Hi, you're about to get smarter in just a few minutes with Curiosity Daily from Discovery.

Time flies when you're learning super cool stuff. I'm Nate.

And I'm Callie. If you're dropping it for the first time

welcome to curiosity where we aim to blow your mind by helping you to grow your mind. If you're a loyal

listener, welcome back. Today you'll learn how a stiff gel could one day repair your knee, the dangers of AI when it comes to creating the world's next pandemic, and a brain scanning AI hit song machine.

Without further ado, let's satisfy some curiosity. Hundreds of

thousands of Americans report knee injuries every single year. It's super common and

it can be pretty hard to treat, but researchers may have come up with a solution.

I mean I feel like I know at least six people with any problems so I understand it's pretty common.

I think once you get to your 30s like in your friend group at least someone is going to have knee problems.

Yeah. Joints in the knee and the hip are incredibly complicated systems. They've got ligaments, bones, tendons, muscles, and cartilage.

Yeah, and it seems like if you get injured it's going to take forever to deal with.

But think about it, that joint, your knee allows us to support all of our weight as we walk and run and jump and hit the

gritty I feel like I'm too old to say that.

Yes, our knees allow us to

hit the gritty as the youngans say.

Anyway, one thing that makes the knee so incredible, but also really hard to fix is cartilage.

Okay, and that's the stuff our knees have in common with sharks.

Exactly. Shark skeletons are made out of cartilage.

Cardilage is this strong bendy stuff that makes sharks so graceful and sneaky and

it gives our knees a shock absorber. When the cartilage in our joints is injured we're missing a little

bit of that squish when we move and that can lead to crazy pain and friction and can even lead to

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