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Hi Guys! Squeaks and I have been solving riddles all week, and I thought you might know this one: What starts its life as an egg, then it walks on many legs, and then it uses wings to fly? A butterfly! I bet you've seen a butterfly, and have you heard the saying "If you've seen one, you've seen them all?" That's not true with butterflies. There are over 17,000 different kinds of butterflies, and they come in all kinds of colors and patterns. But all butterflies have one thing in common - they all used to be caterpillars. 

So how did this, become this? Well, butterflies go through 4 stages in their life, that turn them into beautiful insects that we see flying around. Together, these 4 stages are called metamorphosis, which comes from the Latin words for changing shape. So what are these 4 stages?

Stage number 1, the egg stage. During the egg stage, a momma butterfly will fly from plant to plant, and when she finds the perfect one, she'll lay her eggs on it. Itty bitty teeny tiny little caterpillars live inside those eggs. When they're ready, these tiny little caterpillars chew their way out of their egg, and now we've reached stage number 2, the larva stage. 

The hungry caterpillar then crawls out of its egg, and then it eats its egg shell. And then it eats the leaf it's on. And probably the leaf next to it too. Did I mention the caterpillar is really hungry? All the food that the caterpillar eats helps it grow bigger and bigger until it's too big for its own exoskeleton. 

The caterpillar then moults its exoskeleton. But don't worry, it's already grown a new one underneath to replace it. The new exoskeleton is a little small, so to fix this the caterpillar gulps in air to expand itself, and then it waits, and lets its exoskeleton harden. 

But soon that new exoskeleton doesn't fit the caterpillar either. It moults and regrows its exoskeleton again and again, usually about 4 or 5 more times. After all that moulting and regrowing, the caterpillar's ready to take a break in stage number 3, the pupa stage. 

The caterpillar finds a sturdy branch or stem to hang upside down from. It moults its exoskeleton one final time, regrowing a new layer called a chrysalis. Inside the chrysalis, the caterpillar isn't really a caterpillar any more, but a pupa. A pupa is an insect when it's in between being a baby like a caterpillar, and an adult like a butterfly. 

The chrysalis has a hard shell to protect the soft pupa while it changes into its adult form. Inside it regrows its six legs and antenna, and adds wings. The pupa stays inside the chrysalis for 10 or more days. And then one day, the chrysalis moves, and it slowly cracks open, and the butterfly crawls out. 

Well, a really soggy-looking butterfly. Its wings are crumpled and wet. This is stage number 4, the butterfly stage. Once the butterfly's out of the chrysalis, blood will start pumping to its wings, helping them to straighten and dry out. Now the butterfly is ready to fly. 

Fly to some food! Ten plus days without food means this butterfly is ready to eat. Butterflies drink nectar, a sugary liquid found in flowers. And sometimes they like to eat rotting fruit, or even dead bugs. Butterflies take in their food through a long tube called a proboscis. Sort of like how we drink a milkshake through a straw. 

But they can't taste food with their proboscis. Can you guess what they do taste with? Their feet! When a butterfly lands on a flower, it can tell if the flower's sweet by tasting it with the tips of its feet. If they like the way it tastes, they'll drink the flower's nectar. 

Now, full of food to keep it strong, the butterfly is ready to, well, be a butterfly! And that's how a caterpillar becomes a butterfly. 

Now Squeaks and I are going to go outside and see if we can spot one! And I hope you do too, see you next time on SciShow Kids. 

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