Skip to content
The Present

Masturbation: Why it’s an ‘evolutionary magic trick’

It's a mechanism we use often.

Still from Paul Weitz's 1999 film "American Pie."

In the climactic scene of Woody Allen’s clever and self-consciously juvenile film Everything You Wanted to Know About Sex* But Were Afraid to Ask, Allen’s character is a sperm cell who is waiting for his big moment. Allen’s character is not happy with his assigned fate. Nor does he get to decide when his moment will come. That is left to the operators in the “brain room,” a bustling control center that resembles a space station.

At one point, a brain operator issues a desperate order: “Have memory think of baseball players to keep sperm from premature launching.” The memory operator then begins to calmly transmit these words into a phone: “Willie Mays. Joe Namath. Mickey Mantle.”

Woody Allen’s character is afraid of being ejaculated as he fears the man might be masturbating or, to his great apprehension, “What if it’s a homosexual encounter?”

This scene, which is titled “What happens during ejaculation?” is of course a farcical take on reproductive biology, but it is also an appropriate illustration of the leading role the brain plays in the whole affair. Humans have cognitive abilities that enable us to conjure fantasies — in this case to distract the man, but more often to arouse him.

What’s the Big Idea?

Jesse Bering, the author of the 2012 book Why is the Penis Shaped Like That? describes the ability to create fantasy scenes in our heads as “an evolutionary magic trick.” He writes:

“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. When it comes to sex, we put this capacity to very good — or at least frequent — use.”

This “advanced social cognitive system” makes us unique among animals, in that we masturbate to completion. And yet, why would humans evolve to waste sperm in such a gratuitous fashion? Bering points to the theory that men are “making room for better quality sperm cells, fresher sperm cells, and getting rid of the old.”

The brain’s ability to produce pornographic movies can also be used as a tool in monogamous relationships. As Bering tells Big Think, we don’t really like to admit it to sexual partners but we introduce “a whole roster of other players in our heads as we’re having sex with that person.” So is that cheating? Bering sees the brain as a pornographer that can help married couples when the “romantic erotic fatigue inevitably occurs.”

Watch the video here:

What’s the Significance?

“I really don’t think there’s anything too outrageous in terms of what you can concoct in your head,” Bering says, “for the purposes of masturbation at least.” But what about actual pornography–by that I mean the kind of videos that are being created every 39 minutes in the U.S. and are being watched by 28,258 Internet users every second? Is it killing our sexual fantasy lives? After all, it’s not just the volume, it’s the content itself. Bering points out in his book that we can easily access “an online smorgasbord of real people doing things our grandparents couldn’t have dreamed up even in their wettest of dreams…”

Davy Rothbart took up this question in great detail in New York Magazine examining how the “tsunami of porn is affecting the libido of the American male or, more selfishly, mine.” In a broader sense, Rothbart asks how pornography is affecting men and women on a “fundamental neurological level”

Bering speculates that in addition to potentially diluting our creative potential when it comes to our sexual fantasies, pornography might have consequences for other aspects of our lives. Is porn affecting productivity at work or the ability to solve problems creatively? Bering points out that these are the types of questions that scientists haven’t really asked yet with respect to pornography.

What’s Next from Jesse Bering? An Invitation to Impropriety on Big Think

In his book’s opening chapter, entitled “An Invitation to Impropriety,” Bering offers full disclosure: “my perspective is that of a godless, gay, psychological scientist with a penchant for far-flung evolutionary theories.” Bering, who Paul Bloom has called “the Hunter S. Thompson of science writing,” says he was born with a salacious mind and has come to train his fearless curiosity on a world “in which nothing [is] sacred, no question too absurd or off-limits…”

To give you an idea of the range of subjects he covers, when I took Why is the Penis Shaped Like That? to the beach I was asked by a friend what I was reading about. “Oh, not much,” I replied. “Just a little bestiality, cannibalism and some sexsomnia.”

Smarter faster: the Big Think newsletter
Subscribe for counterintuitive, surprising, and impactful stories delivered to your inbox every Thursday

These subjects, as Bering admits, are by their very definition sensational, but they can also teach us the most about ourselves. Bering writes:

“Often the most titillating topics are uniquely able to raise deeper philosophical questions and to bring much more substantial issues to the surface. For instance, in reading about zoophiles, you may find yourself, as I did, questioning your own knee-jerk moralistic sexual repulsions; a look at the evolution of pubic hair or acne unexpectedly reveals our close genetic relationship with other apes; masturbation fantasies reveal what makes us unique in the animal kingdom; and foot fetishists expose how our adult turn-ons are permanently calibrated by often-innocent childhood experiences.”

In this post, we examined masturbation fantasies, perhaps the tamest of subjects that Bering deals with. In introducing Bering, we wanted to go gentle. Stay tuned for more.

Follow Daniel Honan on Twitter @Daniel Honan


Up Next