A young visitor interacts with a baby hippopotamus swimming in its enclosure at the Berlin Zoo on January 1, 2018. Tourists and locals flocked to the zoo in the German capital on the unseasonably warm first day of the year. (Photo by Odd Andersen/AFP Photo)

A German special anti-tank gun is ready to fire during the army maneuvers in Silesia, Poland, on September 22, 1928. (Photo by AP Photo)

Filipino villagers escape to a safe area as the Mayon Volcano erupts anew in the town of Daraga, Albay province, Philippines, 23 January 2018. The Philippine Institute of Volcanology and Seismology (PHIVOLCS) agency on 22 January raised the alert level for the Mayon Volcano amid fears of a bigger eruption over the next few hours or days. (Photo by Francis R. Malasig/EPA/EFE)

Three cabaret dancers sit glum-faced in the Windmill Theatre's canteen upon hearing the news that the theatre's owners have sold out to a cinema company, on October 02, 1964. The theatre, which was the first to include nudity in its shows, has been able to cope with competition from a growing number of West End strip clubs. (Photo by Hulton-Deutsch Collection/CORBIS/Corbis via Getty Images)

Sally Rand dances on a beach in St. Petersburg, Florida, February 17, 1936. (Photo by AP Photo)

A woman made-up with the technique of Body Paint seen during the 2nd Spanish tattoo artists Convention of the Only Tattoo Barcelona in Barcelona, Spain on March 17, 2018. (Photo by Ramon Costa/SOPA Images/Rex Features/Shutterstock)

An opposition fighter from the Failaq al-Rahman brigade fires a heavy machine gun in Jobar, a rebel-held district on the eastern outskirts of the Syrian capital Damascus, on March 19, 2017. (Photo by Amer Almohibany/AFP Photo)

Germany's Kira Walkenhorst (L) taps Germany's Laura Ludwig during the women's beach volleyball qualifying match between Germany and Canada at the Beach Volley Arena in Rio de Janeiro on August 9, 2016, for the Rio 2016 Olympic Games. (Photo by Leon Neal/AFP Photo)