"The Red Queen" is an excellent book pertaining to this and raising question in why humans have sex. Some argue it is the same as the appendix today. Left over from years of evolution, only there to "make" humans and animals breed. We can't just say "Hey, I want a new me" and then split cells and multiply, So this was a small incentive to get it done, and make sure humans try over and over again to get it to "take".
Also, never mind this is a week old.
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Transvestites are men who like to eat, drink and be Mary.
Let's do the Time Warp Again!
Hymen Destroyer