final during the World Athletics Championships in London Saturday, August 12, 2017. (Photo by Kai Pfaffenbach/Reuters)

A walrus kisses a visitor during a sea animal show at the Hakkeijima Sea Paradise aquarium-amusement park complex in Yokohama, southwest of Tokyo, Monday, September 11, 2017. (Photo by Shizuo Kambayashi/AP Photo)

Members of the Women's Organization to War on Styles (WOW) picket a dress shop in Berkeley, Calif., August 23, 1947, in protest to longer skirts and padded hips. They are the wives of GI students at the University of California. Left to right: Jackie Houser; Wanda Ames; Dorothy Inman; Terry Ligon; Ruth Van Arkel; Carrol Reynolds, and Barbara Carmichael. (Photo by AP Photo)

Cave Diver, Anhumas Abyss, Bonito, Brazil: The Anhumas Abyss is an underground cavern with a crystal-clear lake below, more than 260 feet (79 m) deep. A visitor must enter through a narrow opening at the top of the chamber and rappel into the cave. Snorkeling and scuba diving in the lake reveal amazing scenery. Distinctive, conical limestone stalagmites and stalactites occupy the lake and the surrounding area, some reaching 65 feet (20 m) high. (Photo by Marcio Cabral/Nature’s Best Photography Awards 2017)

Palestinian man Mohammed al-Hoor, 23, demonstrates his street workout skills in Nuseirat refugee camp, in the central Gaza Strip on May 2, 2017. (Photo by Mohammed Salem/Reuters)