Inside a Chrysalis, a Caterpillar Turns Completely Into Goo

If you thought metamorphosis was just a caterpillar growing wings like adding a new outfit, prepare to have your mind melted — much like the caterpillar itself. When a caterpillar seals itself inside a chrysalis, it releases enzymes that dissolve most of its own body into a liquid. Yes, it essentially turns itself into goo.

What remains from this self-inflicted soup are tiny clusters of cells called imaginal discs. These have been floating inside the caterpillar since it was an egg, quietly waiting for their moment. Once the rest of the body has been broken down into rich biological raw material, these discs use all those nutrients to rapidly build wings, eyes, antennae, legs, and everything else a butterfly needs. Nature's version of Lego, but considerably weirder.

The truly mind-bending part? Studies have shown that some memories survive the dissolving process. Moths trained to avoid a particular smell as caterpillars still avoid it after they've fully melted and rebuilt themselves. So somewhere in that puddle of goo, the caterpillar is still in there, taking notes.

If you're suddenly unsettled by the idea that butterflies are beautiful goo sculptures held together by an extremely good plan, you're not alone. You're just paying closer attention to nature than most of us ever did in biology class.