Judy, a black collie whose owner was killed by a train when trying to retrieve her after she slipped her lead. (Photo by Evening Standard/Getty Images). 17th December 1976

A Siberian tiger cub is seen at the Hengdaohezi Breeding Center for Felidae on October 26, 2007 in Harbin of Heilongjiang Province, China. Established in 1986, the breeding center is one of the world's largest captive breeding base for Siberian tigers. Distributed throughout northeastern China, far eastern Russia and North Korea, over 400 Siberian tigers exist in the wild, approximately 20 in China. (Photo by China Photos/Getty Images)

A young boy adjusts his friend's Adolf Hitler mask during a game on a street in King's Cross, London. (Photo by William Vanderson/Getty Images). 1938

The knitted sculpture “William Tell” by Patricia Waller sits in the “Broken Heroes” exhibition at the Deschler Gallery on April 26, 2012 in Berlin, Germany. The exhibition of hand-crocheted comic, puppet and cartoon figures shows icons of pop culture in various unfortunate states. (Photo by Adam Berry)

Raising a flag over the Reichstag is a historic World War II photograph taken during the Battle of Berlin on 2 May 1945, by Yevgeny Khaldei.

Cropped shot of a woman flirtatiously touching leg of man in a suit with her foot under the table. (Photo by LightField Studios/Skyfish Digital Media/Getty Images)

A masked reveller poses during the Venice Carnival in Venice, Italy February 12, 2017. (Photo by Tony Gentile/Reuters)