Image: Veronique Brosseau Matossy
It frees its front legs and uses them to push its way out.
Although people commonly refer to butterflies emerging from their cocoons, the correct term for their delicate casing is the chrysalis, or pupa – in which the butterfly metamorphoses. (A cocoon, on the other hand, is the hard protective layer that a moth spins to cover and protect its pupa.) Prior to the butterfly emerging, its pupa becomes quite thin and transparent.