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00:00Planet Earth 300 million years ago.
00:18A world of lush green forests.
00:21Sanctuary for creatures gaining a foothold on land.
00:28But within this ancient habitat, a colony of insects already hummed with life.
00:42Insects were the first airborne creatures.
00:49In their early days, giant dragonflies with wingspans of nearly three feet dominated the skies.
00:58Insects of myriad designs were evolving.
01:10Stenodictia looks a lot like the present day dragonfly.
01:16Protophasma bears an uncanny resemblance to today's cockroaches.
01:32With strikingly different anatomies, our amphibian ancestors were also making their way onto land.
01:44Over the ages, amphibians would give birth to dinosaurs, mammals, and a host of other animals.
01:53But insects, more than any other creature, would succeed at populating the face of planet Earth.
02:02This is a new wood and a planet Earth.
02:12D summery is so absolutely familiar with, but it would beba two.
02:17There is a new wood and alderoo in the body.
02:21ORGAN PLAYS
02:51ORGAN PLAYS
03:20150 million years ago, Earth's land vertebrates had made remarkable progress.
03:26Berosaurus, a giant that ruled Jurassic forests throughout most of the dinosaur era.
03:41This animal was as tall as a five-story building and stretched more than 80 feet from end to end.
03:49In the years following their arrival on land, dinosaurs diversified, ultimately penetrating every ecosystem across the globe.
04:03At the height of their hundred-million-year reign on Earth, dinosaurs were a model of evolutionary success.
04:13This dragonfly fossil from the dinosaur era is only a fraction the size of its ancestors.
04:25Faced with numerous predators, insects reversed earlier survival strategies, growing smaller as time passed.
04:35Without a backbone, vertebrates like the dinosaur could never have grown to their gargantuan size.
04:49A sturdy spine could support a larger body.
04:56Insects have no internal structural support, just a kind of body armor, a skeleton worn on the outside.
05:12If this beetle could grow as large as some vertebrates, this anatomical design would spell disaster.
05:22With its carapace of shell now stretched thin, the inner body sags and eventually collapses.
05:30If its exoskeleton were thickened to support a giant body, the beetle would fare no better.
05:39To hold the beetle's weight, the shell would have to be very thick.
05:43So thick that there would be no space left for muscles and organs.
05:48Exoskeletons were an evolutionary innovation, but they had their limitations.
05:55Size was only one adaptation.
05:59Insects tested other survival strategies, developing special organs for their streamlined bodies.
06:09One major achievement, the compound eye.
06:17The compound eye is an assembly of as many as 25,000 tiny lenses.
06:25Each of these hexagons is the lens of an individual eye.
06:37Viewed in cross-section, the compound eye appears very thin, like a layer of film.
06:47Two thousand of these lenses together occupy only one tiny square millimeter of space.
07:01This is an artificial compound eye, designed to simulate an insect's vision.
07:11A plate with 2,000 lenses is placed in front of a camera.
07:17Although less precise than the average human's eyesight, insect vision is sharp enough to discern the shape of these flowers.
07:27This unique adaptation gives dragonflies an advantage, which would be passed on to other insects.
07:33In Earth's evolutionary drama, who or what survives or vanishes to extinction is unpredictable.
07:51The rise of flowering plants, or angiosperms, spelled the end of the dinosaur era,
08:01and a new age for insects and mammals that flourished in their midst.
08:11In his outdoor laboratory, Cornell University biologist Dr. Carl Nicholas observes nature's age-old alliances at work.
08:21To ensure their survival, Nicholas says that early plants and insects formed highly specialized relationships.
08:29Insect pollination allows a plant to transport pollen from one individual to the next,
08:35using the brain of the insect to identify the same kind of plant as the donor of the pollen.
08:42So, for example, you can have angiosperms that are separated by many miles.
08:46Two flowering plants of the same species separated by many miles,
08:50and the insect can transport pollen over that mileage.
08:53Plants can't move, but insects can.
08:57Through the act of pollination, insects and flowers became partners in evolution,
09:02helping each other to survive and prosper.
09:07Flowering plants reward insects with nectar, or pollen, providing a sensory roadmap to the source.
09:17During the Cretaceous, for the very first time, there was a partnership that was established between flowering plants and insects.
09:24Before that time, it was an antagonistic relationship. The insects were eating the plants.
09:30But with the evolution of flowering plants, a kind of hand-and-glove relationship began to evolve.
09:37Flowers started changing their reproductive structures to accommodate the insects that were visiting them.
09:43And insects were beginning to change their morphology, their shape, to accommodate the visiting of flowers.
09:52The most sophisticated adaptation was undoubtedly the compound eye.
09:56Unlike humankind, insects can see colors in ultraviolet light.
10:11Observed through a special camera that simulates insects' vision, flowers look different than they do to our naked eye.
10:19Like neon roadsides, the vivid centers beckon, each plant favoring specific insects.
10:29Through one-on-one relationships, both insects and flowers prospered.
10:36By the end of the dinosaur era, scientists believed that the diversity of insects was almost complete,
10:48with the number of species nearing present-day levels.
10:51A weevil, less than half an inch long.
11:04Its long trunk searching for pollen looks like that of a miniature elephant.
11:1060,000 different species of weevil exist today.
11:22Remaining small and adapting to a variety of habitats and food sources, insects are masters of survival.
11:29Across the globe, they have prospered for millions of years, unlike any other living creature.
11:45Evidence of nature's partnerships abounds in fossil records around the world.
11:50Where bonds are strong, the odds of mutual survival improve.
12:00The suburbs of Frankfurt am Main, Germany.
12:0350 million years ago, this area was a lake surrounded by a dense forest.
12:12From time to time, lethal volcanic gas erupted from these waters.
12:20Annihilated by the vapors, animals that walked or swam or flew were buried here millions of years ago,
12:33enveloped in an earthen time capsule.
12:38This beetle fossil scintillates a beautiful metallic blue.
12:43This is an ancient jewel beetle.
12:46The exceptional conditions of this lake bed preserved the beetle's exquisite natural color.
12:53This stag beetle also maintains a distinctive shape, as if it were still alive.
13:01Altogether, 400 species of insects were found here in the Messel oil pit.
13:08Alongside the insects, a number of mammal fossils were excavated.
13:19Proof that in the wake of the dinosaur, Earth's evolutionary path had taken a new turn.
13:29From these shadowy remains emerges the shape of a head.
13:42It's a bat, the most frequently sighted animal here.
13:45The theory is that bats flying over the lake succumbed to poisonous gas eruptions and fell to their watery tomb.
13:57So sudden were their deaths that even the stomachs became fossilized.
14:07This compound eye was found in the digestive tract of a fossilized bat.
14:16It had been feeding on insects.
14:20Scales from the bodies of moths also surfaced in these specimens.
14:29From the samples found at Messel came evidence that surprised biologists.
14:35Moths made up to 70% of the bat's diet.
14:38To escape the notice of predatory birds during daylight hours, moths, over time, lived on the night shift.
14:56Today, more than 200,000 species of moths exist on the planet.
15:02They are the most successful of the nocturnal insects.
15:08Bats have been nocturnal animals for more than 50 million years.
15:24Most modern day bats still prey on moths.
15:28Confining themselves in caves and crevices during the day,
15:32they emerge at sundown in search of prey.
15:38Bats fly in the dark with the help of ultrasound, inaudible to human ears.
15:49A specially devised microphone picks up the ultrasound emitted by the bats.
15:55Relying on ultrasound to see obstacles and prey, bats fly freely through the night forest.
16:05The bat's peculiar nose serves as a satellite dish emitting ultrasound.
16:08A huge pair of ears may equal half the size of the bat's head.
16:12Inside the ear is a snail-shaped organ.
16:13This highly sensitive device can detect even the slightest amount of noise.
16:14The bat's peculiar nose serves as a satellite dish emitting ultrasound.
16:20A huge pair of ears may equal half the size of the bat's head.
16:26Inside the ear is a snail-shaped organ.
16:38This highly sensitive device can detect even the slightest ultrasound echo.
16:43A tremendous amount of information captured by the ears gathers in the brain.
16:51A breakdown of the sensory data provides the bat with an image of its surroundings,
16:56as if it could actually see.
16:58The bat releases various types of ultrasound to trap moths.
17:09First, it emits ultrasound in search mode, scanning for signs of the moth.
17:19Detecting the precise shape, location, and speed of its intended victim,
17:24the bat can swoop in for the kill like a laser-guided missile.
17:33With survival skills honed over millions of years, bats are master predators.
17:47The University of Toronto, Canada.
17:49It is here that zoologist Dr. James Fullard studies the defense mechanisms of the moth.
17:56He now knows that moths have a specially developed organ designed to help them evade bats.
18:05Moths were flying at night and didn't have ears before the bats arrived.
18:10And once bats began to fly, once bats began to send out their sonar signals,
18:14then the moths had to come up with some way in which to detect the bats.
18:19And what moths did was change a very sensitive sense organ on the base of one of their wings
18:25that was already there that was telling the moth what the position of their wings were.
18:30And because it was already a sensitive organ, that organ became what we call pre-adapted,
18:34or it became more likely to turn into this particular organ.
18:38In this case, what happened was it became an ear.
18:40Directly below the moth's wings lies a small hole.
18:47Within is the tympanic membrane, a kind of eardrum.
18:51Further inside this ear are the two cells that catch the bat's ultrasound.
18:57How can moths fend off attack using only this rudimentary system?
19:03The moth knows that the bat is getting very close because it can hear that sound with its ears.
19:10The bat sounds closer because it's louder.
19:13And the bat is also putting out a kind of sonar which is specific to being very close.
19:18So the moth has that information, it knows.
19:20It can't see, of course, this is all happening at night, but it knows by its ears where the bat is.
19:23And it also can tell which side the bat is coming from because it has two ears.
19:28It has an ear on this side, it has an ear on that side.
19:31And by determining which side the bat is coming from, it can make a correct movement away.
19:36Dr. Fullard has been working with tape recordings of a bat's ultrasound to determine how moths might escape these predators.
19:49This is the same ultrasound bats use in tracking mode.
19:59The moment the ultrasound begins, the moth responds by flapping furiously.
20:04Eventually ceasing its struggle to escape.
20:09The experiment shows that with only two cells activated, the moth is extremely sensitive.
20:16Immediately picking up the bat's ultrasound, the moth reacts quickly, increasing its chances of survival.
20:24Some moths will just fold their wings up and drop straight to the ground.
20:28And that is hopefully to get away from the bat because the bat will be swooping like that.
20:35There's another way of getting away from the bat though, which is exactly the opposite, and that's to actually fly up.
20:40Because what the bat is doing is coming down like this, the moth flies up.
20:44The bat, because it's heavier, can't adjust its flight in time and so misses the moth as it goes underneath.
20:49Free-flying moths were exposed to the same tape recordings.
20:57The instant the ultrasound stimulates the moth, it appears to fall toward the ground.
21:05Tracked in stop motion, the moth actually turns around and quickly nose-dives.
21:14In the nick of time, the moth escapes the simulated bat.
21:21With its attacker only a few feet away, the moth vanishes from the bat's radar.
21:26The insects that have lived the longest in the world are the ones that have got the simplest nervous systems.
21:36You just can't count nerve cells and say that some animals are better than other animals.
21:40Animals are evolved into their, into what they have to do in life.
21:44And evolution allows them to do that.
21:46And evolution doesn't make any judgements.
21:48It doesn't say this animal's better than that animal.
21:50It lets the animals decide who's better than that.
21:52And the, the successful ones survive and the, and the unsuccessful ones don't.
22:00Over millions of years, the slow accumulation of simple adaptations has made insects a diverse and resilient group.
22:13In the tropics of Asia, swallow-tailed butterflies have honed one of nature's most brilliant survival strategies.
22:22Cleverly hidden in the branches of this tree is the pupa of a swallow-tail.
22:31It is camouflaged green to blend in with the foliage.
22:41Here, the pupa of the same species is brown.
22:43To protect themselves from their chief predator, the bird, swallow-tailed pupae adjust their color to match their surroundings.
22:53What actually determines the color of the swallow-tailed pupae?
22:59Dr. Kehichi Honda of the University of Hiroshima, Japan speculates that the answer lies in the texture of the branches.
23:09He prepares two wires.
23:13One is green, but rough.
23:15The other, brown, but smooth.
23:17These conditions reverse the natural order.
23:21How will the larvae adjust?
23:24The insects can barely see.
23:34Instead, they feel the surface of the wire as they inch along.
23:43Choosing a safe place to transform into moths is their last act as larvae.
23:47Within a few days, the pupa on the rough wire turns brown.
24:05The one on the smooth wire is sheathed in green.
24:13Relying on touch instead of vision, the larvae adjust their color.
24:21Insects can't see the detailed features of different parts of a tree.
24:26Their behavior is based on very limited sources of information.
24:36In nature, a smooth surface means a green branch.
24:42A rough surface, a brown one.
24:45A simple but critical concept for survival.
25:04Some insects mimic even the most delicate textures of leaves.
25:07The elaborate technique of camouflage is truly astounding.
25:17And remains, to this day, one of the great natural defenses.
25:24Responding to nuances of their environment,
25:28these tiny insects have survived the ages,
25:32while entire families of vertebrates became extinct.
25:35In the woods of suburban Tokyo, a model cooperative thrives.
25:51Once independent operators, insects long ago discovered
25:55that collective living could work more efficiently.
25:58In the woods of northern Tokyo,
26:02these are Japanese honeybees.
26:05By some standards, one of nature's most complex insect societies.
26:15In this colony, 10,000 honeybees make up one society.
26:19It is a strict caste system that maintains clear division of labor.
26:24Some bees forage, while others build nests or store honey.
26:32The hive functions smoothly without a leader,
26:38because the bees act in concert.
26:41This social behavior is the secret of their success.
26:44In wooded areas across Japan, the honeybees find sanctuary.
27:06But there are times when the atmosphere changes,
27:10and this quiet haven becomes a battleground.
27:13A wasp tries to attack the honeybees flying in and out of the nest.
27:19Hearing the vibrating wings of the enemy wasp,
27:27the honeybees perform a war dance,
27:30shaking their bodies and fluttering their wings in a threatening gesture.
27:33In response, the wasp attempts a sneak attack on the honeybee nest.
27:42The wasp is several times larger than the bees.
27:47But the honeybees are fiercely territorial.
28:03One after another, they fall upon the invader,
28:07eventually covering him completely.
28:09A look through a special heat-sensitive camera
28:24reveals that the swarm of bees engulfing the wasp
28:28is getting warmer and warmer.
28:33Vibrating the muscles of their wings,
28:35the honeybees are cooking the wasp.
28:41When the temperature reaches 113 degrees Fahrenheit,
28:46the wasp dies.
28:50The honeybees can generate more heat,
28:53but are careful not to let the temperature climb any higher.
28:56At 118 degrees, they too could risk death.
28:59This skillful defense allows bees to take on enemies larger than they are.
29:15Inside the hive, the entire colony is creating a wave of sound.
29:33Like a squadron of fighter planes,
29:36these insects are delivering a powerful display to their enemies.
29:39Professor Masami Sasaki of Tokyo's Tamagawa University
29:59is studying how the bees communicate the location of pollen and nectar.
30:03First, he places an artificial feeder about 100 yards from the colony.
30:18A solution of sugar water at the edge of the feeder rewards visiting bees.
30:23The first bee to visit the feeder is marked with blue.
30:30Scientists and other honeybees will watch it closely when it returns to the colony.
30:37Back in the hive, the bee spins around as if dancing.
31:01Those observing its gyrations will be marked with orange.
31:04Soon, the bees dotted in orange will leave the colony.
31:09One by one, they head straight for the artificial feeder.
31:25All of the bees find their way.
31:28How did they know where to look?
31:30Somehow, the location of this feeder was announced to the hive by the bee marked in blue.
31:47Scientists like Professor Sasaki believe that honeybees use the sound of their wings to communicate.
31:53But what kind of information is being transmitted by the wings' vibration?
32:00Professor Sasaki's group makes field recordings of the bees to bring back to the lab for an analysis.
32:16When the honeybees shimmy, Sasaki says the sound produced indicates distance from the colony to the potential food source.
32:31We think that the honeybees receiving information from a member of the colony wave their antennae over the dancing bee like this.
32:37They recognize the sound vibrations resonating through the antennae, and then fly off to the flowers.
32:51Sometimes we place the feeder a few feet from the colony, sometimes half a mile away.
32:55The returning honeybees dance.
32:59We learn that if they dance for one second, it means that the food source is about 2,200 feet away,
33:05and that's what they're communicating to the others.
33:10Upon closer observation, the dance is more complex than it looks.
33:14The honeybee will always face the same direction when it shimmies, generating sound.
33:29Using only body language, the bee gives precise directions to the nectar.
33:34The hive stands perpendicular to the ground.
33:42When the bee gyrates, it too is vertical.
33:46The line of the hive and the direction of the dance create an angle, as illustrated by this diagram.
33:53By shifting the line to the position of the sun, scientists discovered that the gyrating bee points directly to the food source.
34:05As the dawn breaks and flowers stretch to greet the sun, the colony hums with activity.
34:26A message delivered by a single bee reverberates throughout the hive.
34:35Acting collectively, these simple creatures have forged communities that have withstood environmental pressures.
34:56Throughout the ages, specialization has ensured the bees' survival.
35:00In the world of insects, bees were not alone in developing complex societies.
35:24Sealed in a capsule of amber, this ant and larva have been frozen for 20 million years.
35:30Where were they headed when time suddenly stopped?
35:45Suspended in this tiny two-inch square is the rest of its colony, in all 2,000 ants.
35:53Ants are the minimalists of the insect world, with no physical frills.
36:00They look similar to bees, but have no wings.
36:05Their vision is poor.
36:08Yet they have developed an even more sophisticated social structure than bees.
36:12At the Brussels Free University, researchers are attempting to understand how these complex societies work.
36:25In his laboratory, Professor Jean-Louis de Neubourg is studying the way ants interact within the colony, using simple logic-based mechanical models.
36:40Ants are in the habit of collecting scattered objects.
36:44Ants are in the habit of collecting scattered objects.
36:47De Neubourg is observing the insects to find out what determines their behavior.
36:52His research has led him to conclude that individual ants are hard-wired by nature to follow a simple set of rules.
37:06Using tiny ant-like robots, De Neubourg tests his theories.
37:15He gives them easy logic instructions.
37:18The rest is left to chance.
37:20If there is a peg in front of the robot, it will pick it up and carry it.
37:26If it runs into another peg, it will set it down and turn in a random direction.
37:33Over time, a significant pattern appears, even though the robots operate independently of one another.
37:40This small-scale model illustrates how ants acting as simple individuals can produce a collective result.
37:58From models like this one have come insights into the nature of intelligence and the functioning of insect societies.
38:06It is clear that there is no headquarter or leader and that there is no centralized system as we know for humans.
38:18But what self-organization teaches us is that the rules needed to produce such a global response, such a well-defined pattern, are generally more simple.
38:29They are not as complex as specialists looking at social insects believe these rules must be.
38:43Baro, Colorado Island, a small slice of tropical rainforest on the Panama Canal.
38:48Professor de Newburgh's team has come to study a species of ant that for millions of years has thrived in jungles throughout the Americas.
39:06The leaf cutters.
39:07On a network of highways, they trampled through the forest.
39:12They speed along in convoys, sometimes several hundred yards long.
39:18These tiny insects have fared exceptionally well in the evolutionary chain.
39:24Studying their behavioral patterns, the scientists are trying to understand the secrets of their success.
39:31In rainforests like this one, leaf cutter ants clear more vegetation than any other living creatures.
39:42Unlike most other kinds of ants, leaf cutters can digest fresh foliage.
39:48Using its long legs as a compass, a leaf cutter measures a neat crescent.
39:56Its sharp mandibles trim the leaf as efficiently as scissors.
40:13The harvesting continues night and day.
40:17A colony of leaf cutters will collect close to a ton of foliage this way every year.
40:23Carrying leaf fragments many times their own weight, the ants cover long distances at dizzying speeds.
40:34Efficient grazers, they forage selectively, moving frequently from plant to plant.
40:41When a fallen leaf barricades their root, the obstacle is promptly removed.
41:00Eons of experience have made them efficient foresters.
41:05Like all ants, leaf cutters are a society of females, born of the same queen.
41:18Only the largest do the heavy lifting in the forest.
41:23The ants live in huge colonies, sometimes five million strong.
41:33One of the oldest agricultural societies on earth, each member has duties to perform.
41:42Their job, determined by their size.
41:44Inside the nest, mid-sized ants pick up the relay, tearing the leaves into smaller pieces.
41:57Another cast chews the leaf fragments into pulp, adding fecal fluid as fertilizer.
42:03The smallest ants in the colony apply the paste to the nest walls, which will then be mixed with fungus from older chambers.
42:13Others weed and harvest.
42:16Soon, the small white puffs will spread across the nest, enough to feed the entire colony.
42:22These fungi are the mainstay of their diet.
42:27Working their subterranean plots, leaf cutters are the only fungus-growing ants to use live plants in their farming.
42:40Agriculture was a way of life for these insects millions of years before humans appeared on the planet.
42:46I don't know why such insects stimulate me so much.
42:56It's possible that it's a little bit because it's like another planet.
43:04Because we are human and function within a certain system, we think of old behavior in terms of our logic, our rules.
43:12But it's an entirely different situation in the insect world.
43:19Here, I have in front of me something that is stronger and more original than any science fiction books that I have ever read in my life.
43:37It is morning in the forest.
43:42It is morning in the forest.
43:45Rush hour is already underway.
43:51Filing through the branches like obedient motorists, these ants are cleaning house after the harvest.
43:59It's time to make room for another crop.
44:01The ants pile the refuse in one place, their own compost heap.
44:21The mountain of discarded leaves will eventually return to the soil to provide rich fertilizer for the forest.
44:30For 300 million years, insects have held fast to successful survival strategies.
44:45By responding to evolutionary pressures, modifying their size, and becoming masters of camouflage, their communities continue to thrive.
44:59Today, insects account for at least 70% of the animal species on earth.
45:06In the lottery of life, they have outmaneuvered the dinosaur, and a host of other creatures, great and small.
45:14At home, in every ecosystem of the planet, their luck shows no sign of running out.
45:22Perhaps humans can learn from the eloquent simplicity of insects, as we answer environmental challenges of our own.
45:34of our own.
45:35of our own.
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