of all time.

But not for the reasons you might expect.

We're not talking about audio capabilities

or Bluetooth functionality,

but rather what they're made of.

Fungus,

bacteria,

and yeast.

It turns out,

mushrooms and a whole lot of other microbes

can produce materials that rival plastics and even leather.

And there is a team of scientists

and designers in Finland doing just that.

So, how did they take such

unusual materials

and turn them into something that could seriously

shake up the world of product design?

Nina Pulkkis: The Korvaa project started

actually with frustration.

Narrator: That's Nina Pulkkis.

She's the one who started Korvaa,

this whole headphone project.

Pulkkis: I was filming for a documentary

about microbes and synthetic biology.

But I was really frustrated

because I didn't have very good samples

of what you can actually do with microbes.

Narrator: So she set out on a mission

to see what could be made with them.

She gathered a team of

scientists, researchers,

and designers to make it happen.

Pulkkis: So, first of all, we started to think,

what kind of a product should we make.

Géza Szilvay: There was an idea about making

a pair of headphones.

Narrator: Headphones worked for a couple of reasons.

First, they are an instantly recognizable product.

Everyone has them.

Second, they require lots of leathers

and different kinds of plastics,

and those aren't always sustainable materials.

That's because oil and natural gas are two

of the main raw materials used to make plastics.

And in 2017,

368 million headphones were sold worldwide,

a number that's expected to keep growing.

That means a ton of plastic, leather,

and synthetic leathers, materials that rely heavily

on nonrenewable, nonbiodegradable resources.

Korvaa's process is a little different.

To start out, the headband is made of bioplastic.

To make that bioplastic, the team uses

plain old baker's yeast.

Through chemical processes, they turn that yeast

into a bioplastic substance.

That substance gets 3D-printed and hardened.

Next, the cushioned ear cups.

These are made from fungal proteins

and other plant-based materials grown in the lab.

Those materials get injected right into this mold.

And when they're dry, they look and feel just like foam.

Szilvay: Then the ear-cup covers are made

from fungal, leatherlike material.

It's made of mycelium.

One could think of it as root structure of mushrooms.

Merja Penttilä: Fungi grow in so-called

hyphal filamentous forms,

so they form long, long stretches.

So the material, in a way, grows itself.

Narrator: And those long stretches of roots

will take the shape of whatever you encourage them to.

The result?

Something similar to leather.

To make the inner mesh part,

the team created synthetic spider silk.

Spider silk is superstrong, lightweight, and elastic.

But spiders can't spin enough of it.

So they make silk in the lab,

without harming any eight-legged creatures.

By electro-spinning that silky material onto a flat surface,

they create a mesh material.

Then, all those parts get pieced together

to form a one-of-a-kind headset.

Manuel Arias Barrantes: I think people

have this perception

that fungi is something, like,

dangerous or, like, gross,

because it grows on food

also, that it's rotten.

But I think this is slowly changing as more

designers and companies are developing

materials from natural sources.

Saku Sysiö: For a lot of the

materials, we didn't know how to use them

and how to make them work in this project.

So that made it quite challenging and interesting.

Pulkkis: So it's really exciting to see

how this kind of small project grew

into something really much, much bigger

just by teaming up all kinds of different people

with different competencies

and completely different backgrounds.

Narrator: That team plans to commercialize

these unique materials so they can be used

in all sorts of products.

Would you wear these fungus headphones?