A woman dancing on the Sphinx. A pyramid can be seen in the background. (Photo by Fox Photos/Getty Images). 1928

Two men using an electric power saw to fell a tree circa 1940's. (Photo by Keystone View/FPG/Getty Images)

A German Shepard bares its teeth during Schutzhund attack dog training at Witmer-Tyson Imports February 14, 2002 in Newark, CA. (Photo by Justin Sullivan/Getty Images)

Catherine, Duchess of Cambridge speaks to soldiers as she arrives at Calgary Airport on July 7, 2011 in Calgary, Canada. (Photo by Chris Jackson/Getty Images)

Models pose backstage ahead of the Review of Australian Fashion Week show as part of Mercedes Benz Fashion Festival Sydney 2011 at Sydney Town Hall on August 24, 2011 in Sydney, Australia. (Photo by Lisa Maree Williams/Getty Images)

A model showcases designs by Twenty Seven Names in a photograph as part of New Zealand Fashion Week 2011 at a Newton Gallery on August 30, 2011 in Auckland, New Zealand. (Photo by Sandra Mu/Getty Images)

South Korean prostitutes hide their identities as they participate in a rally on September 22, 2005 in Seoul, South Korea. Prostitutes rallied against government law aimed at the s*x industry. (Photo by Chung Sung-Jun/Getty Images)

A model poses at the Le Silla Spring/Summer 2012 presentation as part Milan Womenswear Fashion Week on September 23, 2011 in Milan, Italy. (Photo by Vincenzo Lombardo/Getty Images for Le Silla)