Yin and yang. Sеxy women grey background. Sensual women in erotic lingerie. (Photo by Alamy Stock Photo)

Riot police fire tear gas at demonstrators during a protest against fare hikes for city buses in Sao Paulo, Brazil, January 8, 2016. Brazilian riot police on Friday fired tear gas and stun grenades to disperse a violent protest against a rise in public transport fares in the country's largest city, Sao Paulo. (Photo by Nacho Doce/Reuters)

Germany, Business couple making love under desk. (Photo by Roman Maerzinger/Getty Images)

Esau the ape at the piano. (Photo by Reinhold Thiele/Topical Press Agency/Getty Images). Circa 1900

From the waters edge a New York policeman urges two young children to put their bathing costumes back on. (Photo by Ed Clarity/Keystone/Getty Images). July 1949

A horse-drawn cart passing through a section cut out of the base of a giant sequoia tree in the Mariposa groves of Yosemite Park, California. (Photo by Carleton E Watkins/Getty Images). 1870

Amy Winehouse's father Mitch Winehouse (C) mother Janis Winehouse (L in white) brother Alex Winehouse (R) and former boyfriend Reg Traviss (2nd R) look at floral tributes left at her house by fans on July 25, 2011 in London, England. (Photo by Gareth Cattermole/Getty Images)

Japanese chorus girls appear to be drilling in military tactics atop their theater building as they perform salutes, June 30, 1937. The officer is from the Japanese regular army and says the girls display more rhythm in their drills than do the regular troops. (Photo by AP Photo)