The healthy reason you ACTUALLY have sex

Scientists have figured out why we even bother with sex

Scientists have figured out why we even bother with sex

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Sex is ridiculous. Fun, sure. But if if you step back objectively from the bed (or kitchen floor, you libertine you!) an awkward theme emerges. The bumping, grinding and grunting that pepper the human sex act are as goofy and indecorous a display of basic animal behaviour as you'll find anywhere on the planet. Sex is also really impractical, from an evolutionary standpoint. Some organisms, after all, can simply clone themselves to procreate. Scientists have never been fully able to explain why we'd evolve to opt out of that efficiency and make babies the way we do. Until now.

Yes, some aspects for the practicality of coitus are quantifiable: when done right it's a decidedly pleasant physical expression of love (or lust), the health benefits are numerous, and there is that whole business of making babies to proliferate the species. But it's precisely here that other self-cloning organisms on earth seemingly have us beat. Dr Stuart Auld of the Faculty of Natural Sciences at the University of Stirling has been asking why sex even exists if we could've evolved to just spontaneously clone ourselves. Many creatures don't mate. They just will it and bingo, Bob's your uncle (important side note: who is really your uncle if you're cloning yourself though). When science knows plenty of organisms who sidestep the time and energy spent on mating rituals, foreplay and copulation altogether (Komodo dragons, starfish, and bananas, for example, don't have to date) why don't we? Bananas was a shocker. Are all the other fruit having crazy sex? You go, produce aisle. Also, this adds a nice scientific wrinkle to the innuendo of fruit emoji.

No matter. Auld asserts that this nut has long gone uncracked. "One of the oldest questions in evolutionary biology is, why does sex exist when it uses up so much time and energy?" Why can't we just 3D print ourselves into being without all the hooplah like some other species?  After studying the waterflea, yet another creature that is prone to parthenogenesis (science for sexless cloning), Auld's team thinks they have the answer: the sex act, it seems, has to do with better health. Rather, sex exists in most species on earth to bolster our babies against infection. Waterfleas were key to Auld's study and the real heroes of the finding (enjoy it waterfleas, may all creatures great and small get their moment in the sun, or petri dish). Female waterfleas can choose to clone themselves and make another female without the complications of a male suitor if it behooves them. But although female waterfleas can just will another them into being, they can also reproduce the traditional way, with a mildly expendable male waterflea. Ladies choice.

Before any of you get too excited about the prospect of evolving into a something that no longer needs access to social media or a proclivity for small talk to make modern mating happen, note that self-cloned waterfleas all shared a common trait: they were particularly sickly. Waterflea babies made the sexy way, on the other hand, were far better at fighting off infection. "More than twice as resistant" in fact. The virgin-birthed clones, when exposed to harmful bacteria, fell ill more easily and more often than their coitus-created siblings.

Auld believes that a broad mixing of genes makes stronger babies and is the real reason we get so thirsty for love. It also explains the reams of time and near nuclear levels of energy we and most animals on the planet spend on flirting, foreplay and fornicating (the trappings of courtship remain relatively static across species).


The applications of better gene sharing is at the core of IVF technology. Science is catching up with the way we procreate - it'll look different in tomorrowland. The hope of three-parent babies, a recent (albeit controversial) technological marvel of IVF, offer parents worried about passing on genetic illness to their brood a chance to free their offspring from once certain suffering. It would also give gay couples the option of having kids that share their DNA. Auld's findings line up with that tech. Sharing more DNA with our progeny will help make really healthy super babies. Which is awesome because it allows my Bourne Identity fantasies to remain intact a while longer.  

"Sex explains the presence of the peacock's tail, the stag's antlers and the male bird of paradise's elaborate dance. But if a female of any of these species produced offspring on her own, without sex, her offspring should come to dominate, while the other females watch the redundant males fighting and dancing. So, why are we not surrounded by clonal organisms?", Auld asks. Based on his recent findings, he also answers. Because sex, and the liberal mixing of our respective genetic makeups, populates the world with healthier babies.

Of course, we all know sex isn't just about procreation (sorry Catholicism). If it was, condom manufacturers, contraceptive medicine and sex toy companies would take a hard financial hit and never recover. And there isn't a waterflea's chance in hell of that happening any time soon.