Three secondary schoolboys smoking an illicit cigarette in Hyde Park, London. (Photo by Evening Standard/Getty Images). May 1972

Smoke billows from Jinnah International Airport in Karachi, Pakistan, June 9, 2014. (Photo by Athar Hussain/Reuters)

Young man making the O.K. sign. (Photo by George Marks/Retrofile/Getty Images). Circa 1950s

Women playing in the street as the snow falls on Johannesburg for the first time in seventeen years. (Photo by Keystone/Getty Images). 1st September 1962

Indonesian mahouts clean their Sumatran elephant in a river near the zoo in Medan, North Sumatra, Indonesia, 12 December 2014. According media reports, the smallest of the Asian elephants, Sumatran elephant (Elephas maximus sumatrensis) is facing serious pressures arising from illegal logging and associated habitat loss and fragmentation in Indonesia. The population has come under increasing threat from rapid forest conversion to plantations. (Photo by Dedi Sahputra/EPA)

A model walks the runway during the John Galliano Ready to Wear Autumn/Winter 2011/2012 show during Paris Fashion Week on March 6, 2011 in Paris, France. (Photo by Pascal Le Segretain/Getty Images). PARIS, FRANCE – MARCH 06

Model Irina Shayk and Arthur Sales present the new collection “Xti 2011-12” on March 14, 2011 in Madrid, Spain. (Photo by Carlos Alvarez/Getty Images)

A Chinese snake charmer performs at a temple fair to mark Chinese New Year February 19, 2007 in Beijing, China. Chinese worldwide are celebrating the Chinese Lunar New Year of the Pig. (Photo by Guang Niu/Getty Images)