Scientific American: frequent masturbation makes human species special and unique

Jesse Bering at Scientific American looks at one quality that makes the human species “special and unique”: masturbation.

This conjuring ability to create fantasy scenes in our heads that literally bring us to orgasm when conveniently paired with our dexterous appendages is an evolutionary magic trick that I suspect is uniquely human. It requires a cognitive capacity called mental representation (an internal “re-presentation” of a previously experienced image or some other sensory input) that many evolutionary theorists believe is a relatively recent hominid innovation.

He cites a research study by evolutionary biologists which argued that frequent masturbation makes evolutionary sense:

because there is a “shelf-life” for sperm cells – they remain viable for only 5-7 days after production – and because adult human males manufacture a whopping 3 million sperm per day, masturbation is an evolved strategy for shedding old sperm while making room for new, fitter sperm.

Makes sense to me.