An army dog stands up as retiring soldiers salute their guard post before retirement in Suqian, Jiangsu province, China on November 29, 2017. (Photo by Reuters/China Stringer Network)

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)

Revellers gather for the start of the Annual SantaCon Bar Crawl at Father Duffy Square, a section of Times Square, on December 14, 2019, in New York City. SantCon is an event where people make donations to charitable causes and dress up as a Christmas character and visit bars around the city. (Photo by Steven Ferdman/Getty Images)