And you thought sex was some God-given pleasure to make humans happy. Pfsh, that's stupid. Sex is because we'd die from all the parasites, according to a new study. Asexual clones remain tasty and appealing to parasites who've already figured out their defenses. Sexual reproduction, however, continually makes unpalatable, hard-to-crack creatures. Sounds like everyone at the bar last night, amirite? Anyhow, it helps explain the reason the more-expensive sexual reproduction gets preference: after a while, the parasites take over otherwise.