Editor’s note: Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. The larvae infest arthropods, such as ...

You’re not likely to witness a horsehair worm making its exit from a praying mantis, but if you do, it’s quite a sight. The spaghetti-like worm, under wet conditions, gradually wiggles out of its host ...