0:00:04 > 0:00:08The sky is one of the most challenging places to live.
0:00:10 > 0:00:14But all across the world, extraordinary animals do
0:00:14 > 0:00:16something we can only dream of...
0:00:18 > 0:00:20..take to the air.
0:00:24 > 0:00:26Some spend their whole lives up here.
0:00:29 > 0:00:33Others only visit for a moment.
0:00:35 > 0:00:39We'll discover how many incredible animals thrive in the sky...
0:00:43 > 0:00:46..and what clever tricks they use to get airborne.
0:00:48 > 0:00:51With the help of some specially trained animals,
0:00:51 > 0:00:56the latest technology and special effects techniques,
0:00:56 > 0:00:59we'll reveal brand-new discoveries
0:00:59 > 0:01:02that explain how animals take to the skies.
0:01:05 > 0:01:07This is Life In The Air.
0:01:20 > 0:01:23Right now, there are billions of creatures
0:01:23 > 0:01:26living in the three miles of air above our heads...
0:01:26 > 0:01:28without us evening knowing they're up here.
0:01:30 > 0:01:32They've overcome gravity,
0:01:32 > 0:01:36they've mastered flight and now they live their lives up here,
0:01:36 > 0:01:40making the most of the opportunities the skies have to offer.
0:01:41 > 0:01:44There are over a thousand species of mammal
0:01:44 > 0:01:47and over tens of thousands of species of birds up here.
0:01:50 > 0:01:54The biggest numbers are the smallest players.
0:01:54 > 0:01:58And the closer you look, the more of them you see.
0:01:58 > 0:02:02Insects, trillions of them,
0:02:02 > 0:02:08so many that 98% of everything that flies is an insect,
0:02:08 > 0:02:10and most of them don't even have names.
0:02:12 > 0:02:17The air above us is more crowded and more dangerous than you might think.
0:02:21 > 0:02:23Predators are everywhere.
0:02:25 > 0:02:28At every level, the skies are teeming with life.
0:02:30 > 0:02:32There are thousands of creatures using
0:02:32 > 0:02:34the skies as super-highways,
0:02:34 > 0:02:36travelling huge distances
0:02:36 > 0:02:38to find food or to migrate.
0:02:43 > 0:02:45Butterflies.
0:02:45 > 0:02:46Even ladybirds.
0:02:54 > 0:02:57Over a kilometre above our heads there are moths
0:02:57 > 0:02:59speeding by at 80 kilometres an hour.
0:03:06 > 0:03:09But what happens when so many lives collide?
0:03:16 > 0:03:18How do animals compete with each other up here?
0:03:23 > 0:03:25How do they win a mate?
0:03:29 > 0:03:30How do they find food?
0:03:32 > 0:03:35How do they hunt, and avoid being hunted?
0:03:36 > 0:03:40Up here, animals are pushed to the limits of what's possible.
0:03:45 > 0:03:48Welcome to another world,
0:03:48 > 0:03:50a world of intense competition,
0:03:50 > 0:03:54of extreme lives in crowded skies.
0:04:09 > 0:04:13The coast of South Africa is home to one of the most extreme
0:04:13 > 0:04:15fliers in the natural world.
0:04:16 > 0:04:20The Cape gannet has a unique way of beating the competition
0:04:20 > 0:04:22when it comes to finding food.
0:04:33 > 0:04:35The size of this island breeding colony
0:04:35 > 0:04:39shows the richness of the seas around them,
0:04:39 > 0:04:43enough to supply the tonnes of fish caught by these birds every day.
0:04:47 > 0:04:50But it's how they catch fish that's so remarkable.
0:04:51 > 0:04:54Here, the competition from other sea birds is intense.
0:04:55 > 0:04:59Most can only catch fish when they swim close to the surface.
0:05:03 > 0:05:06But there are richer pickings deeper down.
0:05:07 > 0:05:09And that's what the gannets are after.
0:05:12 > 0:05:15It requires an extreme form of flying that would kill most
0:05:15 > 0:05:16other creatures.
0:05:20 > 0:05:22Several kilometres from the gannets' colony,
0:05:22 > 0:05:25a vast shoal of sardines is massing.
0:05:28 > 0:05:31And 20,000 gannets are heading out after them.
0:05:33 > 0:05:37But most of the sardines are several metres below the surface,
0:05:37 > 0:05:40completely out of reach for the other sea birds.
0:05:40 > 0:05:42So the gannets prepare to perform
0:05:42 > 0:05:46one of the most dangerous flying stunts in the animal kingdom.
0:05:52 > 0:05:55Climbing 30 metres above the surface,
0:05:55 > 0:05:58they drop from the sky using gravity to accelerate...
0:06:12 > 0:06:15Hitting the water at 100 kilometres an hour.
0:06:15 > 0:06:18with the same force as a bullet fired from a handgun.
0:06:24 > 0:06:26The impact should kill them.
0:06:27 > 0:06:29At that speed, it's like hitting concrete.
0:06:37 > 0:06:40So how can they possibly survive?
0:06:51 > 0:06:55Less than a second before contact, they tuck in their wings and change
0:06:55 > 0:06:59their shape, streamlining their body to slice through the water.
0:07:02 > 0:07:05The gannets have air-filled pockets under the skin in their necks
0:07:05 > 0:07:08and chests, thought to act like airbags to help
0:07:08 > 0:07:11cushion their bodies from the impact of the water's surface.
0:07:15 > 0:07:19But their technique must be precise.
0:07:19 > 0:07:22If their shape isn't perfectly streamlined,
0:07:22 > 0:07:24the impact of hitting the water would crush them.
0:07:29 > 0:07:32The dive propels them down to where the fish are schooling
0:07:32 > 0:07:34but they still have to catch them.
0:07:34 > 0:07:39Exactly how they do that depends on a critical decision each bird
0:07:39 > 0:07:41made the second before it dived.
0:07:52 > 0:07:55In mid-air, the gannet has two choices -
0:07:55 > 0:07:58to dive shallow or to dive deep.
0:08:01 > 0:08:04A quick, shallow dive allows it to hit the water fast
0:08:04 > 0:08:07and instantly snatch any fish near the surface.
0:08:09 > 0:08:11But once under attack,
0:08:11 > 0:08:15the sardines escape downwards, and the gannets must up their game.
0:08:21 > 0:08:23..diving almost vertically to give them
0:08:23 > 0:08:27the speed to reach 10m underwater in a few seconds.
0:08:49 > 0:08:52Their extreme dive has taken them to an alien world,
0:08:52 > 0:08:56far away from the competition from the other sea birds.
0:08:57 > 0:09:01A world where wings become fins, feet become paddles...
0:09:03 > 0:09:06Even their eyes change shape so that they can see underwater,
0:09:06 > 0:09:08and special eyelids act like goggles.
0:09:14 > 0:09:18They are the only birds down here, and they reap the reward.
0:09:32 > 0:09:35Running out of breath, they return to their sky world
0:09:35 > 0:09:38using the air trapped in their feathers
0:09:38 > 0:09:40to carry them back to the surface.
0:09:45 > 0:09:49Risking death to dive deep allows gannets to escape the competition
0:09:49 > 0:09:51and find food for their families.
0:09:53 > 0:09:55But using extreme flying to catch
0:09:55 > 0:09:58food is not just a survival trick for gannets.
0:10:00 > 0:10:02There's plenty of food out there
0:10:02 > 0:10:05for the animals who can fly well enough to catch it.
0:10:08 > 0:10:12An African skimmer goes fishing too, flying with such precision that the
0:10:12 > 0:10:16lower part of its beak can feel for fish just below the surface.
0:10:16 > 0:10:20If it snaps shut, it's caught a fish.
0:10:25 > 0:10:29There's a fishing bat that expertly deploys its enormous clawed
0:10:29 > 0:10:31talons as trawling fish hooks.
0:10:36 > 0:10:40But bats had better watch out or they might become food themselves.
0:10:42 > 0:10:43Falcons use quick reactions
0:10:43 > 0:10:47and extreme control to catch fast flying bats in mid-air.
0:11:04 > 0:11:08Food is not the only thing animals in the skies compete for.
0:11:08 > 0:11:11When it comes to finding a mate, there are some creatures
0:11:11 > 0:11:13who've taken this to a record-breaking extreme.
0:11:16 > 0:11:18Meet the Anna's hummingbird.
0:11:28 > 0:11:30One of California's finest.
0:11:30 > 0:11:32He's no bigger than a ping-pong ball,
0:11:32 > 0:11:35no heavier than a 20-pence coin,
0:11:35 > 0:11:37but he's a record-breaking flying machine.
0:11:43 > 0:11:47His wings pump at 2,500 times a minute.
0:11:48 > 0:11:52His heart beats at 1,200 times a minute
0:11:52 > 0:11:54and he can hover for well over an hour.
0:12:01 > 0:12:03He needs to mate,
0:12:03 > 0:12:06but he has to prove that he's fitter than the rest.
0:12:08 > 0:12:11He has a problem.
0:12:11 > 0:12:14There's another male vying for the female's attention,
0:12:14 > 0:12:17and he's a record-breaking flying machine too.
0:12:22 > 0:12:24Let the competition commence.
0:12:41 > 0:12:43Aggression drives the intruder away.
0:12:46 > 0:12:49But that in itself doesn't impress her enough.
0:12:49 > 0:12:54Now he's going to have to pull off the flying stunt of his life.
0:12:54 > 0:12:57First, he woos her to his performance arena with a song.
0:12:57 > 0:12:59IT CHIRPS
0:13:07 > 0:13:09Now he's got her attention,
0:13:09 > 0:13:12the stage is set for this tiny bird to perform
0:13:12 > 0:13:16the fastest courtship display ever seen in the animal world.
0:13:21 > 0:13:23He climbs 30m above her...
0:13:32 > 0:13:36Then for the grand finale, he dives straight at the ground.
0:13:46 > 0:13:50That was it, over in a few hundredths of a second.
0:13:52 > 0:13:53And again.
0:13:55 > 0:13:59To see what he's doing, we need to slow things down.
0:13:59 > 0:14:01This is much more than just high-speed flying.
0:14:09 > 0:14:13By folding his wings in tightly, he mimics a missile,
0:14:13 > 0:14:17travelling 20m and 400 times his body length every second.
0:14:24 > 0:14:27At the last moment, he pulls up sharply,
0:14:27 > 0:14:30pulling more Gs than a jet fighter pilot.
0:14:45 > 0:14:48But it's not just the speed, the height or
0:14:48 > 0:14:52the angle of his flight, it's all about serenading on the wing.
0:14:54 > 0:14:58His tail is singing a sweet song with jet-fighter force.
0:15:06 > 0:15:09The air screaming through his spread-out tail feathers makes them
0:15:09 > 0:15:12vibrate in a very special way.
0:15:12 > 0:15:16BUZZING
0:15:16 > 0:15:19Slowed down, this is the sound they make.
0:15:21 > 0:15:24BUZZING
0:15:26 > 0:15:30BUZZING
0:15:30 > 0:15:32It's far louder than any of his singing.
0:15:32 > 0:15:36And the faster he dives, the better it sounds.
0:15:36 > 0:15:40BUZZING
0:15:43 > 0:15:45Who'd have thought that a sound like this...
0:15:45 > 0:15:46BRIEF CHIRP
0:15:46 > 0:15:48..or this... BRIEF CHIRP
0:15:48 > 0:15:51..would make all the difference and see off the competition?
0:15:51 > 0:15:54To her, it proves he's fit.
0:15:56 > 0:16:00This bird boy-racer has won himself a mate by pushing
0:16:00 > 0:16:04himself to the limit and proving he's got what it takes.
0:16:05 > 0:16:08But he's not the only one who knows that a little showing off
0:16:08 > 0:16:10can go a long way.
0:16:14 > 0:16:17Aerial displays are a serious business.
0:16:17 > 0:16:21The greater the effort, the more lasting the impression.
0:16:22 > 0:16:25Meet the male spatuletail hummingbird.
0:16:38 > 0:16:40It has to be said, with a tail like that,
0:16:40 > 0:16:43he's already making quite an impression.
0:16:44 > 0:16:46But to win over his female,
0:16:46 > 0:16:49he'll need to hover and wave his enormous tail flags
0:16:49 > 0:16:51at the same time.
0:17:04 > 0:17:06It's such an endurance test,
0:17:06 > 0:17:10every now and then, he needs to take a little rest.
0:17:16 > 0:17:18With every leap,
0:17:18 > 0:17:20this lesser florican is trying to prove he's fitter
0:17:20 > 0:17:22than all the other males.
0:17:22 > 0:17:28And today, just to make sure, he's going to do 500 of them.
0:17:36 > 0:17:39In the dense jungles of Costa Rica,
0:17:39 > 0:17:42there's little room for showing off.
0:17:42 > 0:17:44So one amorous male woos a female
0:17:44 > 0:17:46with an altogether more cunning tactic.
0:17:49 > 0:17:52Meet the male glasswing butterfly.
0:17:56 > 0:17:58He's got see-through wings precisely
0:17:58 > 0:18:01because he doesn't want to stand out from the crowd.
0:18:05 > 0:18:09There are just too many jungle predators around for that.
0:18:12 > 0:18:14He too uses the air to show off,
0:18:14 > 0:18:17but it's an aerial display like no other.
0:18:19 > 0:18:22He's going to use the air to carry an irresistible message
0:18:22 > 0:18:26to a female and to get her to come to him.
0:18:30 > 0:18:33On his wings, he has little bunches of hair
0:18:33 > 0:18:36loaded with his own distinctive pheromone perfume.
0:18:42 > 0:18:46The perfume wafts through the trees carrying a specially coded message
0:18:46 > 0:18:48invisible to others.
0:18:50 > 0:18:55It tells the female who he is and how many poisonous plants
0:18:55 > 0:18:56he's managed to eat.
0:18:59 > 0:19:01Because he stores the poisons in his body
0:19:01 > 0:19:05and uses them to show how distasteful he is to predators.
0:19:10 > 0:19:13So, to a female checking out the males in the jungle,
0:19:13 > 0:19:16it's good to have bad taste.
0:19:20 > 0:19:23The secret message wafting invisibly through the jungle says,
0:19:23 > 0:19:28"I'm here, I'm male and I taste worse than all the others."
0:19:32 > 0:19:36She's hooked and follows the trail of his irresistible odour.
0:19:47 > 0:19:49It's a clever trick,
0:19:49 > 0:19:52the male attracts a female without attracting predators.
0:19:55 > 0:19:57When it comes to finding a mate,
0:19:57 > 0:20:01males will try anything that works to give them an edge.
0:20:01 > 0:20:03And with the skies so full of competition,
0:20:03 > 0:20:06it pays to be cunning like the glasswing.
0:20:09 > 0:20:12But once animals have paired up,
0:20:12 > 0:20:14it's not long before offspring arrive,
0:20:14 > 0:20:17and they need looking after.
0:20:19 > 0:20:21This is Oregon, USA.
0:20:23 > 0:20:25Home to the kingbirds.
0:20:27 > 0:20:31They're an ordinary looking couple working hard to raise a family.
0:20:33 > 0:20:35But don't be deceived,
0:20:35 > 0:20:38these birds are remarkable.
0:20:40 > 0:20:43The male has picked the perfect home,
0:20:43 > 0:20:45the air is thick with insects to eat,
0:20:45 > 0:20:48but he'll have to work hard to catch them for his family.
0:20:49 > 0:20:54He's agile enough to take insects on the wing, and that's no mean feat.
0:21:22 > 0:21:25The top prize for a kingbird is this.
0:21:27 > 0:21:29A big, juicy dragonfly.
0:21:33 > 0:21:36They're more manoeuvrable than him,
0:21:36 > 0:21:39and they're one of the fastest insects in the world,
0:21:39 > 0:21:41topping 50 kilometres an hour.
0:21:46 > 0:21:49But the kingbird is faster.
0:21:49 > 0:21:51This is speed versus agility.
0:22:01 > 0:22:04He'll work hard like this to feed his chicks
0:22:04 > 0:22:06for nearly for nearly two months.
0:22:06 > 0:22:07His commitment is total.
0:22:10 > 0:22:12But his true colours are about to be revealed.
0:22:12 > 0:22:15He's spotted danger in his neighbourhood.
0:22:15 > 0:22:17CROWING
0:22:20 > 0:22:21Ravens.
0:22:24 > 0:22:26They'd kill his whole family in minutes given the chance.
0:22:30 > 0:22:32He's going to have to defend his offspring.
0:22:37 > 0:22:41Ravens are clever, and they're four times bigger than him.
0:22:48 > 0:22:51But no-one is going to hurt his family.
0:22:57 > 0:22:59As formidable as the ravens are,
0:22:59 > 0:23:02the kingbird has an unexpected side to his character.
0:23:02 > 0:23:07Sheer. Obsessive. Belligerence.
0:23:10 > 0:23:13What he's about to do seems almost suicidal.
0:23:21 > 0:23:23He manoeuvres into the raven's blind spot.
0:23:27 > 0:23:33He hassles it, landing on its back, even stabs at its neck.
0:23:33 > 0:23:34The raven could kill him.
0:23:37 > 0:23:40But as long as he holds this position, he's in control.
0:23:45 > 0:23:48Those superb acrobatic skills that helped him
0:23:48 > 0:23:52chase down dragonflies are now being used to help keep his family safe.
0:24:06 > 0:24:10Kingbirds will take on anything,
0:24:10 > 0:24:12including large birds of prey.
0:24:16 > 0:24:19They've even been seen having a go at low-flying aircraft.
0:24:32 > 0:24:36A combination of spectacular flying agility and an almost
0:24:36 > 0:24:40psychopathic attitude makes the skies above a kingbird nest
0:24:40 > 0:24:42a little less crowded than they might be,
0:24:42 > 0:24:45and the chicks, a little safer.
0:24:46 > 0:24:48That's dedication.
0:24:56 > 0:24:59The kingbird takes huge risks to give his young a flying start
0:24:59 > 0:25:01in this competitive world.
0:25:03 > 0:25:07But there's a tiny animal from Texas that takes parenthood
0:25:07 > 0:25:09to an even greater extreme.
0:25:15 > 0:25:17The phorid fly.
0:25:17 > 0:25:20Smaller than a pin's head, she's a mother.
0:25:20 > 0:25:23And right now, she needs to lay her eggs and secure a safe future
0:25:23 > 0:25:25for her offspring.
0:25:30 > 0:25:31But to do this,
0:25:31 > 0:25:35she must face one of the most feared animals in Texas.
0:25:37 > 0:25:38Fire ants.
0:25:39 > 0:25:41In their thousands.
0:25:43 > 0:25:46They have a vicious bite and a venomous sting.
0:25:47 > 0:25:50They'll kill any insect that crosses their path.
0:25:57 > 0:26:00But incredibly, these vicious predators aren't going to eat
0:26:00 > 0:26:02the phorid fly's young,
0:26:02 > 0:26:05the young phorid flies are going to eat them.
0:26:08 > 0:26:12First, the mother must pull off one of the greatest daredevil
0:26:12 > 0:26:14flying missions in the natural world -
0:26:14 > 0:26:18she's going to lay her eggs on living fire ants.
0:26:21 > 0:26:25She's going to have to do some serious precision flying,
0:26:25 > 0:26:27or she'll be killed herself.
0:26:28 > 0:26:30How she does it can only be fully understood
0:26:30 > 0:26:32by watching in slow motion.
0:26:37 > 0:26:40First, she hovers as close as possible to her victim
0:26:40 > 0:26:43but just out of reach of the ants' jaws.
0:26:44 > 0:26:48The risk is finely balanced, just a breath of wind and she's dinner.
0:27:08 > 0:27:11Now she's ready to quickly deposit an egg in a chink
0:27:11 > 0:27:13in the ant's armour, at a leg joint.
0:27:14 > 0:27:18From start to finish, it takes just one sixtieth of a second.
0:27:37 > 0:27:41Once attacked, the ants send out a chemical alarm to warn the others.
0:27:43 > 0:27:47They hide, crowding under any available cover,
0:27:47 > 0:27:51making it much harder for the phorid fly to get at them.
0:27:53 > 0:27:56But she has over 100 eggs still to lay.
0:27:57 > 0:28:00She's going to have to up her game and test her hovering skills
0:28:00 > 0:28:03to the max if she's going to deliver her cargo successfully.
0:28:37 > 0:28:39Her daredevil mission is accomplished.
0:28:41 > 0:28:44But the story isn't over for the ants.
0:28:46 > 0:28:48Inside each ant,
0:28:48 > 0:28:51the fly larva has taken over the ant's mind,
0:28:51 > 0:28:54reprogramming it to walk off like a zombie.
0:28:56 > 0:29:00The ant finally dies safely away from its colony
0:29:00 > 0:29:02where the fly larva can grow up in peace.
0:29:06 > 0:29:10The ant's zombie body now becomes perfect phorid fly baby food.
0:29:16 > 0:29:20For two weeks, the fly larva eats the ant from the inside.
0:29:26 > 0:29:30A tiny new phorid fly stretches her wings for the first time.
0:29:36 > 0:29:40Soon, like her mother, she'll fly her own mission impossible,
0:29:40 > 0:29:43a hair's breadth from a fire ant's jaws.
0:29:52 > 0:29:56At every stage of their lives, animals are doing what it
0:29:56 > 0:29:58takes to stay ahead of the rest
0:29:58 > 0:30:01to survive and raise a family.
0:30:01 > 0:30:02But in our crowded skies,
0:30:02 > 0:30:06they face competition from others at every turn.
0:30:06 > 0:30:10With so many lives interacting, colliding and competing
0:30:10 > 0:30:12and so much pressure to succeed,
0:30:12 > 0:30:16animals have had to push their flying abilities to the extreme,
0:30:16 > 0:30:18taking huge risks with their own lives.
0:30:31 > 0:30:34Up here, it can be tough to find food...
0:30:37 > 0:30:40..win a mate...
0:30:40 > 0:30:42or secure a future for your offspring.
0:30:46 > 0:30:50Life in the air is a life of intense competition.
0:30:53 > 0:30:55And where there's competition,
0:30:55 > 0:30:59there are animals who choose not to play by the rules.
0:31:01 > 0:31:04Few are sneakier than an inhabitant of tropical seas
0:31:04 > 0:31:07and islands around the world -
0:31:07 > 0:31:08the frigate bird.
0:31:12 > 0:31:17This pterodactyl-shaped bird has a curious problem.
0:31:17 > 0:31:22Remarkably for a sea bird, its feathers aren't waterproof.
0:31:22 > 0:31:25If it gets too wet, it'll sink and drown.
0:31:31 > 0:31:35That's obviously not good for a bird that needs to catch fish.
0:31:35 > 0:31:38So the frigate bird uses its unique flying speed
0:31:38 > 0:31:42and agility to catch fish another, less honest, way.
0:31:46 > 0:31:48It steals fish from others.
0:31:49 > 0:31:51It's a flying pirate.
0:31:54 > 0:31:57This time, its victim is a red-billed tropic bird.
0:32:02 > 0:32:06The frigate bird is going to force it to give up its last meal,
0:32:06 > 0:32:08and that means putting it under serious pressure.
0:32:38 > 0:32:41The tropic bird is a superb flier,
0:32:41 > 0:32:43but the frigate bird pirate is better.
0:32:45 > 0:32:49His wings are unusually large, but his body remains light.
0:32:49 > 0:32:52These two things combined deliver the most extraordinary
0:32:52 > 0:32:54agility in the air.
0:32:55 > 0:32:57The frigate bird can, in theory,
0:32:57 > 0:33:00out manoeuvre any other sea bird in the world.
0:33:02 > 0:33:04Perfect skills for a pirate of the skies.
0:33:18 > 0:33:22But the tropic bird isn't going to give up its hard-earned meal easily.
0:33:53 > 0:33:56When the tropic bird finally gives up its dinner,
0:33:56 > 0:34:00the frigate bird is in precisely the right spot for the catch.
0:34:07 > 0:34:09When it comes to aerial combat,
0:34:09 > 0:34:12it takes a lot to beat this thieving pirate.
0:34:21 > 0:34:24Our crowded skies are a competitive battle zone,
0:34:24 > 0:34:28with tussles between species going on all the time,
0:34:28 > 0:34:31as they've done for millions of years.
0:34:35 > 0:34:39But just occasionally, the underdog fights back
0:34:39 > 0:34:41and outsmarts its attacker.
0:34:45 > 0:34:46Take this moth.
0:34:48 > 0:34:50It can seem pretty incompetent in the air,
0:34:50 > 0:34:54with weak and fluttery flight and a bad sense of direction.
0:34:57 > 0:34:59It can blame that on its ancestors.
0:35:02 > 0:35:07100 million years ago, insects had the night sky to themselves.
0:35:07 > 0:35:09They didn't need to be strong fliers
0:35:09 > 0:35:12because there wasn't much out there to get them.
0:35:14 > 0:35:16But then along came new, intelligent,
0:35:16 > 0:35:20highly-equipped creatures that could hunt them down easily.
0:35:27 > 0:35:30They are the only mammals that have ever learnt to fly,
0:35:30 > 0:35:32and many could see in the dark.
0:35:52 > 0:35:53Bats.
0:35:56 > 0:35:58Bats were onto something.
0:35:58 > 0:36:00There was a great feast to be had in the night.
0:36:01 > 0:36:06To a moth, this is a sophisticated, highly dangerous enemy.
0:36:08 > 0:36:11A bat finds its prey using echolocation.
0:36:14 > 0:36:18Literally, it locates using echoes.
0:36:18 > 0:36:21You could say it sees using sound.
0:36:23 > 0:36:28It sends out clicks into the air, as many as 200 a second.
0:36:28 > 0:36:32If the clicks hit anything, they bounce back as echoes.
0:36:33 > 0:36:37It's by listening to those echoes in the darkness a bat can pick
0:36:37 > 0:36:40out its surroundings, even a moth.
0:36:44 > 0:36:48As the bat approaches its victim, the clicks get faster,
0:36:48 > 0:36:52creating a buzz of sound that helps it home in on its target.
0:36:57 > 0:37:00These sounds all happen beyond our human hearing.
0:37:01 > 0:37:04But we can see them as sound waves.
0:37:05 > 0:37:07First searching.
0:37:09 > 0:37:10Then approaching.
0:37:11 > 0:37:14And then finally, the attack.
0:37:19 > 0:37:24So a bat is a super flyer with added superpowers,
0:37:24 > 0:37:26and that's hard to beat.
0:37:29 > 0:37:33If they were going to survive, moths had to raise their own game.
0:37:35 > 0:37:38Some of them began to hear the bats coming.
0:37:41 > 0:37:43When they hear the buzz of an attacking bat,
0:37:43 > 0:37:45these moths take evasive action.
0:37:46 > 0:37:48They drop out of the sky.
0:37:51 > 0:37:53Simple, but effective.
0:37:58 > 0:38:01An arms race had begun between bats and moths,
0:38:01 > 0:38:05each trying to out compete each other in the night sky.
0:38:06 > 0:38:10Eventually, a race of super moths emerged.
0:38:13 > 0:38:16Super moths like this tiger moth.
0:38:16 > 0:38:19Its superpowers have only recently been explained.
0:38:27 > 0:38:31The tiger moth can vibrate a tiny membrane under its wing.
0:38:38 > 0:38:42This produces a special high-frequency sound
0:38:42 > 0:38:44to confuse bats.
0:38:44 > 0:38:46When a bat attacks,
0:38:46 > 0:38:47the secret weapon is deployed.
0:38:55 > 0:38:57The moth's special sound jams
0:38:57 > 0:38:59the bat's echolocation system,
0:38:59 > 0:39:01so it can't see with sound properly.
0:39:02 > 0:39:04It's enough of a smokescreen
0:39:04 > 0:39:06to allow the moth to escape,
0:39:06 > 0:39:09leaving the confused bat to try and find another.
0:39:14 > 0:39:18Every night, around the world, hi-tech aerial battles like this
0:39:18 > 0:39:20take place with sophisticated weaponry,
0:39:20 > 0:39:24changing the odds, as predator is pitched against prey.
0:40:13 > 0:40:15Bat versus moth,
0:40:15 > 0:40:18aerial competition that's been played out over millions
0:40:18 > 0:40:21of years between billions of rivals,
0:40:21 > 0:40:23where the tiniest advantage may make
0:40:23 > 0:40:27all the difference in the fierce battles that rage in the skies.
0:40:31 > 0:40:35If you're caught in a one-on-one life or death battle in the sky
0:40:35 > 0:40:38and you don't have a secret weapon up your sleeve,
0:40:38 > 0:40:42you'd better be able to out-fly your assailant.
0:40:42 > 0:40:45As a lone flyer, you have few other options.
0:40:46 > 0:40:49But there is one way to beat even the best aerial hunter.
0:40:51 > 0:40:52And that's teamwork.
0:40:59 > 0:41:03A group is almost impossible to sneak up on without being noticed.
0:41:09 > 0:41:13But there are other reasons that animals move together like this.
0:41:16 > 0:41:20Predators can only chase one of you at a time.
0:41:22 > 0:41:26The way they see has evolved to focus on just one animal.
0:41:30 > 0:41:33Faced with a swirling flock, they struggle to focus.
0:41:33 > 0:41:36It's information overload.
0:41:47 > 0:41:50Flocking is a really effective strategy,
0:41:50 > 0:41:53and many birds do this all over the world.
0:41:54 > 0:41:56But how can they fly so fast
0:41:56 > 0:41:59and so close to each other without colliding?
0:41:59 > 0:42:02And who is deciding where to go?
0:42:02 > 0:42:05Take starlings.
0:42:05 > 0:42:08Their flocking behaviour is world-famous,
0:42:08 > 0:42:12it even has a special name - a murmuration.
0:42:16 > 0:42:18Confusing to a predator,
0:42:18 > 0:42:21it's one of the most breathtaking sights in nature.
0:42:49 > 0:42:53Hundreds of thousands of individual birds are moving as one,
0:42:53 > 0:42:58and amazingly, there's no single bird in charge of the plan.
0:42:58 > 0:43:02Just how these complex aerial displays work has baffled us
0:43:02 > 0:43:05for centuries and has only just recently been explained.
0:43:06 > 0:43:10Remarkably, the truth about their complexity is rather simple.
0:43:10 > 0:43:14To understand how it works, imagine you could fly
0:43:14 > 0:43:17into a giant flock alongside one single starling.
0:43:23 > 0:43:25How she flies is all to do
0:43:25 > 0:43:28with what her seven closest neighbours are up to.
0:43:33 > 0:43:35As the flock moves,
0:43:35 > 0:43:37those seven might change,
0:43:37 > 0:43:39but the principle stays the same.
0:43:41 > 0:43:44Every starling in the flock is following three simple rules.
0:43:48 > 0:43:51Firstly, as you fly, steer towards each other.
0:43:56 > 0:44:00Secondly, if any of your seven neighbours turn, then you turn.
0:44:05 > 0:44:07Finally, don't crowd each other.
0:44:13 > 0:44:16Amazingly, that's all there is to it.
0:44:23 > 0:44:27Inside a flock, individual birds are making these simple decisions
0:44:27 > 0:44:30in hundredths of a second, again and again.
0:44:31 > 0:44:34It's enough to confuse a predator.
0:44:34 > 0:44:37And when half a million birds do it altogether,
0:44:37 > 0:44:39the results are spectacular.
0:45:05 > 0:45:09So how do we know precisely that this incredible spectacle is
0:45:09 > 0:45:13the result of just three simple rules and seven near neighbours?
0:45:14 > 0:45:17The answer lies in what you see here.
0:45:18 > 0:45:22This swirling mass of birds doesn't actually exist in the natural
0:45:22 > 0:45:25world, it exists inside a computer.
0:45:27 > 0:45:30It's a computer simulation, with virtual birds
0:45:30 > 0:45:34created by scientists trying to work out how flocks work.
0:45:41 > 0:45:45Incredibly, this computer-generated flock looks
0:45:45 > 0:45:47and behaves exactly like the real thing.
0:45:48 > 0:45:51Each bird is following its seven neighbours
0:45:51 > 0:45:53and using the same three rules.
0:45:55 > 0:45:57Watch a real flock anywhere on earth...
0:45:58 > 0:46:01..and it will be working in exactly the same way.
0:46:30 > 0:46:33In our crowded and competitive skies,
0:46:33 > 0:46:37this surely is the ultimate defence against an airborne predator
0:46:37 > 0:46:40and one of nature's greatest flying stunts.
0:46:44 > 0:46:47Our skies are teeming with life,
0:46:47 > 0:46:51every creature trying to find its way and to survive.
0:46:54 > 0:46:56If you can overcome the challenges of life in the air,
0:46:56 > 0:46:59there are great opportunities to be had.
0:46:59 > 0:47:02It's all about finding your place in the sky
0:47:02 > 0:47:05and picking a winning strategy.
0:47:05 > 0:47:10For some, it's enough just to beat gravity for a few seconds.
0:47:10 > 0:47:13For others, it means taking a leap of faith.
0:47:16 > 0:47:19Extraordinary specialist techniques might just give you an edge.
0:47:22 > 0:47:26All these animals have skills we humans can only wonder at.
0:47:27 > 0:47:30Every time an animal takes to the air,
0:47:30 > 0:47:33it seems to be performing its own personal miracle.
0:47:37 > 0:47:40Defying gravity to live in a world
0:47:40 > 0:47:43that we are only just beginning to understand.
0:48:04 > 0:48:07In Life In The Air, the team's mission was to reveal the incredible
0:48:07 > 0:48:11abilities of airborne animals in more detail than ever before.
0:48:11 > 0:48:15To do it required some extreme perseverance
0:48:15 > 0:48:17and a range of approaches.
0:48:17 > 0:48:20Some animal stars could be filmed in controlled conditions,
0:48:20 > 0:48:24allowing the team to move their cameras alongside them.
0:48:24 > 0:48:27Others could only be filmed on their own terms out in the wild.
0:48:27 > 0:48:28Blimey!
0:48:30 > 0:48:33The most challenging filming in the wild involved the smallest
0:48:33 > 0:48:37and fastest of flyers - the Anna's hummingbird.
0:48:39 > 0:48:41To film their record-breaking dive,
0:48:41 > 0:48:45the team needed a secret weapon - cameraman Barrie Britton.
0:48:51 > 0:48:54Filming birds requires keeping them in shot
0:48:54 > 0:48:56and in focus from great distances.
0:48:56 > 0:49:01Few people on the planet can do it, and Barrie is one of the best.
0:49:06 > 0:49:08But this was the first time he'd attempted to film
0:49:08 > 0:49:10the legendary Anna's hummingbird.
0:49:15 > 0:49:18On the edge of a university campus in California,
0:49:18 > 0:49:20he has his first view of the male's display.
0:49:24 > 0:49:28The hummingbird has gone really high in the sky,
0:49:28 > 0:49:30and it's coming in. Whoa!
0:49:32 > 0:49:35He's so small and he's just moving so quickly.
0:49:37 > 0:49:40I think it's going to be a real challenge to film it.
0:49:40 > 0:49:42Hummingbird scientist Christopher Clark
0:49:42 > 0:49:44knows a trick that might help.
0:49:44 > 0:49:47He uses a stand-in female bird to attract the males.
0:49:47 > 0:49:49The birds are going at the speed of freeway traffic.
0:49:49 > 0:49:52Barrie is able to piggyback on Chris's studies
0:49:52 > 0:49:53to give him a chance.
0:49:55 > 0:49:58And as backup, the team have brought their own range
0:49:58 > 0:49:59of stand-in models.
0:49:59 > 0:50:03First up, a slightly moth-eaten stuffed bird.
0:50:03 > 0:50:06According to the scientists,
0:50:06 > 0:50:09this female, the way her tail is,
0:50:09 > 0:50:10means that she's a bit...
0:50:10 > 0:50:13she looks a bit more up for it than the others.
0:50:13 > 0:50:17The model is so enticing, the male skips courtship altogether.
0:50:20 > 0:50:22Onto model number two.
0:50:22 > 0:50:24A more modest embroidered female.
0:50:26 > 0:50:27Playing hard to get,
0:50:27 > 0:50:30she's perfect for encouraging the males to perform
0:50:30 > 0:50:32their courtship display.
0:50:32 > 0:50:35In fact, they're so keen to show off to her, the crew need to cover
0:50:35 > 0:50:38her up while Barrie prepares.
0:50:38 > 0:50:39I'm ready.
0:50:39 > 0:50:43With the set-up sorted, it's now down to Barrie versus the birds.
0:50:47 > 0:50:48Oh, here he is.
0:50:51 > 0:50:53- Whoa! - HE LAUGHS
0:50:53 > 0:50:55That's really quick.
0:50:57 > 0:50:59You think you're so clever!
0:51:09 > 0:51:10Blimey!
0:51:11 > 0:51:14I'm not sure this is going to work, I'm just trying.
0:51:16 > 0:51:18Things are starting to come together.
0:51:18 > 0:51:22That's got to be good, it's got to be good.
0:51:25 > 0:51:29Meanwhile, thousands of miles away in the cloud forests of Ecuador,
0:51:29 > 0:51:32another team are also challenged with filming a small,
0:51:32 > 0:51:33fast-moving animal.
0:51:36 > 0:51:39Their mission is to fly alongside wild bats
0:51:39 > 0:51:41hunting in complete darkness.
0:51:47 > 0:51:51Scientist Nick Dowdy is taking the crew to his study site within
0:51:51 > 0:51:54the forest, where he carries out research on how wild bats
0:51:54 > 0:51:55hunt tiger moths.
0:51:58 > 0:52:01Huge amounts of specialist equipment are required.
0:52:01 > 0:52:04And unable to get this deep into the jungle,
0:52:04 > 0:52:07the team's first task is to bring the jungle to them.
0:52:12 > 0:52:15A studio within the forest will be a temporary new home for the bats.
0:52:18 > 0:52:19It'll replicate the jungle
0:52:19 > 0:52:23but will also be rigged with kit by cameraman Rob Drewett.
0:52:27 > 0:52:31It takes five days to get everything just right before switching
0:52:31 > 0:52:34to night shifts, entering the world of the bats.
0:52:36 > 0:52:38Challenged with flying his camera alongside them,
0:52:38 > 0:52:41Rob has a stabilising pulley system.
0:52:45 > 0:52:46And his state-of-the-art infrared camera
0:52:46 > 0:52:49is able to slow down the images over 40 times.
0:52:53 > 0:52:57Rob's also relying on some rather less technical equipment.
0:52:57 > 0:53:00I'm having to go around and just make sure there's no
0:53:00 > 0:53:02holes for them to get out of the enclosure.
0:53:05 > 0:53:07Fingers crossed we've got it sorted.
0:53:10 > 0:53:14I think we have, it looks pretty good.
0:53:14 > 0:53:17So even like that, they're going to get out, aren't they?
0:53:17 > 0:53:20While Rob double checks, there's also time for final kit tests
0:53:20 > 0:53:22before everything is bat-ready.
0:53:22 > 0:53:24- You're flapping! - HE LAUGHS
0:53:28 > 0:53:30Nick is trained to safely capture
0:53:30 > 0:53:33and release wild bats for use in his studies.
0:53:33 > 0:53:37This expertise ensures the welfare of the animals during filming.
0:53:38 > 0:53:43It's also an opportunity for Nick to gain insights into their behaviour.
0:53:43 > 0:53:46CLICKING
0:53:46 > 0:53:49Echolocation clicks from a bat detector show
0:53:49 > 0:53:52the occupants are getting to know their new home.
0:53:55 > 0:53:56Now filming can finally begin.
0:54:01 > 0:54:04Night after night, Rob starts to get the shots he needs.
0:54:06 > 0:54:10And the controlled conditions of the forest studio come into their own.
0:54:10 > 0:54:11- Oh, here we go.- Here we go.
0:54:13 > 0:54:16- Yes, it's pretty good.- Yeah.
0:54:16 > 0:54:20But Rob's greatest challenge is yet to come - filming the bats hunting.
0:54:26 > 0:54:30Back in California, the hummingbird crew have hit a problem.
0:54:30 > 0:54:32The star model has lost its appeal
0:54:32 > 0:54:35and instead of diving, the males are now attacking.
0:54:38 > 0:54:41There's no option but to turn to the real deal,
0:54:41 > 0:54:44a female Anna's hummingbird.
0:54:44 > 0:54:46For these shy creatures,
0:54:46 > 0:54:49Barrie has to rely on more traditional techniques.
0:54:49 > 0:54:51We just need everything to kind of line up.
0:54:51 > 0:54:53We need the females to come, land on the perch
0:54:53 > 0:54:57and the male has to be looking the right way.
0:54:57 > 0:54:58It's going to be a test of patience,
0:54:58 > 0:55:02filming all day, every day, in a hide in the Californian heat.
0:55:06 > 0:55:08The shoot is in its last few days,
0:55:08 > 0:55:10and finally, everything is falling into place.
0:55:10 > 0:55:13Barrie's able to capture interactions between the male
0:55:13 > 0:55:16and a real female, and reveal the world's fastest courtship
0:55:16 > 0:55:18display in incredible detail.
0:55:23 > 0:55:25That's really nice, really good.
0:55:28 > 0:55:32Back in Ecuador, Rob also faces a waiting game.
0:55:32 > 0:55:35He's truly immersed in the bat's world,
0:55:35 > 0:55:37becoming nocturnal himself
0:55:37 > 0:55:39as he strives to capture their hunting behaviour.
0:55:40 > 0:55:43There's no way of knowing exactly when the bats will strike.
0:55:43 > 0:55:45And once triggered, the camera needs
0:55:45 > 0:55:48at least seven seconds to save the shot.
0:55:48 > 0:55:50Oh, that was close.
0:55:50 > 0:55:52It's frustrating for Rob
0:55:52 > 0:55:55if the action happens before the camera re-arms.
0:55:56 > 0:55:57And then...
0:55:57 > 0:55:58Ah, no. Not now, though.
0:55:58 > 0:56:00- ..catastrophe.- No, armed?
0:56:00 > 0:56:02Armed.
0:56:02 > 0:56:03Ah!
0:56:03 > 0:56:05Look at this.
0:56:05 > 0:56:07- Ah!- Oh, my God.
0:56:10 > 0:56:12This is disastrous.
0:56:12 > 0:56:14I'm a bit nervous about using this camera -
0:56:14 > 0:56:17it crashed and we lost a whole night's footage.
0:56:17 > 0:56:22So fingers crossed it doesn't do that again.
0:56:22 > 0:56:25Having worked through the night for over two whole weeks, Rob's spirits
0:56:25 > 0:56:30are low, and he only has a few days left.
0:56:30 > 0:56:31But he's not one for quitting.
0:56:31 > 0:56:34Am I armed?
0:56:34 > 0:56:35Yep.
0:56:35 > 0:56:37Oh, that was in frame!
0:56:39 > 0:56:41OK, let's have a look at that one.
0:56:41 > 0:56:44I think we might have got that. Yes!
0:56:44 > 0:56:46Ah, that's nice.
0:56:46 > 0:56:48Great, we got one.
0:56:48 > 0:56:50- Yes!- Well done, good work.
0:56:50 > 0:56:53After many sleepless nights, Rob's perseverance pays off,
0:56:53 > 0:56:56helped by a successful partnership with science, a little
0:56:56 > 0:57:00technology and a great performance from the masters of the night sky.
0:57:04 > 0:57:09In total, crews have worked over 300 days on location
0:57:09 > 0:57:12to film incredible animals in action in the skies.
0:57:17 > 0:57:19Life in the air has been captured
0:57:19 > 0:57:22in greater detail than ever before.
0:57:22 > 0:57:24Seeing how animals survive
0:57:24 > 0:57:30and thrive up here has revealed just what it takes to master the skies.