Dancers at the Windmill Theatre in London, England practice a routine wearing gas masks and hard-hats with their costumes, 1940. (Photo by Hulton Archive/Getty Images)

Mud-covered tourists pretend to be trapped inside a mud prison at the Daecheon Beach Mud Plaza in the city of Boryeong on South Korea's west coast, July 17, as they take part in the Boryeong Mud Festival, which opened that day and runs through July 26. Boryeong mud is rich in natural mineral component and is considered to prevent skin aging. (Photo by EPA/Yonhap)

Professor Xie Yong works on an art installation of a beaver, which is made out of plastic and around 300,000 needles, in Shenyang, Liaoning province, July 23, 2013. The needles, according to Xie, represent the pain felt by animals when their fur is taken off to produce clothing. (Photo by Reuters/Stringer)

People look at French artist Clement Briend's photographic light installation “Divine Trees”, which features images of divine figures highly revered in Asian cultures projected on trees towering over bystanders, during a media preview of the Singapore Night Festival in Singapore August 21, 2014. The Singapore Night Festival begins on Friday. (Photo by Edgar Su/Reuters)

Attnedees dressed in Zombie outfits walk down the Gaslamp Quarter outside of the 2015 Comic-Con International in San Diego, California July 8, 2015. (Photo by Sandy Huffaker/Reuters)

Blankets cover the bodies of a woman (right) and a man (left background) hit by a northbound Penn Central train (background) as they waited with a crowd at Pennsylvania Railroad station in Elizabeth, N.J. on June 8, 1968 to view the southbound train carrying the body of Sen. Robert F. Kennedy to Washington. The woman was identified as Mrs. Antoinette Severini, 54, and the man, John Curia (age unavailable), both of Elizabeth. (Photo by AP Photo)

A Russian army conscript called up for service in the Kremlin regiment and a woman say farewell at Yekaterinburg-Passazhirsky railway station in Yekaterinburg, Russia on November 15, 2018. (Photo by Donat Sorokin/TASS Russian News Agency)

An officer from the California Department of Fish and Wildlife gets ready to tranquillize a bear in Pasadena, California, U.S., August 20, 2021. (Photo by Mario Anzuoni/Reuters)