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00:00Life has been evolving on planet Earth for three and a half billion years.
00:21Natural selection has shaped creatures to survive in nearly every habitat on the planet.
00:30And in the last few decades, humans have found that solutions to many of our technology problems are just waiting to be discovered in the vast library of life.
00:51In this program, we see how animals survive extreme conditions and how this helps us.
00:57We'll see how a woodpecker can show us how to cushion a fall from space.
01:06Or how understanding birds on the extreme upper limit of size inspires the design of a submarine.
01:13And how giraffes can help jet pilots survive extreme G-forces.
01:23Animals that survive in the extreme cold have different ways of enduring such bitter temperatures.
01:41One is to become very big.
01:45Another, to have very thick fur.
01:47Fur insulates against the cold, but creates a problem when cold climate animals like huskies start to do what they do best, to run.
01:59When they run, they get hot.
02:00They get hot.
02:01They could overheat.
02:02And the problem is worse if they run in a warm climate.
02:03They get hot.
02:04They get hot.
02:05They get hot.
02:06They get hot.
02:07They get hot.
02:08They get hot.
02:09They could overheat.
02:10And the problem is worse if they run in a warm climate.
02:16So, how does such a furry animal get rid of excess heat?
02:22And the problem is worse if they run in a warm climate.
02:29So, how does such a furry animal get rid of excess heat?
02:36It has several ways of doing it, which can be seen when we look at the dogs with a thermal camera.
02:54The white areas are the hottest.
02:56And these are the parts dumping body heat, trying to cool the animal down.
03:05Like all dogs, huskies pant to cool down, releasing heat from the open mouth and tongue.
03:12But there's another way to get rid of heat, from one of the few parts of the body not covered in fur, the soles of the paws.
03:27Here, the blood supply comes very close to the surface of the skin.
03:40The paws radiate heat, and as they do, cool down the dog's whole blood supply.
03:46Professor Dennis Grahn of the University of Stanford studies how animals dissipate heat.
03:55While it seems to be a very small surface area, it's the amount of blood and heat being delivered to the surface that counts.
04:05A tremendously high volume of blood going through these radiator structures.
04:11This is the only place the heat can get out of the body.
04:14This could help cool down someone who's overheating.
04:17But the blood needs to be close to the surface for it to lose heat.
04:21So the question then came, how do we open up blood flow in someone that doesn't want it opened up?
04:28They created a blood sucking device that has a slight vacuum to bring the capillaries nearer to the skin surface and open them up.
04:38They're then cool to chill the blood passing through the capillaries.
04:43To test it out, we need someone who's overheating.
04:47Playing American football is exhausting.
04:58And hot.
05:00The thermal camera shows the player's temperature.
05:03White, bright colors are hot, and red and blue are cooler.
05:08And for this experiment, we'll make the players even hotter.
05:23Exhausted and overheated, the players need time to recover.
05:27But one of them will be using the cooling device.
05:31Once the hand is inside, the vacuum will pull the blood to the surface of the skin.
05:38And we can see how the device helps the player recover.
05:42What we've found is that temperature seems to be a primary limiting factor for human performance.
05:53When we apply cooling, we see that their performance capacity increases dramatically.
06:02The player with the glove is already darker and cooler.
06:06As his temperature drops, he recovers quickly.
06:14Then he's ready to go again while his teammate is still exhausted.
06:20There's a lot of opportunities for healthy people to improve their performance in either hot or cold climates by utilizing these radiators structures.
06:36There's a lot of medical conditions that individuals could really benefit from this type of amplification of your natural cooling systems.
06:49We're taking advantage of this amazingly elegant mammalian physiological adaptations that enables animals to live anywhere on the planet in virtually unrestricted conditions.
07:11Wherever they live, animals and plants can face extreme conditions.
07:16The tropics don't seem too much of a challenge.
07:20Everything from birds to bugs thrives in the world's tropical rainforests.
07:28But creatures living here still have their own problems.
07:32Staying dry.
07:34Rainforests, as their name suggests, are extremely wet.
07:46Rainforests, as their name suggests, are extremely wet.
07:50In some forests, over 10 meters of rain drench the forest's animals and plants every year.
08:08Staying dry is a matter of life and death.
08:12Small creatures risk drowning.
08:16And a wet leaf could be quickly covered by growths of algae or fungi in this hot, wet climate.
08:22Yet water just rolls off the leaves of most plants.
08:40They're covered in layers of waxes, making the leaf water repellent or hydrophobic.
08:56In the rainforest, it's not just plants that must stay dry.
09:00A butterfly with soaking wet wings would be grounded.
09:04But again, water just rolls off them.
09:08The scales on the wings have a structure that makes them water repellent.
09:18The spider doesn't have scales.
09:20It has a layer of hair.
09:22But a dense covering of hairs can be just as water repellent.
09:40This spider can swim.
09:42Its water repellent hairs trap a layer of air around its body.
09:46Its own personal buoyancy vest.
09:50And it emerges completely dry.
09:56Hairs, scales, leaves all work in a similar way.
10:02But the supreme example of a water repellent leaf.
10:06A lotus leaf.
10:08It's so unwettable it's called super hydrophobic.
10:13It's so unwettable it's called super hydrophobic.
10:15It's so unwettable it's called super hydrophobic.
10:17It's so unwettable it's called super hydrophobic.
10:19It's so unwettable it's called super hydrophobic.
10:23being super hydrophobic has another advantage as the water droplets roll off they collect dirt and
10:50fungal spores so every time it rains the leaf is thoroughly cleansed the lotus doesn't just rely
11:02on wax at the microscopic level it has tiny precisely arranged bumps covering its surface
11:10these are tipped with water repellent waxes which stop the water droplets from reaching the leaf
11:18surface there's so little contact between the leaf and the water that water just rolls off we can copy
11:31the lotus structure with a water repellent service that like the lotus leaf keeps itself clean
11:37but one plant here is different it uses layers of wax to kill the pitcher plant
11:52this pitcher has a layer of wax around the rim to create a deadly trap the rim is so slippery
12:02that ants can't get a grip some lose their footing and tumble into the water inside the pitcher
12:24drowning in the liquid the ant is slowly digested releasing nutrients that are absorbed by the
12:31plant but how does the pitcher's slip zone work the wax crystals form a system of overlapping downward
12:41pointing tiles with nowhere for an insect to grip this is even more effective when it rains the spaces
12:53between the tiles hold a thin layer of water which makes the rim even more slippery in Harvard University
13:00a team is developing this idea to make an artificial version of the pitcher plant surface
13:07they call their material slips so how does this pitcher plant inspired material compare to services based on
13:18the lotus leaf one sleeve of the lab coat is made from a lotus style material the other from slips and the rest of
13:29the coat of the coat is normal fabric
13:31not the most scientific test in the world but the results are clear
13:51the lotus sleeve looks okay but the slip sleeve is as good as new
13:59so let's test a bigger range of substances the artificial lotus surface is on the left the slips on the right
14:13for most of these substances slips is more repellent than the lotus based surface
14:22and the ultimate test spray paint it simply rolls off the slips material
14:43inspired by nature artificial waterproof surfaces are as effective as those made by nature
14:54just as an experiment to show how good they can be we can even treat absorbent surfaces like newspaper
15:06and the water just rolls off
15:13both natural and man-made services shed every last drop of water
15:15both natural and man-made services shed every last drop of water
15:20but super hydrophobic surfaces can do more than just make things waterproof for fun
15:27this drop of water lands on a metal surface cooled to minus 40 degrees
15:32cooled to minus 40 degrees Celsius
15:34both natural and man-made services shed every last drop of water
15:38but super hydrophobic surfaces can do more than just make things waterproof for fun
15:42this drop of water lands on a metal surface cooled to minus 40 degrees Celsius
15:57it sticks there and freezes instantly as drops accumulate a layer of ice builds up
16:03but on a slip surface the water just rolls off before it can freeze
16:20in freezing weather ice builds up on plane wings so the wings must be de-iced with antifreeze
16:26this is expensive causes frustrating delays and puts the airport
16:33but if we could coat planes wings with slips the water would simply roll off no matter how cold it gets
16:41the very latest research is showing that nothing seems to stick to slips
16:48it's omniphobic and that includes bacteria
16:53if bacteria can't stick they can't multiply a surface that completely rejects bacteria
17:06has enormous potential for medical science for reducing infection and reducing costs of deep cleaning
17:13there are extremes of heat and cold wet and dry but some animals also have to cope with extremes of size
17:36there's an upper limit to the size and weight of a flying bird
17:40the bigger it is the more muscle it needs to fly
17:51but beyond a certain size a bird can't fit enough muscle into its body to generate the power needed
17:57this is the limit a large swan it needs a long takeoff run just to get enough air flow over its wings to get airborne
18:12another big bird with a similar wingspan has a different problem
18:26the vulture
18:29cape vultures are the heaviest vultures in Africa and they also find it hard to take off
18:40and their lifestyle adds to the problem
18:47vultures gorge themselves at one sitting they can increase their body weight by up to ten percent at a time
18:53being this full of food takeoff is hard work
18:59but once in flight vultures are very efficient
19:12they move through the air with very little flapping
19:14and the takeoff problem can be solved by roosting on a cliff face
19:29simply drop into the air
19:33and soar
19:42unlike the swans who have to flap to fly
19:45vultures keep their wings fixed in place and soar
19:49carried by rising thermals of warm air
19:52vultures use free energy from rising air to cheat the system
19:55they don't need muscle power to stay aloft for hours
20:01using minimal energy they can reach heights of three kilometers and travel hundreds of kilometers in their search for carrion
20:11this efficiency comes from the shape of their wings broad and square giving a lot of lift relative to their weight
20:24and we can use a similar idea when designing energy efficient craft
20:30a complete contrast from the vultures of south africa
20:35Hawaii
20:37yet the design of this submarine uses the same principle as vultures wings
20:43pilot
20:47John Joe Lewis is about to take super aviator for a dive
20:52super aviator is very different from other submarines
20:59it steers with tail rudders like a plane and like a plane it has wings
21:14I'll write that about two points time at three zero zero
21:24these wings are locked in place like the vultures wings
21:27but they're upside down
21:30as the sub moves through the water the wings draw it down rather than up
21:34the sub is flying through the water
21:42looks like we're just going over the edge of this reef
21:49like the vultures the sub is very energy efficient gliding through the water
21:58and being more maneuverable and using less energy than a conventional sub allows the pilot to explore further
22:04It's really possible to do more sightseeing in a sub like this because with the traditional bubble sub you sort of have to decide where you want to go
22:11once your ship board and then steam over there drop the sub overboard and then the sub can putter around in various directions
22:18but if you wanted to examine something that was say 5,000 meters away you'd really want to bring the sub back up to the surface hoist it on board move the ship and drop it again
22:25whereas we can be very spontaneous follow things that look interesting follow a reef that looks promising and really just go where we feel like it
22:33and really just go where we feel like it
23:03One, three, five feet commencing breach
23:10Fifty feet
23:14Twenty feet
23:20Whoa
23:26Very nice
23:28Sub on the surface, sub on the surface
23:30If we want to get somewhere quickly we need to go faster to accelerate
23:53But the human body can't endure too much acceleration
24:00Yet other creatures in the natural world can withstand such extreme acceleration it would kill a human
24:21When a creature speeds up it's accelerating and when it's accelerating it feels a force on its body
24:28It feels heavier
24:30It feels heavier
24:35A measure of how much heavier it feels is called a G-force
24:38Twice as heavy is called 2G
24:42But there's another way to experience these forces
24:54A rapid change of direction turning a corner
24:58Hummingbirds make the tightest fastest turns in flight
25:03The tighter the turn the greater the greater the G-force
25:06The tighter the turn the greater the G-force
25:07And these little birds experience 9G on some of their turns
25:10Likewise pilots in a tight turn feel G-force is acting on them
25:25But unlike hummingbirds can only tolerate up to 5G without help
25:30Under high G blood is forced from the head into the lower parts of the body
25:37And as the brain is deprived of blood the pilot can black out
25:49One way to reduce this effect is to wear a G-suit
25:52A G-suit applies pressure to the body to counteract the G-force effects
25:59But it's not perfect
26:01To survive high G a pilot still needs training in specialised breathing techniques
26:09And beyond 9G the pilot can still black out
26:13We need a better way to make a G-suit
26:17And to find out how we turn to a familiar animal
26:24The giraffe
26:28With their heads several metres above their hearts
26:31Their hearts have to pump extremely hard to get blood to the brain
26:47Because the heart pumps so hard the lower legs feel higher blood pressure
26:54So they have the equivalent of a G-suit around their legs
26:57Of tight connective tissue under the skin
27:02But what happens when they bend down to drink?
27:08This is a model giraffe to show what should happen to the blood pressure
27:12When a giraffe lowers its head to the water
27:18A water pump acts as the heart
27:20Generating the pressure needed for blood to reach the head
27:23The gauge shows blood pressure for human, giraffe and danger
27:43What happens when it stoops down to drink?
27:45The heart is still pumping but against less resistance
28:03And the pressure in the head goes up
28:05The head goes up
28:28But a real giraffe's head doesn't explode when it takes a drink
28:31How does the giraffe survive such extremes of blood pressure?
28:38And can that help us?
28:43We need to know how the giraffe manages its blood pressure when it moves its head
28:49There's one way to find out
28:50There's one way to find out
28:59In Johannesburg, a team of experts is going to try something never done before
29:08A combination of cutting-edge technology and veterinary science
29:12First, anaesthetize a giraffe
29:23As the giraffe slowly loses consciousness, they support its neck to keep its windpipe open
29:34Such research on giraffes is helping us understand more about high blood pressure
29:52A serious medical condition in humans
30:06And it also helps to understand how to compensate for high G-forces
30:11Keeping an animal this big anaesthetized for too long is risky
30:14And cardiac expert Tobias Wang is restless
30:18We are struggling against time now
30:20We have to get this sorted within 45-60 minutes
30:24But I'm optimistic right now at least
30:26It's going really well, it's going really well
30:28These highly skilled surgeons are implanting sensors that will read the blood pressure changes in the giraffe's neck
30:32And transmit the results to the scientists by a radio link
30:45We now have thoracic cardiac surgeons that are going to make the implants
30:49We have the engineer who has designed the equipment standing over here
30:53And he is like no one in the world
30:54So it is the A-team we have collected here
30:59It's basically the best people that one can imagine
31:02So if we can't do it, I don't think anybody can
31:08One sensor goes near the heart
31:14And the other in the top of the neck
31:19So the changes in blood pressure can be monitored
31:21The team is waiting for the giraffe to recover
31:46Yes, that's a fantastic relief, it's unbelievable
32:00It just got up, it goes perfect, everything went perfect
32:03So, come on
32:05Unbelievable
32:07Unbelievable
32:08Tomorrow he'll be fine
32:10And we've got to get on the days we want
32:12Fantastic, fantastic
32:13Phew
32:16Phew
32:32The giraffe, completely recovered, is returned to the reserve
32:37And is now transmitting on Wi-Fi
32:43Over the following months
32:51The results show that the way the giraffe's body adapts to changes in blood pressure
32:57Is even more complex than we first thought
33:00The giraffe employs a number of features
33:04Expanding veins in the neck
33:06Constricting vessels in the brain
33:08And a reduced output from the heart
33:10And these changes happen automatically and almost instantaneously
33:21A team of Swiss engineers is applying what we're learning about giraffes to the design of a new G-suit
33:29The G-Raffe suit
33:31In Germany, a powerful centrifuge is used to train and test Europe's top fighter pilots
33:39But Ralph is not a pilot
33:45He's a civilian volunteer
33:47And he's testing a new prototype of the giraffe suit
33:50A fighter pilot can only tolerate 9G with a lot of training as well as a standard G-suit
34:00Ralph doesn't have any training, but he does have the new suit
34:05Like the blood vessels in the giraffe's neck
34:09The suit has a system of valves that responds automatically and quickly
34:18By moving air around the suit, the valves maintain pressure on the body as needed
34:24So the blood doesn't pool in the body and drain from the head causing blackout
34:29Ralph will test the suit at increasing G-forces
34:33Ralph will test the suit at increasing G-forces
34:41Ralph, are you ready now?
34:43Yeah, I'm ready
34:45Three, two, one, go
34:48Go
34:58The centrifuge is normally used as a flight simulator imitating the feel of a jet fighter
35:05Ralph tries out tasks a trainee pilot would do
35:10But now it's time to really test the new suit
35:14Are you ready for the last session?
35:15Up to eight or to nine Gs?
35:18Yeah, we can start with this
35:19I'm ready
35:28In the old suit, most trained pilots would be struggling by now
35:33But the new suit is maintaining the pressure on his body
35:36And stopping the blood draining from his head
35:39Ralph is not only conscious, he can even try a complex task
35:46He completes a puzzle, that most of us would find hard anyway, at 9 G
35:53And it's all down to giraffe technology
35:57Well done
35:59Good
36:00Good
36:01Good
36:12Nature has evolved ways to cope with manoeuvres at high speed
36:16But with extreme speed comes the danger of collision
36:19Impact at high speed is just as dangerous as extreme acceleration
36:37But once again nature has found ways to cope
36:41And even turn extreme impact into a weapon
36:44The peregrine, a predator, and it uses impact to kill
36:59The peregrine dives onto its prey
37:02The faster it goes, the more lethal the impact
37:05The faster it goes, the more lethal the impact
37:08To show just how fast a peregrine can dive, bird handler Lloyd Buck
37:09its prey the faster it goes the more lethal the impact to show just how fast
37:26a peregrine can dive bird handler Lloyd Buck flies his peregrine willow the
37:35capable of speeds up to and over 150 miles per hour would I in fact has been clocked at 114 miles per
37:44hour good lad the peregrine takes its prey in midair killing it with a blow
37:59so how does the collision leave the victim dead and the peregrine unhurt
38:06when the peregrine strikes it hits with its feet and claws
38:18the peregrine skeleton tendons and muscles absorb this shock the bird has very strong leg and hip
38:27bones and loose hip joints to absorb the energy of the impact
38:34by killing with its feet there's no need for this bird to protect its head
38:39but what if the head itself is the weapon
38:49big horn sheep the males have to prove themselves
38:54and they do it with brute force at a closing speed of 10 meters per second
39:02simple but effective bang heads until one of them gives up
39:06but the males need protection from such massive blows
39:15the male skull has a double layer of bone honeycombed with struts to protect the brain
39:21and strong tendons in the neck also absorb the impact
39:28head-banging males need head protection the sheep has a built-in helmet
39:33but humans have to design their own
39:43the outer casing is tough but slightly flexible
39:46while inside that a layer of elastic padding cushions some of the shock
39:51helmet design is always being refined and improved
40:12big horn sheep seem the obvious place to look for inspiration for better shock protection
40:17obvious but wrong meet the most famous headbanger of all the woodpecker
40:47the woodpecker eats grubs that live under the bark of trees
40:54and don't want to come out
40:58so the woodpecker has to drill into the wood to get at them
41:04it's using its beak and head as a chisel so how does it protect its brain
41:09the woodpecker's head experiences 1200g on every impact and they happen 20 times a second far greater
41:22shocks than the big horn sheep
41:26researchers are just beginning to understand why the woodpecker doesn't get a headache
41:30it's because of the unique structure of its head and skull
41:37the beak is very hard but elastic and the beak is disconnected from the skull
41:43there's a springy bone between them to dampen the shock
41:47the skull is rigid but then there's a layer of spongy bone between the skull and the brain to further dampen the shock
41:54finally a thin layer of viscous fluid reduces the transmission of the impact to the brain
42:07so how can we use this understanding to design new shockproof containers
42:12to test this idea we've come to the nevada desert
42:32we're going to do an experiment never attempted before
42:42using our understanding of how the woodpecker skull protects its brain
42:47we've built a canister based on its design
42:50and we're going to drop it from a very great height
42:55from the edge of space
42:56to carry the canister this high we'll use a weather balloon
43:11engineer john powell or jp has prepared the canister it doesn't look too much like a woodpecker skull
43:19but it really is we have the outer layer here and this is a carbon fiber outer layer
43:25the idea is this is the layer that's allowed to flex
43:29now this inner cylinder is actually fiberglass and it's very rigid and brittle so the load is allowed
43:36to flex here but not allowed to flex into the interior
43:43in the same way the woodpecker brain is surrounded by spongy bone jp uses tiny polystyrene balls to pack
43:50the interior the idea is that you provide a disconnect there's no impact path from the outside impact
43:56which will hit pretty hard dropping it from the edge of space into the center so there's a series of
44:01disconnects in there you can tell them 15 minutes to completion
44:06the next question is what will the canister carry
44:19it's just a regular hardware store bulb because if you drop it off the table it's going to break
44:24the real trick is if i drop it from up there and have it not break that's kind of the first test
44:34if the fragile bulb survives the second test the real um challenge is the thin wire filament in there
44:45to see if that does not break the bulb is packed into the canister using microspheres
44:51so i'm trying to get them literally everywhere
44:57now the real trick is can i get this in without spilling the beads
45:08there we are
45:14the canister is now attached to an arm which is fixed to the flight vehicle
45:21the platform also carries cameras gps systems and the release mechanism
45:29all this equipment allows jp and the team to monitor the ascent and control the release
45:39the balloon is ready for takeoff
45:51the balloon and canister rise quickly it'll only take 90 minutes for the balloon to reach the edge of space
46:21as the balloon climbs the atmosphere gets thinner and the helium inside the balloon expands
46:35the team follow its progress
46:39how are we doing everything's looking really good
46:41we've got a boat we've got the vehicle at just over 30 000 feet climb rate of just over 1200 feet per minute
46:50down range distance is 16.9 miles
46:54looks good
46:58okay that's north lake
47:00well shouldn't we be right there
47:04yeah
47:04the balloon is now of a twice as high as a cruising jetliner
47:23and at 88 000 feet the team send the radio signal to release the canister
47:29the structure carrying the canister starts to spin as it falls
47:51there's little air resistance up here to slow down its fall
47:55it accelerates quickly and is soon spinning at three revolutions a second as it drops
48:12so
48:14now all the team has to do is find it somewhere in the vast desert
48:36last fix we got was about 12 000 feet which is about 7 000 feet above the ground where it landed
48:42although since we don't have the exact fix it could be within two miles of one direction or another
48:49the canister is on the ground but the balloon is still climbing
48:54at 90 000 feet the atmosphere is so thin the balloon just keeps expanding and stretching
49:12the flight vehicle and shredded balloon fall back to the desert
49:28the team needs to find both the canister and the flight vehicle
49:32they're somewhere in these hills but they haven't yet got an accurate fit
49:52next day the team resumes the search
49:54this is why they came to the desert they didn't want the falling canister to damage anything
50:03oh here it is it hit right here
50:10the container looks completely undamaged
50:13which is not the case for its carrier the flight vehicle
50:17flight vehicle 67 this is the unit that dropped the hammer we're recovering the vehicle
50:23it came down on a solid rock phase
50:32bam and so we don't really know what what we're gonna find we may be just looking at powder inside powder here
50:40okay i'm almost afraid to look
50:54well the system looks pretty all intact
50:59oh there we go
50:59there we have a bulb
51:09oh excellent
51:13everything looks good it looks like it's intact
51:17um but the proof will be in the lighting
51:29that would have spiked you know well over a thousand probably probably close to uh 2000 plus g's
51:49so it got a pretty extreme ride for a light bulb
51:53this technology has incredible potential from helmets to flight recorders shock absorbers will never be the same again
52:14the way some creatures survive extreme conditions can give us new ways to push the limits of our technology
52:21we can find new ways to take us beyond our normal endurance
52:25hidden in the vast library of life
52:37in the next program we see how the ongoing evolutionary arms race reveals new exciting designs
52:44powers that we can adapt to advance our own technology
52:58you
53:03you