“It is certain that with almost all animals there is a struggle between the males for the possession of the female. This fact is so notorious that it would be superfluous to give instances.”
–Darwin, Sexual Selection and the Descent of Man, 1871
There are parasites, and there are hosts.
Human sperm are cheap. Made up of the most densely packed eukaryotic DNA known to man, propelled by a tail roughly 50 µm long, men make millions of them. As needed. Over and over again.
Human eggs are precious. Roughly 100 µm in diameter, or around 10,000 times the volume of sperm, women are born with half a million of them. Every ovum is covered with a corona radiata—two or three layers of protein-supplying cells, and a zona pellucida—the hard outer coat that sperm have to get through; they’re filled with cortical granules—enzyme-carriers that keep all but one sperm out, and with organelles like mitochondria—that power the cell. A few hundred are released, and they’re never replenished.
The upshots are not always pleasant. As Darwin himself pointed out in his 1871 book, and as more than a few foragers and farmers have been aware for thousands of years, most males compete for female access. Across species, males court, cajole, herd, and occasionally harm females they hope to get close to.
Human males do too. The psychologist David Buss, with help from his many prolific students, and his many prolific colleagues, has spent the better part of a lifetime documenting la différence. They’ve looked at differences in male and female appetites for sex, and at some of the consequents: at differences in sexual jealousy, mate guarding, stalking, and rape.
They’ve found that most men want sex with a number of partners. In a massive study of 16,288 subjects, across 52 countries on six continents and 13 islands, men admitted they wanted sex with 1.87 partners over the next month; women wanted just 0.78. Looking farther ahead, over the next 10 years, men said they wanted at least six partners; women wanted two. The difference between men and women was universal.
Other researchers have found that sexual coercion is common and that the perpetrators are usually men. In a study of 10,000 recent sexual harassment complaints across the U.S., 83% were filed by women, but just 16.5% by men. All of 63% of women said they’d be insulted if a co-worker of the opposite sex propositioned them; 67% of men would be flattered.
Other studies have shown, repeatedly, that sexual jealousy is stronger in men than in women. In societies from Bolivia to Brazil to Chile to China to Ecuador to England to Fiji to Indonesia to Ireland to Korea to Namibia to Nicaragua to Norway to Romania to Spain to Sweden to Tanzania, men are more upset by a) imagining their partner having sex with somebody else, than by b) imagining their partner falling in love with somebody else. For women, the trend is the reverse. And again, the difference is universal.
Probably at least partly as a result, stalking is something that men sometimes do, and that women generally do not. Young women are often stalked. A study of 18,013 Kentucky high school girls found that 19% reported having been victims of stalking within the past 12 months. Stalking victims can be physically harassed. In another study of 220 college women, 62% of stalkers threatened physical violence, and 36% of victims experienced it. Worst, stalking can be deadly. Another group of researchers found that 76% of women who were killed by their exes were stalked by them first.
You always hurt the one you love.
Except when you don’t.
My first memories of my father are from the emergency room, where he’d take me when I had an asthma attack. I remember his concern when I got sick, and his sense of humor as we drove back home.
In my first memories of my daughter, she’s in her father’s arms. I knew that no matter what happened to me, she’d be fine.
My son-in-law is a fabulous father. And my son, who was married in April, will be.
Dads matter. More than any other mammal, more than any other animal, human males can make enormous investments in their young. Many feed, carry, comfort, and provide for their infants and children, adolescents and adult daughters and sons.
Evolutionary psychologists study sexual predators’ strategies for good reasons. Not to recommend them. But to recommend how to end them.
Buss, David M. 2021. When Men Behave Badly. New York: Little, Brown Spark.