🦋 Life cycles

A caterpillar eats and eats, then wraps itself in a hard case called a chrysalis. Inside, its body breaks down and rebuilds into something new, and after a while a butterfly climbs out, ready to dry its wings and fly.

A tadpole hatches in water with a tail and no legs, breathing like a fish. Slowly it grows back legs, then front legs, its tail shrinks away and its gills change into lungs, until it can hop out onto land as a frog.

A snake's skin does not grow along with it, so as the snake gets bigger it grows a fresh new skin underneath and wriggles out of the old, tight one. The old skin often comes off in one piece, like peeling out of a sock turned inside out.

Inside the shell, a tiny chick grows bigger every day, fed by the yellow yolk. When it is ready, it uses a small bump on its beak, called an egg tooth, to crack the shell and push its way out into the world.