Deadly Top 10s (2009) s02e03 Episode Script
Extreme
Welcome to my Deadly Top 10.
Whoa! A chance to choose the most extreme, mass-attacking, defending, airborne and super-sensing animals on the planet.
Quick, quick, quick! All deadly in their own world, and occasionally deadly to me.
Argh! Who do you think will be number 1 of the Deadly Top 10? In this show, I'll be counting down deadly hunters that survive in some of the most extreme places on the planet.
In searing heat, at dangerous depths, inside creepy caves and even in the coldest places on Earth, these predators make surviving look easy.
So, buckle up as we take a rollercoaster ride around the world, finding my Deadly Top 10 extreme! Hold on tight, because at 10 is the high-altitude Himalayan snow leopard.
Their home is the extreme cold, dry cliffs of the Central Asian mountains.
Over 5,000 metres above sea level, the steep, broken terrain is harsh and forbidding, and the air is thin, with little oxygen.
But the snow leopard is perfectly adapted to slink over loose rocks and scramble up and down vertical faces, on the hunt for prey.
Their camouflage is incredible.
They blend in without a trace.
This is probably our best chance of seeing things.
We're just at the tree line, and all around us, the hillsides are open.
So we can see for a long, long way.
Oh, hang on! There's a huge herd of animals.
For an ambush predator like a snow leopard, this is kind of easy game.
Snow leopards are built to go off-road.
Their short, stocky forelegs and massive paws help get a good grip, while their long back legs give them a spring in their step for launching an attack.
The long, furry tail stores fat and, crucially, helps with balance as they flow over the slopes.
They might be at home here, but it's hard work for me, trekking at this altitude.
You have to watch your step as the locals here in Bhutan know all too well.
A wild sheep has been killed just behind their house.
Could you show me where this happened, and maybe if there is any sign there? He's going to show us the spot.
OK.
Wow! OK.
This is all rather unpleasant.
Very, very strong smell.
It's still, from the waist up, very much intact.
It's just eaten the back half, and most of the rest of it is gone.
This big cat may be beautiful, but it's also deadly.
They can take down prey four times their size.
They stalk into position, then ambush from above.
Leaping up to 14 metres, they'll chase their prey down almost vertical cliffs.
They kill by biting the neck, and drag their prey to a safe place to eat it.
The snow leopard makes life on the edge look effortless.
From sheer mountain sides to searing deserts, next at 9.
It's a prickly, pointed predator - the spiky thorny devil.
Australia's outback is hot.
Seriously hot! And very, very dry.
Sometimes, it doesn't rain for years.
On walkabout here, I'll need to drink four or five litres of water a day to stay healthy.
So how do other animals survive this extreme? Meet the rather weird-looking thorny devil.
Now, all these very distinctive thorns along its back and its tail are actually modified scales.
They're quite sharp and pointy, and certainly if a dingo was to get a mouthful of it then it would probably drop it.
But aside from being a great defence against predators, this lizard's strange skin actually helps it collect water in this arid land.
Thorny devils exclusively eat ants, up to 2,000 in a meal.
And licking them up one at a time is pretty thirsty work.
Water is a vital resource in the outback.
The thorny devil's scaly skin doesn't sweat and instead is covered with a network of thousands of tiny grooves that work like straws, sucking up moisture from the ground.
The water creeps between the scales, towards the lizard's waiting dry mouth.
This way, the thorny devil can absorb water during rains, catch droplets of dew, and even soak up a drink from damp sand.
A pretty clever way of quenching your thirst in an extreme dry desert.
Now, you might be surprised that the deadly predator at number 8 is a plant.
It's the strange carnivorous pitcher plant.
This odd-looking family of flora are found in extreme locations where the soil is too poor in minerals, too sandy or acidic for most plants to survive.
As they can't get their nutrients from the ground like normal, these plants have developed a deadly strategy.
They catch and devour insects.
Leaves on the plant swell and grow into pods called pitchers which, when they open, are often filled with a special, syrupy liquid produced by the plant.
Like a deadly swimming pool, creatures that fall in will drown and are digested by the juices.
To lure in their prey to a watery grave, the plants are brightly coloured, often sweet-smelling, and ooze nectar from the underside of their lids, all a hit with the locals.
But the edges of the pitcher have slippery, waxy sides, a one-way ticket to trouble.
Ants don't have armbands, so quickly drown in the plant's predatory puddle.
Their bodies decompose into a soup, which is absorbed by the plant, a great source of nutrients that the plant would normally get from the soil.
Energy needed to grow yet more deadly pitchers.
By developing this carnivorous strategy, pitcher plants can thrive in extreme areas where other plants never could, even in mid-air with no soil at all.
Fantastically fatal flora! So, three down, and we've already seen some extreme survivors.
The mountaineering snow leopard, the sucking skin of the thorny devil, and the rather ravenous pitcher plants.
As we count down the list, what could beat these three to number 7? Take a deep breath, because it's an odd-looking, swampy river monster.
It's the lungfish.
These eel-like predators have evolved to be perfectly adapted to life in stagnant, boggy lakes and marshes.
They're well camouflaged, but I'm hoping we'll catch one here in the shallows.
My friend here has managed to net me a lungfish.
Now, most fish would really object to being treated like this, but the clue to why this one is actually doing OK is in the name, lungfish.
It not only has gills here, for breathing in the water, but it also has lungs.
So, that gulping sound you can hear there is it breathing oxygen in the air.
One of the most unusual things about the lungfish is what happens if all this water dries up.
Lungfish have evolved to cope with the most extreme environment for any fish - drought.
In parts of Africa, a lack of rainfall means that swamps and rivers can dry up completely.
This means certain death for most aquatic animals, but the lungfish has a plan.
It burrows down into the mud, using its mouth to excavate a chamber.
Overhead, the mud dries hard, almost like concrete.
But inside its burrow, the lungfish exudes a thick, slimy covering that dries hard around it, forming a waterproof, protective cocoon.
Mummified this way, it can survive for months, or even up to four years, entombed in mud.
Some lungfish have even found themselves incorporated into mud brick houses.
The lungfish stays alive by breathing air and slowing its metabolism to one 60th of its normal rate.
It barely moves, and looks as if it's dead, but it holds out until the rains come.
At the first sign of moisture, the lungfish begins to stir.
Its slime cocoon and muddy burrow soften in the rain.
The fish seems to come back to life and slithers straight for the water.
Due to its slimy shutdown technique and ability to breathe air, the lungfish can survive the most extreme droughts.
A fish out of water? No problem! Next, at 6, are some creatures who survive and thrive in constant darkness.
Good to go, Steve.
We're good to go.
Over.
Caves are dark, damp and generally inhospitable places.
Up in the roof of the cave, with the bats and the birds circling around you, it's kind of like paradise.
And down here is a kind of hell.
But there are some deadly creatures that absolutely love it.
It's home to bats, bugs and weird, scuttling creepy-crawlies.
This, possibly, is one of the nastiest places on the planet.
Caves are extreme environments, as food is hard to come by.
There you go Ooh! That one just ran over my hand! Anything that lives here has to know how to survive or hunt in pitch darkness.
The tiny starlights in the roof of this cave in New Zealand might look lovely, but they are, in fact, the lethal lures of the fungus gnat glow worm.
To try and catch a meal in this harsh cave environment, the fungus gnat larvae employ a clever hunting technique.
They hang sticky threads of mucus-covered silk from the ceiling, like a three-dimensional web.
In the still air of the cave, each gnat larva can manufacture up to 70 separate strands of silk, producing a dense curtain of snares that hang down like beautiful, beaded chandeliers.
Belching beads of gluey mucus onto each strand of silk turns them into exquisite lethal weapons.
Spinning more filaments maximises the chance of catching a meal, as food is scarce.
Each gnat larvae emits a pale blue light from the tip of its abdomen, a chemical beacon that's clearly visible in the surrounding darkness.
It proves irresistible to any insects that stray into the cave.
Mayflies and midges hatching out of underground streams flutter upwards towards the lights, like moths to a flame.
The fungus gnat's snares, invisible from below, are devastatingly efficient.
In an extreme place like this, where there isn't much food to go around, a successful hunting strategy is vital.
Once caught, the fly's struggles only entangle it further.
The larva slowly slimes its way over and begins to winch up its meal, bead by slimy bead.
The prey is then sucked dry and chopped up into tiny pieces to be eaten.
Not a scrap is wasted.
By using silken threads, mouthfuls of mucus and a dazzling tail light, this slimy creature can fish for a living in one of the most extreme cave environments.
We're halfway through the countdown, and so far, we've seen a big cat that lives on the toughest mountain slopes, the desert devil's smart skin, carnivorous pitcher plants, a drought-busting lungfish and some fatally attracting glow worms, all brilliantly adapted to survive extreme conditions.
So, who could beat them on the list? There's a battle for the number 5 slot.
Two foxes are going head to head.
It's the arctic fox versus its sandy cousin, the fennec fox.
First up is the fennec fox, who survives in the extreme heat of North Africa's deserts, where the daytime temperature can reach 43 degrees.
This little fox has some clever adaptations to survive the high temperatures of the Sahara.
It spends much of its day in its burrow.
The freshly dug sand is cool and a great place to hide from the piercing sun.
It also has giant ears.
These are packed full of blood vessels and work like radiators, pumping heat away from the body.
No water in the desert is also no problem for the fennec.
It fills its diet with juicy grubs and succulent snakes even if they are quite a mouthful.
They rarely need to drink water and never sweat.
So, the desert-digging, big-eared, snake-munching fennec fox makes living in extreme deserts look like a walk in the park.
How does his northern cousin match up? In the spring, the arctic fox is a lean, mean killing machine.
It fills its face with seabird chicks and stores food for later, as the arctic winter is going to be tough.
Temperatures plummet to minus 40, 50 or even 60 degrees.
And the arctic fox dresses for the weather, donning a snow suit twice as thick as its spring coat, one of the best insulating furs of any mammal.
The arctic fox is quite literally the polar opposite of the fennec, with small ears, short legs and a fat, rounded body for keeping in the heat.
Its incredible white fur is its weapon against cold, and by curling up into a ball, its tail acts like a duvet over its face.
The fox can keep its body over 50 degrees warmer than the surroundings when snuggled up like this.
It has furry feet, like snowshoes, and special blood vessels in the pads to stop its feet freezing.
Food is hard to come by in winter, but the adaptable fox can even survive on scavenged scraps.
So, both clever canids are pretty extreme, but which one will take the number 5 slot? For me, it has to be the gorgeous arctic fox, surviving freezing temperatures with its oversized overcoat.
A super furry animal! From the polar winter to the desert heat, next at 4.
It's the spoor spider, the master of the dunes.
The sun here in the Namib is utterly scorching.
It can be a bit like wandering around in a sauna, and the sun's rays are soaked up by the surface of the sand, which is unbearably hot.
Mind you, if you dig down just a short way the sand's still cool.
There's lots of animals here that use both these things to their advantage.
They'll bury down beneath the sand to stay cool during the daytime, and they can use the heat on the surface of the sand as a weapon.
Urgh! Our next animal doesn't pose any threat to me.
Wait for us! But the same definitely can't be said for the local ant population.
Ah! We've been looking a lot at tracks and signs of animals, and under here is the hiding place of a very special hunter.
See if we can get it out.
Wow! I think I might have him! There he is.
This is a spoor spider.
He's only very tiny, but he's a very ferocious and really quite clever little hunter.
The spider uses the heat of the sand to kill its ant prey.
Unlike most spiders, the spoor spider spins their web on the ground, carefully weaving together fine grains of sand.
They then flip themselves under this silken mat and, protected from the sun, begin to construct a burrow in the cool layers beneath.
Our thermal camera shows the difference in temperature.
Then Bang! It rockets up its burrow and grabs the ant with one super-strong leg, clamping it down against the baking-hot sand until it actually cooks the ant alive.
It then drags the body back into its burrow to be devoured.
So, by adapting its web to be a sunshield and the perfect ant trap, the spoor spider can take down feisty prey twice its size, using the desert heat to barbecue its meat.
The competition is hotting up, and if that desert hunter got you in a sweat, the animal at number 3 is super cool.
It's the emperor penguin.
Surging out of cold, Antarctic waters, emperor penguins are ready to start their breeding season.
Males have been hunting at sea, and are glossy and fat with fish.
But they need to be, as they're setting off for the start of one of the most extreme trials on Earth.
They trek up to 100 miles on full stomachs, across the frozen ice, to reach their colony.
Hours of painstaking plodding.
Here, they pair up with their mates for the season.
The female hands over the egg, and the tag teams switch places.
It's now Daddy Day Care's sole job to keep the egg safe and warm inside his pouch for two months until it hatches.
And it's about to get a lot colder.
Extremely cold! As the sun drops below the horizon and winter sets in, blizzards drive the temperature down.
In order to survive, the males are forced to hunker down, shuffling together into a group for warmth, taking it in turns to be on the edge, being buffeted by the vicious winds.
They turn their backs to the gales and tuck their beaks down to conserve warmth.
If the huddle breaks, even for a moment, precious heat escapes.
Antarctica is the coldest, windiest place in the world.
The air temperature can drop to minus 60, with winds of up to 120 miles an hour.
By the end of the winter, the male hasn't eaten a thing for four months.
Not only has he survived the coldest, darkest winter on the planet and lost around 45% of his body weight, but he still has the energy to provide the tiny chick with a mouthful of vital food.
And surviving this extreme is all worth it, so the chicks are born early enough in the season that they can grow big and strong before they head out to sea to hunt.
So, what can be more extreme than surviving the coldest, darkest winter on Earth? In at 2 is the largest toothed hunter in the world, the sperm whale.
This giant stalks its prey in the mysterious depths of the oceans.
Big males can be 20 metres long and weigh 45 tonnes.
That's about as heavy as six elephants! And big animals have big appetites.
A sperm whale needs to eat a tonne of food every day.
But the reason why the sperm whale is so extreme is that its dinner lives over a mile down, in the crushing, pitch black of the deep sea.
It's the deepest-diving of all mammals.
Before it submerges, the whale breathes out, a trick to stop its lungs from being damaged under pressure as it dives.
Then, with a flick of its massive tail, it descends at 100 metres a minute.
It can hold its breath for over an hour.
The pressure at a mile down exerts a force the same weight as ten jumbo jets.
But the sperm whale's skeleton is designed to bend, not break.
Its heartbeat slows to a third of its normal speed.
Now, with its body buckled by pressure, no air in its lungs, and its heart barely pumping, it starts to hunt in complete darkness.
The whale uses echolocation to hunt for squid underwater.
Like a submarine, he sends out clicks and calls that bounce back to build up a picture of its surroundings.
And, once it's had its fill, the whale surges to the surface to breathe.
By being equipped to go where other mammals can't, the sperm whale gets a rich fishing ground all to itself.
Now it's time for a refreshing reminder of the extreme predators we've seen so far in our 10 to 2 countdown.
The rock-climbing snow leopard makes crumbly cliffs look cosy at 10.
Knobbly 9 is the thirsty thorny devil.
Drowning out the competition at 8 are the pitcher plants.
Slippery 7 is the slime-covered lungfish.
The fatal fairy lights of the glow worm are at 6.
Staying alive at 5 is the all-white arctic fox.
Our ant-snatching spoor spider is at 4.
Weathering the world's worst winter at 3 is the emperor penguin.
And diving in at 2 is the phenomenal sperm whale.
So, what on earth is going to top all of that to the number 1 in my Deadly Top 10 extreme? It's the wood frog, and trust me, they have the ultimate survival strategy.
The wood frog lives in North America, where the winters are harsh.
Its range even stretches up into Alaska, further north than any other frog.
Cold-blooded creatures struggle to survive in cold weather, so this frog takes extreme survival to another level.
When the winter temperature starts to drop, the wood frog takes refuge underground.
As it gets colder still, the icy frost penetrates the soil, and being cold-blooded, our toad-in-the-hole starts to freeze.
The frog uses some clever chemistry to protect itself from spiky, dagger-like ice crystals damaging its insides.
It packs its cells with sugars, which work like antifreeze.
Using glucose is a pretty sweet trick as it prevents the frog's cells from being destroyed by ice crystals, which form between the cells and in the bloodstream instead.
With no breathing, no movement and even no heartbeat, the frog should be dead.
But the sugars stored in its body provide just enough energy to keep the cells alive through the deepest part of the winter.
Frozen in time, this incredible frog can survive as an ice pop, with 65% of its body frozen solid for up to four weeks.
But even with all its vital functions on hold, there is life in the old frog yet! When spring arrives and the temperatures start to rise, the frog's body begins to thaw.
The defrosted heart muscle is kick-started back into action, and blood starts pumping around the body.
The once-frozen frog is almost completely back to normal within 24 hours and hops to it, taking advantage of being the only frog in town! So, that's my Deadly Top 10 extreme done! Don't forget to join me next time for more Deadly Top 10s.
Who's going to be the next deadly number 1?
Whoa! A chance to choose the most extreme, mass-attacking, defending, airborne and super-sensing animals on the planet.
Quick, quick, quick! All deadly in their own world, and occasionally deadly to me.
Argh! Who do you think will be number 1 of the Deadly Top 10? In this show, I'll be counting down deadly hunters that survive in some of the most extreme places on the planet.
In searing heat, at dangerous depths, inside creepy caves and even in the coldest places on Earth, these predators make surviving look easy.
So, buckle up as we take a rollercoaster ride around the world, finding my Deadly Top 10 extreme! Hold on tight, because at 10 is the high-altitude Himalayan snow leopard.
Their home is the extreme cold, dry cliffs of the Central Asian mountains.
Over 5,000 metres above sea level, the steep, broken terrain is harsh and forbidding, and the air is thin, with little oxygen.
But the snow leopard is perfectly adapted to slink over loose rocks and scramble up and down vertical faces, on the hunt for prey.
Their camouflage is incredible.
They blend in without a trace.
This is probably our best chance of seeing things.
We're just at the tree line, and all around us, the hillsides are open.
So we can see for a long, long way.
Oh, hang on! There's a huge herd of animals.
For an ambush predator like a snow leopard, this is kind of easy game.
Snow leopards are built to go off-road.
Their short, stocky forelegs and massive paws help get a good grip, while their long back legs give them a spring in their step for launching an attack.
The long, furry tail stores fat and, crucially, helps with balance as they flow over the slopes.
They might be at home here, but it's hard work for me, trekking at this altitude.
You have to watch your step as the locals here in Bhutan know all too well.
A wild sheep has been killed just behind their house.
Could you show me where this happened, and maybe if there is any sign there? He's going to show us the spot.
OK.
Wow! OK.
This is all rather unpleasant.
Very, very strong smell.
It's still, from the waist up, very much intact.
It's just eaten the back half, and most of the rest of it is gone.
This big cat may be beautiful, but it's also deadly.
They can take down prey four times their size.
They stalk into position, then ambush from above.
Leaping up to 14 metres, they'll chase their prey down almost vertical cliffs.
They kill by biting the neck, and drag their prey to a safe place to eat it.
The snow leopard makes life on the edge look effortless.
From sheer mountain sides to searing deserts, next at 9.
It's a prickly, pointed predator - the spiky thorny devil.
Australia's outback is hot.
Seriously hot! And very, very dry.
Sometimes, it doesn't rain for years.
On walkabout here, I'll need to drink four or five litres of water a day to stay healthy.
So how do other animals survive this extreme? Meet the rather weird-looking thorny devil.
Now, all these very distinctive thorns along its back and its tail are actually modified scales.
They're quite sharp and pointy, and certainly if a dingo was to get a mouthful of it then it would probably drop it.
But aside from being a great defence against predators, this lizard's strange skin actually helps it collect water in this arid land.
Thorny devils exclusively eat ants, up to 2,000 in a meal.
And licking them up one at a time is pretty thirsty work.
Water is a vital resource in the outback.
The thorny devil's scaly skin doesn't sweat and instead is covered with a network of thousands of tiny grooves that work like straws, sucking up moisture from the ground.
The water creeps between the scales, towards the lizard's waiting dry mouth.
This way, the thorny devil can absorb water during rains, catch droplets of dew, and even soak up a drink from damp sand.
A pretty clever way of quenching your thirst in an extreme dry desert.
Now, you might be surprised that the deadly predator at number 8 is a plant.
It's the strange carnivorous pitcher plant.
This odd-looking family of flora are found in extreme locations where the soil is too poor in minerals, too sandy or acidic for most plants to survive.
As they can't get their nutrients from the ground like normal, these plants have developed a deadly strategy.
They catch and devour insects.
Leaves on the plant swell and grow into pods called pitchers which, when they open, are often filled with a special, syrupy liquid produced by the plant.
Like a deadly swimming pool, creatures that fall in will drown and are digested by the juices.
To lure in their prey to a watery grave, the plants are brightly coloured, often sweet-smelling, and ooze nectar from the underside of their lids, all a hit with the locals.
But the edges of the pitcher have slippery, waxy sides, a one-way ticket to trouble.
Ants don't have armbands, so quickly drown in the plant's predatory puddle.
Their bodies decompose into a soup, which is absorbed by the plant, a great source of nutrients that the plant would normally get from the soil.
Energy needed to grow yet more deadly pitchers.
By developing this carnivorous strategy, pitcher plants can thrive in extreme areas where other plants never could, even in mid-air with no soil at all.
Fantastically fatal flora! So, three down, and we've already seen some extreme survivors.
The mountaineering snow leopard, the sucking skin of the thorny devil, and the rather ravenous pitcher plants.
As we count down the list, what could beat these three to number 7? Take a deep breath, because it's an odd-looking, swampy river monster.
It's the lungfish.
These eel-like predators have evolved to be perfectly adapted to life in stagnant, boggy lakes and marshes.
They're well camouflaged, but I'm hoping we'll catch one here in the shallows.
My friend here has managed to net me a lungfish.
Now, most fish would really object to being treated like this, but the clue to why this one is actually doing OK is in the name, lungfish.
It not only has gills here, for breathing in the water, but it also has lungs.
So, that gulping sound you can hear there is it breathing oxygen in the air.
One of the most unusual things about the lungfish is what happens if all this water dries up.
Lungfish have evolved to cope with the most extreme environment for any fish - drought.
In parts of Africa, a lack of rainfall means that swamps and rivers can dry up completely.
This means certain death for most aquatic animals, but the lungfish has a plan.
It burrows down into the mud, using its mouth to excavate a chamber.
Overhead, the mud dries hard, almost like concrete.
But inside its burrow, the lungfish exudes a thick, slimy covering that dries hard around it, forming a waterproof, protective cocoon.
Mummified this way, it can survive for months, or even up to four years, entombed in mud.
Some lungfish have even found themselves incorporated into mud brick houses.
The lungfish stays alive by breathing air and slowing its metabolism to one 60th of its normal rate.
It barely moves, and looks as if it's dead, but it holds out until the rains come.
At the first sign of moisture, the lungfish begins to stir.
Its slime cocoon and muddy burrow soften in the rain.
The fish seems to come back to life and slithers straight for the water.
Due to its slimy shutdown technique and ability to breathe air, the lungfish can survive the most extreme droughts.
A fish out of water? No problem! Next, at 6, are some creatures who survive and thrive in constant darkness.
Good to go, Steve.
We're good to go.
Over.
Caves are dark, damp and generally inhospitable places.
Up in the roof of the cave, with the bats and the birds circling around you, it's kind of like paradise.
And down here is a kind of hell.
But there are some deadly creatures that absolutely love it.
It's home to bats, bugs and weird, scuttling creepy-crawlies.
This, possibly, is one of the nastiest places on the planet.
Caves are extreme environments, as food is hard to come by.
There you go Ooh! That one just ran over my hand! Anything that lives here has to know how to survive or hunt in pitch darkness.
The tiny starlights in the roof of this cave in New Zealand might look lovely, but they are, in fact, the lethal lures of the fungus gnat glow worm.
To try and catch a meal in this harsh cave environment, the fungus gnat larvae employ a clever hunting technique.
They hang sticky threads of mucus-covered silk from the ceiling, like a three-dimensional web.
In the still air of the cave, each gnat larva can manufacture up to 70 separate strands of silk, producing a dense curtain of snares that hang down like beautiful, beaded chandeliers.
Belching beads of gluey mucus onto each strand of silk turns them into exquisite lethal weapons.
Spinning more filaments maximises the chance of catching a meal, as food is scarce.
Each gnat larvae emits a pale blue light from the tip of its abdomen, a chemical beacon that's clearly visible in the surrounding darkness.
It proves irresistible to any insects that stray into the cave.
Mayflies and midges hatching out of underground streams flutter upwards towards the lights, like moths to a flame.
The fungus gnat's snares, invisible from below, are devastatingly efficient.
In an extreme place like this, where there isn't much food to go around, a successful hunting strategy is vital.
Once caught, the fly's struggles only entangle it further.
The larva slowly slimes its way over and begins to winch up its meal, bead by slimy bead.
The prey is then sucked dry and chopped up into tiny pieces to be eaten.
Not a scrap is wasted.
By using silken threads, mouthfuls of mucus and a dazzling tail light, this slimy creature can fish for a living in one of the most extreme cave environments.
We're halfway through the countdown, and so far, we've seen a big cat that lives on the toughest mountain slopes, the desert devil's smart skin, carnivorous pitcher plants, a drought-busting lungfish and some fatally attracting glow worms, all brilliantly adapted to survive extreme conditions.
So, who could beat them on the list? There's a battle for the number 5 slot.
Two foxes are going head to head.
It's the arctic fox versus its sandy cousin, the fennec fox.
First up is the fennec fox, who survives in the extreme heat of North Africa's deserts, where the daytime temperature can reach 43 degrees.
This little fox has some clever adaptations to survive the high temperatures of the Sahara.
It spends much of its day in its burrow.
The freshly dug sand is cool and a great place to hide from the piercing sun.
It also has giant ears.
These are packed full of blood vessels and work like radiators, pumping heat away from the body.
No water in the desert is also no problem for the fennec.
It fills its diet with juicy grubs and succulent snakes even if they are quite a mouthful.
They rarely need to drink water and never sweat.
So, the desert-digging, big-eared, snake-munching fennec fox makes living in extreme deserts look like a walk in the park.
How does his northern cousin match up? In the spring, the arctic fox is a lean, mean killing machine.
It fills its face with seabird chicks and stores food for later, as the arctic winter is going to be tough.
Temperatures plummet to minus 40, 50 or even 60 degrees.
And the arctic fox dresses for the weather, donning a snow suit twice as thick as its spring coat, one of the best insulating furs of any mammal.
The arctic fox is quite literally the polar opposite of the fennec, with small ears, short legs and a fat, rounded body for keeping in the heat.
Its incredible white fur is its weapon against cold, and by curling up into a ball, its tail acts like a duvet over its face.
The fox can keep its body over 50 degrees warmer than the surroundings when snuggled up like this.
It has furry feet, like snowshoes, and special blood vessels in the pads to stop its feet freezing.
Food is hard to come by in winter, but the adaptable fox can even survive on scavenged scraps.
So, both clever canids are pretty extreme, but which one will take the number 5 slot? For me, it has to be the gorgeous arctic fox, surviving freezing temperatures with its oversized overcoat.
A super furry animal! From the polar winter to the desert heat, next at 4.
It's the spoor spider, the master of the dunes.
The sun here in the Namib is utterly scorching.
It can be a bit like wandering around in a sauna, and the sun's rays are soaked up by the surface of the sand, which is unbearably hot.
Mind you, if you dig down just a short way the sand's still cool.
There's lots of animals here that use both these things to their advantage.
They'll bury down beneath the sand to stay cool during the daytime, and they can use the heat on the surface of the sand as a weapon.
Urgh! Our next animal doesn't pose any threat to me.
Wait for us! But the same definitely can't be said for the local ant population.
Ah! We've been looking a lot at tracks and signs of animals, and under here is the hiding place of a very special hunter.
See if we can get it out.
Wow! I think I might have him! There he is.
This is a spoor spider.
He's only very tiny, but he's a very ferocious and really quite clever little hunter.
The spider uses the heat of the sand to kill its ant prey.
Unlike most spiders, the spoor spider spins their web on the ground, carefully weaving together fine grains of sand.
They then flip themselves under this silken mat and, protected from the sun, begin to construct a burrow in the cool layers beneath.
Our thermal camera shows the difference in temperature.
Then Bang! It rockets up its burrow and grabs the ant with one super-strong leg, clamping it down against the baking-hot sand until it actually cooks the ant alive.
It then drags the body back into its burrow to be devoured.
So, by adapting its web to be a sunshield and the perfect ant trap, the spoor spider can take down feisty prey twice its size, using the desert heat to barbecue its meat.
The competition is hotting up, and if that desert hunter got you in a sweat, the animal at number 3 is super cool.
It's the emperor penguin.
Surging out of cold, Antarctic waters, emperor penguins are ready to start their breeding season.
Males have been hunting at sea, and are glossy and fat with fish.
But they need to be, as they're setting off for the start of one of the most extreme trials on Earth.
They trek up to 100 miles on full stomachs, across the frozen ice, to reach their colony.
Hours of painstaking plodding.
Here, they pair up with their mates for the season.
The female hands over the egg, and the tag teams switch places.
It's now Daddy Day Care's sole job to keep the egg safe and warm inside his pouch for two months until it hatches.
And it's about to get a lot colder.
Extremely cold! As the sun drops below the horizon and winter sets in, blizzards drive the temperature down.
In order to survive, the males are forced to hunker down, shuffling together into a group for warmth, taking it in turns to be on the edge, being buffeted by the vicious winds.
They turn their backs to the gales and tuck their beaks down to conserve warmth.
If the huddle breaks, even for a moment, precious heat escapes.
Antarctica is the coldest, windiest place in the world.
The air temperature can drop to minus 60, with winds of up to 120 miles an hour.
By the end of the winter, the male hasn't eaten a thing for four months.
Not only has he survived the coldest, darkest winter on the planet and lost around 45% of his body weight, but he still has the energy to provide the tiny chick with a mouthful of vital food.
And surviving this extreme is all worth it, so the chicks are born early enough in the season that they can grow big and strong before they head out to sea to hunt.
So, what can be more extreme than surviving the coldest, darkest winter on Earth? In at 2 is the largest toothed hunter in the world, the sperm whale.
This giant stalks its prey in the mysterious depths of the oceans.
Big males can be 20 metres long and weigh 45 tonnes.
That's about as heavy as six elephants! And big animals have big appetites.
A sperm whale needs to eat a tonne of food every day.
But the reason why the sperm whale is so extreme is that its dinner lives over a mile down, in the crushing, pitch black of the deep sea.
It's the deepest-diving of all mammals.
Before it submerges, the whale breathes out, a trick to stop its lungs from being damaged under pressure as it dives.
Then, with a flick of its massive tail, it descends at 100 metres a minute.
It can hold its breath for over an hour.
The pressure at a mile down exerts a force the same weight as ten jumbo jets.
But the sperm whale's skeleton is designed to bend, not break.
Its heartbeat slows to a third of its normal speed.
Now, with its body buckled by pressure, no air in its lungs, and its heart barely pumping, it starts to hunt in complete darkness.
The whale uses echolocation to hunt for squid underwater.
Like a submarine, he sends out clicks and calls that bounce back to build up a picture of its surroundings.
And, once it's had its fill, the whale surges to the surface to breathe.
By being equipped to go where other mammals can't, the sperm whale gets a rich fishing ground all to itself.
Now it's time for a refreshing reminder of the extreme predators we've seen so far in our 10 to 2 countdown.
The rock-climbing snow leopard makes crumbly cliffs look cosy at 10.
Knobbly 9 is the thirsty thorny devil.
Drowning out the competition at 8 are the pitcher plants.
Slippery 7 is the slime-covered lungfish.
The fatal fairy lights of the glow worm are at 6.
Staying alive at 5 is the all-white arctic fox.
Our ant-snatching spoor spider is at 4.
Weathering the world's worst winter at 3 is the emperor penguin.
And diving in at 2 is the phenomenal sperm whale.
So, what on earth is going to top all of that to the number 1 in my Deadly Top 10 extreme? It's the wood frog, and trust me, they have the ultimate survival strategy.
The wood frog lives in North America, where the winters are harsh.
Its range even stretches up into Alaska, further north than any other frog.
Cold-blooded creatures struggle to survive in cold weather, so this frog takes extreme survival to another level.
When the winter temperature starts to drop, the wood frog takes refuge underground.
As it gets colder still, the icy frost penetrates the soil, and being cold-blooded, our toad-in-the-hole starts to freeze.
The frog uses some clever chemistry to protect itself from spiky, dagger-like ice crystals damaging its insides.
It packs its cells with sugars, which work like antifreeze.
Using glucose is a pretty sweet trick as it prevents the frog's cells from being destroyed by ice crystals, which form between the cells and in the bloodstream instead.
With no breathing, no movement and even no heartbeat, the frog should be dead.
But the sugars stored in its body provide just enough energy to keep the cells alive through the deepest part of the winter.
Frozen in time, this incredible frog can survive as an ice pop, with 65% of its body frozen solid for up to four weeks.
But even with all its vital functions on hold, there is life in the old frog yet! When spring arrives and the temperatures start to rise, the frog's body begins to thaw.
The defrosted heart muscle is kick-started back into action, and blood starts pumping around the body.
The once-frozen frog is almost completely back to normal within 24 hours and hops to it, taking advantage of being the only frog in town! So, that's my Deadly Top 10 extreme done! Don't forget to join me next time for more Deadly Top 10s.
Who's going to be the next deadly number 1?