At a superficial level, sexual jealousy is arguably one of the most counterproductive emotions we have evolved to experience. Think of all the hours we humans waste pining over stolen partners or unrequited love, not to mention the devastation caused by crimes of passion. Plus, from an evolutionary perspective, surely more people having sex would mean more people, period. So why do we get so upset over what someone else does with their naughty bits?
-Vice
