Taking to the Air Life in the Undergrowth


Taking to the Air

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A summer evening on the Koros river in central Europe.

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Its waters are mirror-smooth

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but, on this particular day of the year, all that is about to change.

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Giant mayflies, Europe's largest,

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are starting to rise to the surface and struggle out of the skins in which they lived as larvae.

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At first they come in ones and twos.

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Soon there will be millions.

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For two years, they have lived underwater.

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Now they must fly to find a mate.

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This should be the climax of their lives.

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The first to appear are quickly taken by predators.

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But soon the swarms are so huge that neither fish nor birds can make any impact on them.

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The first mayflies to emerge in this mass hatching on this river in Hungary are all males.

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As soon as they free themselves from their larval skins on the surface,

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they take off and seek safety in the banks and there they hang in trees and bushes,

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or indeed on my finger. The reason they have to rest like this

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is because they still have to make one final moult.

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Their wings that were transparent now have a handsome blue tinge

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and the elegant filaments at the end of their abdomens are even longer than before.

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They are looking for mates... but they have a problem.

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They can't feed for they have neither mouth nor stomach.

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They have to fuel their flight entirely from the reserves of fat

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that they built up when they were larvae feeding in the river.

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But that fat will only last them for about half an hour of flight time.

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So the race to mate now becomes a frantic one.

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The females begin to rise to the surface and the males fly up and down the river searching for them.

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As soon as they find one, they all pounce on her, competing to be the one to fertilise her eggs.

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But the struggle of doing so saps their limited energy.

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Before long they begin to run out of fuel

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and, though they flutter despairingly,

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they can't maintain themselves in the air.

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Win or lose, their lives are almost over

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and dead bodies start to litter the surface of the water.

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But the females are still in the air.

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They are flying upstream, judging the depth of the river

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and the currents in it, to find a place where they can lay their eggs

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so that they will float downriver to the same sort of place where the adults themselves lived as larvae.

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The ancestral mayflies were among the first creatures of any kind

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to take to the air about 320 million years ago.

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For them, as for their living descendants,

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flight was a brief but invaluable way of finding a mate and expanding their breeding territories.

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The river has also been the home of another kind of insect with an equally ancient ancestry

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and it too is beginning to emerge from the water.

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Bigger and more ferocious than the mayfly larvae, it has been feeding on tadpoles and even small fish.

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But that phase of its life is over.

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Now each one has to haul itself out of the water and into the air.

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On the top of its thorax, it carries a bulging back-pack.

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It hunches itself and its outer skin splits.

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A very different creature begins to appear.

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White threads are drawn out of its flanks.

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They are the linings of thin tubes that penetrate deep into its body -

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air tubes that enable the insect to breathe now that it is out of water.

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It gulps air...

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inflating its body, forcing fluid into the bundle on its back.

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Its wings begin to unfurl.

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Ten minutes later...

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the wings open.

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They will never close again.

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Next, the huge muscles within its thorax must be exercised to prepare them for action.

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And it's away.

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Dragonflies, like mayflies, belong to the most ancient group of insects that flew over the land

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and here in the museum in Harvard there are fossils of them that are 150 million years old.

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They are almost identical with species that are still flying today.

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However they are by no means the oldest.

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We know that there were other dragonflies even earlier,

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225 million years ago,

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that were flying through the swamps.

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We don't have complete specimens of any of those

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but there are some tantalising and amazing fragments.

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And here is one.

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This marvellously preserved wing

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has very much the same pattern of veins supporting panels of membranes as living species.

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The thing that makes it different

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is its size.

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From base to tip, it measures 12 inches, 30 centimetres.

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Little imagination is needed to replace the membrane that must have been there.

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This insect must have had a wing-span as big as a seagull's.

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Vibrating THESE wings

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preparing for flight must have been a formidable business.

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A creature this size must have been at least ten times heavier than the largest insect flying today.

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How did it manage to get into the air?

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One suggestion is that in those far-off times there was much more oxygen in the air

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and that would have given the extra power needed to beat these huge wings.

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But it is a fair guess that this ancient pioneer of the skies

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flew with much the same technique as dragonflies do today.

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Living dragonflies can reach speeds of nearly 40 miles an hour

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and fly several miles in their search for new territory.

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They are all aerial hunters, relying on their supreme aeronautical skills

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to snatch their prey from the sky.

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Their great agility in the air comes from being able to beat

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each of their two pairs of wings quite independently.

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You can see clearly that they do this...

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when the camera slows down the action 400 times.

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This one is coming in to its perch.

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Perfect control is essential to make all the tiny adjustments needed

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for an accurate pinpoint touchdown.

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All dragonflies, when they perch, hold their wings outstretched.

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But they have close relations, damselflies,

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and they perch with their wings closed above their backs.

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Mosquitoes stand little chance when damsels go hunting.

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But flight for damsels, as for dragonflies and mayflies,

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is primarily the means to find a mate and to breed

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and to do that they, like the others, need water.

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Flight is itself an important element in their courtship.

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These blue males must first establish a territory for themselves above open water

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and that involves aerial jousts that can last for hours.

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Mature females,

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whose wings in this species are not blue but golden brown,

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are attracted to those males who control good places for egg-laying.

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But the males must nonetheless display the correct wing signals.

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This one, patrolling his territory, is using a special flight,

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flaunting his handsome wings, inviting females to join him.

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A female signals her willingness to consider doing so with a flick of her wings.

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So now he treats her to his full display.

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The female's tail-up posture is apparently a signal

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that declares that she is not yet sufficiently impressed.

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Now, it seems, he's got it right -

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her tail is pointing downwards.

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He grabs the back of her neck with the claspers at the end of his abdomen.

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She brings her abdomen forward to reach a chamber under his thorax where he stores his sperm.

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His first action, though, is to scour out her genital tract

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to remove any sperm that might be there from a previous mating.

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Only when he's done that will he inject his own sperm.

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And now he must show her the best places in his territory for laying eggs.

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He flies up and down, with his tail curled, and lands on a suitable piece of vegetation.

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The female settles down to lay, cutting slits in the plant stems

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with her ovipositor and inserting an egg into each one.

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She may lay as many as 30.

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And all the time, the male keeps guard lest rival males should try to mate with her.

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In other damsel species, the males make sure

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that no other male can reach their partners by keeping hold of them throughout the whole process.

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The young that hatch from the eggs of these insects, the larvae,

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look very unlike their parents.

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This is a dragonfly larva.

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It is in this form that dragonflies spend most of their lives.

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The larvae of both dragonfly and damselfly are savage predators.

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They will even feed on their own kind if they get the chance.

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This particular larva has a special problem. It's a cascade damsel

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and it has to snatch prey that is swept past it by the rushing water.

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Cascade damsels are very rare and live around just a few Central American waterfalls,

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like this one in the mountains of Costa Rica.

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The adult male has to perform his courtship flight under very difficult conditions indeed.

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Somehow, he is able to fly even when he is dripping wet and he shows off to the females

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by actually flying through the cascades of water.

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To be a good breeding territory, the vertical rock surface has to be covered

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by just the right amount of water.

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Too deep, and prey may be out of reach,

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too shallow and the larvae could be picked off by birds.

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A female will only mate with a male if she approves of his choice of territory.

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And this one, it seems, does.

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This is it, and she carefully fixes her eggs to the rocks.

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But not all damsels need great areas of open water for breeding.

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In the rainforest of Central America,

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like this one here in Costa Rica, there is a damselfly

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that has managed to break the link with open expanses of water like rivers and ponds.

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It's also one of the most spectacular members of the entire family.

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The helicopter damselfly, the largest in the world with a wing-span of up to 20 centimetres.

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The males tend to frequent sunlit patches where the females can see them easily

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and they have a special lazy flapping way of flying that is, in itself, an invitation.

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But although helicopter damsels can live away from rivers and streams,

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the females nonetheless require a little water in which to lay their eggs...

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and there is just enough

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in this little hollow here.

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And with luck she will come down.

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And into the water they go.

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But these eggs have water-tight casings, so they can be laid in air.

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They're butterfly eggs. The link with water has been broken.

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Butterflies fly in a very different way from dragonflies.

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They overlap their two pairs of wings so that they flap as a single pair.

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They can't fly as fast or as aerobatically as dragonflies

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but they nonetheless are tireless in their search for the particular food that will suit their young.

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And, in the case of the cabbage white, that's cabbage.

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Now on the surface of this cabbage leaf

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there is a patch of tiny little pillbox shaped eggs.

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And when they hatch, the baby caterpillars will emerge and make an instant meal of the greenery.

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And they are already stirring.

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But the first dish on the menu is not vegetables.

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It's the shells of their own egg capsules,

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protein rich and far too nourishing to be wasted.

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That first course, however, doesn't last long.

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Now for the main dish - cabbage leaves.

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When cabbage plants are damaged, their leaves release a smell

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and that quite often attracts the attention of a rather different insect.

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It's a tiny wasp called cotesia.

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She too is trying to make sure that her young have food immediately available,

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but they like living flesh.

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So she injects her eggs into the butterfly's caterpillars.

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She does this with such surgical precision that her victims are not mortally injured

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and they continue feeding as if nothing had happened to them.

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But now much of what the caterpillars so laboriously gather

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goes to nourish the wasp grubs that are developing within them.

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As the caterpillars grow, they shed their skins.

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They do so five times until, ultimately,

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they are 800 times heavier than they were when they first hatched.

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This fully-grown caterpillar must now find shelter.

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A strand of silk trails behind it,

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silk with which it ties itself to a twig.

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And here, over a couple of days, it changes into a chrysalis.

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Those caterpillars that were injected by the cotesia wasp don't get that chance.

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The grubs within them are now emerging.

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They too spin silk which hardens to form a cocoon beneath the caterpillar's empty skin.

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Inside, the wasp grubs are transforming themselves

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and two weeks later, out come the adult wasps.

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A different future awaits the chrysalis.

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Within its shell and over a similar two weeks,

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the caterpillar's body has been broken down and reassembled

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and now the adult is ready to emerge.

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Its wings, like those of a newly-emerged dragonfly, need pumping up with liquid.

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The creature that was once an egg, then a caterpillar, then a chrysalis has attained its final incarnation.

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So another generation of cabbage whites set off to find good places for their young.

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With their fragile-looking wings and apparently erratic flight,

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butterflies might not seem to be the most powerful of flyers,

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but in fact they are extremely accomplished aeronauts

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and they can fly hundreds of miles if necessary to find the food they need.

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Some butterflies use the power of flight for another purpose -

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to escape bad weather.

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These lush sub-tropical valleys in southern Taiwan

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are warm and green all year round and in winter, they are filled by literally millions of butterflies.

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They have all come from the north of this great island, 500 miles away, for there the cold weather

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has killed off the plants on which they fed during the summer.

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In the mornings they take off from their roosts

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and head for the forest canopy, to warm themselves in the rays of the rising sun.

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They have to conserve as much energy as they can,

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so instead of using their stores of fat to warm themselves, they absorb the sun's heat.

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There are four species of crow butterflies here as well as two species of blue tiger butterflies...

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and all find enough food to sustain themselves in these warm and fertile valleys.

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Butterflies feed on liquid, nectar and the juices of rotting fruit

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and to suck it up they have, instead of jaws,

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an extraordinarily long but extremely thin tube.

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In a newly-emerged butterfly this tube is in two pieces,

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for it is in fact a highly modified pair of mouthparts.

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Each half has its own muscles and nerve supply so that the whole unit is fully movable and controllable.

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As the young butterfly prepares for adult life, these two sections

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are zipped together to form a tube like a miniature drinking straw.

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A special fluid cements the two halves together.

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The tube is largely made of a material called resilin which,

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when distorted, springs back to its original shape,

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in this case a spiral like a watch spring.

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When the muscles within it contract, it straightens into a long probe

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that the butterfly can then insert deep into a flower.

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Butterflies and moths have the largest of all insect wings

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and their great size means that they can be used very effectively

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as billboards on which to display patterns proclaiming the species of their owner.

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The patterns are produced by tiny scales that cover the wings like tiles on a roof.

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Some have a microscopic structure

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that refracts the light and gives the wing a brilliant iridescent shimmer.

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Others contain chemical pigments.

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With these lovely advertisements, a male butterfly displays to females and warns off rivals.

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Vivid patterns and bright colours are used to a much lesser degree by moths,

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for many are only active at night when colours are not easily seen.

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Moths also feed primarily on nectar which they suck up in the same way that butterflies do.

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But one moth manages to tap a food source no butterfly has yet exploited.

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Lantern bugs feed by drilling into the bark of a tree with their proboscis and sucking out the sap.

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This contains a little protein, which the bug wants,

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but a lot of sugar, most of which it doesn't want.

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So it squirts out the sweet excess and to make sure that this doesn't attract ants that might attack it,

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it fires the droplets well away from the tree trunk

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with a tiny spring-loaded spatula at the end of its abdomen.

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One enterprising species of moth regularly sits behind the bug all night

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with the curled tip of its proboscis delicately placed in the stream of droplets.

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As sugar water accumulates, so the moth sucks it up.

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Most moths, however, feed by the rather more laborious method of flying from flower to flower.

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A few, the busiest,

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do so not only at night but during the day as well.

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These are the hawk moths and there are several species of them

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gathering nectar from this buddleia bush in the south of France.

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This hawk moth can fly very fast indeed when it wants to

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but it can also hover, as it's doing now, to sip nectar

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from each of these small flowers. Beating its wings as fast as this,

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takes a great deal of energy

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so these hawk moths have to spend much of their day

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going from flower to flower sipping the nectar

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which is so rich in the carbohydrates they need to power their flight.

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They have huge forward-pointing eyes that enable them to aim their proboscis with such accuracy

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that it slips into the exact centre of each tiny flower.

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With so many minute flowers so closely bunched together,

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it would be easy for the moth to visit some twice.

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But that would waste energy and if we mark each flower as the moth drinks from it,

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it's clear that the moth, somehow or other, never does this.

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Hummingbird hawk moths have no difficulty in hovering.

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Bee hawks however, have heavier bodies

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and they sometimes use their legs to help support themselves as they work.

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Their need to keep drinking is so pressing that a female will continue to do that

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even when the male with whom she is mating seems to be trying to fly in the opposite direction.

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The buddleia plant may be a particular favourite of hawk moths

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but it is, of course, a foreigner, introduced into our gardens from China in the 19th century.

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The hawk moth's original supplies of nectar came from the flowers of the meadows.

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And they still feed there, alongside many other insects.

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This is a carpenter bee.

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Bees also have two pairs of wings but they are hooked together

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so, like those of butterflies, they operate as one.

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Bumblebees have particularly large and heavy bodies and flight, for them, can be a real effort.

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That is particularly so in spring when the mornings are cold

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and queen bumblebees are just emerging from their winter sleep.

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It is still only a few degrees above freezing, but a queen needs to get started early to look for food.

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The thick furry hairs on her body help to conserve what heat she manages to generate.

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At the moment she is only a few degrees warmer than the surrounding vegetation,

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as a thermal camera clearly shows.

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Her body is only marginally more pink than the blue leaves and moss around her.

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But she has a special way of warming up for flight.

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She can put her wings out of gear so that, without moving them,

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she can rev up the wing muscles inside

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and that raises the temperature within her thorax

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by 20 degrees centigrade or more

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as the expanding yellow image on the thermal camera indicates.

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Her body temperature is now over 30 degrees centigrade.

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At last, she has a chance of lift-off.

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She will now be able to visit the spring flowers while it is still too cold for others to do so.

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The long trumpets of the daffodils retain heat very well and they are still warm

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even after their hot-bodied visitors have left.

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Flies, back in their distant evolutionary past,

0:34:320:34:35

also had two pairs of wings, but their back pair have been reduced

0:34:350:34:40

to simple knob-ended rods.

0:34:400:34:43

These are particularly long on crane flies.

0:34:440:34:47

They are part of a fly's flight instrumentation.

0:34:470:34:51

Microscopic sensors on their upper and lower surfaces tell their owner

0:34:510:34:55

about the air currents around its body and so help in flight control.

0:34:550:34:59

They start up even before take-off.

0:34:590:35:02

Flies are such accomplished flyers that they can land upside-down on a ceiling

0:35:080:35:14

or, in this case, the underside of a twig.

0:35:140:35:18

Only when you slow down a fly's flight, here by 100 times,

0:35:280:35:32

can you fully appreciate what superb aerial control they have.

0:35:320:35:36

Some species, like these long-legged flies, flaunt their wings in courtship, just as damselflies do.

0:35:440:35:52

These dance flies are voracious hunters

0:36:010:36:03

and it is particularly important for them that they perform their dance correctly.

0:36:030:36:09

If one doesn't get it right, its partner might well eat it.

0:36:090:36:13

This performance, however, seems to have been up to standard.

0:36:400:36:43

For hoverflies,

0:37:090:37:11

arguably the most accomplished of all insect aviators,

0:37:110:37:14

immaculate aerial control is what makes a male attractive to a female.

0:37:140:37:19

A male lays claim to a mating territory by trying to stay

0:37:210:37:25

in exactly the same position in space for as long as possible.

0:37:250:37:29

That is not easy when there are others all around you, trying to do precisely the same thing.

0:37:290:37:37

It might seem that he is absolutely motionless,

0:37:370:37:41

but in fact he is having to make continual changes to adjust for slight currents in the air.

0:37:410:37:47

It is an amazing piece of acrobatics,

0:37:470:37:51

far better than anything that we can do in a helicopter.

0:37:510:37:56

And it is all done in order to impress the female,

0:37:560:38:00

to show her that he is superb at holding his territory.

0:38:000:38:06

Having to chase away rivals that come too close is an exhausting business

0:38:080:38:15

and when you are trying to maintain your hold on a particular point in mid-air,

0:38:150:38:20

even a small midge has to be chased away.

0:38:200:38:24

After a morning spent doing this, a male hoverfly may have lost as much as a third of his body weight.

0:38:310:38:38

Little wonder that he takes a break at mid-day in order to rest and refuel.

0:38:380:38:43

He dabs up nectar with mouth-parts that are shaped like a pad.

0:38:430:38:47

Having refilled his fuel tank, the male returns to his territory for the afternoon's session of hovering,

0:38:580:39:05

in the hope of attracting yet another female and mating with her.

0:39:050:39:08

Once again, with his superb eyesight,

0:39:130:39:17

he is ready to spot anything that might whiz by him at high speed that could be a female.

0:39:170:39:23

And I might just be able to fool him with a pea-shooter.

0:39:230:39:27

Although there may seem to be an extraordinarily large number of different flies in the world,

0:40:070:40:13

it is actually the beetles that are the most varied of all insect groups.

0:40:130:40:17

There are 300,000 species of them.

0:40:170:40:21

Most find their food by crawling and burrowing on the ground and to prevent their wings

0:40:210:40:26

from being damaged in the process, they have turned the front pair into protective shields.

0:40:260:40:32

Some, like weevils, keep their wing-covers permanently closed and before take-off

0:40:320:40:38

push their functional wings out of special slits.

0:40:380:40:42

Ladybirds, like most other beetles, raise their wing covers

0:40:430:40:47

and hold them clear of the hind wings throughout their flight.

0:40:470:40:50

The result could hardly be called aerodynamic and consequently their flight is rather lumbering.

0:40:500:40:56

Blister beetles are scarcely any better.

0:41:010:41:04

When a flight is over, the hind wings have to be packed away beneath the covers -

0:41:100:41:15

a process that can be so complex that it demands all the skills of a Japanese master of origami.

0:41:150:41:21

With flight playing a relatively small part in their lives, many beetles have grown very large.

0:41:380:41:45

This one, the titan beetle that lives in the forests of the Amazon,

0:41:450:41:48

is almost certainly the biggest of all insects.

0:41:480:41:52

I have to handle him with considerable care

0:41:550:41:59

because these huge mandibles at the front are powerful enough, it's said,

0:41:590:42:04

to be able to cut straight through a pencil.

0:42:040:42:09

He can fly, but he can't get into the air from the ground.

0:42:090:42:12

He's too heavy to do that, so he has to climb trees and launch himself into the air that way.

0:42:120:42:18

That is why he has got such powerful legs, armed with sharp claws.

0:42:180:42:23

The titan is now known to be the biggest of all beetles.

0:42:230:42:28

The champion is seven inches long from the tip of its mandibles to the tip of its abdomen.

0:42:280:42:35

The larva of this great monster has not yet been found

0:42:350:42:40

but it must be at least twice as big as the beetle, a really huge grub.

0:42:400:42:46

Beetles and many other insects spend so much of their lives as flightless larvae

0:42:460:42:50

that it would be more accurate to think of them as creatures of the earth rather than the sky.

0:42:500:42:56

Flight for them, as it is for the mayflies,

0:42:560:42:58

is a relatively brief episode at the end of their lives.

0:42:580:43:03

These cicadas in the eastern United States, spend 17 whole years below ground,

0:43:030:43:08

sucking sap from tree roots.

0:43:080:43:11

And then, within a few days, a whole population emerges.

0:43:110:43:15

There may be millions of them in a single acre of land.

0:43:300:43:34

They clamber up the trees whose roots have provided them with sap for all of those 17 years.

0:43:430:43:50

And here they change into their adult costume.

0:44:060:44:10

Now they have the wings they need to search for a partner.

0:44:340:44:39

Empty larval cases cover the tree trunks and the ground beneath.

0:44:430:44:47

And above, in the branches, the millions have started to sing.

0:44:520:44:57

The noise is ear-splitting.

0:44:570:44:59

HIGH-PITCHED SCREECHING

0:44:590:45:03

After 17 years of living underground,

0:45:150:45:18

the cicadas are now approaching the climax of their lives.

0:45:180:45:23

And for the males, that means this.

0:45:230:45:27

The call is his way of attracting a female.

0:45:320:45:36

The females reply with a quite different sound.

0:45:440:45:48

A click made by flicking her wings.

0:45:500:45:55

That's what the males are listening out for.

0:45:550:45:58

I can imitate the female's wing flick with a snap of my fingers...

0:45:580:46:04

and that causes them to follow me anywhere,

0:46:040:46:07

because they are so determined to find a female.

0:46:070:46:11

Now I can bring you back?

0:46:260:46:28

How about coming this way?

0:46:320:46:35

Oh! The noise is awful.

0:46:430:46:46

Come this way.

0:46:460:46:49

Yes, I can hear you.

0:46:490:46:52

Quite right.

0:46:550:46:56

At last, a male finds his partner

0:46:580:47:01

and as he does so, his call alters.

0:47:010:47:04

He is indicating to her that, after 17 years,

0:47:060:47:11

the time has come to get down to business.

0:47:110:47:15

How do these cicadas all emerge simultaneously after 17 long years?

0:47:300:47:37

Well, we know they can appreciate changes in the content of tree sap,

0:47:370:47:43

so they are able to detect the passing of a year.

0:47:430:47:46

But how do they count up to 17?

0:47:460:47:49

We have no idea.

0:47:490:47:51

But even if we did, this surely would remain

0:47:510:47:55

one of the most astonishing, amazing events in the insect world

0:47:550:47:59

and it will all be over in a couple of weeks for another 17 years.

0:47:590:48:06

In the next programme of Life In The Undergrowth,

0:48:270:48:30

we tell the story of a substance that completely revolutionised the lives of invertebrates - silk.

0:48:300:48:38

Many different creatures use this wonderful material,

0:48:420:48:46

but you can't tell the story of silk without the silk masters - spiders.

0:48:460:48:51

And for some people that's a bit of a problem.

0:48:540:48:59

A lot of us find spiders really rather upsetting.

0:48:590:49:04

Why that should be is not clear to me.

0:49:040:49:06

Perhaps it's because they've got eight legs

0:49:060:49:10

and move in a most unpredictable way, and what's more move very fast.

0:49:100:49:14

But whatever the reason is, a lot of people do hate spiders.

0:49:140:49:19

But if you can once overcome that dislike

0:49:190:49:23

then you look at the animal as an animal with problems to solve -

0:49:230:49:28

how to find its mate, how to find food,

0:49:280:49:31

how it constructs these elaborate webs,

0:49:310:49:34

which must be among the most extraordinary constructions in the whole of the animal world.

0:49:340:49:40

Once you can do that, you see how absolutely astonishing they are.

0:49:400:49:44

And that was the key challenge for the next episode -

0:49:440:49:48

to see beyond our fear and uncover the fascinating way in which spiders use silk.

0:49:480:49:56

And where better to start than with the Australian redback.

0:49:560:50:02

This is one of the world's most notorious spider.

0:50:020:50:05

Do you get many redback bites?

0:50:050:50:09

-Somewhere between 500 and 1,000 bites every year.

-But you don't die from it?

-Well, people have died,

0:50:090:50:15

-but this is a slow-acting venom. It might take five days for someone to die from it.

-So you've got time?

0:50:150:50:22

'Warwick Angus is an expert on redback webs, and he's convinced

0:50:220:50:28

'that if you treat these spiders with respect there's no need to fear them.'

0:50:280:50:33

They're not aggressive, they're the opposite, they're defensive. But they're so placid.

0:50:330:50:39

There she is, showing no signs of aggression. But that's her home,

0:50:390:50:43

and if we pick up the plant pot, we're destroying her home and she can't talk...she can only bite!

0:50:430:50:50

Encouraged by Warrick,

0:50:500:50:52

I can put my caution aside and focus on the complex web

0:50:520:50:56

she has built under the plant pot, which we were there to film.

0:50:560:51:00

You might think it's just a cobweb, but in fact it's a very subtle construction. There is a dome...

0:51:000:51:06

over the top part and, from the dome, there are a lot of vertical threads which go down to the ground.

0:51:060:51:13

An ant crawling along the bottom of this decking,

0:51:130:51:17

if it touches one of these vertical strands, the strand breaks

0:51:170:51:23

and whips up the ant and then the spider can catch it.

0:51:230:51:27

When you can see all this, you gain a whole new appreciation for this creature.

0:51:270:51:33

And there's an encouraging twist to Warrick's story.

0:51:330:51:36

What made you first get involved in spiders?

0:51:360:51:39

I mean, spiders are your life now.

0:51:390:51:41

-I used to be arachnophobic.

-Really? You mean you actually hated spiders?

0:51:410:51:47

I couldn't go in the room if there was a spider. I had to run outside, I couldn't handle it.

0:51:470:51:53

But once I started to try and get over the fear,

0:51:530:51:57

that fear led to a fascination, that fascination just grew and grew.

0:51:570:52:02

From arachnophobe to expert. There's hope for us all.

0:52:020:52:06

And it doesn't end there.

0:52:080:52:11

In Malaysia, cameraman Gavin Thurston is looking for another spider which we wanted to film -

0:52:110:52:17

the trapdoor spider.

0:52:170:52:19

He's had a similar discovery about the expert he's working with - Stephen Hogg.

0:52:200:52:25

Just an interesting point Stephen was just telling me.

0:52:250:52:29

Stephen's our spider expert, but he's actually afraid of spiders!

0:52:290:52:34

Well, since childhood I'm terrified of them!

0:52:340:52:38

It makes my heart beat, they terrify me.

0:52:380:52:41

And just like Warrick and his Redbacks, Stephen's fear of spiders has somehow led to a fascination.

0:52:410:52:48

..Will walk along the lines of silk.

0:52:480:52:51

The spider detects this and lunges out and grabs its prey.

0:52:510:52:55

That night, Stephen and Gavin return to film this nocturnal spider in its burrow

0:52:570:53:03

with the help of a chip on the tip camera -

0:53:030:53:05

a remote controlled probe with a tiny camera and light on the end.

0:53:050:53:10

As Gavin carefully feeds the probe into the spider's burrow, Stephen can watch from a distance.

0:53:120:53:19

Unlike Warwick he hasn't quite got over his arachnophobia.

0:53:190:53:22

That's it...hold it. That's good.

0:53:220:53:25

Though that's hardly surprising when you get a close look at this spider - hairy legs, huge fangs.

0:53:250:53:32

But with this probe, he can see beyond all that.

0:53:340:53:38

And for the very first time, we can film the detail of this spider's remarkable trap.

0:53:400:53:46

An ingenious silk collar connected to the external tripwires keep the spider's feet

0:53:480:53:53

constantly in touch with the outside world, ready to pounce.

0:53:530:53:58

Another night, another spider. This time, not quite so scary -

0:54:030:54:08

the bolas spider.

0:54:080:54:10

It's also nocturnal...

0:54:120:54:14

and is very sensitive to light.

0:54:140:54:17

So we have to approach it very carefully under red light at first.

0:54:170:54:20

Then when it is comfortable with our cameras, we wait...

0:54:200:54:24

Here's its prey.

0:54:280:54:29

Once it's locked onto the moth, it won't mind the light.

0:54:310:54:35

Its weapon -

0:54:490:54:51

a single strand of silk with a drop of glue on the end.

0:54:510:54:55

The more we look at spiders, the more fascinating they become.

0:54:570:55:02

You can't help your jaw sagging just a little and saying,

0:55:020:55:06

my goodness how absolutely extraordinary that they can behave

0:55:060:55:11

in this complicated and seemingly intelligent way,

0:55:110:55:14

when they are the size they are with the number of brain cells they must have tucked away

0:55:140:55:20

in a little tiny invisible point in the middle of that head.

0:55:200:55:28

Amazing.

0:55:280:55:30

But to really understand spiders, you have to completely immerse yourself in their world.

0:55:340:55:42

Tim Shepherd spent a total of 200 hours filming a spider that you can commonly find in your garden -

0:55:430:55:49

a wolf spider.

0:55:490:55:51

They really are little. Their leg span is probably the width of your little finger nail.

0:55:510:55:57

When you start to see them under really big macro lenses,

0:55:570:56:01

you go into a completely different world

0:56:010:56:05

and you start to, after a while,

0:56:050:56:07

begin to get a feel of what it might be like to be a spider

0:56:070:56:11

and to walk past a piece of moss that's actually like a tree trunk.

0:56:110:56:15

It's nearly impossible to film a spider this small in the wild

0:56:170:56:22

but, because it's so tiny,

0:56:220:56:24

Tim can easily create a complete habitat for it in a studio

0:56:240:56:28

in which it will be quite at home.

0:56:280:56:31

Filming these wolf spiders has revealed

0:56:310:56:35

a whole array of behaviour

0:56:350:56:38

from the superb little courtship behaviours that the males do,

0:56:380:56:42

through to the female making this incredible little egg pouch -

0:56:420:56:47

it's a structure that's intricate and beautiful -

0:56:470:56:51

and then she carries it around and looks after the babies when they hatch.

0:56:510:56:56

So she's got this wonderful maternal care to her character.

0:56:560:57:01

So all these different things help to make spiders much more interesting

0:57:010:57:07

than a big scary creature that's about to bite you.

0:57:070:57:10

But that's not to say that some spiders aren't big and scary.

0:57:100:57:15

In Australia, Warrick is proof that no-one's immune from arachnophobia,

0:57:150:57:19

and he's determined to convince everyone that it's something well worth getting over,

0:57:190:57:24

with Incy Wincy, his big, hairy and venomous bird eating spider.

0:57:240:57:30

Go on, David, have a cuddle.

0:57:300:57:33

-Oh...

-OTHERS LAUGH

0:57:330:57:35

If there are many reasons to dislike spiders,

0:57:360:57:41

then Incy Wincy encapsulates all of them.

0:57:410:57:45

However, knowing that she was no threat to me as long as I was no threat to her, reassured me.

0:57:470:57:53

We had an understanding.

0:57:530:57:54

Just two creatures trying to solve life's problems.

0:57:540:57:57

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0:58:330:58:36

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