Nature's had a few billion  years to do what it does best.

So it only makes sense that we  humans would want to take advantage

of some of its greatest hits.

Taking inspiration from or mimicking structures  found in nature is called biomimicry.

And we do it a lot — for making things like  waterproof glues or wind turbine blades.

But there's another area that  draws inspiration from nature

that doesn't get as much credit: fashion.

Take dyeing fabrics, for example.

Thanks to the chemicals found  in many commercial dyes,

making a shirt a radiant shade of red can be toxic

to both the people dyeing the  fabric and to the environment.

But some of the most vibrant colors in  nature don't come from pigments at all.

They come from the structure of the material.

For instance, the morpho butterfly  has these vibrantly colored wings.

The iridescent blue color comes from  microscopic, shingle-like scales that

scatter certain wavelengths of light,  reflecting blue back to our eyes.

And two fabric manufacturers  have mimicked that structure

to create some stunning textiles.

Japanese fiber manufacturer  Kuraray created Diphorl:

a fabric made by spinning two  types of polyester together,

and then heat treating them  to make twists in the yarn.

Those twists sit in different  horizontal and vertical directions,

absorbing and reflecting light in  a similar way to the morpho wing.

Instant color, no dye required.

And another Japanese company, Teijin,

has taken the morpho wing idea one step  further with a fabric called Morphotex.

This fabric is constructed from 61  super thin layers of polyester or nylon.

And each layer is only around 70 nanometers thick.

By controlling the thickness of each layer,

researchers can change the  wavelength of light that's reflected:

either red, green, blue or violet.

But sometimes you want function  from your fashion, not just form.

Like, wouldn't it be great to be able to  wear a thin jacket in the depths of winter,

instead of being swallowed up in a  puffer jacket the size of a tent?

Well, polar bears might have the solution.  They are experts in staying warm, after all.

And that's thanks to a double-layered coat.

Close to the skin is a layer of short, dense hairs

and outside of that is a  set of longer guard hairs.

Those long hairs are hollow, which  makes them excellent at absorbing heat.

So instead of heat from the polar bear's  body seeping out into the cold Arctic air,

it's absorbed by the hairs, keeping the bear warm.

In fact, the heat is trapped  so effectively that polar bears

are practically invisible on infrared cameras.

In 2018, Chinese scientists developed  a technique for making fibers

with a similar structure  to polar bear guard hairs.

The fibers are packed with tiny pores,

making them basically hollow and able to  trap heat much like the guard hairs do.

But then, these scientists upped the ante.

They showed they could improve the  fibers by adding carbon nanotubes,

along with a power source.

These super thin, flexible strands can  be woven into the polar-bear-like fibers.

And a battery could heat the nanotubes quickly  and transfer heat easily to the fibers,

basically turning your sweater  into a portable, wearable heater.

Aside from keeping you toasty  warm, researchers think clothes

made from these fibers could almost  act like an invisibility cloak,

letting people evade infrared  cameras like polar bears do.

And finally, we've all got that favorite shirt.

You know, the one that's full  of holes you've had forever

and you just can't bear to throw it away.

It would be pretty cool if  that shirt could repair itself

so you wouldn't have to buy another  one for years, or maybe even decades.

Well it turns out, researchers are working on

a coating you can put on  fabric that would do just that.

First described in a 2016 paper, the  coating takes its inspiration from squid.

You see, squid have sets of tough,  serrated suckers called squid ring teeth

that they use for latching onto things.

Those teeth contain proteins that have a  unique nanostructure of repeating units:

some soft and wiggly, and some rigid.

Kind of like beads on a string,  but at a molecular scale.

And it's this structure — along  with some added heat and pressure —

that allows the coating to heal itself.

In squid, the protein structure gives the teeth

extreme strength and flexibility  for grasping onto prey.

When two proteins draw close to each other,

the rigid parts attract each  other and stick together.

The wiggly parts in between allow  them to line up in a neat array.

If coated on a piece of  fabric, the researchers say,

the proteins can join frayed parts back together.

And incidentally, while many self-healing  coatings don't work when wet,

this one has to be wet to work.

Not only did the researchers show that  fabrics including cotton, linen, and wool

could heal themselves in this way  — they could be self-cleaning, too.

They found that adding enzymes  to the squid-based coating

meant it could break down chemicals  that were applied to the fabric.

That would be great not only  for vintage t-shirt lovers,

but for workers whose uniforms need to  withstand abrasions or chemical spills.

But right now the best place to get  squid ring proteins is from squid.

Scientists have been able to get genetically  modified bacteria to make the proteins,

but they just can't pump them out  in the same amounts as a squid does.

Which is kind of crucial if you're talking about

manufacturing clothing on a larger scale.

So, fashion and function — nature just has it all.

So you can hardly blame us for wanting  to borrow some of its best moves.

Thanks for watching this episode of SciShow.

If you enjoyed it, you'll probably also  enjoy our podcast, SciShow Tangents.

In October, we did a Month of Monsters,  where we talked about real science inspired

by supernatural creatures like  ghosts and Frankenstein's monster,

and we've got more holiday-themed  surprises coming in December,

so keep an eye out for that!

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