Human sexuality is obviously complicated. But it’s a mistake to think that, if you could somehow strip away human culture, sex would get simple. Even if you could find the simplest animal out there with a sex life, you wouldn’t find that imaginary simplicity.

This week I’ve written an essay on just such an animal, the worm Caenorhabditis elegans. With only a thousand cells in its entire body, the worm is unquestionably simple But it’s also arguably the best-studied animal on the planet. And yet its sex life–featuring self-fertilizing hermaphrodites with some males on the side–remains bizarrely mysterious.

I’ve written an essay for the online magazine Evolution: This View of Life on C. elegans, its strangely complicated sex life, and how that sex life–like