Killer Cold Deadly Pole to Pole


Killer Cold

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Transcript


LineFromTo

My name's Steve Backshall.

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And this is Deadly Pole To Pole.

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Ohhh!

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From the top of the world to the bottom.

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Whoa!

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Deadly places...

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deadly adventures...

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and deadly animals.

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And you're coming with me, every step of the way!

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Arghhhh!

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My crew and I have been to some pretty extreme places

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on our travels.

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I think we've got a bit too many sharks!

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That is phenomenal!

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But there's one environment that's deadlier than all the rest.

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It is Extreme cold.

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I'm not talking about your average winter day,

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but full-on, bone chilling, lethal cold...

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with the power to shut down our bodies...

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I'm not putting this on, I swear.

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..and even stop our very cells from functioning.

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It has more killer potential than any predator.

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Argh, let me out.

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To find out more, I've come to the Extreme Environments Laboratory

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at the University of Portsmouth.

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Here, I'm going to be shut in a room that's colder than your freezer

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and put in chilly water until my body starts to shut down,

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which is just the most ridiculous way to spend a morning.

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Whether in the frozen north or the barren ice fields of Antarctica,

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life in the world's freezers

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has found some ingenious ways of fighting off the cold.

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I want to explore the challenges they face,

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to learn what it takes to stay alive.

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First up, it's time for a dip.

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Inside this tank is water that's been chilled

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to 12 degrees centigrade and that is very cold.

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If I was on an expedition

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and I fell into water like this it would instantly become

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a survival situation and to find out how and why, I'm going to be

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dumped in here until it brings me

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right down to hypothermic.

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While I get my trunks on, my crew prepare me

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a nice cold bath.

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I've never been, kind of surrounded by quite

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so many different machines that go ping.

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Which is all a little bit nerve-racking.

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Taking a plunge in chilly water can be risky business.

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It has to be done under strictly supervised conditions.

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This is something you definitely shouldn't try at home.

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Cold water can suck life-giving heat away from our bodies much quicker

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than air.

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Chuck in icebergs and crashing waves, and a quick swim

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soon becomes a deadly dip.

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But there's actually one group of mammals that spend their whole lives

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in these conditions. I want to see how I shape up to them.

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So there are a number of things here that are monitoring my progress.

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I've got these pads which are monitoring my heart activity.

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I'm also wearing an internal thermometer so you'll be able

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to actually see what my core temperature is.

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If that starts to drop then I'm in real trouble,

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even a drop of one or two degrees could be very dangerous.

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-OK.

-Three, two, one. Here we go.

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Oooh.

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Oh, wow.

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It's colder than I was expecting actually.

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In a real immersion situation this would be the most dangerous bit,

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because your body is instantly, has a shock response to the water.

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So the first thing that you want to do is to breathe in

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very, very deeply.

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You can imagine if you were going into the sea,

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and there were waves and ripples, it would be very, very easy

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to swallow a lot of water in one go.

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And if that happened, that would probably be the end of you.

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Oh, oh, that's actually that is colder than

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I expected, I'm already getting brain freeze and I can feel

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my fingertips starting to go a little bit numb already.

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Less than a minute! That's not a good sign.

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My body's already starting to shake and shiver

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and generating a bit of extra warmth, just try and warm me up

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from the inside out.

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I really don't want to be in here for 40 minutes,

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it's just horrible already.

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Something that's happened straightaway is that all

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of my hairs on my arms and body have stood up, erect and they're trapping

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a layer of bubbles. Those bubbles

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contain air and they can be heated up by the temperature of the body

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to provide an extra layer of warmth.

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In a human being, because we're not very hairy it doesn't work

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very well, but in a lot of marine mammals, animals that spend

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a lot of time in the water, they have incredibly dense hairs.

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And the densest of all furs belongs to the silky sea otter.

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These bundles of fluff may look cute...

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but don't be fooled.

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Their pristine pelts are perfect

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at repelling the perils of chilly water.

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Essential if you want to hunt in icy seas.

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To find out why they need this hardcore insulation,

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I've headed to Alaska. Wow.

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There's a pretty good raft just over there.

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Oh my goodness that's unreal, wow.

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This is one of the best places on the planet to get up close

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with these mighty mustelids.

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They're just wonderful animals aren't they,

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like little floating bears.

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But there's only one way to really understand

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the struggles they face.

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I can't quite believe I'm saying this,

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but I'm going to need to get in and it looks really, really cold.

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The water is around a teeth-chattering 10 degrees C.

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That's even colder than the lab.

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Oh.

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Crumbs. It really quite takes the breath away. It's very, very cold.

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Of course the sea otter has such thick, dense fur,

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the densest fur of any animal that it can actually live in these

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waters with no problems whatsoever.

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Even with my wet suit though, this is a bit unpleasant.

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OK, I'm going to dive down, have a look.

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Within seconds I'm overcome by the cold.

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I can't believe they manage to live in this, day in day out,

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let alone scour the sea bed for tasty clams.

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It's an utterly alien world, and after just minutes,

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I'm ready to come out.

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Argh, my head.

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Oh, I've got the worst ice cream headache I've ever had.

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Phwoar, it's so cold. Oh.

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The sea otter, a hardy hunter, with a world-beating wet suit.

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Back in the lab, without the benefit of insulation,

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my core body temperature is starting to plummet.

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We're beginning to see this on our thermal imaging camera,

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which shows the heat of my body.

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Yellow and white areas are warm, while cold looks dark blue

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We human beings just are not built for this.

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Perhaps the reason that this is such a challenging environment is

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that water conducts heat away from the body more than 20 times

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more efficiently than air does, so you cool down

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faster than you would do in air, being in water like this.

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It becomes very uncomfortable, very quickly indeed.

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I've been in for seven minutes now and already I'm shivering

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quite a lot. The thermal imaging camera though shows that

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my head and face is still exactly the same as when I got in here

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but my hand, if I put that onto my face,

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you can see how that cooling works. Look at that.

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I look a bit like a clown it's kind of a bit strange.

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But you can see where the surface of the skin has cooled.

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In that case, not very much, so instead of being white or yellow,

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it's gone orange or red.

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But in my hand, completely black.

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Now this is one of the most important...

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I've just rubbed the end of my nose, it's gone blue!

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That is brilliant.

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That looks very, very strange indeed.

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We human beings, as mammals are, as you can see already,

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very, very poorly adapted to life in these kind of conditions.

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But we have some quite close relatives

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that under the skin are not too dissimilar to us,

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that deal incredibly well with temperatures like this.

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They have to deal with cold water every single day of their lives.

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And where better to find them than in the icy waters

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of the high arctic?

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Yes!

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There are splashes, waves,

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eruptions of white water,

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no more than about 30 metres off in front of us.

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Every once in the while, a white head breaks the surface.

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Every summer these waters are inundated

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with hundreds of curious creatures.

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Meet the beluga, the hardy white whale of the frozen north.

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There are very few marine mammals that could survive

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an entire lifetime in the Arctic Ocean.

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The way they manage this is through a thick layer of fat

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underneath their skin called blubber.

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This blubber allows the belugas to survive in waters

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that can drop to nearly minus two degrees C.

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It's a special kind of fat that can grow as much

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as ten-centimetres thick and make up half of their body weight.

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It's an incredibly efficient insulator,

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especially when the beluga is diving deep in arctic waters.

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Many marine mammals rely on blubber to keep them warm

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both topside and under the waves.

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Some of the blubberiest blubber is worn by the elephant seal

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of the southern ocean.

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Which can weigh more than a family car,

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keeping it warm in the worst weather.

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'Never mind a whole lifetime spent in winter water

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'my body's shutting down and I'm shaking like a leaf.'

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I'm not putting this on, I swear.

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This is really my shivering is going.

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Um, I don't feel as cold as I did before, though.

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But already, when I think about it,

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my brain's not working as well.

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Already now just...

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just speaking and trying to think about simple things is quite hard.

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'I may be losing my marbles

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'but things are about to get a whole lot worse.'

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At the moment there is still one part of my body that is warm -

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my face and my head because it hasn't gone under.

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Really, I suppose, I ought to go the whole hog.

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So let's just see what happens if I put my face in.

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OK, so now on the thermal imaging camera you can see already

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that my eye sockets are still very warm,

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I guess, because I had my eyes tight closed,

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but you can see all of the heat already leaching away

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from the skin on my face.

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The only way us humans really stand a chance of surviving cold water

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is to learn from the adaptations of marine mammals.

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Kitting ourselves up head-to-toe in hi tech insulation.

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But even then we can't match our aquatic cousins

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and are only able to stay in the coldest waters for mere minutes,

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before we have to come back to our own world.

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Without any of this protection, my time's nearly up.

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My body core temperature hasn't quite dropped by one degree C,

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but I think we're going to call it a day there

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and lift me out and see quite how extreme the effects have been.

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OK, Mike, take it away.

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You can see that...my...skin

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that was out in the air is still...yellow,

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which means it's not far off its normal temperature.

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But the rest of me is pretty much the same temperature as the water.

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So it's blue, my skin's dark blue, except under here in my armpits,

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where my skin's been clasped together and it's kind of

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insulated itself.

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But I'm just so glad to be out of there!

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'It's phenomenal how debilitating the cold can be for us humans.'

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Right, so if you could just hold that.

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No spinning, just twist that as fast as you can.

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'Unlike our marine mammal cousins,

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'even just a short dip can make the simplest tasks nearly impossible.

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'I can't feel a thing.'

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OK, fingers if you can, rather than twisting.

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'This is a real challenge.

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'Right, test done and it's time to warm up. I can't wait!'

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-Agh, argh!

-Careful.

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Ahh, that's so nice!

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-Oh!

-So you can bend your knees, keep your feet under, there you go.

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Ah!

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-It's good, isn't it?

-It's just amazing!

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That's probably the best bath I've ever had.

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'But I'm not done yet.'

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BATH TOY SQUEAKS

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Marine mammals certainly seem to have the ice cracked,

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but they're not the only subzero survivors on the block.

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Life on the land is just as tough.

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At the poles, temperatures can plummet to minus 93 degrees C.

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With some of the worst weather on the planet,

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you have a supremely savage scenario.

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Animals that live here use awesome adaptations to stay alive.

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To learn more about how they live life in the freezer,

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there's only one thing for it - I'm going to have to get in one.

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Right, we're now in a sealed room

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at about minus 18 degrees centigrade, which is

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about the same as the inside of your freezer at home.

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It's also the kind of entry level for extreme Arctic temperatures.

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At this temperature,

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most Arctic animals wouldn't even start shivering.

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And, for me, in all these clothes, it's actually pretty bearable.

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I could manage to survive here for quite a while.

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The big game changer, though, is if you get wind,

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and we can recreate that with this fan.

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Johnny, do you want to switch it on?

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FAN BLASTS

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So, this is now getting going,

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and it's blowing wind at about 10mph.

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At 10mph, minus 17 or minus 18 degrees C

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feels like minus 30 degrees C.

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For us human beings, at minus 30,

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exposed flesh will start to freeze almost immediately,

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so we have to protect ourselves.

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And we do it with an external hard-shell jacket

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made of special man-made fibres.

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Animals do it in a totally different way

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by having very thick, dense, external guard hairs -

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animals like the musk oxen.

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Weighing over 300 kilos,

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these musk oxen are built like fluffy tanks,

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with huge shoulders, strong, muscular legs,

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and a thick coat that can protect them from the worst Arctic storms.

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It contains some of the longest hairs in the animal kingdom.

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They are true cold weather champions.

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In Somerset Island, I managed to get my hands

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on the secret of their success.

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So, as human beings, if we want to survive

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in an Arctic winter, then we need to use layers.

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On the bottom, we'll go for a nice, warm fleece, and on top of that,

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something like a Gore-Tex jacket, which cuts out the wind.

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The musk oxen has something which is far more efficient.

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This is one of their pelts.

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So, on the outside, you have these thick, dense hairs,

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which cut out the wind.

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Underneath it all, you have this wonderful, soft underfur.

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It's almost like cotton wool, and that'll trap air close to the skin.

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This is far more efficient than anything that modern technology's

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managed to come up with. In fact, if I was to try and keep this on

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for just a couple of minutes, I would overheat.

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This is the secret to surviving in extreme cold.

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To show how vital all of these layers are,

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we have a thermal imaging camera over here.

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Once I start to take all this stuff off, you'll see a real change.

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So let's get rid of my windproof layer.

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It's already getting quite icy, look. Look at that! Hmm.

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Oh, crunchy.

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OK. Now we're getting down to proper insulation layers.

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What I've got here is a down jacket.

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The inside of this is filled with feathers, with down, like this.

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So, even today, in our hi tech era,

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we still use proper, real goose or duck down feathers

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as insulation inside this.

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There is nothing that human beings have managed to create

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that can have the same insulating properties as these feathers.

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Ducks and geese may use these insulating waterproof feathers

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to soar high above frozen landscapes

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and dive deep in icy Arctic waters...

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..but this is Deadly, and we're on the prowl for predators.

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The elegant great grey owl is one of the most well-insulated birds

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on the planet.

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It uses a down jacket to help it hunt in frozen forests,

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watching and listening for voles under the snow.

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Its feathers also allow it to pounce in stealth mode,

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helping it fly quietly into the kill.

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Unfortunately, for the purpose of this experiment,

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I'm not allowed the luxury of thermal feathers.

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OK, so, now, I'm going to lose my main insulating layer

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and this is when the thermal imaging camera

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is really going to start to see the difference.

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Ohhh, look at that! Already, yeah, I can see

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bright, bright orange, and as my hat comes off, look at that -

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it's almost white, my head!

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But the temperature we're at at the moment, minus 18,

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I really don't want to be like this for very long.

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Now I'm down to the base layer. This is incredibly important.

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It doesn't have to be very thick, but it's very tight to the skin,

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and it's incredibly important to insulating a thin layer of air

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very, very close to the skin.

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You'll find this in all Arctic animals,

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especially things like bears and foxes.

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To live in a place where seasons look like this,

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you need decent thermals.

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And a polar bear has some of the best

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thermal pants on the planet.

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Just like the musk ox, it uses guard hairs to keep out

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wind and snow.

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But its insulating underfur is so good,

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it allows it to stay warm on land and at sea.

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But it doesn't just survive here, it thrives,

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using its thermals to help it hunt on the ice.

0:21:550:21:58

Its neighbour, the Arctic fox, has even denser fur.

0:22:000:22:04

It can withstand the harshest winter storms

0:22:040:22:07

without the need for shelter,

0:22:070:22:09

even sleeping out on the ice,

0:22:090:22:10

using the thick thermal fur of its tail like a sleeping bag.

0:22:100:22:14

OK, and last of all, right down to bare skin.

0:22:190:22:24

Now, obviously, there are no land-living,

0:22:240:22:28

Arctic mammals that would do this.

0:22:280:22:30

You can see, for me... I mean, I am white hot. All that energy

0:22:300:22:35

is just instantly being lost through my skin. Perhaps as much as

0:22:350:22:39

90% of my body heat is just going to go instantly, straightaway,

0:22:390:22:42

from my skin. And if the wind was blowing,

0:22:420:22:44

I would be in very, very big trouble within a matter of minutes.

0:22:440:22:48

And I have to say, already,

0:22:480:22:50

I'm desperate to get my clothing back on.

0:22:500:22:52

There is, however, one last thing that Arctic animals can do

0:22:520:22:56

to make sure they're insulated,

0:22:560:22:57

and that is eating like you would not believe.

0:22:570:23:00

Our old friend, the Arctic fox,

0:23:010:23:03

takes advantage of warmer months to lay down

0:23:030:23:06

as much as half its body weight as fat

0:23:060:23:09

in preparation for the cold.

0:23:090:23:11

When the winter comes, it's not only got good insulation,

0:23:110:23:14

but calories to burn,

0:23:140:23:15

to fuel the fire to keep warm and stay alive.

0:23:150:23:19

ARCTIC FOX BARKS

0:23:190:23:20

Unfortunately, I'm nowhere near as good at piling on the pounds.

0:23:200:23:24

It's time for me to leave.

0:23:240:23:26

Argh, let me out!

0:23:260:23:28

It's pretty obvious that when it comes to surviving extreme cold,

0:23:350:23:38

us humans are rubbish compared to the birds and mammals

0:23:380:23:41

of colder climes.

0:23:410:23:43

Without the insulation of blubber and fat,

0:23:450:23:48

or the protection of feathers and fur,

0:23:480:23:52

we just don't stand a chance.

0:23:520:23:56

But there's one last cold weather strategy

0:23:560:23:59

that trumps all these tricks, and it has to be seen to be believed.

0:23:590:24:03

This is a surprisingly wonderful find.

0:24:090:24:13

It's a woolly bear caterpillar.

0:24:130:24:15

This is one of nature's great survivors.

0:24:150:24:18

These caterpillars live in the frozen north

0:24:200:24:23

and have to make it through harsh Arctic winters.

0:24:230:24:26

The way they do this is by completely

0:24:260:24:30

shutting down their bodies and freezing themselves solid.

0:24:300:24:34

But when the summer comes, these hungry caterpillars

0:24:340:24:37

rise from the dead, and are able to munch on

0:24:370:24:40

the freshest Arctic veg.

0:24:400:24:41

A caterpillar that can become an ice pop may sound impressive,

0:24:430:24:47

but it's a pretty simple animal.

0:24:470:24:48

There's a far more complex critter that can pull off this trick,

0:24:480:24:52

and it's my supreme ice-cold survivor.

0:24:520:24:55

The wood frog lives in North America,

0:25:000:25:02

where the winters are harsh.

0:25:020:25:04

Its range may even stretch up into Alaska, further north

0:25:040:25:08

than any other frog.

0:25:080:25:10

Cold-blooded creatures struggle to survive in cold weather,

0:25:100:25:14

so this frog takes extreme survival to another level.

0:25:140:25:17

When the winter temperatures start to drop,

0:25:200:25:23

the wood frog takes refuge underground.

0:25:230:25:25

As it gets colder still, the icy frost penetrates the soil.

0:25:280:25:33

Being cold-blooded, our freaky frog starts to freeze.

0:25:330:25:38

All living things contain water in their cells.

0:25:400:25:44

As this water freezes,

0:25:440:25:45

it forms spiky ice which can rip these cells apart.

0:25:450:25:49

But the frog uses clever chemistry to protect itself.

0:25:490:25:55

It packs its cells with sugars,

0:25:550:25:57

which force the ice to form in places where it can't do any harm.

0:25:570:26:01

With no breathing, no movement, and even no heartbeat,

0:26:090:26:13

the frog should be dead.

0:26:130:26:15

But the sugars stored in its body provide just enough

0:26:160:26:19

energy to keep the cells alive through the deepest parts of winter.

0:26:190:26:23

Frozen in time,

0:26:260:26:28

this incredible frog can survive for weeks on end.

0:26:280:26:31

But even with all its vital functions on hold,

0:26:310:26:35

it hasn't croaked it - there's life in the old frog yet.

0:26:350:26:38

When spring arrives and the temperatures start to rise,

0:26:410:26:45

the frog's body begins to thaw.

0:26:450:26:47

The defrosted heart muscles kick-start it back into action

0:26:470:26:52

and blood starts pumping around the body.

0:26:520:26:54

The once-frozen frog is almost completely back to normal

0:26:540:26:58

within just 24 hours.

0:26:580:27:00

And it hops to it, taking advantage of being the only frog in town,

0:27:000:27:06

free to gobble up insects ahead of the competition.

0:27:060:27:09

This Frankenstein frog has to be the ultimate subzero survivor.

0:27:100:27:16

Instead of fighting off the cold with blubber and fur,

0:27:160:27:19

it embraces it, almost making itself dead in the process.

0:27:190:27:23

Any environment that forces an animal to go to lengths like that

0:27:250:27:29

has got to be deadly.

0:27:290:27:31

Join me next time for more Deadly Pole to Pole.

0:27:380:27:41

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