Jack, you make an excellent point re men like Sandusky and many priests who sexually abuse underage boys.    Men have more opportunity to be alone with boys in settings like locker rooms and the recesses of churches without raising the suspicions of others than they do to be alone with girls in similar circumstances.   That fact alone could explain why Sandusky's victims (as far as we know) were all boys.    A lot of the hazing and "horseplay" that goes on in men's locker rooms, for example, may not be sexual in nature but physical enough and violative enough of 'normal' social boundaries that it allows a sexual predator to "test the limits" of what will be tolerated or even encouraged by the recipient.   There aren't a lot of settings where an adult male could wrestle with underage girls, flip their butts with a towel, or even be present in the girls' locker room while the girls were changing or showering. Who knows what direction Sandusky's lust for adolescents might have taken if that were not the case?

Paedophilia, clinically defined, is sexual attraction to prepubescent children, as has been pointed out. An adult having sex with young adolescents who have developed at least the outward appearance of sexual maturity or well on the way to it is "pederasty."    As undesirable as pederasty may be from a societal perspective and in terms of its effects on the adolescents in question, its motivation is neither abnormal nor pathological in itself; it is biologically quite normal for adult humans to be sexually attracted to young humans who have just reached sexual maturity or have the appearance of having done so.    (Big difference between finding a post-pubescent 16-year-old boy or girl sexually attractive, if you're an adult, and acting on that attraction.)

In Sandusky's case, it appears that at least some of his victims were not prepubescent "children." So I'm not sure whether a psychiatrist would classify his egregious behavior as a sexual perversion or just despicable behavior (comparable to his having committed statutory rape of teen-age girls).