The 'Cats that Look like Pin-Up Girls' Tumblr features a variety of similarly posed felines. Once the pinnacle of female sexuality, pin-up girls have changed and evolved throughout the years to become the modern day Playboy Bunnies and Sports Illustrated models they are now recognized as.

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)

Photographer and artist Jill Greenberg poses at her home to promote her Exhibit “Glass Ceiling: American Girl Doll” And Billboard For LA on September 29, 2011 in Los Angeles, California. (Photo by Frazer Harrison/Getty Images)

In 1949, LIFE magazine sent famed photographer Nina Leen to document the daily life of a sassy troupe of young women who had run off and joined the famous Barnum & Bailey Circus in Sarasota, Fla. What developed was a portrait of a sisterhood formed over acrobatics that mixed high-flying wire acts with fashionable high-waisted shorts. Sarasota was once considered “the home of the American circus”. Here: an aerialist smoking while rehearsing for the Ringling Bros. and Barnum & Bailey Circus in Sarasota, FL in 1949. (Photo By Nina Leen/Time Life Pictures/Getty Images)