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Men Behaving Badly: A Lesson from Duck Sex?

I hate the phrase “humans and animals” or derisively calling someone an animal. We’re not plants, fungi, bacteria, or protozoa, nor are we above other members of the animal kingdom, at least evolutionarily speaking. In recent weeks, with eclectic examples of prominent human males behaving badly dominating the news, I think of the wider biological lens.

Were the media moguls who forced parts of their anatomy into their female employees, the beloved TV star drugging and assaulting dozens of women, and the privileged schoolboys allegedly groping girls at long-ago parties just acting as biology dictates? Does the rush of power and/or the confusion of an alcoholic haze prevent some XYs from temporarily accessing the regions of their brains that might allow thinking to overcome the testosterone rush and halt their aggression, while dampening the hippocampus so that they later can convincingly claim to have no recall?

I don’t think so.

A Few Minutes of Violence Can Echo Over a Lifetime

The short time that it may take to assault a woman – for a drunk adolescent to hold a classmate down and tear at her clothing as his friends laugh, or for a TV executive to expose himself and roughly push down his victim’s head – can reverberate for ever after for the victim, whether or not she has the presence of mind and opportunity to safely collect “evidence.”

“More than one in every four women in the world experience sexual violence in their lifetime, most often as teenagers and young adults. These traumatic experiences leave memories in the brain, which are difficult if not impossible to forget,” begins an article just published in Frontiers in Psychiatry, from Emma M. Millon, Han Yan M. Chang and Tracey J. Shors from the Center for Collaborative Neuroscience at Rutgers University.

Their study tracked 183 women aged 18-39, 64 of whom were victims of sexual violence. The 64 women reported strong, detailed memories, reliving the event clearly rather than it fading with time, as it might have for the drunken students, film producer, or TV celebrities of recent headlines. “Each time you reflect on an old memory, you make a new one in your brain because it is retrieved in the present space and time. What this study shows is that this process can make it even more difficult to forget what happened,” said Shors. The team has developed a program to help women pay less attention to the shattering and persistent memories.

Today, September 27, we’ll hear Judge Brett Kavanaugh and Professor Christine Blasey Ford’s testimony about their alleged interaction years ago, as girls and women are making their voices heard around the country, once again, even as plans solidify to nominate the judge ASAP, a maddening dismissal of #MeToo. I can’t make it to Washington, so I thought I’d look at similar behavior among males of other species.

“Forced Mating”

After mating a female praying mantis consumes the male.

Sexual violence against females does seem to be rooted in biology. Rape in non-human animals: An evolutionary perspective” discusses “forced mating in orangutans, mallard ducks, and scorpionflies.” That diversity of primates, birds, and insects suggests an ancient biological legacy, perhaps shared DNA affecting behavior. Another paper from the ethology literature describes how female scorpions eat their mates after sex, as do praying mantises and spiders.

Laboratory simulations confirm field observations. A study in rats from 1942 is telling: “Analysis of the stimuli adequate to elicit mating behavior in the sexually inexperienced rat,” in the Journal of Comparative Psychology.

“Sexually inexperienced male rats” were rendered unable to see, smell, and touch with their snouts and lips, the deficits introduced “either singly or in combination.” Then the males were teased by “incentive animals” including a “sexually receptive female, a female in heat but immobilized by an anesthetic, a castrated female, a small young male, a female guinea pig, and a female rabbit.”

Although the male rats didn’t need all 3 senses bombarding their snouts to seek sex, having only two dampened their “excitability” a bit, and relying on only one stimulatory sense stopped mating behavior – but only if the rats were sexually inexperienced. However, “if the rat possesses a low copulatory threshold, he will mate despite reduced excitation” and “sexually experienced males continue to copulate” with only one such sense.

Extrapolating widely, then, a high school lad might need to touch and see or smell his victim to carry on; an experienced male of the species, like a Harvey Weinstein, Matt Lauer, or Les Moonves, would presumably need less enticement. The rat study of course could not factor in the effects of feeling powerful and in control.

A Warning from Ducks

We know a lot about the mating rituals of certain duck species, those that have penises, thanks largely to Yale ornithologist Richard O. Prum and media coverage of his 2017 book “The Evolution of Beauty: How Darwin’s Forgotten Theory of Mate Choice Shapes the Animal World – and Us.”

Certain duck species have extremely long penises that unfurl when the mating season commences, the organ an elaborate spiral festooned with interesting textures, like an old-fashioned French tickler. “The 1-pound, foot-long Argentinian lake duck has the longest of all with a member that is 4 inches longer than its body,” wrote Susannah Cahalan in the NY Post (author of the excellent Brain on Fire.)

In species in which male ducks greatly outnumber females, come mating season, the drakes may become frenzied enough to force themselves on the hens. But evolution has helped some females temper the violence – their reproductive tracts are booby-trapped with spiky sharp twists and turns that can counter the “forced copulations” from what Dr. Prum dubs the “explosive corkscrew erections” of male ducks.

Enter natural selection. A violent male can’t push his organ into the female without yelping pain; a gentler one can. And so the genes from the gentler ducks persist. It’s an elegant example of “survival of the fittest” – the Darwinian phrase that doesn’t mean physical prowess, but the ability to leave fertile offspring and continue the perpetuation of one’s genes. The adaptation to counter sexual violence perhaps contributed to the penislessness of many duck species. Instead the males of organless species entice females with a “cloacal kiss,” a rubbing of the nether regions that seals sperm and egg.

“For me a simple comparison of human male coercion and animal coercion is not really valid because the science indicates that human male sexual violence is a cultural phenomenon, not a biological adaptation,” Dr. Prum told me.

So he, too, separates humans from other animals. But that’s ok. We agree that the sex-obsessed celebrities and slobbering adolescents are choosing their bad behavior – not simply responding to hormones or alcohol. Forcing mating behavior – aka sexual assault – is never okay.


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