Here's an interesting piece from The Atlantic from July 17. "Could the Penn State Abuse Scandal Happen Anyplace Else? Definitely." It's an interview with Chris Gavagan who was involved in making a documentary of sexual abuse in sports called "Coached into Silence" and his answer is a resounding yes. What happened here at Penn State was a classic case of pedophilia, the enabling of pedophilia, and the covering up of pedophilia to protect the institution and the people who should have been protecting the kids. Nothing unique here.
The relevance to MT, besides that we live and work here, is that more and more is being published to document the high prevalence of pedophilia, including stories about its purported prevalence in other athletic programs. If a high fraction, like 1 in 4 or 6, of children experience some sort of sexual abuse at the hands of adults, then not only do we have a social problem, but we have to re-think some of the commonly held views about a central area of biology: sex, and its relation to gender.
We've posted on this before. Sex in terms of chromosome number (XX and XY) varies, with a non-trivial fraction of the population having some different number of X and/or Y chromosomes. Or, they have mutational variants in their chromosomes that lead to unusual physical or reproductive traits. While most people are XX or XY and most have the genital and other bodily manifestations associated with the normal genotypes, there is variation and whether or what aspects one wishes to characterize as, for example, 'disease' is somewhat subjective. An evolutionary viewpoint would say that if the variant prevented successful reproduction it was dysfunctional or, in our cultural terms, 'disease'.
But that's not so clear, because many people have normal appearing chromosomes and normal appearing plumbing but bear no children despite having normal heterosexual relations. How do we characterize that? Here we tend to assume something psychological or cultural, and most of the time we'll allow it to be 'normal'. You are not 'diseased' if you stay single, marry but choose not to reproduce (or simply don't end up having children despite trying), or become a nun or priest. Or your tendency to honor monogamy, and so on.
Or, we have reasons in some instances to say that you have a physiological 'problem' or 'anomaly', that affects your sexual preference, behavior type ('gay' personality), or you look unusual for your sex, and so on. This will be attributed largely to your genes, which then could be argued to mean that you may have the plumbing but you really aren't 'male' or 'female'.
Then some would argue that for cultural or physiological reasons you are of a normal 'sex' but a different-from-typical 'gender'. Your behavior makes you act differently than you would for someone of your sex. Homosexuality would be one such variant. But stereotypical homosexual behaviors--call them gender behaviors if you will--are not always associated with homosexuality. Clearly there is variation and it's far from dichotomous. There is not just one set of two distinct genders, and what one wishes to call abnormal or 'diseased' is subjective to a great extent.
Pedophilia seems to be an example. Pedophiles have normal plumbing, are not gay, but prey on children (sometimes same-sex and sometimes opposite sex). The 'ped' part is what's different and doesn't put you in one of the other classes--it seems to be a class of its own. Psychologists apparently find that this is as ingrained as sexual preference, and is resistant to attempts to change it. It is, somehow, born of the person's 'genes' or their interaction with early environments in unclear but clearly complex ways.
Now, if pedophiles are so common that 1/4 of all children experience their assault, clearly most pedophiles also marry and reproduce. So are they 'diseased' in ways other than by social definition? And, yes, pedophilia is an entry in the DSM (the Diagnostic and Statistical Manual of Mental Disorders).
This is a legitimate question since the age of 'consent' varies greatly among human cultures. In turn that means that what we've been treating as a rare disorder is part of a continuum of variation that's not so rare at all.
What this would imply both about the biology of sex and gender, and about its evolution, is that we've been far oversimplifying the reality. As is our usual wont, here we'll point out that with such complex and gradual variation, there won't likely be a single gene 'for' the trait, like pedophilia, nor a variant that isn't also found in 'normal' people. It's an aggregate genotypic effect, of variants at many genes, interacting with environments--even if the result, like pedophilia, is built-in to the person when s/he is an adult.
So triggered by this scandal here at Penn State, and the facts it is evoking nationwide (along with the prior stimulus of the Catholic church and scout problems), this should force biologists to think more about the nature of sex and gender--so much at the heart of successful reproduction in a species, and at the same time, so variable.