Is it shocking for an adult male to be sexually attracted to a person under 18 years of age? Many in the U.S. today answer “Yes, absolutely.” Probably some who would answer that way have a different view privately, or at least are conflicted. Or, especially if they are male, would recognize the possibility of such feelings in themselves. But there’s almost no space in public discourse for admitting that, no space for anything other than absolute condemnation. For family and friends of someone incarcerated for an offense involving such attraction, this silence doesn’t make dealing with the situation any easier.

Making sex involving minors almost unthinkable might be seen as a way of discouraging it. But it’s clear that people don’t wait until their 18th birthday to become sexual. Nearly 40% of U.S. youngsters have sexted before reaching age 13, according to one study – in other words, broke child pornography laws, that nowadays can lead to long prison sentences and permanent forfeiture of civil rights. And plenty of sexual relationships among minors themselves involve age gaps. Even people who concerned about the potential harm of such sex involving persons under 18 recoil at the over-punishments and demonization meted out to offenders – such as the mandatory 10-year sentence handed down in 2005 to a 17-year-old Georgia youth for consensual oral sex with a 15-year-old girl. So it’s a useful effort – not just for those of us connected to a person facing punishment – to peel back some of the layers of unthinkability about attraction to minors.

A taboo around talking about erotic feelings for minors makes it easy to miss how common such feelings are, based on well established research that’s been replicated time and again and approached from different angles. A small degree of sexual response even to young children is common in men.

“Pedophilia” as used by psychiatrists has a distinct and delimited meaning – primary and persistent attraction to prepubescent girls or boys – generally age 10 or younger. Psychiatry considers pedophilia in this sense – not incidental attraction – as a mental disorder (though some experts disagree and consider it simply a variant).

Currently, American psychiatry considers attraction to pubescent young persons (generally, ages 11 to 14) “hebephilia”. Attraction to those around 15 to 18 is defined as “ephebophilia.” Neither hebephilia nor ephebophilia is considered a disorder – such feelings are so common that it would be like calling curly hair a disease.

Some psychiatrists mounted an effort starting in 2008 to get hebephilia (attraction to pubescents) defined as a mental disorder. The attempt failed in 2013, when the board of the American Psychiatric Association rejected the idea. One leading psychiatrist, Dr. Richard Green (Cambridge University, UCLA) summed up the case in a letter to a psychology journal: “Sexual preference for 14-year-olds as a mental disorder: you can’t be serious!!”

There are different ways to measure male attraction. None are perfect, but they offer clues.

One way is to just ask men what kinds of people they’re attracted to. Of course, the answers may not always be truthful. In a 2014 Canadian survey of male college students, 99.1% reported they were not even slightly sexually attracted to pubescents ages 12 to 14.

Given other evidence, that result seems to reflect the opprobrium heaped on such erotic desire today more than their actual feelings.

A 2011 study found that 52% of male students reported at least some sexual arousal to at least 1 of 3 stories involving sexual activity with a child.

In a study from 1980 cataloging various erotic fantasies, 94 adult men were asked if they experienced various fantasies during intercourse or while masturbating. Sixty-six percent of respondents experienced the fantasy “scene where you initiate a young girl,” and it was the 12th most common fantasy scenario out of 46.

Another way to gauge male attraction is to attach a rubber ring that measures an erection in response to different stimuli (pictures, stories). It’s called “phallometry.” If the sample of men tested is representative of men generally, the results of this sort of phallometry could be expected to be more or less valid. It’s a method that potentially bypasses men’s understandable resistance in today’s climate to admit to forbidden desires.

A meta-analysis of seven phallometric studies found that 21.6% of men recruited from the community are more or equally sexually aroused by youngsters up to 13 years of age as by adults. Another researcher summing up the evidence similarly concluded, “Approximately 20% of normal men are determined to be pedophiles based on data from control groups and other non-clinical / non-forensic males.”

British academic Sarah Goode summed up the results of multiple phallometric studies of men recruited from the community or among college students, showing that anywhere from 17% to 58% were capable of sexual arousal in response to prepubescent children of one or the other sex.

These numbers are already high, but in the loose, catch-all way pedophilia is used in popular discourse, the term actually covers the vast majority of males – and represents peaks rather than tails of men’s and boys’ desires. Men in trouble for sexual feelings or acts involving persons in their late teens – 16 or 17 – are routinely called “pedophiles,” even while young people of that age are in most places in the West even today considered capable of giving consent to sex. Former Subway restaurant spokesman Jared Fogle was condemned as a “pedophile” in the media. He had been twice married to women and has two children. At the start of his nearly 16-year sentence in 2015, he was beaten up in prison by an inmate who reportedly “hates child molesters.” But the one charge involving actual sexual contact with a minor for which Fogle was convicted involved non-coerced sex with a 17-year-old woman. It illustrates how “pedophile” has become an epithet thrown with the precision of mud balls, like how “fag” is yelled out in schoolyards. Google returns nearly 200,000 results for “‘Harvey Weinstein’ pedophile,” despite the jailed movie mogul having only been accused of sexual encounters with unwilling fully adult women.

Even with “pedophile” being used wholesale to call out alleged male sexual misbehavior, it remains that the further a man’s interests dips below the age of 18, the greater the condemnation. This is so even though the “age of consent” varies dramatically in the U.S., if it exists at all, for other major decisions young people face, such as joining the military (possible at 17), buying alcohol (21), getting a permit to drive a car (14 in some nine states), or undergoing sex-change therapy (seen by advocates as best begun before puberty, around 12). Some 13 states have no minimum age for youngsters to be prosecuted as adults and incarcerated in adult jails.

But 18 has become a pretty hard line in the U.S. with regard to sex. So is sexual attraction to 16- and 17 year olds completely normal and expectable in males?

Official Western psychiatry, as we’ve seen, consider such attraction normal. So has the law, until recently, and in some small ways sometimes, even now.

A study of a popular free online dating site showed that women of 18 got the most attention from men … with responses falling for every older age … but of course, no younger age was tested. Would an age younger than 18 have been more popular? Pornography showing actors 16 and 17 years of age was not criminalized in the U.S. until 1984. That was the year Traci Lords, then 16 years old, used a fake ID to appear as a model in Penthouse magazine and commercial porn films. One of the films she starred in that year was not just popular – it won the porn industry’s “best movie” prize, porn’s equivalent of the Oscars, and she became one of the highest paid porn performers of her day.

In a 2012 book A Billion Wicked Thoughts: What the Internet Tells Us about Sexual Relationships Boston University researchers looked at a trove of leaked sex-related internet search terms – overwhelmingly males looking for visual imagery. Searchers had all kinds of quarry: photos of women endowed with big breasts or showing off gorgeous thighs … but one search term was more popular than any other: naked girl 16.

These examples suggest that men’s and boys’ attraction to young women of 16 and 17 is not a marginal attraction, but at or near the peak of the bell curve of male erotic response.

What about men’s attractions to those under 16? For centuries throughout the Western world, until the late 19th century, the minimum age of marriage for girls hovered between 10 and 12, usually with a somewhat older male (who had time to establish himself in work enough to support a family).

In the past, male homosexuality often involved an age differential, involving adolescents who had high sex drive but no socially acceptable heterosexual outlet and men who were attracted to them. This older-younger pattern remains evident in the West even to today, in all-male contexts such as prisons and boarding schools, where it arises spontaneously, among inmates who outside of institutional walls would act heterosexually. Most famous historical figures now celebrated as “gay” were in fact mainly erotically oriented toward youths, such as artist and polymath Leonardo da Vinci, poet Walt Whitman, writer and wit Oscar Wilde, or computer-science pioneer Alan Turing. But in societies where these relationships were at least tolerated, it’s striking that a large proportion of men seem capable of feeling such attraction. In Renaissance Florence, upwards of 2/3rds of men were implicated in these kinds of age-structured relationships according to court records. In ancient Greece, these kinds of bonds were celebrated as ideal contexts for mentorship.

This older-younger pattern is dominant in the West, even to today, in all-male contexts such as prisons and boarding schools, where it arises spontaneously, among inmates who outside of institutional walls would act heterosexually.

In the West today, where man-boy bonding today is strongly discouraged for fear of sexual abuse, only those males with a strong predisposition manifest such feelings. They are especially likely in today’s hostile environment to get in trouble.

Seeing how ordinary erotic feelings for minors are among males, how they are almost certainly what males are evolved to feel, does not speak to whether sex involving minors is legal or right for today. Ours is a world where girls’ education is vitally important (instead of child-bearing early and often), where human overpopulation threatens the world’s ecology, and in which girls join boys going to school rather than cultivating mentors. But this backdrop of evidence suggests we’ve overshot in demonizing men and boys who, from a Big Picture perspective, show completely ordinary impulses. Impulses, based on just what we know about internet search terms and youth sexting, put, if not Everyman and Everyboy, at least a large proportion of men and boys today at risk of years of imprisonment. Between 10 and 20% of state prisoners in the U.S. are inside for sex offenses – in some states as high as 30%, notes University of Pennsylvania’s Marie Gottschalk. And federal incarcerations for porn possession rose more than 60-fold from 1996 to 2010. Around one million are deprived of virtually all civil rights as registrants. Those of us with family or friends caught up in this system can legitimately ask why has America chosen to sacrifice so many of its sons. As a disastrous War on Drugs finally seems to be letting up, surely there are ways to foster sexual behavior in line with today’s mores without destroying hundreds of thousands of lives.