I mean it was just matter of time for the studies to start rolling in, but then I am not shocked, it's human nature. And before it became a "moral" issue it was just a simple issue of evolutionary survival. You have to procreate to have your species survive and we are hardwired to "do the deed" it's just part of our DNA!
And what better age to do it at from an evolutionary standpoint than from the ages of 16-20 something. Ages when we are young, strong and fit for the most part. It's pretty much just science.
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