The real dragons of today’s world stomp around like dinosaurs in the remote equatorial hills of their namesake island in Indonesia, Komodo. While these giant lizards may not fly, or breathe fire (although their bacteria-laden saliva is deadly), they are capable of a feat equally miraculous: virgin births.

In 2006, Flora and Sungai, two female Komodo dragons housed at the Chester and London Zoos, respectively, were the first discovered cases of virgin birth in the world’s largest lizard. They are examples of a process called parthenogenesis, the scientific term for single-parent reproduction. This process is almost never seen in animals as complex as the Komodo, and has only been documented in 0.1 percent of vertebrates, according to a report in the December 2006 issue of the journal Nature.

After the discovery, Richard Gibson, a curator of herpetology at the London Zoo, said in a National Geographic article that virgin birth is “considered a very rare phenomenon, but the fact that we’ve got these two lizards suggests it’s not as rare as we thought. We recorded it in two unrelated females within the space of a year in two different collections.”

Virgin births, by the process of parthenogenesis, happen when an unfertilized egg develops into an embryo using its two sets of maternal chromosomes. Scientists are more familiar with parthenogenesis in smaller invertebrates, such as aphids and zooplankton. In evolutionary terms, single-parent reproduction is not the best way to make babies. The gene pool of an isolated population dependent upon parthenogenesis becomes smaller, making it more vulnerable to disease and less adaptable to altered climate conditions or new predators.

There is, however, a unique advantage to the female Komodo’s self-sufficiency. As a denizen of a chain of desert islands in Indonesia, a female dragon might very easily be swept away from her island to another island where no other dragons live. Yet she still can reproduce parthenogenetically and keep the species going. Gibson explained that because of the genetics involved in lizard self-fertilization, the offspring are always male. As soon as those baby boy lizards grow up, they can then reproduce with their mother. Eventually, a male dragon from another island might wash up on shore and diversify the gene pool.

That’s not all that makes the Komodo remarkable. It also shares a mythical dragon’s predatory prowess. A member of the goanna family, with ancestors that date back more than 100 million years, the Komodo shares the feeding and dental characteristics of extinct dinosaurs, sharks, and sabre-toothed cats, according to a study released in the April 2008 issue of the Journal of Anatomy.

Given their ability to attack and butcher very large animal prey, one might assume the Komodo dragon would possess a steely, snapping jaw like an alligator’s and a dense, sturdy skull. The opposite is true. The Komodo’s physiology is distinguished by what scientists call a “space-frame” skull, made of a light, rigid structure with interlocking struts that can handle big loads. What’s key is the shape of the bones and the way bones of different strengths are arranged. Instead of clamping down like an alligator, the dragon rapidly yanks off chunks of meat, and its powerful neck muscles and space-frame skull support the forces involved. Sixty razor-sharp, serrated teeth help, too.

According to one of the scientists behind the report, Stephen Wroe of the University of New South Wales, the Komodo could do serious damage to even buffalo-sized prey. Quoted in an article in ScienceDaily, Wroe said, “The Komodo displays a unique hold and pull-feeding technique. Its delicate skull differs greatly from most living terrestrial large prey specialists, but it’s a precision instrument, beautifully optimized to make the most of its natural cranial and dental properties.”

The Komodo was discovered by Western scientists in 1910, and its total population in the wild is estimated at 4,000 to 5,000 individuals. It can grow up to 10 feet long (3 meters) and weigh more than 300 pounds (136 kilograms). Its tremendous size is a result of island gigantism, as Komodos are the apex predators, dominating the ecosystems in which they live.

Photo © WNET.ORG/Icon Films

They fly, float, hitchhike — and even explode. But the many clever ways seeds get around make sense: after all, a plant’s life depends on finding fertile ground in which to grow. The quest for survival has even led plants to develop delightful and devious ways of fooling us into working for them as they send their seeds out to conquer new lands.

But the plants’ master plan for world conquest is no longer a secret. NATURE’s The Seedy Side of Plants rips the husk off the many remarkable ways plants make sure their offspring are spread far and wide. Apples make themselves as red and tempting as possible to encourage us to pluck them and take a bite so the seeds inside can escape to new ground. An African melon has a mouth-watering method of convincing aardvarks to go to the trouble of tunneling deep into the earth to liberate a few tough pits.

There is no doubt that plants are one of the world’s most successful life forms. Indeed, Earth is a planet of plants, with millions of kinds growing in virtually every environment imaginable, from the driest deserts to the wettest jungles. Even paved parking lots often display a few tufts of tough grass poking up through the cracks. But it didn’t take a gardener’s green thumb to design this global garden. Plants did it themselves, millions of years before humans ever appeared, by evolving countless methods of producing and spreading seeds. These tiny packages of genetic material have proven an almost unstoppable means of ensuring a species’ survival.

At first glance, some seeds’ designs make plants seem downright intelligent. Take apples, for instance. As The Seedy Side of Plants shows, these sweet fruits have evolved to be bright and shiny for good reason: they attract people and other animals. Drawn in by their effective advertising, we do the work of carrying apple seeds to new territory where the species can gain a toehold and expand. Indeed, we like apples so much that we’ve planted orchards especially for our favorite fruit. The practice has prompted some biologists to ask who really is the boss in this relationship: do the apple trees work for us — or do we work for them?

Similar examples can be found throughout nature, from fig-eating bats that become unwitting cargo planes for fig seeds, to squirrels and woodpeckers that unknowingly help oak trees spread their acorns. The Seedy Side of Plants even includes the remarkable tale of an African melon that grows a gourd-shaped bladder of water deep underground. In the dry season, aardvarks sniff out the watery melons, digging deep to quench their thirst. In the process, however, the thirsty aardvarks also sip up a few pit-like seeds, which they later deposit inside fertilizing manure. It’s hard to say who gets the better end of the deal: the melon or the mammal.

Both plant and animal, of course, get something out of these mutually beneficial relationships. Apple trees, for instance, didn’t set out to fool people into picking their fruit. But somewhere along the line, certain apple trees ended up with a combination of genes that made their fruit a bit brighter or sweeter than all the other apples. Since we liked these apples so much, we began selectively planting the trees, and learned how to breed even sweeter varieties. In exchange for the tender, nutritious fruit, the trees get steady care and even protection from potential enemies, such as insects and browsing deer.

Evolutionary accidents may explain how other types of seeds developed, too. On the island of Mauritius, for instance, there once were trees that dropped their tasty fruits full of seeds to the ground. Then, a new bird arrived on the island. It loved the fruits, but the tree’s seeds couldn’t survive the trip through the bird’s stomach. As a result, the tree was in trouble, since fewer of its seeds were surviving. Then, perhaps through a random genetic mutation, one tree, the calvaria, produced fruit with tougher seeds that could survive being eaten by the birds. Given this significant advantage, the tougher calvaria soon began to thrive. Eventually, they crowded out their ancestors completely.

As The Seedy Side of Plants shows, however, evolution can sometimes produce a plant that is too reliant on a particular animal for survival. That’s exactly what happened on Mauritius. There, some biologists believe that lonely 300-year-old calvaria trees await a bird that will never return: the dodo. In 1598, Dutch explorers established a colony on Mauritius. In the search for food to eat and sell, the settlers plundered the island’s natural resources, killing giant turtles, lizards, and the huge, flightless dodo birds with abandon. When the settlers did in the dodo, however, they may have also put the death of the calvaria in motion. Some biologists believe the dodos ate the tree’s fruit, and that the trip through the bird’s stomach helped prepare the seeds for germination. But now that their partner in life is gone, only a few calvaria survive. They are silent reminders of a lost past, with their seed-bearing fruit littering the ground and inviting a feast that will never come.

Plants have spent millions of years learning how to produce seeds that can ensure the birth of a new generation of plants. And people have spent thousands of years struggling to control that powerful force, breeding plants that produce more and better seeds than ever before. Indeed, modern agriculture depends in large part on our ability to control seed production: not only are seeds, from rice to wheat, a major source of our food, but we also depend on being able to store and plant them for the next year’s crop.

Now, however, scientists armed with the tools of modern genetic engineering are engaged in a controversial attempt to turn back the evolutionary clock by creating plants whose seeds do not work. Why would researchers want to prevent a plant from reproducing?

The answer lies in the economics of modern farming, where farmers in industrialized nations are willing to pay a fortune for seeds that can guarantee a bountiful harvest. But such revolutionary seeds are also expensive to develop, and seed companies are spending billions to engineer new varieties of many modern crops — from corn to cotton — that grow or taste better. In the past, a farmer may have been able to buy these relatively expensive seeds, harvest a crop, and then, by saving some of the seeds produced by the superplants, plant a new crop the next year without having to buy a new batch of seeds. Understandably, some companies were unhappy about spending so much to develop seeds that could be so easily “stolen.”

So now, these companies have figured out a way to turn off a plant’s ability to produce viable seed. By inserting a certain gene into the plant, the seed-growing process is short-circuited. While the plants produce lots of seeds, the packets are all sterile.

This “terminator technology,” as it is popularly called, isn’t yet out on the market. It is still being fine-tuned in the laboratory and in test plots. But it has already prompted protests around the world, particularly from poor farmers who depend on saved seeds for the next year’s crop. And some biologists worry the trait could somehow spread to related wild plants, endangering their ability to reproduce. The companies say such fears are unfounded and promise they won’t release the seeds until they’ve been shown to be safe.

The debate is unlikely to be settled soon, but it shows that even seeds no bigger than a speck of dust can spark huge debates.

In their quest to spread their seeds, plants have proved endlessly adaptable. Some, such as dandelions, produce spores that can fly miles on a puff of wind. Others, like coconuts, have engineered seeds that can survive thousand-mile voyages at sea. Some of the most remarkable seeds, however, are those adapted to survive fires so intense they kill virtually everything else in their path.

Many of the world’s pine forests, for instance, grow in arid climates, where a single flash of lightning can spark an inferno. Trees that couldn’t take the heat died out long ago. Those that remain generate seeds that are fire-hardened better than any high-security safe, able to protect their precious genetic cargo from the heat.

Some seeds, however, recall the mythical Phoenix, a bird that would rise from a fire’s ashes to begin life anew. To thrive, these seeds actually need to get burned: intense heat is required to explode their seed cones or crack their hard kernels, so that water can leak in and begin the growth process. Such “fire-germinated” species are common everywhere forest fires occur on a regular basis. In an ironic turn of events, the recent campaign to stamp out forest fires has put some of these species in jeopardy. Indeed, in some parks, rangers now intentionally set forest fires just to make sure certain plants grow.

Many prairie species, for instance, only sprout after fires clear the way. That has made the spring “prairie burn” an annual ritual throughout much of the Midwest, with teams of fire-wielding plant-lovers tromping into the fields in a quest to imitate the grass fires that once swept across the plains. In Michigan, biologists have also become fervent arsonists in an effort to make sure there are enough young jack pines, a kind of tree essential to the survival of an endangered songbird called the Kirtland’s warbler. For some reason, the bird will nest only in the young pines — and the trees will grow only in recently burned forests. That’s because fire is needed to get the pines’ tough cones to crack open and release their cargo of seeds.

Recently, however, biologists have learned that flames aren’t enough to unlock some fire-resistant seeds — they need the smoke as well. In the 1970s, researchers discovered that some seeds germinate when exposed to the merest whiff of wood smoke, even if the seed is buried in the soil. The response makes sense: the seeds can wait years underground until smoke reveals that a fire has taken place overhead, filling the soil with fertilizing ash and clearing away plants that might block the seedling’s light. Having gotten its smoke signal, the young plant can take advantage of the disaster.

But smoke is made of literally thousands of chemicals, and researchers have long puzzled over which ones might be triggering the seeds. Then, in 1997, researchers Jon Keeley and C. J. Fothereringham of Occidental College in California were able to pin down one of the responsible agents: a gas called nitrogen dioxide. They discovered that the seeds of a common wildflower called yellow whispering bells germinated when exposed to even tiny amounts of the gas. The discovery, however, had a troubling side. Nitrogen dioxide is produced by natural fires — but it is also one of the most common pollutants produced by cars and power plants. Tons of the compound fall to Earth every day, carried by rain and dust particles. Some botanists fear the pollution could be tricking sleeping whispering bells seeds into thinking a fire has occurred — causing them to sprout beneath the deadly shade of another plant. That would mean fewer seeds would be around when a fire really occurs.

Like other plants, however, even whispering bells show creative variation in getting their seeds to sprout. While those that live in fire-prone areas need smoke to germinate, whispering bells living in deserts, where fires are scarce, don’t respond to smoke at all. Instead, they have evolved a clever response to the desert’s scouring winds. For these seeds to germinate, they must be blown across rough sand, which scratches the seed’s outer coat. Moisture then leaks in through the scratches, signaling the seed that it is time to grow.

Such strategies don’t surprise botanists. Says one: “If you can think of a way to get a seed to sprout, you can be sure some plant is already doing it.”

They’re cunning and manipulative, and will do anything to get what they want. No, it’s not the cast of your favorite daytime soap. We’re speaking of the ubiquitous plant life that covers our planet, relentlessly evolving elaborate schemes to disperse its seeds and ensure the continuation of its almost limitless species.

How does such a seemingly passive life form accomplish the complex task of reproduction? Many plants take advantage of the primeval forces of Mother Nature herself to help their seeds germinate, sending them far and wide by means of wind, rain, and tides. Others have found ways to hitch rides for their seeds aboard other living things. For example, the burdock plant, which inspired inventor George de Mestral to create Velcro, has pesky burrs that sticks stubbornly to hair and fur.

Fruit, however, is perhaps the most commonly employed medium of seed mobility. Fruit-producing plants rely on the appeal of their fruits for dispersal of the seeds, and have evolved their own unique “marketing strategies” and their own select clientele — animals as well as humans — to help the process along. Even as scientists develop methods to control plant reproduction, each time we yield to the temptation to pluck a ripe juicy apple from its branch, we too become pawns in one of nature’s carefully devised game plans.

Online ontent for The Seedy Side of Plants was originally posted May 1999.

Producer: Ronnie Godeanu

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Designer: Lenny Drozner

Writer: David Malakoff

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About the Writer

David Malakoff is a journalist covering research discoveries and the politics of science for SCIENCE MAGAZINE in Washington, D.C. His writing has appeared in a wide range of venues, including THE ECONOMIST, THE WASHINGTON POST, and ABCNews.com. He lives with his wife and three children — NATURE lovers all — in Alexandria, Virginia.

Television Credits:

A co-production of Green Umbrella Ltd., Thirteen/WNET New York, Trebitsch Produktion International GmbH, and Devillier Donegan Enterprises

Funder Credits

Funding for the TV series NATURE is made possible in part by Park Foundation. Major corporate support is provided by Canon U.S.A., Inc., Ford Motor Company, and TIAA-CREF. Additional support is provided by the nation’s public television stations.

In a mountain rainforest on the island of Trinidad, at the narrow entrance to a deep and noxious cave, TRIUMPH OF LIFE series producer Nick Upton and cameraman Jim ClarBatse prepare for an unusual challenge. Several hundred thousand bats, including vampire bats, live in the cave, along with millions of other creatures. When darkness comes, the bats will rush to fill the night sky. Upton’s goal is to film this fantastic exodus from inside the cave. The results are on view in the six-part NATURE series TRIUMPH OF LIFE.

From Nick Upton’s Diary:

“This is our sixth day at the cave. With luck, it will be our last and we can move on. I won’t miss lugging the equipment up that mountain terrain, and then lowering it piece by piece on a rope down a 30-foot shaft into the caveBats. But that isn’t the worst of it. When Jim and I need to clear our access ladder for a scene, we’ve had to enter the cave through the squeeze hole — an incredibly narrow passage that you have to wriggle through feet first. It bends in the middle and ends in a four-foot drop into piles of bat guano. It’s no joke, especially for a six-foot-three, 210-pounder like me. I’ve come close to getting stuck more than once. And all the while you’re maneuvering, bats are fluttering near your face and the cockroaches are skittering along the walls. We did this as many as six times some nights. Once, when I was about halfway through the squeeze-hole by myself, I knocked out the battery of my head-lamp and was stranded in total darkness. It took several jittery minutes to reinsert the battery and reconnect its wires by touch. Of course, I knew Jim would look for me eventually, but being wedged in solid rock with all that life teeming around me in the darkness made those minutes feel like hours.”

Night of the Guano

“The darkness, however, is by no means the only threatening aspect of this environment. The extreme heat and humidity are stifling, and the air is acrid with gases rising off the huge heaps of guano. Inhaling fungal spores in the air can cause a serious disease called histoplasmosis, so we wore face masks all the time. As for the creatures that share the cave with the bats, most are harmless, even the creepy-looking whip scorpions. But it’s essential to watch out for the poisonous snakes. The intense heat means that protective clothing is out, and one night I was bitten by a blood-sucking bug that sometimes carries a debilitating disease. But I managed to dislodge it before it could really go to work.

“Despite all the creatures in the cave and the dangers of navigating it, one thing above all else stands out as the most objectionable aspect of this underground environment — it seethes with millions of four-inch cockroaches. They live on the bat droppings and sometimes the ground actually seems to pulsate with them. In truth, the roaches aren’t really a physical danger, but they can be a bit disconcerting when they fly into you in the dark or crawl under your shirt.”

Rescuing the Pups

“Perhaps this will surprise some viewers, but the bats pose no danger either. BatsAnd that’s just as well, because in a few moments, Jim and I and a camera will be positioned between the cave’s exit and the third of a million bats that will fly past us at full speed. This should allow us to capture an amazing spectacle. So far, we’ve recorded some truly intimate aspects of bat behavior, such as feeding, breeding, and the dramatic rescuing of bat pups that fall from the roof of the cave by ‘baby-sitter’ bats. Until now, this fascinating behavior had been witnessed only by a handful of researchers. Capturing these scenes required a subtle touch. We used an infrared filming system to avoid disturbing the bats, and spent five long days in the cave, working in total darkness most of the time.

caption goes here

“However, the bats aren’t nearly so sensitive leaving the cave, and so for this scene we’ll use normal filming lights, powered by a large generator, which, by the way, we and our guide had to drag up the mountain, nearly killing ourselves.”

Exodus

“The sun has gone down, and already we can hear thousands of bats flitting around in a deeper portion of the cave, calling loudly. The charge is about to begin, and Jim and I have done all we can to prepare ourselves. And here they come, directly towards us, whizzing by our faces by the hundreds at first, then quickly by the thousands, the tens of thousands, the hundreds of thousands — pouring out into the night through the narrow exit. On and on it goes, for 40 heart-stopping minutes. But it seems like only five minutes to us, as we frantically switch lenses, change camera positions, adjust the lights, and record the eerie sounds.

“This is our chance to record this moment forever. It has been one of the most amazing experiences of my life — an entire civilization of bats swooping past us just inches away. And what an unforgettable demonstration of the astounding accuracy of their sonar abilities, for not one bat ever struck us! For the unique achievement inside that cave, I have the greatest admiration for my long-suffering cameraman. Jim seemed totally unfazed by the conditions; but then, he’s one of the real ‘hard men’ of wildlife filmmaking. As for me, despite all the hard work and discomfort, I find myself lookingBat forward to returning here some day. There is much more to film and to learn. Bats are remarkable animals, far more intelligent and sociable than people realize. I feel privileged to be in their strange, underground world and to have the opportunity to share the experience with the viewers of NATURE.”

A Powerful Organ Hearts, eyes, flippers and wings — evolution has forged many remarkable body structures. But none is more amazing than the brain, that bundle of nerve cells that allows us to sense our surroundings, sort out information, and make decisions. Indeed, the great importance of BRAIN POWER to evolution is the subject of this week’s installment of NATURE’s TRIUMPH OF LIFE series.

Brains are not essential to life. Many organisms, from algae to jellyfish, get along just fine without a central information-processing center. But there is no question that a brain gives many animals an edge. For in the struggle for survival, brawn often gives way to a brain that can outthink a competitor.

Not all brains are equal, however. Some brains consist of just a few hundred or few thousand cells, just enough to sense changes in light or temperature, or to sniff out important smells. Others, like ours, contain billions of cells, enabling everything from language to tool-making.

But simple is often more than enough to assure an animal’s survival. A flatworm’s basic brain, for instance, helps it sniff out earthworms, making the worm a lethal hunter. And while a honeybee’s brain is bigger than a flatworm’s, it is still not all that complex. Nonetheless, the bee is capable of amazing feats of memory, as BRAIN POWER shows.

In their short two-month lives, worker bees must learn to remember where nectar-producing flowers are located in relation to the hive, and exactly what time of day they produce the sweet liquid. The life-or-death memorization is aided by an amazing change in the bee’s brain: as it needs to retain more information, the brain grows, adding tens of thousands of cells on an as-needed basis! Once, scientists believed that such brain-changing abilities were limited to just a few animals. In recent years, however, evidence has shown that many animals’ brains are more flexible than once thought possible. Some birds, for instance, grow new brain tissue during the breeding season — perhaps to sing more complex songs — then lose the cells once mating is over. Other bird brains grow or shrink for migration.

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Watch this clip to find out how a bee’s brain can sense changes in time.

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Researchers have even had to rethink their views of the human brain. Once, they believed that our brains grew only during childhood. It was believed that once we reached adulthood, we only lost — and never gained — brain cells. But surprising new studies show that we continue to add some kinds of brain cells throughout life. And other research shows that although our brains are usually very specialized, with particular parts responsible for certain activities, the human brain can sometimes reorganize itself. People who have lost speech or coordination due to stroke or brain injuries, for instance, can sometimes regain those abilities by “training” a new part of the brain to take over. Such findings have raised new hopes for treating serious brain injuries and birth defects.

Scientists, however, are still puzzling over the question of why we evolved such big, complex brains. Clearly, they are a big help in outsmarting predators and finding food. But our brains may also be a product of social pressures. We expend enormous energy in forging complex social relationships and alliances, whether within a family, among neighbors, or among nations. Making these relationships work requires creative thinking, constant problem-solving, and the ability to understand how another person is thinking — all tasks that call for some serious brain power. Over time, evolution favored those individuals with the best social and survival skills.

For the moment, our brains have made us the most influential species on earth. Our tool-making skills have allowed us to reconstruct the landscape, building cities and plowing fields where forests and grasslands once reigned. We’ve figured out how to make the desert bloom, pumping water from far below the earth to quench our thirsts. And, unintentionally, we may even be altering the planet’s climate by burning massive quantities of coal, oil, and wood that produce carbon dioxide and other global warming gases.

It remains to be seen, however, whether even our brainpower will help us avoid the fate of so many other species in Earth’s history: extinction.

Gene Swapping Variety is indeed the spice of life. That is the message of THE MATING GAME, Part 2 of NATURE’s six-part TRIUMPH OF LIFE series. It takes a passionate look at the evolution of sex, which allows a species to pass its genes along from generation to generation.

Sex is everywhere. Bees do it and birds do it — and so do lizards and bacteria. In its simplest form, sex is the process of mixing genes from two parents into a new offspring. This gene swapping ensures that each generation is just a bit different from the one that came before, and that each individual is a bit different from others.

This variation gives the species a better chance of surviving changing conditions. A few individuals, for instance, might be able to survive a deadly new virus and carry on the species, while the rest die. Eventually, the virus-resistant newcomers might even evolve into a new species.

Just because sex is everywhere, however, doesn’t mean that all organisms do it the same way. Evolution has produced virtually every conceivable combination of mating behaviors, as THE MATING GAME shows.

A male’s bird’s bright plumage is more than just eye-catching. Colors can also tell a potential mate about the man’s health a vigor.

In some species, for instance, the males compete with each other for the chance to mate with females. But in others, it is the females who vie to be the more attractive mate. Sometimes, the female is bigger, in order to hold more eggs. But in others, such as humans, the male is typically a bit larger. In some species, the females do most of the hard labor of child rearing; in others, it is the male that does all the work. And in some species, such as many marine fish, the kids are left to fend for themselves.

Other animals have evolved especially creative approaches to sex. Some female lizards, for instance, don’t need males to reproduce. Each female can lay eggs that produce “clones,” or genetically identical baby lizards. While cloning allows the species to reproduce under very harsh environmental conditions, it also leaves the identical offspring much more vulnerable to disease or environmental changes.

Some marine worms have taken another approach — each individual is both male and female. These “hermaphrodites” have the option of being mother or father. And a few fish take the idea in another direction. They can change sexes depending on circumstances, spending part of their lives as males and part as females.

It all goes to show that sex is never simple. But it has proven an essential engine for the evolution of life on Earth.

Choreographed Cooperation Life may be a contest in which only the fittest individuals survive, but cooperation has also played a key role in evolution. WINNING TEAMS takes a close look at the alliances that animals have forged — with others of their own kind and very different organisms — in a bid to stay alive. In fact, teamwork occurs everywhere, from flocks of birds and herds of wildebeest to colonies of ants and termites.

For some animals, the motivation for joining together is defense. A flapping, pirouetting flock of birds, for instance, can make it harder for a hungry falcon to home in on a single victim. Similarly, a thundering, shifting herd of wildebeest can be an intimidating — and confusing — sight to a hungry lion. And in both cases, there are more eyes to keep on the lookout for attackers. There is, indeed, safety in numbers.

Not surprisingly, some predators have responded to herding defenses with teamwork of their own. Feeding dolphins, for instance, have been known to work together to herd schools of fish toward the surface, where the seafood meal finds it harder to hide. Lions also team up to spring the trap on wildebeest, with several lionesses needed to topple one of the big beasts. And early human hunters, of course, learned to work together to hunt creatures, such as woolly mammoths, that were many times their size.

In many insect societies, every individual in a hive or colony can be the offspring of a single queen, making them all siblings that share genes.

Other times, however, the benefits of teamwork are less obvious. Animals that feed together, for instance, can spread out and cover more territory, making it more likely that one will hit a mother lode of food. The strange Damaraland mole rats featured on WINNING TEAMS, for example, drill through the soil as a team of up to 40 family members, looking for the roots and tubers that fill their empty stomachs. For years, researchers were unaware of this choreographed cooperation, since the underground-living rats are quite secretive.

Similarly, the link between some plants and the birds that eat their seeds took years for researchers to recognize. These plants, which include some wild rose bushes, produce tough berries that, if dropped on the ground, won’t sprout. But if the same seed is eaten by a bird, and is then etched and cleaned by the bird’s stomach acids and excreted onto the ground, it is ready to germinate. Similarly, some flowers can be pollinated only by a particular insect. The arrangements have led some scientists to ponder who is getting the better deal: Are the birds and insects slaves to the plant, or is it the other way around? The answer lies in their “symbiotic” relationship — meaning both organisms benefit mutually from the other.

Often overlooked is the important role that microscopic organisms play in the lives of many plants and animals. Some of these “symbiotic” bacteria live on the roots of plants, helping them draw nutrients from the soil. Others reside in the stomachs and intestines of everything from termites to humans, helping to digest food and remove toxins.

Without us, our stomach bacteria would die. But without the bacteria, we might fall prey to illness. It’s a classic case of the evolutionary ties that bind all life together in the drive to build highly competitive — and ultimately winning — teams.