Two guards perform an execution in China, one holding the gun, the other holding a mask over the victim's face. (Photo by General Photographic Agency/Getty Images). Circa 1925

A Tibetan woman displays her Qing Dynasty family dress in Zhailong Village on April 24, 2005 in Danba County of Ganzi Tibetan Autonomous Prefecture, Sichuan Province, China. (Photo by China Photos/Getty Images)

A 70-metre-long Noah's Ark replica constructed of steel and American cedar on March 31, 2005 in Schagen, Netherlands. (Photo by Michel Porro/Getty Images)

Three prostitutes lean out of a window in Santiago, Chile, in an attempt to entice customers inside, circa 1950. (Photo by Three Lions/Getty Images)

Florence the baby zebra foal, runs in its enclosure at Edinburgh zoo September 4, 2008 in Edinburgh, Scotland. This arrival at the zoo is particularly important as the Grevy's zebra is listed as endangered, with only an estimated 1,500 to 2,000 remaining in the wild. (Photo by Jeff J Mitchell/Getty Images)

Musician Simon Desorgher walks his giant sphere on the foreshore of the River Thames after a rehearsal for a performance of “Water Cycle for flute and sound system” on the river on September 11, 2009 in London, England. (Photo by Peter Macdiarmid/Getty Images)

French tennis champion Suzanne Lenglen (1899–1938) high-kicking during a doubles match at the Wimbledon Lawn Tennis Championships. (Photo by Kirby/Topical Press/Getty Images). 1924

Film actress Audrey Hepburn (1929–1993) on a film set with her pet poodle, circa 1960. (Photo by Hulton Archive/Getty Images)