People purchase the book “Steve Jobs” by Walter Isaacson on launch day at Shanghai's City of Books on October 24, 2011 in Shanghai, China. The book was launched in 30 book cities at the same time across the country. (Photo by ChinaFotoPress/Getty Images)

A concept illustration of the world's first forest in the sky, the Bosco Verticale green twin towers currently under construction in Milan, Italy. Towering over the city skyline the world's first forest in the sky will be a sight to behold. With tree equal to one hectare of forest spanning 27 floors these 365 and 260 foot emerald twin towers will be home to an astonishing 730 trees, 5,000 shrubs and 11,000 ground cover plants. (Photo by Boeri Studio)

Sumatran tiger Jumilah is seen with one of her cubs on display at Taronga Zoo on October 25, 2011 in Sydney, Australia. The Sumatran tiger cubs, born in August to mother Jumilah, will meet the public for the first time this week. (Photo by Mark Kolbe/Getty Images)

Glamour model and actress Sabrina seated on the knee of Arthur Askey. (Photo by Keystone/Getty Images). 1955

A model showcases designs on the catwalk during the NE(degrees)¤TIGER Couture 2012 on the second day of China Fashion Week Spring/Summer 2012 on October 25, 2011 in Beijing, China. (Photo by Feng Li/Getty Images)

A recruitment drive during the First World War at Trafalgar Square, London. (Photo by Central Press/Getty Images)

A Baby Flying Fox (Pteropus) hangs from a clothes line at a temporary bat rehabilitation centre on December 3, 2008 on the Gold Coast, Australia. (Photo by David Hardenberg/Getty Images)

Women in Chicago being arrested for wearing one piece bathing suits, without the required leg coverings. (Photo by Topical Press Agency/Getty Images). 1922