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)

A New York window cleaner strapped to the side of The RCA Building in the Rockefeller Center, with St Patrick's Cathedral below him to the left. (Photo by William Lovelace/Express/Getty Images). 2nd May 1961

Space Shuttle Atlantis lands at the Kennedy Space Center July 21, 2011 in Cape Canaveral, Florida. The landing brings to a close the 30-year era of the space shuttle program that began in 1981, and has included 135 missions. (Photo by Bill Ingalls/NASA via Getty Images)