Watch a Monarch caterpillar go through metamorphosis and become a gorgeous butterfly. In this awe-inspiring timelapse, we see ...

It's not a sack or a pouch; it's actually the caterpillar's own body. When it's time for the transformation to begin, the caterpillar's body ramps up production of a hormone called ecdysone ...

While the insect retains the form of a caterpillar, each moult merely exchanges the old cuticle for a similar new one. But when the time comes for metamorphosis, caterpillar clothes are exchanged ...