The entire shtick of most religions is shaming as many as possible into uniformity of thoughts and actions! So much easier for those at the top to control. If you can control the natural sexual urges of people by making them feel guilty for having them, you can control almost anything.

@Barnie2years A major part of theist religion, is the business of so called forgiveness of sin, over which they claim a, quite unnatural, monopoly. And if you want to maximize your forgiveness business, then you need to maximize guilt.

So anything that can be contrived to be a sin, is good fodder for guilt, however far you have to push the logic, until ultimately all of life is a sin, and the only thing not a sin, is wishing and working for the next life, over which the church also claims a monopoly. And eventually if they are successful everyone is obsessed with sin.

The fact is that it is opinion. "Research suggests"...... Theories are opinions that take in data but have no concrete proof. Thusly our species speculate which can lead to confirmation or dismissal.

Or interpretation.

All of the pieces fit together, and it explains all of the religious right and conservative culture war policies. Gay marriage and birth control are next on the list, like Thomas said, and we need to believe him on it.