Originally Posted by Tha Q.

It's all innate, primeival desire driven by genetics. Humans are no different from animals in that regard. The only difference--some would argue--is that humans have a reasoning ability that other animals lack that allow us to display self-constraint. Sex drive is an ancient urge to reproduce and perpetuate the human species. That's why it's so strong. However, humans aren't the only animals believed to use sex for purposes OTHER THAN to reproduce. Some studies have shown that in certain ape species, sex is used to trade for other services, such as protection, as it is in prisons today.

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