Hi, I'm Danielle Dufault,
and you're watching "Animalogic: Second Nature."
[male announcer] At a salon in San Mateo,
a noted hairstylist feathers his nest with original ideas,
like putting feathers on milady's hairdo
and calling it "the parakeet."
[Danielle] Stylish hair may not be the best survival strategy,
but weaponized hair, that's another story.
Some otherwise harmless animals
have turned their hair or fins into spikes and needles
to defend themselves from potential predators.
[male announcer] In the present picture,
the pricking is the stimulus,
and the reaction is a quick withdrawal of the hand.
[Danielle] You're entering a world of pain.
These are nature's greatest spines and quills.
[♪♪♪]
Spines are one of nature's simplest
and most effective forms of self-defence.
They're found in plants, fungi, and of course, animals.
In most cases, spines make an animal more noticeable.
They're still vulnerable to large predators,
but the hunters know they'll take home a painful souvenir
if they decide to attack.
[male announcer] The energy used for the pricking is very small,
but the resulting reaction involves generally
a much larger amount of energy.
This is characteristic of all manifestations of irritability.
This is a form of aposematism
that makes the predators learn from their pain
and makes them less likely to attack another spiny prey item.
In mammals, the most common form of spine are modified hairs.
These long tubes of keratin are not only sharp,
but they are designed for maximum suffering and damage.
[male announcer] The porcupine depends on the growing tops of trees for food,
but as he eats, he deforms and may kill the tree.
[Danielle] Porcupines have some of the gnarliest quills
in the world.
A regular-sized individual has about 30,000 barbed quills,
each of them is perfectly engineered to puncture
and get stuck in flesh.
When cornered, porcupines will back into their predators
and whack them with their spikey tail.
Studies on North American porcupines
have shown that the barbed quills
only need half as much force to penetrate skin
than a quill that has had its barbs removed.
But it takes four times more force to take it out
than to take out a barbless quill.
Easy on the way in, hard on the way out.
Don't mess with porcupines.
[♪♪♪]
[Danielle] Their tiny cousins, the hedgehogs,
have a slightly different strategy.
Their quills don't break off like a porcupine's quills.
Instead, they're firmly attached to their skin
so that when they roll into a ball
they turn into adorably painful lawn urchins.
Hedgehogs have roughly 5,000 quills,
each of them so strong
that you could lift a hedgehog by a single quill
without breaking it.
Not that you should.
Only large predators, like badgers,
are able to get through their defences,
though foxes have been observed urinated on them
to try to get them to open up.
Echidnas have a similar strategy to hedgehogs
even though their lineages diverged
over 150 million years ago.
They roll into spikey balls to protect their soft bellies.
Their quills are thicker and more spread apart
than those of porcupines and hedgehogs.
They're also filled with a foam-like substance.
The result is an almost unbendable spine
that makes predators wonder
if Echidna meat is worth the hassle.
To many predators,
the answer is unfortunately, yes.
In Madagascar, the spiny tenrecs are the kings of spines.
Convergent evolution has made some species,
like the hedgehog tenrec,
look almost exactly like an actual hedgehog,
even though tenrecs are more closely related
to elephants than to other spikey animals.
Their spines protect them from predators like fossas,
and more amazingly, they also play a part in communication.
One species, the lowland streaked tenrec
has a patch of specialized spines
called stridulating quills
that can be rubbed against each other to produce sound.
This is pretty similar to the way crickets make their chirps.
[male announcer] Crickets are the canaries of the insect world.
They sing by rubbing their wings together.
Studies are still ongoing,
but it seems that spiny tenrecs use their sounds
to communicate with each other while foraging
and to warm predators that they're a painful snack.
This is the only known instance of stridulation,
the act of producing a sound
by rubbing different body parts together, in mammals.
I'll pause and let you make your jokes.
Wild, flagrant abuses of the God-given gift of sex.
[Danielle] Spines are a lot more common in reptiles than in mammals,
and here, keratin is the most commonly used material.
Found in Australia,
thorny dragons are easily the coolest spikey lizards.
They have spines all along their bodies,
and each of them is about the length of a thorn from a rose.
Their excessive spines protect them from predators
like large reptiles and birds of prey.
Thorny dragons are easy to catch,
but not necessarily the kind of thing
you want to go through your digestive system.
No.
[male announcer] Well, Bill,
now you know what might've caused your stomach ache.
Why you feel so bad.
Why you'll stay in bed till you feel better.
[Danielle] Their cousins and neighbours,
the bearded dragons, have evolved to look thorny.
Their tiny keratin spines are unlikely to harm any predators.
Their strategy consists of simply looking as unappetizing
and aggressive as possible.
If a predator calls their bluff, it's game over.
Across the globe in Texas,
there are horned lizards with a similar strategy.
The creatively named Texas horned lizard
have spines all along their bodies
to startle their predators.
The spines in their head are actually made of bone,
which gives them their name.
Though something tells me "dro-gone"
would be more appropriate.
If their spikes don't scare off their predators,
they can also shoot blood out of their eyes.
Most predators balk at the sight of blood jet streams,
but birds don't seem to mind, at all.
Like, they're actually kind of into it.
In the insect world, there are thousands of spiny species.
Several stick and leaf insects have spines
to accurately mimic thorny plants.
Several caterpillar species have thorns often equipped
with irritating agents to protect themselves.
[male announcer] A caterpillar is a growing up stage
in the life of a moth or butterfly.
The caterpillar hatches from the egg
and spends his time eating leaves.
[Danielle] My favourite though
is the giant prickly stick insect.
This Australian species can be up to 20-centimetres long.
If spotted by a predator, it adopts a threat pose,
making itself look like a scorpion
and displaying its spines.
Another badass prickly invertebrate
is the spine spider,
also known as the spined micrathena.
These tiny spiders are just about one-centimetre long,
but they make up for their small size
with amazing spines along their abdomen.
If you're ever hiking in the Rocky Mountains
and walk through a spider web, take a close look.
You might just be in the presence
of one of the coolest little arachnids.
Just make sure it doesn't go in your ears.
Finally, we got to the sea.
Many fish species have spines
which are often used to inject venom.
Pufferfish advertise their toxicity with little spikes.
A single pufferfish has enough venom to kill over 20 adult men,
and there is no antidote.
Lionfish are beautiful, but deadly.
[male announcer] Beneath those colourful fluttering draperies
are sharp spines loaded with a poison
which burns with an agonizing pain like liquid fire.
[Danielle] These killer queens have 18 venomous spines
that can easily kill predators.
Only some superpredators, such as bobbit worms,
morays, and sharks, can take them down.
In areas where they've become invasive,
such as the Caribbean,
they thrive due to the lack of effective predators.
Sharks are being trained to kill them,
but they would rather go for less spicy prey.
Last, but not least, we have the magnificent sea urchins.
There are over a thousand species across the world.
Their body plan is basically a sac of organs
surrounded by movable spines.
If touched by a predator or an unsuspecting beachgoer,
their spines perforate the skin.
Once inside, they break off and release venom.
This causes severe pain that can last for days.
So if you're ever at the beach, make sure to wear wading shoes.
Removing sea urchin spines from your toes
sounds like a crummy way to spend your holiday.
[male announcer] And is this a flower growing underwater?
Why it's alive!
A sea anemone.
[Danielle] Spines are just one of the many ways
that nature turns something as simple as hair
into engineering marvels.
I'm constantly amazed at the biological innovations
that over time completely change an animal's survival strategy.
Some of those changes are so ingenious
that they become the inspiration for human-made objects.
I'm no engineer myself, but I do love learning how things work.
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So what should I talk about next?
Please let me know in the comments
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Thanks for watching. Stay safe, and see ya!
[♪♪♪]
[male announcer] Leopard skins hold her down
while he completes the transformation
to leopard woman.
Is this the spot to say "It's mighty purr-dy"?