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Details after the show.

♪ [crickets chirping] Razor sharp, designed to impale, and next to impossible to remove.

The fearsome creature that wields these weapons?

Aw, look at that face.

A North American porcupine may be slow as she plods along.

She can take her time looking for tasty leaves and bark or munching on acorns.

She doesn't have much to worry about.

That's because she's packing 30,000 piercing quills.

But hold on.

Those white things aren't quills.

They're just extra long hairs, decoys to make her look even more spiky.

The real quills are underneath.

They're white, too, but usually hidden under that dark fur.

Most animals learn: Do not mess with porcupines.

A porcupine normally keeps its quills flat against its body.

But when threatened, it bristles, showing off an area on its backside where the quills are the densest, called the rosette.

And it stinks.

The quills are coated in a waxy grease that puts off a pungent musky smell, unique to porcupines, that says, "Back off."

But if that's not enough, she uses her tail to slap anyone who gets too close.

Watch this.

She didn't shoot her quills out-- that's a myth.

The quills don't release easily unless they hit something and get pushed in first.

They're super sharp-- sharper than this hypodermic needle.

And check this out-- the tip is covered in microscopic, backward-facing barbs.

When you try to remove it, the barbs fan out, keeping the quill lodged in.

Yee-ouch.

If you get a bunch in an unlucky spot, like your mouth, that makes it hard to, you know, live.

But even though they're super painful, getting stuck with a quill doesn't usually lead to infection.

The quill's grease acts like a natural antibiotic, inhibiting the growth of some dangerous bacteria.

Maybe it's because porcupines are actually pretty clumsy; they've been known to accidentally quill themselves, falling out of a tree, maybe.

Researchers at Harvard are now looking at these quills for inspiration.

Surgical staples that doctors use to close wounds curve in under the flesh to stay put.

That causes damage on the way in and leaves room for bacteria to take hold.

So what about a staple with barbs, like a porcupine quill?

It could make a smaller wound and stay put without curving.

That could keep infection out and speed up healing time.

Then, it just dissolves.

Pretty sharp, right?

That's something about this spiky little fuzzball that anyone could love.

Hey, couple things before you go.

Did you know that every single Deep Look episode has original music?

Come on over to our Patreon site to meet our composer, Seth Samuel, and hear how he creates the music for the show.

Also, definitely check out Sound Field, a new show about music from our partner network, PBS Digital Studios.

Sound Field breaks down our favorite songs, from Bach to Beyoncé.

Links are in the description.

Thanks.