Butterflies go through complete metamorphosis. Eggs are laid on the larval food plant and caterpillars hatch within a few days. The larvae have enormous appetites and do nothing but eat.

More information: Christin Manthey et al, Rapid growth and the evolution of complete metamorphosis in insects, Proceedings of the National Academy of Sciences (2024). DOI: 10.1073/pnas.2402980121 ...

We just develop. But flies, ants, moths, bees, and butterflies (including monarchs) go through complete metamorphosis, a four-stage process: egg, larva, pupa, adult.

Metamorphosis is the way some insects and amphibians change in their life. Rather than just growing bigger, they actually change form. Of course, butterflies are the most obvious of this group ...