sam Says: "You could just as easily (or more easily) say that monkeys relax their partner or get them in the mood by grooming them."

- If you consider it to be merely foreplay, why would less foreplay be necessary in the presence of competition? - "If there were several females in the area, the cost of buying sex would drop dramatically..."

Are they closet homosexuals turned on by the presence of other females? I suppose you could test that hypothesis by testing for physiological markers indicating stimulation. Frankly, I find their explanation more plausible though.

Great article.