Watch a monarch caterpillar shed its skin to reveal the chrysalis forming within it. YouTuber Allen Miller filmed this video in real time, six minutes that showcase the larva (caterpillar) to pupa (chrysalis) transformation. Details from Monarch Lab:
Just before they pupate, monarch larvae spin a silk mat from which they hang upside down by their last pair of prolegs. The silk comes from the spinneret on the bottom of the head. As it sheds its skin for the last time, the caterpillar stabs a stem into the silk pad to hang. This stem extends from its rear end and is called the cremaster.
You can clearly see that moment in this real-time transformation video by Jude Adamson. Around the seven-minute mark, the creature attaches its creamaster, the black stem, to the silk mat. The crumpled skin then falls away.
Raise your own monarchs with How to Raise Monarch Butterflies: A Step-by-Step Guide for Kids, or let them control the transformation over and over again with Fliptomania’s Monarch Butterfly Flipbook.
Watch more videos about metamorphosis on this site: Monarch Butterfly Metamorphosis in HD + The Monarch Manifesto, Why Is The Very Hungry Caterpillar So Dang Hungry? and what happens to a caterpillar inside its chrysalis? Bonus: This clip from the BBC’s Wonders of Life.