The Tango, a now popular dance between a man and a woman, started in it's current form in the mid 1800s, after a massive migration to Argentina, mostly by men. Because men outnumbered women by quite some number, the only way for a man to get close to a woman was via a brothel or by dance. The men practiced together, as you'd have to be a great dancer to get a woman's attention. So, this very sexual dance you see now, was born out of the reality for men in those old days. Nowadays, you see it performed often, usually on the street corners of Buenos Aires, with live musicians or a pre recorded soundtrack, and they do it for the tips ! These are all shot from those streets in BA.