In the kingdom of animals, one class of creatures stands out.
We once thought of them as the little things underfoot.
Now we're beginning to see they are more than just biological curiosities.
They were an ancient lineage when the dinosaurs appeared.
Today three of every four species of animal is an insect.
A billion, billion are alive right now.
It's not an exaggeration to say that they are the little things that run the world.
Of all classes of animals, insects are the most successful.
It's been said that insects shall inherit the earth.
The truth is they own it now.
Scientists are piecing together the story of their success.
Behind this buzzing confusion is an orderly society.
How do tens of thousands live as one?
An insect may be worth its weight in gold.
Could a chemical defense cure disease?
The common moth is a marvel of aerodynamics, but how it stays aloft remains a mystery.
What can be learned from the first creatures to fly?
We share the planet with a remarkable group of animals.
No other form of life can match their abundance and diversity.
They dominate our world.
They are the ruling class.
The Infinite Voyage is made possible by a grant from Digital Equipment Corporation through
its Digital Discovery Series, celebrating the arts, sciences, and humanities.
Digital and its employees invite you to join with them in supporting public television.
Like many children, Seth Bensel can discover an entire world in a patch of grass.
Seth is a predator of the small.
His particular fascination is insects.
At the age of 11, Seth is already something of an expert, but he doesn't live in the country
or even in the suburbs, he lives in New York City, and he shares the interests of urban
kids everywhere.
For Seth and his friends, video games and comic book heroes have an irresistible appeal.
But in Seth's own backyard in Brooklyn, there's a realm of creatures far more exotic than
teenage mutant ninja turtles.
I first became interested in insects when we lived in Washington D.C., and my dad and
I used to go around Glover Park and parking lots and stuff looking for car parts and gears
and spark plugs and stuff.
And one day we couldn't find any, so we decided to go into the park.
And we overturned some rotten logs by a swamp and got a grub and a post beetle.
So we took them home and put them in a big terrarium.
And we filled it with dirt and planted some plants in there.
And that's really how I got interested in them.
And the difference between them and car parts is just that, well, they move and they eat
and they live.
Seth's curiosity has developed into a passion.
To pursue it in a place like Brooklyn, sometimes you need a little help.
In this case, it comes in the form of a delivery.
His mother has drawn the line at bees, cockroaches, and tarantulas, but fruit flies are no problem.
The flies are a meal for his praying mantises.
What attracts Seth to the mantises is the same thing that draws his friends to science
fiction heroes.
They are like creatures from another world.
My favorite insect is the praying mantis because I like the way it moves and the way it just
sits and waits for other insects to come by.
I also like the way its face looks so wise and like sort of wistful.
And also like the shape of its body and what it does.
Sort of like a robot just programmed to hunt and kill.
All insects have six legs, spiders have eight, which is one reason they're not insects.
All insects have a body divided into three different parts, the head, the thorax, and
the abdomen.
The head is in front, the thorax is between the head and the abdomen, and the abdomen
is the last segment.
So most insects have two pairs of wings, and all insects have to have a pair of antennae,
which look sort of like legs, except they're jointed in more places and they're used for
smelling and feeling.
Nearly one million species of insects are known to science, a million variations on
one fundamental body plan.
Tom Eisner is a biologist at Cornell University in Ithaca, New York.
He and Seth became pen pals after Seth wrote him about his science project.
Now Seth comes here every summer for camp and for a chance to spend time with his mentor.
Eisner is a world expert on insects.
When I see a new insect, the first thing that comes to mind is that there must be lots of
things that it's got up its little sleeves that we don't know.
I mean, in another way I look at it as a feeding machine, as a breeding machine, as a real
success story in evolution.
I mean, insects are members of the ruling class, and every single one of them obviously
has a success story hidden in it.
For most of us, a cockroach inspires only one thing, revulsion.
But for those with the patience to study them, cockroaches can be a source of wonder.
Try not to get them crawling on your arm, because the first thing they'll do is try
to hide in your sleeves.
You've got all stages here.
These give birth to living young, just like mammals.
They have litters.
They don't lay eggs.
You've got males and females.
The males and females have the wings.
Like Seth, Eisner was intrigued by insects at a young age.
But unlike Seth, Eisner's curiosity used to hurt his standing in the neighborhood.
Well I grew up in South America and this wasn't a very male thing to do, to collect insects.
So when I told people that I collected insects, I always got some peculiar follow-up questions.
So I hit upon the experience of saying that I'm collecting insects because I use them
for bait to fish.
That was macho.
That was all right.
Watch carefully.
I'm going to make believe that I'm an ant and that I'm going to attack this cockroach.
I'm going to give him a very gentle bite on one leg.
Whoa.
Impressive.
Take the forceps and just gently...
This cockroach, equipped with a noxious spray, is prepared for chemical warfare.
Grab the leg a little higher up.
Look at that.
See it?
Put it back in the cage because it's already served its purpose.
There it is.
Back it goes.
Things that creep and crawl delight the young.
And for those who stay captivated, the world of insects offers vast rewards.
The Natural History Museum in London is home to the most comprehensive collection of insects
in the world.
In these drawers alone are the spoils of one man's passion.
For two million butterflies and moths.
To some, they are a feast for the intellect.
To others, a feast for the eyes.
This is the bounty of a tireless collector.
His name was Walter Rothschild.
Born in England in 1868, Rothschild's livelihood was banking, the family business, but his
life was animals.
The more exotic, the better.
The last of the great collectors, he had money to support his tastes, but he was hardly a
member of the leisure class.
He financed expeditions around the world and described more than 5,000 new species of animals.
Collecting ran in the family.
His brother, Charles, was an expert on fleas.
His collection resides in the same museum.
The Rothschild tradition is carried on by Charles' daughter, Miriam.
My father was a very good biologist and he taught me really all I know.
From the age of four, I just liked insects.
I used to collect ladybirds and I hated dolls or anything that wasn't alive.
It really was very easy for me to get into natural history, almost like a profession.
Now in her 80s, Miriam Rothschild lives at the family estate in Ashton, England.
A prolific scientist in her own right, she has long been intrigued by the relationships
between insects and plants.
But fleas were her first scientific love.
She began her career with the painstaking work of distinguishing one insect from another.
If you had to tell the difference between a cat and a dog, at first sight it would be
very easy, but when you come down to describing details, how are you going to do it?
And you realize then that it's not so easy.
You're telling one flea from another, you have to be a specialist, but it's really important.
And a specialist she became.
In her late 20s, she began work on her father's flea collection.
Over several decades, she co-authored a five-volume catalog.
Most would find this work drudgery, but for Rothschild, it was a labor of love.
I could sit at the microscope for hours and hours gazing down at these wonderful things
and the structures of these insects are so remarkable.
You know, the reproductive organs of the male flea are the most complicated in the world.
And it always fascinated me to look at all the different organs of these animals and
compare one with the other.
I found this riveting.
This drawing is typical of the illustrations in Rothschild's catalog.
Every joint and every bristle is faithfully rendered.
Of all the fleas in the collection, this is the most important.
It's the carrier of the bubonic plague.
Black Death, which killed off about a quarter of the inhabitants of Europe in the Middle Ages,
is really a disease of rats.
But when the rats die, the fleas that are on the rats move on to the nearest meal they
can get, which would probably be a man, and spread the disease.
They carry it on their mouthpots.
It was a tremendously difficult problem about 1900.
And my father was called on to illuminate this problem because he was a systematist.
He understood the difference between one flea and another because he was a student of the
group.
And this proved to be vitally important because the distribution of the plague in India, which
was then a very important part, depended a great deal on the species of flea.
And they're very difficult.
The ordinary person simply can't tell these fleas apart.
And so it's essential that you should have somebody who really understands the anatomy
of these insects and can tell one from the other.
Now this little microscope, very nice one, built about 1890, was the instrument on which
my father looked down this brass tube and could identify the fleas.
And this is a slide of one of the plague fleas that he discovered in Egypt in 1903 and decided
it was the chief vector of plague.
And of course, as he described it, bears his name tacked on the end.
It's called Xenopsila quiopis Rothschild, which I think is a great honor.
Thanks to the Rothschilds, we have come to know an insect that changed the course of
history.
Today Miriam Rothschild remains captivated by the mysteries of the small.
From collecting to cataloging, she and her family have left us with a priceless tradition.
Come on, dogs.
It's a tradition that's carried on today by scientists like Edward Wilson of Harvard University.
Wilson is the world's leading authority on ants.
Like the Rothschilds, he collects and describes new species.
He has about 100 to his name, and he's still counting.
A century after the age of the great collectors, insects are still being discovered.
I'm in the process of describing a new species of ant from Brazil.
I'm giving this one the species name Monstrosa because it has an abnormally large head and
because it has a peculiarly swollen shoulder region with extensions on the middle part
of the shoulder.
Its full name will be Phaidole Monstrosa.
Phaidole is the name of the group to which it belongs, the genus.
That's been known over 100 years, and Phaidole means the thrifty one.
I'm giving the new name Monstrosa to it, which means simply the monstrous thrifty one.
That should make it easy to remember.
You have to be able to tell species apart when you go into a rainforest or a prairie
or the deep sea or anywhere else before you can do any of the other biology, including
the most important parts of ecology.
And you have to know something about the relationships and evolution of these different species and
other entities.
The Chinese have a saying, the beginning of wisdom is getting things by their right name.
Describing a new insect is only the first step in biology.
The next is more challenging.
The creature's behavior must be understood.
Every morning, Wilson stops at a local florist to buy a bouquet.
Each stem is carefully selected.
But these flowers aren't the usual gift.
They're for his leaf cutter ants.
A leaf cutter colony is literally an ant farm.
They will harvest the flowers and use them to cultivate a fungus on which they feed.
This is agriculture on a grand scale.
Millions of ants work side by side, as if orchestrated by some invisible hand, each
attends to a specific task blind to its purpose, yet all for the common good.
Wilson pioneered the study of social insects.
Having a social group like an ant colony allows the sisterhood, that's what they are, sisters,
allows the sisterhood to blanket the surrounding environment all the time.
So they're monitoring it and controlling it all the time.
If you step back from an ant colony that's out foraging and let your eyes go slightly
out of focus, you see what appears to be something almost like a giant amoeba spreading out
from the nest with its pseudopodia reaching out and gathering in food.
And you can actually think of that unit, that aggregate, as an organism with the queen in
the middle as the reproductive organ and the workers like muscle and bone, the tissue that
extends out and gathers energy in to the central part of the body.
And the consequence of this is that by operating in such a well-unified, integrated manner,
a colony can present itself to the world as an organism and compete with other organisms
that are genuinely solitary and beat them out.
Leafcutter ants are the dominant herbivores of the New World tropics, that is, they consume
species for species more vegetation than any other kind of organisms, caterpillars, birds,
anything, and little wonder.
One leafcutter ant colony, full-blown with two to three million workers, consumes approximately
as much vegetation every day as a full-grown cow.
Insects devour more vegetation and pollinate more plants than any other living thing on
earth.
As a class, they have spectacular ecological clout.
If insects somehow vanished, most flowering plants would become extinct.
Insects are the original recyclers.
They are the primary scavengers of animals of all sizes.
They clear the forest of dead wood and leaves and turn far more soil than earthworms.
The first creatures to successfully colonize the land, insects, were able to diversify
unchallenged.
After 380 million years, they have a virtual stranglehold on the planet.
From rainforest to desert to urban jungle, insects are everywhere.
If insects are the ruling class, then the social insects, like leafcutter ants, are
the real aristocrats.
These groups, which actually date back about 100 million years, have come to dominate the
insect world and thereby a large part of the terrestrial environment.
Social life pays.
It's paid, for example, for human beings, almost sapiens as well.
We are the most social of all the vertebrates that ever evolved.
Together, we and the social insects run the terrestrial environment.
Most of us will never see a leafcutter.
But another social insect lives right in our own backyard.
It was the intricate organization of the hive that first attracted University of Illinois
entomologist Gene Robinson to honeybees.
I started working with bees in 1973.
At the time, I was a volunteer on a kibbutz in Israel, and I had been picking grapefruits
for many weeks and become bored stiff, and one day the work boss announced that there
was an opening for someone to work in the beekeeping operation, and I jumped at it.
From the first day working with bees, I was smitten.
What makes social insects successful is efficient division of labor.
Work is carried out by specialists.
In the hive, different bees do different jobs, and jobs change with age.
In effect, a worker follows a career path.
On a typical path, the entry-level position is housekeeping.
With her head buried in a cell, a worker spends her first days of life cleaning out the comb.
Next, a worker moves on to nursing.
Worm-like larval bees develop inside cells and depend on nurses to bring them food.
A nurse has a second duty.
She attends the queen of the colony, here marked with a white dot.
The queen, which can live for several years, is the mother of the tens of thousands of
workers in a typical hive.
The third week is spent at hard labor.
A worker clears debris, constructs the comb, and stores nectar and pollen in cells.
The final career move occurs at the beginning of the fourth week, when a worker becomes
a forager.
Only foragers leave the hive in search of food and water.
To study the hive's division of labor, Gene Robinson creates an unusual colony.
Out of the larval stage, every bee is one day old.
At this age, bees are easily handled.
They can't sting or fly.
Since bees of all ages are needed to conduct the business of a normal hive, how will these
youngsters cope without senior citizens?
Is the division of labor flexible?
Every day Robinson observes the entrance of his special hive.
It's now one week into the experiment.
Although workers normally don't forage until the fourth week, some of these bees have already
begun to leave the hive.
In Robinson's colony, career paths have been speeded up.
It's really quite an impressive acceleration.
What this means is that the colony must constantly be reallocating its labor in the face of changing
conditions.
To study the mechanism behind the hive's adaptability, Robinson collects a forager.
They're easy to spot.
The pollen baskets on their legs are filled to capacity.
From inside the hive, he also collects a nurse.
Robinson wonders if chemistry has something to do with speeding up a bee's career.
A blood test reveals that the level of a hormone is higher in a forager than in a nurse.
What does it actually cause a bee to switch to foraging?
To find out, Robinson treats a young bee with the hormone.
He marks it with a dab of paint to identify it later.
A dose of the hormone has put it on the fast track.
The bee forages a week ahead of schedule.
A hormone is involved in regulating the shift in behavior.
This is the first physiological mechanism that has been discovered.
It's involved in the regulation of division of labor, and it enables us to understand
how it is that intricate social organization is achieved.
Order beneath chaos.
Tens of thousands working together as one efficient self-regulating machine.
No wonder social insects have risen to the top of the ruling class.
One spring in Portal, Arizona, biologist Eric Green was conducting a study of birds.
While inspecting oak trees, he made a curious discovery.
I've been studying birds here for quite some time, and as part of this study, I've been
very interested in what the birds are eating.
So as a result, I spent a lot of time sampling insects in the trees simply to figure out
what's around for the birds to eat.
One day I was inspecting some catkins, oak flowers, and much to my astonishment, one
of the oak flowers started walking away from me, walked around the other side of the catkin
cluster.
I was shocked.
It turned out to be a catkin-mimicking caterpillar.
I collected the caterpillar and took it to one of the world's experts in this group to
try to put a name on it.
And he told me that it was impossible really to identify the species simply by the caterpillar.
It turns out that's not that unusual.
Many caterpillars have never been seen or identified.
In order to attach a name to this caterpillar, I had to bring it back into the lab, continue
feeding it catkins, let it pupate, and then hatch out into the adult form so we could
figure out what it was.
It hatched into a beautiful little emerald green moth, and it has the Latin name Pneumoria
arizanaria.
The moth was known, but Green was the first to identify its caterpillar stage.
That summer, after the catkins had fallen from the oak trees, Green discovered another
striking caterpillar.
It fed on leaves and was camouflaged like a twig as protection against birds.
Again I took it back to the lab, and it hatched out into an emerald green moth.
The amazing thing is that this moth was the same kind as the flower-eating form had turned
into earlier in the spring.
So the remarkable thing about this is that although the caterpillars look very different,
one like an oak flower, one like an oak twig, they are in fact the same animal.
To figure out what was behind the choice of disguises, Green would have to catch adults
in the wild.
If he can find a pregnant female, he'll be able to collect her eggs and raise caterpillars
in the laboratory.
Only a few nights in the year can the moths be caught.
If it's cold or windy, they will hide in the trees.
If the moon is bright, it will overwhelm the ultraviolet light.
And of course the emerald greens must be on the wing.
Tonight luck is with them.
At the Southwestern Research Station of the American Museum of Natural History, Green
runs an experiment.
He knows that the summer form of the caterpillar is different from the spring version, but
what factors drive the change in design.
Since spring is cooler than summer, Green raises caterpillars at different temperatures.
To see if they respond to the color of their environment, he also raises caterpillars under
different filters, yellow, the color of catkins, and green, the color of leaves.
Finally, diet is tested.
Green feeds some caterpillar's leaves and others catkins.
I found with my experiments that length of day, temperature, and color of the environment
had absolutely nothing to do with how these caterpillars turned out.
Apparently, the only thing that matters is the food of these young caterpillars.
So all caterpillars that eat catkins turn into the catkin form, and all caterpillars
that eat leaves turn into the twig form.
Now these two different diets have different chemical properties, and the species is able
to use this chemical information to have two generations a year, each with a very different
but effective disguise.
And in the evolutionary game of hide and seek, this species is remarkably fine-tuned to a
changing environment.
These caterpillars are living proof you are what you eat.
By masquerading as two different animals, each specially suited to its season, emerald
green moths double their chances for survival.
Over the course of their lives, most insects change shape.
It's been said that an insect larva is an enormous digestive tract hauled around on
caterpillar treads, a dedicated eating machine it cannot reproduce.
In comes metamorphosis.
Astonishing changes take place.
Old organs dissolve, new ones coalesce.
The nervous system is rewired.
Old senses wither, new ones bloom.
Where it emerges is a new animal, one fine-tuned for reproduction.
Metamorphosis is a great evolutionary achievement.
Flight is another.
Now insects could explore distant habitats.
No longer confined to the ground, they scattered and diversified.
Eventually, they would blanket the earth.
The first animals to fly, insects, had the skies to themselves for 120 million years.
The patterns in these fossil wings are tantalizing clues to a distant epoch.
At the University of Exeter in England, Robin Wooten examines this ancient record.
Trained as a paleontologist, Wooten became fascinated by prehistoric wings, but how they
worked was a mystery.
When I began work, nobody really knew very much about what their designs were about.
They just used to treat them as abstract patterns, which they would then classify.
It was clear to me that they were much more than this.
They were, in fact, elegant little pieces of microengineering, but I didn't understand
what they were about, and nor did anybody else.
After a while, I became frustrated by this, because it seemed that nobody was going to
be discovering what they were about.
And so I decided that I would have to start work on them myself.
To understand how insect wings are engineered, Wooten turns to the common housefly.
A special high-speed camera will capture them in midair.
Everyone who's tried to swat one of these realizes just how maneuverable and skillful
they are.
But when you see the things in slow motion, and can see the extraordinary aerobatics which
they perform, and the amazing things that they're doing with their wings in order to
do so, you realize just what fascinating insects they are.
Wooten found that the leading edge of the fly's wing, the part air passes over first,
can twist.
This model shows this.
It demonstrates a twisty leading edge spar, and off which come a series of parallel supporting
veins.
Here, when the wing is moving through the air, the aerodynamic force is applied in this
sort of region, and it twists the leading edge spar in this kind of way, so that each
of these supporting veins is raised to a greater extent as you go from the base to the tip.
There's an incidental and fascinating result of this.
If you look at the blue bands which move across, you can see that the very action of twisting
the leading edge actually imparts a curvature to the section of the wing.
The wing, in fact, becomes cambered from the leading edge to the trailing edge.
And this is a much more efficient aerodynamic structure than a flat plate would be.
An insect's wing uses tricks of design no human ever dreamed of.
An engineering masterpiece, it's an intricate, flexible mechanism that automatically adjusts
its shape to increase lift.
Perhaps elegance like this shouldn't be surprising.
Insects have been flying for millions of years, humans for less than a century.
While Robin Wooten studies the mechanics of wings, his colleague at the University of
Cambridge, Charles Ellington, is investigating the dynamics of insect flight.
The question is, should they be able to fly at all?
How insects like this hawk moth get off the ground has fueled decades of controversy.
The aerodynamics of airplanes was figured out by the 1920s.
Biologists were quick to apply the knowledge to insects.
By the 1970s, the conventional theory seemed to account for how they flew.
With improved slow motion and more exact computer analysis, Ellington took a new look at the
old theory.
The results were surprising.
When we applied the conventional analysis to the hovering flight of a dozen species
of insects, we found that for some of them, they simply should not have been able to fly.
The wings produce more lift than conventional airplanes should be able to.
And all of a sudden, we went from a situation where we thought we understood the flight
of almost everything to the situation where we understood the flight of almost nothing.
With the help of Robin Wooten, Ellington built a scale model of the hawk moth.
He calls it the flapper.
Actual moths manage a greater degree of supination on that leading edge.
That may be something which we have to worry about.
Concentrating the inner spindle entirely on this posterior part of the wing may possibly
have sacrificed some of the leading edge mobility.
If they can see how air passes over the wings, they may discover how lift is produced.
Still find this beautiful to watch.
The flapper may someday explain the hovering of a hawk moth or the flight of the bumblebee.
In the long run, it could point the way to new principles of flight, lessons from the
first creatures to conquer the skies.
Off the coast of Cape Cod, a team of researchers arrives at Pennekeys Island.
They are carrying one of only a dozen insects on the United States list of endangered species.
Insects may be the little things that run the world, but some of them are in trouble.
One university graduate student, Andrea Kozol, and Tom French, the Massachusetts official
in charge of endangered species, are trying to establish a new colony of American burying
beetles.
One year ago, they brought 20 pairs to Pennekeys Island.
Now they're back, setting traps to find out whether the beetles and their offspring made
it through the northeastern winter.
No one is sure why the American burying beetle has declined.
All that's certain is that they are far more rare than better known endangered species.
When the original endangered species list was put together, the species that first went
on, the great whales, the grizzly bear, the bald eagle, they were visible.
Everyone could see that they had declined.
The insects are not.
They're cryptic.
They hide.
And it took another 10 years of research to really know which ones were just very secretive
and good at it, and which ones really had disappeared.
Hundreds of private amateur collectors were collecting butterflies and, interestingly,
beetles.
There's such a variety of colors and sizes and forms of beetles that the amateurs had
collections that went back for over 100 years.
And that's where our information base now lies as far as the historic status of this
species.
If diversity is a measure of success, then beetles are overachievers.
Jacks of all trades in the insect world, they earn their livings in an astonishing number
of ways.
Unique among them are the many species of burying beetles.
They are the cemetery squad.
Within hours of its demise, a field mouse gradually disappears into a subterranean mortuary.
Here nature gives new meaning to the term recycling.
The beetles will work around the clock, grooming and embalming the carcass.
First they shave it, then to preserve it they cover it with secretions.
When they are done, the beetles will become caretakers of a combination crypt and nursery.
Up to 20 grubs are raised on the mouse.
Early in life they depend entirely on their parents.
The adults feed on the carcass, digest it, and regurgitate to nourish their young.
Child care is rare in insects, but in the burying beetles it pays off.
The grubs grow tenfold in weight per day.
They literally eat themselves out of house and home.
Most burying beetles are nocturnal, so taking a census on Pinakies Island requires some
work after hours.
Andrea Kozol and Tom French check the traps they dug that afternoon.
At the next trap is evidence they're on the right track.
Well, at least we have an orbiculus in here.
It's a burying beetle.
It's not the endangered one, but it's a burying beetle.
The traps are working anyway.
At least we got one of them.
Let's put him in here.
All right, good.
Why don't we check the ones at the bottom of the hill and see if there are any.
Yeah, let's see what we have in there.
Well, we've got one burying beetle in here.
Yeah, you're right.
There we go.
Which one is it?
I think it's one from...
Yes.
Yes, we have one.
With the discovery of an endangered beetle, Kozol and French know the program is working,
that transplanted beetles have survived.
So I guess that means they made it over the winter.
Last night we found nine adults of the American burying beetle here, and this is really excellent
news.
We won't know for several years to come whether this beetle can establish itself and maintain
itself on its own without all our assistance on Pinakies, but we do know that we can take
adults from a captive population, return them to the wild, and have them reproduce successfully.
Andrea Kozol continues to offer tender loving care.
The beetles that were trapped last night are given carcasses and set up in pairs.
She hopes the day will come when the beetles are strong enough in numbers to make it on
their own.
Does it really matter?
The American burying beetle is not the most charismatic of endangered species.
If it vanished, the environment would not collapse.
It's just a member of the cemetery squad, one of countless insects that seldom seen
quietly run the planet.
In Portal, Arizona, Tom Eisner stalks a darkling beetle on the desert floor.
Eisner is a civilized hunter.
His quarry today will serve in a study of insect defenses, a field he pioneered.
To protect themselves from predators, some insects armed themselves with chemicals.
Eisner, with the help of a colleague, was the first to identify the irritant produced
by this beetle.
Insect chemicals have been studied for the last 40 years, but only recently have scientists
begun to explore their potential as a source of drugs.
There's a group of water beetles, giant water beetles, that protect themselves against fish
by use of a secretion that they eject when attacked.
Well, one of these groups of beetle produces cortisone, the well-known medicinal drug.
If these beetles had been known to produce these compounds back in the 50s when cortisone
first came into medical use, one of these beetles would literally have been worth its
weight in gold.
Eisner has led a charmed life in science.
While most are lucky to chase down research projects, in Eisner's case, they chase him
down.
Two nights ago, I was lying in bed reading The New Yorker, and I know it sounds crazy,
but suddenly there was this shower of droplets from the ceiling.
Well, this was a very funny night because we hadn't closed the screen door very well
and a lot of moths had come in.
The next day, my wife opened the door and felt the same kind of fluid spray.
Then I felt it, and we suddenly started to suspect the moths.
Now, I'd never heard of a moth that sprays in response to being disturbed.
So I decided I'd play Predator.
I don't think I can reach it.
Oh, can't make it.
Damn.
I think I can get that one.
What about this one here?
Where?
That's the wrong moth.
Oh, sorry.
That's the wrong moth.
Can you watch the microscope?
Yeah.
I've got the vial.
Got it.
Okay.
And how?
Just take a look.
Terrific.
Oh, you can see the squirt.
Look at the water.
We haven't got the slightest idea what the fluid is.
I don't quite have the guts to taste it myself
because we found some neurotoxins and some secretions of millipedes,
and you don't know what this is all about.
But the very idea of a moth discharging a fluid in response to disturbance is a new event.
And given what we found in insect chemicals before,
it raises marvelous chemical questions.
Recently, chemicals have been found that help heal wounds,
act as sedatives, and prevent blood clots.
Eisner's motto might be,
so many insects, so little time.
To speed the search, he has enlisted an unlikely partner,
a wood thrush named Sybil.
How you doing?
It's a mealworm.
It's a goody for you.
She's an expert in insect chemistry.
She has to be.
Telling the poisonous from the tasty is a matter of survival.
Eisner offers Sybil an eclectic diet and records her reactions.
Today's appetizer is a grub.
Sybil gives it a three-star rating.
The entrée is the squirting moth from Arizona.
It's a good one.
Come on, you go get it.
Yes, you don't have to talk to me now.
If Sybil snubs the moth, that's evidence the spray is poisonous
and should be investigated for medicinal value.
If instead she eats it, that's evidence against a chemical defense.
It's nip and tuck.
Eisner must revise his theory.
Well, I wish there was something new about that squirting moth.
We've looked at it chemically and we didn't find
some mind-boggling unknown molecules to go after.
In fact, the fluid seems to be devoid of interesting organic molecules
and we're starting to think of that spray as being more
of a startling device than anything else.
Imagine the moth flying at night from the desert up the canyon
and being pursued by a bat.
When that bat is at close range, ejecting just a jet of fluid
that hits the face of that bat may be enough to throw that bat off
ever so slightly, giving the moth an edge.
That's our current thinking.
The final course on today's menu is a firefly.
Try a firefly.
It's been a long time since you've seen anything like that, huh?
Sybil turns up her beak at the offering.
Either through experience in the wild or innate wisdom,
she avoids the firefly.
For Eisner, this proves to be an important clue.
Of the hundred or so species of insects that we fed to the bird,
five were the ones that the bird hated the most,
and each one of these five turned out to have interesting new chemicals,
including chemicals of potential medicinal value.
In the fireflies in particular, there were compounds of interest.
There were a new group of steroids.
These are the kinds of compounds that one can expect to have
heart-stimulating activity, but most interesting,
compounds that have recently been shown to be antiviral.
I've spent most of my life looking for chemicals in insects,
but I've only had a chance to look at a few dozen species.
Imagine what might be in store.
One should screen them systematically for chemicals.
One should mount a program, call it chemical prospecting.
I'm willing to bet that some of these miracle drugs
that have so far been found in plants and microorganisms
might have great unknown counterparts in the world of insects.
A million variations on one fundamental body plan,
a million hiding places for new medicines.
The quest will continue and may well depend on the next generation.
Take a look.
Go ahead. You can put it on your finger, but don't put it close to your face.
So why do you suppose it's so peaceful and not running all over the place?
It must have some sort of defense to surprise enemies.
And it's got a real defense.
I'm going to catch it as if I was an enemy trying to grab it and eat it, okay?
Mm-hmm.
The female, male and the female, they have a chemical defense.
Don't inhale too deeply.
Feel it? Okay, that's the defense.
You can even see my fingers wetted from this stuff.
It stinks.
It stinks, and it's a very powerful spray.
When we first encounter them, insects are a source of curiosity and delight.
Those who remain captivated know we share the planet
with a remarkable class of animals.