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Special | 3m 9s | Video has closed captioning.
What terrifying things go on in a chrysalis, and what dark role do genes play? In this episode, learn how a hormone wakes up a gene that triggers the transformation of a caterpillar into a butterfly -- from forming a chrysalis to liquefying the caterpillar to fuel the imaginal discs that form a butterfly.
Aired: 04/23/21
From:
(ominous music) - [Caterpillar] What do you see?
- You are changing.
- What kind of change?
What happens to me?
Tell me, tell me, tell me (rapid breathing)!
- A feast, you will have a glorious feast.
- Oh, well, that's not so bad.
What's on the menu?
I love food.
Are there friends around, do I look happy?
What am I eating, what am I wearing?
You know, I really like most any kind of plants, or sometimes I like flowers.
- Yourself, you are eating yourself.
- What, why would I do that to me?
That's not very nice.
- To transform into something uncanny.
Look, you know that you're, you know, you are a- - What?
- Oh come on now, you're a- - What?
- Caterpillar.
- Oh yeah.
- And, you know, one day you are going to, you know, change into a- - What are you talking about?
- Oh boy.
Here, watch this.
- [TV] You and your body.
Since your birth, the creature has been dormant inside you.
Only one thing keeps it from coming out, the juvenile hormone.
But since this hormone will run out, the genetic program is suppresses will awake, and the transformation will begin.
First, you will wrap yourself up in a chrysalis.
Then your cells will pop, releasing a rich slurry of proteins that will fuel the transformation.
- Oh gawh, I think I'm gonna throw up.
- Keep watching.
- [TV] Your enzymes will digest your entire body leaving behind imaginal discs.
(caterpillar vomits) Each disc is like a seed of a body part.
The genes inside disc begin a whole new program of growth that develop and fuse together to create the creature.
- I can't, I can't look.
Run, save yourself.
I'll eat you like I eat myself.
I'm a horrid monster.
Kill me, kill me.
No, don't kill me, but save yourself.
I'll eat everyone.
Oh look, a butterfly.
- Mm, that's what you'll transform into.
- [Caterpillar] Oh, I'm pretty and I have wings.
I won't be a horrible monster who eats everyone?
No, actually you won't really have a mouth at all.
You'll have a straw sticking out of your face, and you'll be on a liquid diet, licking up nectar, mud, poop, and decaying flesh.
(startled scream, body hitting floor, burp) (light, jazzy music)
The Gene.
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Animated Series
What the heck is a gene, anyway? This animated series won’t get you a PhD, but it does clear up a few mysteries about how genes work and what they might look like in the future. (Microscope not required.)
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