The Human Age: The World Shaped by Us

Is Nature “Natural” Anymore?

I am writing this in a bay window that floats halfway up an opulent old magnolia tree, which unfolds waxy pink brandy-snifter flowers in the spring, and offers lofts to wrens and chickadees, perches for owls and wing-weary hummingbirds, syrup for yellow-bellied sapsuckers, leafy pounce-ways for squirrels. Its neighbor, a colossal sycamore, hunches dozens of crooked branches to the sky, and catches sunlight in fuzzy leaves the size of bear paws. The deer turn to it for shade, the brown bats for shelter, the goldfinches for edible ornaments. Both trees fork and flow like river systems of sap with many tributaries. They bargain with insects and animals, keep their own time, and possess impulses and know-how I barely understand. Brainless the trees may be, but they have tiers of memory, powerful urges, skills, and faculties. We’re all offspring of one crusty planet, but we’re so different that we sometimes seem to inhabit alien universes. Even the criminal mind is more explicable than a tree—a quiddity we cannot enter, an essence that does not include us.

Like most other people, I find the magnolia, the sycamore, and the animals part of a wild green spontaneous expanse, where other creatures with other pedigrees are busy pursuing their own cycles and mysterious purposes. In a human-centered world, the otherness of nature is part of its great comfort and allure. For Bill McKibben, “nature’s independence is its meaning; without it there is nothing but us.”[9] Ancient beyond our imaginings, nature offers us a refuge from human affairs, a world free from social labyrinths, romantic tangles, hopes and hurdles. Or so it seems. But is this really true?

My magnolia belongs to a genus more ancient even than bees (beetles pollinated its ancestors), and certainly older than humankind. The story fossils tell is that a magnolia can trace its roots back a hundred million years. Its family has survived ice ages, the uprising of mountains, and continental drift. Its lineage may be older than the Finger Lakes hills. Yet it didn’t begin its life in my chilly yard. Aztec admirers named it Eloxochitl, the tree with green-husked flowers. Spanish explorers in the New World, enchanted by the large waxy petals that blushed like a maiden’s cheeks, ferried magnolia roots home along with the new luxuries of chocolate, vanilla, and brilliant cochineal-red dye. By the 1730s magnolias adorned many European gardens and were hybridized with other species, evolving into the robust ornamental magnolias that ultimately voyaged back across the Atlantic to grace southern homesteads, where they were usually planted in the front yard. In time horticulturalists sold their novelty to northern nurserymen, one of whom sold it to the original owner of my property, an entomologist, who no doubt watered, fed, and tended it lovingly.

This stately old magnolia is so bound up with human schemes and follies that it’s not exactly “wild” but rather part of our man-made world. It’s more akin to a domestic animal that lives in partnership with humans, providing beauty and a remembrance of the wilderness. The same is true of the sycamore. Although I live atop a hill, sycamores usually grow on the margins of rivers, or in wetlands, thriving on green banks between a field and a stream. Opossums, wood ducks, herons, and raccoons nest in a sycamore’s many cavities and branches. Native Americans sometimes used the entire trunk of one tree to carve a dugout canoe. It’s covered in apple-shaped fruits, each one a tiny Sputnik tufted with brown hairs and full of seeds. But my sycamore is really a disease-resistant hybrid of an American and an Oriental sycamore. So it, too, is a traveler, or at least its genes are.

As for the wild birds, I feed hummingbirds sugar water and put out seed for the dark-eyed juncos, nuthatches, and finches. Many of the crows wear armbands, as if in perpetual protest. They’re being studied by local ornithologists, and each band bears numbers, a favorite human logo. The tags are applied with care, and I don’t think they hamper the birds. I sometimes see a crow preening its tag into place as if it were another feather. But, like the trees, the birds don’t live detached, independent lives. Humans have meddled with their whereabouts, numbers, health, and gene pool.

In contrast to life indoors, I regard this landscape full of birds, trees, and animals as “nature.” From that perspective, the telephone poles and fence on the property line, the TV cable and metal mailboxes, the asphalt street and grumbling cars and distant arpeggios of downshifting trucks, all belong to the crafted world of humans, an artificial paradise filled with ceaseless blessings and hardships.

The myth of our sprawly, paved-over cities and towns is that we’ve driven native animals out and stolen their habitat. Not entirely true. We may drain the marshes, level forests, and replace meadows with malls, exiling some animals. But, because we also need nature, we create a new ecology that happens to be very hospitable to wild animals. For a few species, it’s more inviting than wilderness. Our buildings offer cubbyholes and crevices for animals to nest in. We install ponds, lawns, groves of edible trees. We leave garbage on the curb and design flower beds that are well watered and well fed, serving a smorgasbord of delicacies easily within a deer’s reach. In the process we keep fashioning new niches, most often without meaning to.

Anthropocene cities have created pools of a limited number of species, the ones that coexist well with humans—mainly deer, rats, cats, birds, foxes, skunks, raccoons, houseflies, sparrows, mice, and monkeys. One finds such city species wherever animals are forced to live in our shadow, feeding on our leavings, and joining the fossil record beside our steel and plastic. But we’re restyling their evolution, because urban animals (including humans) vary their habits and psychology to adjust to city life. Animals living in parks and zoos also adapt to our natural biorhythms and landscapes.

As more birds harbor in the cities, they find plenty to eat, but their biological clocks skip ahead. When Barbara Helm, a University of Glasgow ornithologist, compared blackbirds in Munich with their country cousins, she found that city birds start their workdays earlier and their biological clocks tick faster. Just like their human counterparts, they adopt a faster pace, work longer hours, and rest and sleep less in cities where upward-showering light washes out the stars and our handmade constellations cluster near the ground. Urban males also molt sooner and reach sexual maturity faster. In contrast, country blackbirds begin their day traditionally, at sunrise, don’t rush, and sleep longer.

“Our work shows for the first time,” Helm concluded, “that when sharing human habitats, a wild animal species has a different internal clock.”

Her colleague on the study, Davide Dominoni of the Max Planck Institute for Ornithology, added that for city songbirds, “early risers may have an advantage in finding a mate and thus a greater chance of successfully producing offspring and passing along their chronotype—the time of day their body functions are active—to the next generation. Other research has shown that chronotypes are highly heritable, so the process of natural selection could mean that city birds are evolving to favor early risers.”

Tinkering with evolution, we subject our pets and plants (as well as the wild animals who live near us) to our manufactured schedules of light and dark, sleep and waking, toileting, exercise, and feeding. Seasonal time has given way to a chronicity which has its own intricately satisfying beauty and a certainty one rarely finds in nature. We’ve not only rigged clocks to slice our days into tiny even segments, and lit up the night with noble gases trapped inside glass, rewiring our own circadian rhythms in the process, we’re also resetting the rhythms of the planet’s other life forms.

In Aesop’s fable “The Town Mouse and the Country Mouse,” two cousins exchange visits, during which the city mouse turns down his nose at humble country fare, and the country mouse discovers that city life, while richer, is unbearably dangerous. I’d rather gnaw a bean than be gnawed by continual fear, he wisely opines. But thanks to us, today’s city mice are growing big brains to outwit the ambient dangers. Not just mice. According to researchers at the Bell Museum of Natural History at the University of Minnesota, we’ve caused at least ten urban species—including voles, bats, shrews, and gophers—to grow brains that are 6 percent larger than those of their country cousins. Heavens, smarter rats! That’s a scary thought. As we felled and planted over their woods and meadows, only the cleverest animals survived, by tailoring their diet and behavior to the human-dominated landscape. Those who did passed big-brained genes on to resourceful offspring. And they were the lucky ones. Not all plants and animals can evade us or evolve; only the most flexible endure.

To cope with urban life, some animals have even begun redesigning their bodies at a pace fast enough for biologists to track. On a flat, horizonless Nebraskan highway, Charles Brown will often pull over to inspect a fresh piece of roadkill, provided it’s a cliff swallow. Chestnut-brown-throated, with white forehead, pale breast, and long pointy wings, cliff swallows favor cliffs, their ancestral roosts. I’ve enjoyed watching aerobatic crowds of them barnstorming the cliffs of Big Sur, where their calls—banshees quarreling in high, squeaky twitters—mix with crashing surf.

But cliff swallows do need cliffs. These days, faced with city sprawl, they’re plastering their gourd-shaped mud nests onto buildings, beneath highway overpasses, and tucked into railway trusses and trestles, building up colonies of thousands on our concrete cliffs.

A behavioral ecologist at the University of Tulsa, Brown has been observing their gregarious social life for thirty years, traveling from colony to colony, and often passing birds killed in the maelstrom of traffic. He’ll stop and check for a leg band and perhaps collect the bird for research.

“Over time,” he says, “we began to notice that we were seeing fewer dead birds on the roads.”

A bigger surprise was the length of their wings. The roadkill birds had longer wings than the swallows he’d caught in mist nets. These two changes—fewer birds dying in accidents, and a difference in the wing length of dead versus living birds—led him to a startling conclusion. To cross the road safely, cliff swallows had to weave and dodge at speed, favoring those with the short wings of dogfighting jets. The unlucky swallows with long wings more suited to pastoral life died in accidents, leaving the short-winged swallows to breed and become dominant. All in just a few decades.

“Longer-winged swallows sitting on a roadside probably can’t take off as quickly, or gain altitude as quickly, as shorter-winged birds, and thus the former are more likely to collide with an oncoming vehicle,” Brown suggests. “These animals can adapt very rapidly to these urban environments.”

How should we regard the blackbirds, cliff swallows, and other animals that are evolving in such a snap because of our technology? Will they become new species? Or are they just new citizens of our age?

What makes nature natural? It’s a quintessentially Anthropocene question. Nature thrived long before cities did, long before we coated the Earth with an immensity of humans. Wild animals live among us. Our toil and our machines are entwined in their fate. Even our densest city is a permeable space, although we try hard to live a world apart. We decide the limits of the wild and where a city begins and ends. Suburban sprawl has replaced the overgrown buffers we used to have, transitional land between the two worlds. Now wild and urban animals encounter one another daily.

We cherish a strong sense of place, rich with memories. But other animals abide by a sense of place, too. Banding studies show that ruby-throated hummingbirds travel the same route every year, zigzagging to their favorite yard. A familiar pair of mallards comes to canoodle behind my house every spring. Countless other critters return to a special mating or nesting spot, and will continue trying, even if we fragment their world on a grand scale by installing the materials, plants, and animals we prefer. When we claim a patch of real estate, scent-marking it with our stuff, and purging it of wild animals, we presume the animals will bow out graciously. As sensitive tyrants, it rattles us when they don’t and try to resettle their once-cherished digs.

Citywise animals are mainly invisible to us, hunting at night or creeping in shadows, and if we do encounter them, they surprise us by being out of place. We forget that the animal kingdom is a circle of neighbors who often drop by unannounced. Even if the previous residents have skedaddled, or rerigged their schedules, new species may begin showing up like furtive relatives from who knows where. By the time you realize they’re not just visiting, they’ve shot down roots, claimed a little fiefdom, disturbed some of your neighbors, and added a tiny codicil to daily life. Not always a welcome one.

Before the 1990s, no one saw coyotes on the streets of Chicago. Now the city offers refuge to two thousand, which prefer parks, cemeteries, and ponds and generally flee from people. But some have been tracked crossing more than a hundred roads a day and moving into residential neighborhoods. Moose regularly pay house calls in Alaska, stomping into yards and onto porches, looking for grub. Giant antlers and all, they can leap chain-link fences. On many a golf course in Florida, alligators create an extra water hazard, and lakeside settlers know to keep their Chihuahuas indoors. Mountain lions forage in Montana cities; cougars stalk joggers in California; elk stroll through housing tracts in Colorado. When one Jacksonville woman lifted up her toilet seat, a water moccasin leapt out and bit her; another woman, in Brooklyn this time, found a seven-foot-long python in her toilet. Leopards prowl the streets of New Delhi by night. In the Royal Botanic Gardens, in Melbourne, Australia, endangered gray-headed flying foxes built a colony of thirty thousand bats, drawn to the garden by all the cultivated native plants: eighty-seven healthy tree species with the fruit they preferred, a year-round oasis. Why risk the outback? And, maybe strangest of all, prairie dogs, those ground-dwellers of the open range, have begun digging their towns in our cities.

However, as it’s beginning to dawn on us that there’s no sharp line between the untamed and the built up, more people are trying to help wayward creatures find their way through our mazes.

When a lost eight-month-old coyote strayed into downtown Seattle, he became confused by the streets and buildings and grew frightened and disoriented. Dashing for what must have looked like a dark haven, he ran through the open door of the Federal Building, skidding on polished floors and around narrow hallways, bumping into glass, walls, and people in a panic. Then he spotted a cave to hide in—an open elevator—and darted inside, and the doors closed. For three hours, the poor creature paced that metal box until people from the state fish and wildlife department trapped him and set him loose outside of town.

It’s surprising how disruptive even a slow, lowly terrapin can be. One June day recently, more than 150 diamondback turtles scuttled across Runway 4 at JFK, delaying landings, halting takeoffs, foiling air traffic controllers, crippling timetables, and snarling air traffic for over three hours. Cold-blooded reptiles they may be, but also ardent and single-minded. Never mess with a female ready to give birth.

Graced by beautiful rings and ridges on their shells, diamondbacks look like a field of galaxies on the move. We think of the shell as a lifeless kind of armor, but it’s actually attached to their nervous system, not just a bulwark but an integral part of their inner world. They inhabit neither freshwater nor sea but the brackish slurry of coastal marshes. Mating in the spring, they need to lay their eggs on land, so in June and July they migrate to the sandy dunes of Jamaica Bay. The shortest route leads straight across the busy tarmac.

Don’t the plucky turtles notice our jets? Probably not. Even with polka-dot necks stretched out, diamondbacks don’t peer up very high. And unlike, say, lions, they don’t have eyes that dart after fast-moving prey. Ploddingly slow, they abide by seasonal time, so the jets probably blur into background—more of a blowy weather system than a threat. But planes generate a lot of heat, and the turtles surely find the crossing stressful. Not to mention the roundup. After a little light banter between pilots and air traffic controllers, Port Authority crews descended, scooping turtles into pickup trucks and ferrying them to a nearby beach.

“We ceded to Mother Nature,” said Ron Marsico, a Port Authority spokesman. “We built on the area where they were nesting for generations, so we feel incumbent to help them along the way.”

Mounted on the shoreline of Jamaica Bay and a federally protected park, indeed almost surrounded by water, JFK occupies land where wildlife abounds, and it’s no surprise that planes have collided with gulls, hawks, swans, geese, osprey, and even milky-winged snowy owls (an influx from the Arctic). Or that every summer there’s another turtle stampede, sometimes creating lengthy delays. As a private pilot, I remember well how airports used to treat animal “hazards”—at gunpoint. It’s heartening these days to find other solutions, from relocation to relandscaping, with canny coexistence the preferred option.

In my town, we’re blessed by lots of wild animal visitors, from star-nosed moles and eagles to otters, wild turkeys, foxes, and skunks. White-tailed deer are so numerous that they qualify as residents. Last week I was shocked to see a coyote toe stealthily up to the bird feeder outside my kitchen window, below which sat a plump seed-gobbling rabbit. When I opened the window to address the coyote, he turned tail and trotted into the tall grasses lining the driveway. Yesterday evening I caught sight of him once more, this time as a streak of yellow dots and dashes weaving through the bushes in my backyard. It took a moment for my brain to decode the pattern, and another moment to start worrying about the two baby rabbits eating clover on the lawn.

On a rainy morning so gray a dappled mare could get lost in it, my village held a public hearing to decide the fate of our local deer. Over a hundred residents spoke out against the proposed amendment to the firearms law, which would invite wildlife exterminators to bait and shoot the deer as long as they were at least five hundred feet from houses, schools, and yards. Lured with corn, the deer would be killed by high-powered bows and rifles. Because ricocheting bullets and arrows are possible, the village plans to take out liability insurance in the multimillions. If this sounds like a dangerous and extreme solution to the deer problem, you’ll understand the passion of the protesters.

Homeowners defended shooting the deer, which they regard as vermin. For them, it’s either the deer or the landscaping. Several gardeners conceded that deer had eaten many of their plants, but argued in favor of deer fences, not gunfire. One man grew tearful as he implored the board to live in harmony with nature. A psychologist accused the board of “groupthink,” in which deer have become a new demonized minority. Mothers worried over the safety of children walking home from school or playing outside amid stray bullets—and also over the psychological damage of witnessing the death of wounded deer.

One little girl asked her mother: “If they shoot all the deer, how will Santa deliver the presents?”

Another mother said that in her child’s elementary school, peaceful arbitration was being taught. She asked: “How can I begin to explain the hypocrisy of grown-ups solving their deer problem by hiring killers to gun down the deer?”

“There are so many deer fences—it’s like living in a war zone!” a kill-the-deer man cried. To which a save-the-deer man replied: “And you think snipers firing bullets around the village for the next ten years will be less like a war zone?”

Most protesters pleaded with the board to give fences and sterilization a good chance. Others argued that the board was legally bound to follow majority rule and should start shooting. Some debunked long-held myths about deer and Lyme disease (the white-footed mouse carries the agent, and killing the deer won’t banish the Lyme tick, which feeds on twenty-seven species of mammals, including cats and dogs). Or the idea that deer cause the most traffic accidents (speeding and alcohol do). Or that birth control methods fail (immuno-contraception has worked in national parks). Contraception is expensive, but so is hiring sharpshooters every year and paying for liability insurance.

What struck me as some kill-the-deer people spoke was the tone of dread and loathing, a panic about being invaded by wildness and roughly overtaken by the chaotic forces of nature. It’s as if we weren’t talking about the deer at all, but about what Freud called the Id, that wild demon of the psyche we keep just barely in check, and which otherwise would be slobbering, rutting, and killing all the time. What if its sheer feral exuberance took charge? Soon, neighbors’ yards would teem with tall gangs of unruly weeds. Or they might stop raking the leaves, and then clots of color would smother everyone’s lawn. Four-legged predators inspire the most panic, but if wild turkeys and deer can find their way into suburbia, can fiercer animals be far behind, ones with fangs and teeth, whose red eyes pierce the night?

Yet, at the same time, something deep inside us remembers being accompanied by animals. There was a time not very long ago when cows, goats, horses, and other animals slept indoors beside us, or at least shared the same roof. In some parts of the world, they still do. But most humans have pitched their plaster-walled tents in cities and suburbs, crowding out animals, especially wild animals, and pushing them farther and farther away, to the perimeters of daily life.

In the mists of the mind, we’ve lost our time-honed knack for coexisting with other creatures. We erect walls to keep nature out and take pride in scrubbing dirt and dust from our homes. Then we adorn our houses with bouquets of flowers, and scent absolutely everything that touches our lives. We seat windows in our walls, install seasons (air-conditioning and heat), and fasten at least one noonday sun in every room to shower us with light. Confusing, isn’t it?

Even indoors, we surround ourselves with pet companions who help bridge the apparent no-man’s-land between us and nature, between our ape-hood and civilization. A dog on a leash is not really tamed by its owner. It’s a two-way tether. The owner also extends himself through the leash to that part of his personality which is pure dog, the part that just wants to eat, sleep, bark, mate, and wet the ground in joy. We’ve all felt it.

Nature is dynamic and haphazard, and so are we—not a serene combo. Maybe it’s one that’s best described in paradoxes such as organized chaos, but we’re not beings who feel comfortable with paradox. Paradox tugs the brain in opposite directions, confounds our quest for simple truths, and throws a monkey wrench into the delights of habit. Faced with paradox, our brain automatically slaves to solve or squash it. And so here we find ourselves, disorderly beings, blessed or cursed with order-craving minds, in a disorderly universe we’re fully capable of bringing increased order to—but not absolute order, and not forever.

I SOMETIMES WONDER what Budi would make of our metropolitan jungles. Just like city monkeys the world over, leaping across rooftops, shimmying down drainpipes, nesting at night in the canopy of iron fire escapes, Budi would adapt to the hard surfaces of city life. On school playgrounds, children might see him using the monkey bars and jungle gym with a simian ease they only dream of. He’d find fruit to steal on many corners, densely treed parks where he’d mingle with the other species of great apes, many his own size and mental age, though physically much weaker and easily hurt. Some of the same urban animals that scare us would scare him: bears, coyotes, mountain lions, and such. Would he regard the city as another natural landscape, with blockish mountains, vast herds of humans, and their many watering holes and bazaars? Most likely he would. He’d not only adapt, he’d change his behaviors to suit the new realm, just as so many other urban animals (including us) have been doing with surprising success. It seems obvious that a city, or a cage in a zoo, is not what we mean by a “natural” environment, but in the Anthropocene, it can be hard to say what is.

IF WE DON’T want even more animals living with concrete sidewalks and feeding off human garbage, we must intervene. At this point, preserving the wild is not just a matter of hands-off, as traditional conservation decrees, but also the hands-on of creating other kinds of habitats, such as wildlife corridors. In my mind’s eye, I see flashes of the tiny green rainforest on Brazil’s Atlantic coast, an Amazon-like realm where the highest concentration of endangered birds in the Americas and the remaining golden lion tamarins cavort in small pristine Edens atop mountains riven by highways and towns. A dozen years ago, when I traveled there as part of the National Zoo’s Golden Lion Tamarin Conservation Program, another team was busy building a wildlife corridor, Fazenda Dourada, to link up the mountaintops and extend the birds’ and tamarins’ range. Not far away, snaking from Argentina all the way up into Texas, the Jaguar Corridor has gifted the scarce, almost mythic spotted cats with space to roam. It only seems fitting that, having rent the fabric of the wild, we at least stitch some green sleeves back together so that animals can rejoin their kin and migrate along ancestral routes. Around the globe countries have been avidly building these links, prompted by a fruitful mix of compassion and self-interest. The United States has some lengthy wildlife corridors, such as the Appalachian Trail, a thousand-foot-wide greenway running two thousand miles along ridgelines from Georgia to Mt. Katahdin in Maine. In India, the Siju-Rewak Corridor protects 20 percent of the country’s elephants from collisions with human civilization and its toys. Kenya has created Africa’s first elephant underpass, a tall tunnel beneath a traffic-snarled major road, which gives two elephant populations long divided by human dwellings a chance to migrate, mingle, find mates, and avoid terrified humans or terrifying traffic.

In Europe, the Green Belt Corridor will soon allow wildlife to ramble all the way from the tip of Norway through Germany, Austria, Romania, and Greece, deep into Spain, following ancient trails while searching for food, mild weather, and safe birthing grounds. Linking twenty-four countries and winding past forty national parks, it spans nearly 8,000 miles, some of it following the old historical line of the Iron Curtain, the 870-mile-long chain of fences and guard towers that once clawed the length of Germany, separating the East from the West. After reunification, what was once “no man’s land” lingered as a lifeless scar, until conservationists began reshaping it into a winding nature corridor. Transformed again by human hands, the blue-ribbon path now proclaims tolerance, not repression. The refuge naturally includes many different habitats, from sand dunes and salt marshes to forests and meadows. Ditches that kept vehicles from crossing are being crisscrossed by endangered European otters. Eurasian cranes, black storks, moor frogs, white-tailed eagles, and other stateless species are mingling safely.

In France, China, Canada, and other countries, more corridors are offering tunnels, underpasses, viaducts, and bridges to help wildlife cross their native range, while protecting them from vehicles and us from them. In the Netherlands, six hundred such over- and underpasses allow roe deer, wild boar, European badgers, and their kind to navigate around everything from railway lines to sports complexes. All this adds to a renewed sense of kinship: animals trotting, shuffling, climbing, and winging safely among us, visibly a part of life’s seamless web. Like any other close relationship, living with wildlife requires compassion, compromise, and seeking solutions that will benefit all. If peaceful coexistence were easy, there would be no divorce or political strife, only households and empires of domestic tranquillity.

Like many of my neighbors, I fence in the deer’s favorites: roses, rhododendrons, day lilies, hostas. In the front yard, I plant beauties the deer reject—iris, peony, cosmos, allium, false indigo, foxglove, monkshood, bee balm, bleeding hearts, sage, daffodil, veronica, poppy, dianthus, and many more—though they still find a lot to munch on. Instead of fencing in the whole property, I’ve left a corridor for the deer, foxes, coyotes, and other critters alongside a creek that ultimately winds north to Sapsucker Woods.

I enjoy sharing the neighborhood with so much wildlife, a kinship that greatly enriches my life. I’d rather the groundhogs didn’t burrow under my study, and the raccoons didn’t play chopsticks on the bathroom skylight and stare down with bandit eyes—but I haven’t evicted them. I relish the swoop of brown bats at sunset, elegant and enchanting little creatures that eat hundreds of insects every night. Sex-crazed frogs and toads party in the backyard, making a ruckus that can drown out TV or movie watching, but I find their ballyhoo a hilarious part of summer’s jug band music. Plying the water below them and adding to the fiendish din are water boatmen, dark copper insects with olive stomachs who swim on their backs, paddling with two oarlike legs, while carrying a silvery bubble of oxygen to breathe as if they were early argonauts. Though small (¼"–½"), they’re adjudged the loudest animals on Earth relative to body size. During sultry summer nights, their singing penises (scrubbed fast over the stomach, washboard-style) can reach 99.2 decibels. That’s louder than standing near a freight train, louder than sitting in the first row of a concert hall during a thunderous symphony, even if the water muffles some of their clamor. I’m impressed by the platoon of male spotted newts doing he-man push-ups on the driveway and atop the fence, hoping to make females swoon. I’m delighted when a flicker beats heavy metal tunes on the stop sign—or even if he repeatedly rings my doorbell, as happened one summer. I enjoy spotting red-crested pileated woodpeckers, big as Cheshire cats, whacking the stuffing out of trees. Delving squirrels mean I have to plant bulbs under chicken wire, but I’m amused by their antics. I’m a bit sad I don’t have inquisitive black bears to contend with. Deer are the largest animals to pay house calls, and like the dogfighting hummingbirds, tree-climbing chipmunks, and rabbits engaging in an odd tournament of hopping jousts, they arrive unbidden but are welcome emissaries from the natural world.

Each year, I line up behind a dozen cars on a busy highway as a caravan of Canada goose chicks waddles across in a single line between guardian geese, apparently unfazed by motorized honking and the occasional impatient driver. Most people, like me, sit quietly and smile. Like the turtles at JFK, they remind us that, even with egos of steel and concrete plans, we’re easily humbled by nature in the shape of snowflakes, goslings, or turtles—all able to stop traffic. They also remind us how conflicted we really are about nature.

IS NATURE “NATURAL” anymore? Of course. But it’s no longer indisputably other. The earth scientist Erle Ellis has invented the term “anthrome” to refer to the “hybrid human-natural systems that now dominate Earth’s surface.” From our small vest-pocket gardens to our giant wilderness areas and parks, nature now reflects our preferences, and one of our most cherished ideas about nature is that nature should be human-free. So we have evicted the indigenous peoples from lands we wished to designate national parks, from the United States’ Yellowstone and Grand Canyon to Cameroon’s Korup National Park and Tanzania’s Serengeti, even though tribes may have lived there for ages, and coexisted to an inspiring degree with the environment.

For Europeans, the word “wilderness” used to mean a wild, barren, chaotic place full of plight and mischief, where it was simple to lose one’s bearings or mind. It’s easy to forget how ugly nature often seemed to people before Romanticism reexplored the ruggedness of natural beauty. Early-nineteenth-century writers found wildernesses grotesque—not just dangerous and obstructive and rife with bloodthirsty animals but actually a vision of evil. Now the idea of wilderness is just the opposite: a sanctuary, an emblem of serenity, a view of innocence.

Nature is always mutating, on a large and small scale—the lavish suns of summer, the dragonfly’s seasonal demise. Those regular turnovers can become humble as old clothes, nothing to raise a ripple of awareness, let alone concern, and too rarely a sensory cascade. The romance with nature—childhood—gives way to the companionship stage, a time of purposeful beguiling, when it takes more to capture your attention. But a nonmigration of geese, a neverthriving of crops, a carillon of snowdrops blooming a month too early, ripe berries way out of season, a bay full of lobsters ankling off to the north, the weird absence of winter—these give one pause. Our newest idea of nature is one of vulnerability, a vast, sprawling, interlaced organism growing weaker.

At precisely the moment we’re achieving unprecedented feats and ruling the planet on a grand scale, we’re discovering that our future as a species may suffer as a result. Nature isn’t separate from us, and part of our salvation as a species depends on respecting, if not rejoicing in, that simple companionable truth.

The Slow-Motion Invaders

Named P-52, as if she were a bomber or a precious fragment of papyrus, the Burmese python recently found in the Everglades weighed 165 pounds and stretched 17 feet in length, setting a local record (not a world record—that’s held by a 403-pound, 27-foot-long python residing in Illinois). A tan beauty, with black splotches that resemble jigsaw puzzle pieces, dry satiny skin, and a body like a firm eraser, P-52 had a pyramidal head, a brain surging with raw instinct, tiny black Sen-Sen eyes, and a mind like a dial tone. In her heyday, she could squeeze the life out of an alligator or a panther. And she was pregnant.

Standing shoulder to shoulder at the dissecting table, amazed University of Florida scientists uncovered eighty-seven eggs in her womb. Not all the hatchlings would have survived. But with such fecundity it’s easy to understand the flourishing of pythons throughout the southern region of the Everglades—slipping through the sawgrass, sibilant as sassafras, slanting up to their prey, and then—slam!—seizing hold with back-curving teeth, crushing and slowly swallowing every morsel.

No one knows precisely how many pythons inhabit South Florida, but reliable estimates run to thirty thousand or more. Over the last ten years, snake wranglers removed 1,825 pythons from as far north as Lake Okeechobee and as far south as the Florida Keys. In the picturesque, if amusingly named, Shark Valley (no sharks, a valley only a foot deep) in the heart of the Everglades, visitors may glimpse a python plying the river of grass, or even wrinkling across the road. Pythons will also be busy hunting, sun-swilling on the canal levees, mating (in spring), coiling around their eggs and trembling their muscles to incubate them, occasionally wrestling with alligators, and absorbing warmth from still-toasty asphalt roads at night.

Alas, they’ve vanquished nearly all the foxes, raccoons, rabbits, opossums, bobcats, and white-tailed deer in the park; also the three-foot-tall statuesque white wood storks. A survey conducted between 2003 and 2011, and published in the Proceedings of the National Academy of Sciences, reported that raccoons had declined 99.3 percent, opossums 98.9 percent, and bobcats 87.5 percent. Marsh rabbits, cottontails, and foxes completely disappeared. Last year, one python was found digesting a whole 76-pound deer.

Where did all the pythons—native to India, Sri Lanka, and Indonesia—come from? Some were wayward pets or hitchhikers in delivery trucks. Others escaped from ponds overflowing in heavy rains, from pet stores during hurricanes, or from international food markets. They hid in foreign packing materials for plants, fruits, and vegetables, or clung to boat hulls or propeller blades. Some may have freeloaded in the ballast of large ships, which take on water and who-knows-what aquatic species in a foreign port, and release alien life forms when they reach their destination. Others sneak a ride on board globe-trotting pleasure or military planes.

Many invasive life forms arrive legally, as desirable crops or companion animals that help to define us or just strike our fancy. Burmese pythons have become popular pets in the United States, credited with a pleasant personality, as snakes go. They’re sometimes bred as stunning yellow-and-white mosaics—like the one Britney Spears slipped around her shoulders and slither-danced with at the MTV Video Music Awards in 2001. But many python owners, chastened by the twenty-year commitment, or alarmed by how quickly the reins of power can shift as the snake grows, turn them loose in the Everglades, assuming it will offer an Edenic home. It does. Undaunted by anything smaller than a mature alligator, they eat everything with a pulse, ravaging the whole ecosystem. Native species haven’t yet evolved to resist or compete with them, the strongest toughs around.[10]

OF COURSE, MOST of us humans are transplants, too, perpetually bustling between cities and taking familiar plants and animals with us—by accident or by design—without worrying much over the mischief we may be unloosing. We are like witches, leaning over the cauldron of the planet, stirring its creatures round and round, unsure about our new familiars—not wildcats, but pythons?—and waiting to see what on Earth may bubble up next.

Accidental hobos, exotic species travel with us everywhere. A list of known invasive species would fill pages, and their handiwork volumes. Because, like the Burmese python, they can wreak havoc with an ecosystem, we scorn them as marauders, as if it were their fault. But most often we’re the ones relocating the planet’s life forms.

Invasive species may carry hobos of their own, contagious ones we’re not immune to. When a San Francisco woman’s pet boa, Larry, fell ill recently, scientists studied the genome of boas and to their shock discovered a genetic mishmash of arenaviruses, which spawn such human nightmares as Ebola, aseptic meningitis, and hemorrhagic fever. It’s entirely possible, they surmise, that Ebola began in snakes and spread to humans. Or that, somewhere along the evolutionary road, snakes became vulnerable to Ebola, just as we did. Now we know that reptiles can harbor some of the world’s deadliest human viruses, yet we still ferry them from one locale to another.

Pythons aren’t the only brawny Floridian invaders. In Cape Coral, monitor lizards—which can reach six feet long—threaten the protected, and altogether winsome, burrowing owl. Gambian pouched rats are overrunning Grassy Key. Cuban tree frogs devour smaller native frogs. Giant African snails dine on five hundred different plants. Jumbo green iguanas are driving the Miami blue butterfly toward extinction. And monk parakeets flock across the Florida skies, flat-nosed as aging prizefighters, making otherworldly shrieks that sound like people prying the lids off cans of motor oil. Unfortunately, their large colonial nests can damage residential trees and electrical power lines, and not everyone is a devotee of squawks, so they’re regarded as a nuisance. Florida boasts more invasive species than anywhere else on Earth, from wild boars and Jamaican fruit bats to squirrel and vervet monkeys, nine-banded armadillos, and prairie dogs.

The same thing can happen in freshwater, and the Finger Lakes now teem with zebra mussels (Russian natives) that clog boat engines and water intake pipes and weigh down buoys. In Tampa Bay, green mussels (New Zealand natives) are smothering the local oyster reefs. Asian carp are turning the Great Lakes into their private dining room. With great relish, the rainbow-sheened Japanese beetles are snipping rose leaves into doilies. Although the Nile perch was introduced into Lake Victoria to appear on the tables of locals, no one counted on its predatory gusto, and it’s decadently feasting on a hundred species of native fish.

We’ve been wantonly shuffling life forms for tens of thousands of years. Migrating bands of Homo sapiens carried plants, animals, and parasites with them on their travels, and ancient texts often speak of importing exotic delicacies and species from foreign lands. Vagabond species travel in our luggage, cuffs, and cars—shadowing us around the block and around the world. During the seventeenth- and eighteenth-century voyages of exploration, along with ideas and goods we spread vermin and disease. We colonized every continent and all but the most extreme ecosystems, reconfiguring them at speed. Just breezing through our lives—hiking across a meadow, commuting to work, flying or sailing overseas—we keep rearranging nature like a suite of living room furniture.

So invasive species have been running riot for ages, some a plague and a nuisance, others a delight. We’ve transplanted a great many plants and animals on purpose, for their beauty, novelty, taste, or usefulness—from starlings and poison ivy (a nonallergic European found it pretty and took it home with him) to exotic reptiles and azaleas. Charmed by the climate and organisms at their new locale, they’ve taken hold, sometimes fiercely (as is the case with eucalyptus, bamboo, and Indian mongooses), to the distress of local species and human residents. People love their English ivy, Norway maple, bullfrogs, Japanese honeysuckle, oxeye daisies, St. John’s wort, dog roses, Scots pine, etc. In contrast, such alien invaders as African bees, tiger mosquitoes, fire ants, water lettuce, burdock, lampreys, loosestrife, bamboo, kudzu vine, and dandelions (which apparently accompanied pilgrims on the Mayflower) are scorned, cursed, and uprooted.

We insist that invasive species don’t belong in wilderness, but native ones do—even if they’ve died out. Inspired by that notion, we’ve reintroduced wolves into Yellowstone, moose into Michigan, European lynxes into Switzerland, musk oxen into Alaska, Przewalski’s horses into Mongolia and the Netherlands, red kites and golden eagles into Ireland, cheetahs into India, black-footed ferrets into Canada, brown bears into the Alps, reindeer into Scotland, northern goshawks into England, Bornean orangutans into Indonesia, condors into California, giant anteaters into Argentina, Arabian oryx into Oman, peregrine falcons into Norway, Germany, Sweden, and Poland—and a great many more. At the same time we’re destroying some ecosystems, we’re busy recreating many others.

People may talk about rebalancing an ecosystem, but there is no perfect “balance of nature,” no strategy that will guarantee perpetual harmony and freedom from change. Nature is a never-ending conga line of bold moves and corrections. Hence the continuing debate about whether or not the Everglades should be python-free or allowed to evolve into whatever comes next. Ever since the 1920s, we’ve been transmogrifying Florida swamps into houses. So the real question is what sort of pocket wilderness we prefer.

I’m of two minds about this case. On the one hand, I don’t want to disturb the dynamic well of nature. Habitats keep evolving new pageants of species, and we shouldn’t interfere. Yet I also sympathize with those who argue that we should capture the pythons in the Everglades and allow the ecosystem to return to its admittedly idealized state, where foxes, rabbits, deer, and a host of other vanishing life forms may flourish. We’re losing biodiversity globally at an alarming rate, and we need a cornucopia of different plants and animals, for the planet’s health and our own. By introducing just one predator into a beloved habitat, we’ve doomed a shockingly large segment of species and all those that depend on them.

The tug-of-war we secretly feel between our animal and human natures is part of what makes us endearingly compassionate, and mighty strange primates. Unlike other animals, we care deeply about scores of life forms with whom we share the planet, even though they’re not family members, not even species members, for that matter, not possessions, and not personal friends. We care abstractly about whole populations we may not have seen firsthand, determined to help fellow creatures survive. We feel a powerfully mingled kinship.

Whatever interventions or restorations we might plan, our unplanned intervention, in the form of climate change, is rearranging habitats in ways we can’t begin to control, spawning migrants everywhere. We may notice more pine or spruce beetles this year, or fewer familiar butterflies poised like pocket squares atop the flowers, or thinner fire-crisped forests with dusty winds and jaw-dropping heat. We may wonder where all the slender-necked corncrakes have gone. We may obey the rules and not water lawns or wash cars or let the faucet run while brushing teeth. But we may not connect the dots and link less water and missing butterflies and corncrakes to early spring and snowpacks melting too soon, leaving little water for parched forests during the long torrid summer, when already weakened trees face an armada of beetles and incendiary drought.

This is not so much a vicious cycle as a carelessly torn fabric. You notice a ripped seam, and though you may procrastinate about fixing it, it annoys your senses, it picks at your awareness, something isn’t as whole. The foxes have moved north, there are new snakes in the yard, field mice have either waned or multiplied to Pied Piper of Hamelin status, West Nile virus is slaying the local crows, and you spotted something long with eyes and scales swimming in the canal. Lured by the warmer, north-spreading swamps, alligators have begun slithering up from Florida into North Carolina. In time, they may well become native to Virginia, maybe venturing as far as Virginia Beach, with some trailblazers swimming up the Potomac to D.C.

One keystone species, plankton,[11] at the heart of the ocean food chain,[12] tells a tale of the changing times. Tiny shrimplike flagellates in the trillions, without a thought among them, they’re barely visible to us and seem far too weak to act as a keystone, without which hazel-waved ocean life would collapse. But they are one of the largest biomasses on Earth, drifting everywhere on the currents like pointillist clouds.

In Arctic waters, where polar bears travel the corridors of sea ice with their young, resting and hunting, and seabirds nest on icy cliffs, flying to fish through cracks in the ice, seals give birth and raise their young atop the floes. Walruses ride on magic carpets of ice to fish farther afield. With warmer water, there are fewer icebergs where algae cling, and fewer algae-eating plankton as a result. According to a recent study published in Nature, worldwide levels of plankton are down 40 percent since the 1950s, which means less food for the plankton-feeding fish, birds, and whales.

Less plankton leads to fewer krill, tiny crustaceans whose numbers have also plummeted, and fewer petite Adélie penguins, which feed on krill and squid in Antarctic waters at the other end of the globe. Untidy masons of the penguin world, Adélies build nests of stones along gently sloping beaches and raise fluffy, brown, yeti-shaped chicks in those miniature craters. When I visited one large, squawksome colony twenty years ago, stones were a precious commodity. But, according to the ornithologist Bill Fraser, that Adélie population has dropped by 90 percent in the past twenty-five years. With so few couples courting, there are stones abounding, but less food for the orcas (killer whales) and leopard seals that prey on the penguins.

Yet the Anthropocene (like nature itself) rarely tells simple stories. In Alaska, our bestirring of the weather is good for the nearly extinct trumpeter swans, who are using the longer summers to feed and raise their young. Orcas will also profit from the warmer waters. As Arctic seam ice shrinks to a record low, undulating orca shipping lanes open up across the pole via the once-fabled Northwest Passage, changing the ecology of the northern ocean. The melt allows the orcas to widen their range and catch more of the white “singing” beluga whales, the canaries of the ocean, and the unicorn-tusked narwhals, two of the orca’s favorite meals. But both the belugas and the narwhals are endangered.

How astonishing it is that just one warm-blooded species is causing all this commotion. Creating hives of great megacities and concrete nests that tower into the sky is impressive enough. But removing, relocating, redesigning, and generally vexing and bothering an entire planet full of plants and animals is another magnitude of mischief beyond anything the planet has ever known. The first is just brilliant niche building, something other animals do on a much more modest scale. For instance, beavers fell trees and dam up streams to create ideal ponds for their underwater huts, and in the process some flora and fauna are dislodged. But no other animal widens its niche to disturb every life form on every continent and in every ocean.

The addled climate is boosting some species and harming or extinguishing others, and not in faraway places, but close to home, in signposts as plain as the jamboree of Canada geese on your lawn. This news of climate change isn’t accusatory, jargon-ridden, arguable, or even verbal. It’s local and personal when eagerly awaited butterflies—the ones that captivated your parents, you, and your children every Good-Humor-jingling summer you can remember—have fled. Some things are more visible in their absence.

In England, the once-rare Argus butterfly has been extending its range northward over the past thirty years, and altering its diet in habitats free of its natural enemies (parasitoids). It’s a marvel with brown wing tops fringed in white, and bright-orange eye dots; the underside is paler brown with black and white eye dots plus the orange. The North Country nurse, leaving her local pub, won’t see her favorite winged pub-crawlers flitting across the meadows. Until she visits her sister thirty miles farther north, where the rare beauty is now plentiful. How come you now get the butterflies and I don’t? she may be thinking with a touch of sibling eco-rivalry. Parasitoids used to finding Argus caterpillars on certain plants haven’t kept up with Argus’s northward migration.

Imagine if you woke up one morning and discovered that the restaurants across the street, the nearby deli and groceries—in fact, all your usual food pantries—had moved several hours north during the night. Would you make long tiring shopping trips, change your diet, or follow the food and resettle in the north? Like our hunter-gatherer ancestors, you’d probably pack up and follow the herds. (Our herds may lie motionless on shelves these days, but we’re still out there hunting and gathering.)

The Spanish ornithologist Miguel Ferrer estimates that around twenty billion birds of many species have altered their migration pattern because of climate change. “Long-distance migrators are traveling shorter distances; shorter-distance migrators are becoming sedentary,” he reported at a conference of two hundred migration specialists. “The normal summer temperature in your city twelve months ago is now normal four kilometers further north. It doesn’t sound like a lot, but that’s twenty times quicker than temperatures changed in the last ice age.”

An Audubon Society study found that roughly half of 305 species of North American birds are wintering thirty-five miles farther north than they did forty years ago. The purple finch is wintering four hundred miles farther north. Birds are fun to watch and beautiful, of course, but they’re also essential pollinators, seed dispersers, and insect eaters whom we need to help crops and ecosystems flourish.

It’s not always easy for birds to migrate in our citified, fragmented landscapes. Some species, fooled by warm weather into traveling too early, arrive in new environs before the food is sprouting in the fields. Once upon a time corncrakes filled the skies from northern Europe to South Africa with long-necked speckled charm and hoarse calls, nesting in field edges, or in dense vegetation and grasslands. As we’ve mown those fields to plant crops, corncrakes have lost their foothold and become scarce. Fortunately, through the synchronized efforts of fifty countries, from Belarus to Tasmania—such tactics as asking farmers not to mow their grasslands until after the chicks have fledged—corncrakes and their tottery black young are making a comeback.

There’s often little harm done by nudging plants and animals to new locales. That’s how we (the most successful invasives of all time) came to settle the continents, planting apples, peaches, horses, and roses. Only crab apples are native to North America. The sweet crisp honey-scented apples we wait for all summer, the fleshy Red Delicious we shine on our jeans, and the 7,500 other cultivars, each with its own taste, fragrance, crispness, and uses—all are invasives, and we’ve bred them like show dogs to taste, feel, look, cook, and smell the way we prefer. Since I’m an apple maven, I’m grateful for two old tart apple trees growing in my backyard.

I also find horses a wonderful addition to the North American landscape, even though I know they’re an invasive species that arrived on Spanish ships and adapted to the vast grassy habitats. It’s a mystery how this happened, but if we look at one instance—the wild ponies on the East Coast barrier islands of Chincoteague and Assateague—there are intriguing theories. Did pirates turn horses loose to graze while they were off looting, and return to find they’d vanished into the dense thickets and woods? Did seventeenth-century growers, who imported European horses, decide to pasture them on the island to avoid taxes, and discover that some wandered off to begin a herd? Did a Spanish galleon, bound for the English colonies, encounter a hurricane and break up on the island, where local Indians came to their rescue, but the ponies ran free? Did a boatload of Spanish horses, blinded for work in the mines, sink in a hurricane, and the terrified horses, despite the raging storm and their blindness, somehow manage to swim to shore? No one knows.

The ponies’ ancestors faced poor food, scorching summers and cold damp winters, sandpaper winds, relentless mosquitoes, and cyclical storms. In response they grew thick furry coats and learned a host of survival skills, such as sensing a drop in barometric pressure, seeking shelter in hilly areas, and huddling together with their rumps facing the high winds. As a result, only the fittest and smartest ponies survived, and their genes live on in the current herd, which is vigorous, canny, and well adapted to the rigors of a maritime landscape.

I may be able to trace my beloved rosebushes, which I raise organically, tend minimally, and almost never count, back thirty-five million years to fossils, or five thousand years to the Chinese gardeners who first dreamt of breeding them. They’re not native to North America either, but also highly successful invasives, which ran wild to the surprise and merriment of settlers.

Chinese mitten crabs may be destroying the San Francisco Bay habitat, but European green crabs are helping to revive the ecosystem in the salt marshes of Cape Cod. We’re restoring prairie ecosystems by reintroducing the grasses that used to fan slowly in the summer haze, and reclaiming wetlands by diverting streams and planting native flora. When we do, of course, it changes the climate and the migration patterns of birds and insects; some animals find a new home, while others decamp. In most cases, the ecological restoration is successful, but we sometimes get it wrong.

The southernmost of the Mariana Islands, about 1,500 miles south of Tokyo, Guam has been a U.S. dependency since the Spanish–American War of 1898. People think of it mainly as a military base, but it is also a lush tropical paradise. Yet at dawn all a visitor hears is an eerie silence, no birdsong, because most of the native birdlife has gone extinct. What’s been causing the extinction? Pesticide poisoning? Habitat destruction? Exotic disease? It took scientists years to figure it out. The answer is one pregnant Indonesian brown snake that slithered off a cargo ship in 1949. The nocturnal brown tree snake is an arboreal predator, up to eleven feet long, and poisonous. Equally happy in forests and on rocky shores, today the snake has multiplied into the hundreds of thousands. Birds evolved on Guam with no predatory snakes, and so most of the forest birds have been devoured, along with native reptiles, amphibians, and bats. The flightless Guam rail survives only in captivity, rescued in a last-ditch effort to save the species by starting a captive breeding program on Guam and in some mainland zoos, so that it doesn’t go the way of the Guam flycatcher, a species once unique to the island. Because birds were the chief seed-spreaders of native fruit trees, those are vanishing, too, and the island is aswarm with forty times more spiders, which the missing birds used to hunt.

The same fiddling with evolution can happen on much larger islands. In Australia, cane toads—native to the Americas, from south Texas to the Central Amazon basin—were imported as assassins to eat the plague of cane beetles, which they did with rousing success. In their native habitat, cane toads can grow as big as catchers’ mitts and weigh five pounds. In their new home, they also evolved longer legs to cross the vast outback. Only big-mouthed snakes could swallow the poisonous toads, and those snakes died in the process, leaving their smaller-mouthed, toad-shy cousins to pass on their genes. As a result, Australian snakes began evolving smaller mouths.

Sometimes we breed and move animals around the landscape to save their species from extinction. In Wild Ones, Jon Mooallem writes about his experience with Operation Migration, where endangered baby whooping cranes are hatched in incubators and taught wild crane behaviors, including how to migrate, and then are led thousands of miles by crane-suited humans flying ultralights. “This work,” Mooallem writes, “this wholesale manufacture of wild birds by human beings—turns out to be so ambitious, tedious, and packed with perplexing arcana that, after ten years, it’s hard for those who have given their lives to the project even to agree on how well it’s working and what they should do next.”[13]

Usually, however, we breed and transport animals not to save them but to suit ourselves: domesticating dogs, cats, and even pythons as pets, enslaving horses and oxen for work, or drafting a cavalcade of creatures—from camels and horses to pigeons and bats—to fight beside us in our bloodiest wars.

“They Had No Choice”

When the life-size horse puppet first appears onstage in War Horse, its neck rippling and ears twitching in startlingly lifelike ways, it takes a moment to figure out what humans are doing inside a see-through horse. But as the puppeteers brilliantly animate the tendons and muscles, it makes sense to the inner shaman inside us, the being who identifies so closely with animals that we’ve embedded animal attributes into our slang (eagle-eyed, stubborn as a mule, lionhearted, strong as a bull, etc.). All children play at being other animals. We often wallpaper nurseries in animal motifs. We use animals as avatars online, and we become part animal in horror movies, not to mention soap operas that feature love-sick half-animal vampires. In the past, we attached our muscles to those of animals, who extended our speed and strength in battle, or carried our supplies. They became a kind of equipment that men often grew fond of, and yet had to watch die in battle, or leave behind at war’s end. As we’ve been learning more about the minds and senses of animals, discovering that they experience emotions similar to our own, we’re developing much more compassion for them.

One moment in the middle of Steven Spielberg’s lyrical epic film version of this story still haunts me. As we are charging through the woods during World War I, amid gunfire, shrieks, and bloodletting, with young men and horses shell-shocked and crazed by horror, the action recedes for a needed break from battle, the camera pauses, and we view the war in a surprising and intimate mirror—reflected on the curved eyeball of Joey, the equine hero. Trauma, like some hallucinogens, lingers for a long time in the tissues, and in that shot one can see exactly how it gets there. Because a horse’s eye is curved, the scene is warped, with men and animals and smoke and balls of light and flying clots of earth leaping in all directions. War is traumatic for horses and other animals—like the humans who create it. The beautifully wrought image says it all, and stings the heart like a line of saber-sharp poetry.

We’ve recruited many unlucky other animals to fight our battles, and only recently have we begun to recognize their capacity for horror and suffering, and to commemorate their sacrifices. Between two busy streets, near Hyde Park, in London, I happened upon a startling war memorial surrounded by a lively crowd of people, several horses and mules, a handful of well-behaved dogs and cats, and a flock of racing pigeons. Older gents in military caps, some in bright regalia from wars long past, displayed medals on their chests and red poppies in their lapels. A mounted Household Cavalry soldier, dressed all in black, rode a matching jet-black Irish horse, which he seemed at times to fade into, except for his white belt and the scarlet stripe down his pant leg and the scarlet band around his cap. Other soldiers in desert camouflage, well-dressed women holding lapdogs, countless veterans, animal rights groups—all milled in admiration around the gleaming sixty-foot curve of white limestone symbolizing the arena of war.

Beautifully rendered in bas-relief on the wall, a parade of camels, elephants, monkeys, bears, horses, pigeons, goats, oxen, and other animals bravely march side by side to war. A few yards away, two heavily laden bronze mules, their strength whittled to the bone, struggle up shallow steps under a burden of rifles and battle equipment, heading toward a breach in the wall. The first mule stretches its arrowlike neck toward a garden visible through the pearly white gates of limestone.

On the other side of the wall, a robust bronze stallion is breaking into a gallop, with a bronze setter beside it, both freed of their burdens. The dog’s head is turned to look back toward fallen comrades. Life’s bas-relief gone, on this side of the wall animals are carved in stark silhouettes and hollowed outlines, like a child’s puzzle waiting for the pieces to be slipped in.

The £1 million memorial, paid for entirely with private funds, bears this legend:

A smaller inscription beneath it reads:

I heard several old soldiers paying tribute to the animals they relied on in so many ways during the war. A veteran sang the praises of the supply mules in the Burmese jungle (their vocal cords had been cut lest they bray and endanger the soldiers). “My life was saved by the mules,” he said, his gaze sliding into the past. “The only way we could get the guns up to us was using them.” Some anonymous animal lover had left a wreath on the memorial whose card read: “You have smelt our fear. You have seen our bloodshed. You have heard our cries. Forgive us dear animals that we have asked you to serve in this way in war.”

Nothing prepares you for how cold the bronze mules are to the touch, or the camel’s sand-matted cement coat. In springtime, beds of daffodils are blooming yellow trumpets. Behind the curve, in the afterlife part of the memorial, the horse is much larger than life, its hooves the size of dinner plates. Too tall to mount, it walks on a lawn of grass sprinkled with tiny daisies. The setter is life-size. Neither has been endowed with a human expression. They are simply and amply animal, healthy and untroubled, relieved of war’s horrors.

Designed by David Backhouse, the memorial poetically captures the plight of the millions of animals who have served and died in our wars. Dogs carried reels on their backs and laid telegraph lines, or ripped their paws raw digging through rubble for survivors. Orca whales became cinematographers, patrolling while holding cameras in their mouths. Pigeons delivered messages from the front. Sea lions dived to 650 feet to recover lost equipment. Beluga whales learned to dial their sonar for surveillance in waters too cold for other mammals to dare. War elephants were ridden on campaign through mountains and jungles. Camel cavalries battled in Arabia and North Africa. And glowworms…

Yes, glowworms. In separate chambers of their body, glowworms (also known as lightning bugs) brew luciferin and luciferase, two chemicals that don’t do much until they’re mixed together. Then they become a magic potion that glows so brightly the insects can use it to blink semaphores of love. Their hind ends become literal lighthouses, leading mates to shore. Sometimes “femme fatale” lightning bugs interfere, by mimicking another female’s flash code and stealing her mate. A siren’s come-hither can be mesmerizing, even on the battlefield, and fill the heart of an insect suitor with light or illumine a soldier’s letter from home. Unlike an incandescent bulb, the light blends into the landscape. And so, during the trench warfare of World War I, soldiers of the Somme read their maps and letters by the cold green light of glowworms carried to war as living lamps.

A hundred thousand pigeons flew missions during World War I, and two hundred thousand during World War II, racing a mile a minute to deliver strange cargo—coded notes in capsules taped to their legs. One notable World War I pigeon, Cher Ami, who flew for the U.S. Army Signal Corps (and died of battle wounds in 1919), relayed twelve urgent messages before being shot in the breast and leg. Despite the blood loss, shock, and shattered leg, he delivered his message—an act dubbed “heroic” by the French, who formally awarded him the Croix de Guerre. Trained at Fort Monmouth in New Jersey, and recruited as an avian soldier, Cher Ami could hardly be thought of as “serving his country.” Still, Cher Ami’s one-legged body is on display in the Smithsonian National Museum of American History’s Price of Freedom: Americans at War exhibit.

Stranger by far, at the height of World War II, the Americans prepared Pacific-bound Project X-Ray, also known as the Bat Bomb Project, dreamt up by Lytle S. “Doc” Adams. Bats had always played an important role in U.S. warfare, because bat guano ferments into saltpeter, a key ingredient in gunpowder, and as early as the Revolutionary War soldiers scraped and mined it from caves favored by migrating bats.

Gathering thousands of Mexican free-tailed bats from Bracken Cave, where twenty million mom and baby bats roost between March and October, Adams and his team fitted them with small incendiary bombs, and planned to tuck them into individual canisters, each equipped with a parachute, and drop them over Japan. At a thousand feet the canisters would open and the bats fly free to roost under shingles and eaves, where they would soon explode, setting fire to whole cities dotted with wooden and paper houses. President Roosevelt okayed this oddball plan and spent $2 million on it. Then one day armed test bats accidentally escaped and torched a Texas air base, after which Project X-Ray was ditched.

Also at work during those years, the American behaviorist B. F. Skinner began developing a pigeon-guided missile. In what was known as Project Pigeon, he trained the birds to steer by pecking at a target. The U.S. Navy revived it after the war as Project Orcon (for “organic control”), and only abandoned the scheme in 1953 because electronically guided missiles proved more reliable. It wasn’t declassified for another six years, just in case.

It’s well known that pigeons, dogs, horses, camels, and elephants have been drafted for war since ancient days. Apparently pigs served in battle, too. Pliny the Elder, who lived in ancient Rome, tells of herds of grunting hogs being loosed to scare the elephants of invaders. Lately, though, we’ve extended the idea of animal soldiers into the realm of lunacy.

The Pentagon’s Defense Advanced Research Projects Agency (DARPA)—whose “psyops” (psychological operations) division most people first learned of in the book and film The Men Who Stare at Goats—trained CIA operatives to practice remote killing on animals. But that was only one of the CIA’s bizarre plans for animal combatants. In Operation Acoustic Kitty, the CIA implanted a bugging device inside a cat, with an antenna hidden in the cat’s tail. This five-year-long, $5 million Cold War project was canceled when the cat, released near a Russian compound, was hit by a car and died while trying to cross a street. Cats were also considered as guidance systems for bombs dropped on ships (the tenuous logic being that since cats hate water they’d steer the bombs they were strapped to toward the deck).

Animals have died in the millions helping us fight our wars, and as our soldiers have become increasingly more technological in recent decades, so have our armed service animals. In 2010, the Chinese newspaper People’s Daily accused the Taliban of training monkeys to shoot Kalashnikovs, light machine guns, and fire mortars at NATO forces. Though the Taliban denied the rumor, it leaves disturbing images in the mind, and conjures up the scene in The Wizard of Oz when a battalion of flying monkeys attacks from the skies. Even watching the movie as a kid, I was scared not by the monkeys but by the witch evil enough to train animals as goons to wage our wars.

The CIA has experimented with remote-controlled cyber-insects, inserting microchips into the pupa stage of butterflies, moths, and dragonflies because, as a DARPA proposal explained, “through each metamorphic stage, the insect body goes through a renewal process that can heal wounds and reposition internal organs around foreign objects.” The result: cyborg dragonflies and robomoths, and search-and-rescue cyborg cockroaches. Other plans have included remote-controlled sharks (with electrodes in their brains) designed to sniff out bombs and explosives, bees trained to replace bomb-sniffing dogs, and hamsters stationed at security checkpoints who are trained to press a lever when they smell high levels of adrenaline.

For more than fifty years, the U.S. Navy has trained pods of dolphins to use their elite echolocation skills and low-light vision to spot and clear underwater mines. They’ve served the navy in both Vietnam and the Persian Gulf, by filming, delivering equipment, and capturing enemy divers (by clamping on a leg cuff roped to a buoy). Mine-hunting dolphins learned to identify underwater explosives without detonating them and report back to their handlers, giving yes or no responses to questions. Sometimes they marked the whereabouts of mines by delicately attaching buoy lines to them; other times they disabled the mines by attaching explosives and dashing away. When Iran threatened to mine the Strait of Hormuz in 2012, and block the vital shipping route, NPR asked retired admiral Tim Keating, who commanded the U.S. Fifth Fleet in Bahrain, how he’d handle the situation.

“We’ve got dolphins,” he said matter-of-factly.

Prized as the dolphins may be by their handlers, the navy regards them as another form of personnel, without rank but classified in true military fashion. For instance, “Mk 4 Mod 0” is a dolphin trained to detect a mine near the seabed and then attach an explosive charge to it; “Mk 5 Mod 1” is a sea lion used to retrieve mines during practice maneuvers.

However, in the summer of 2012 the navy made a momentous announcement. It plans to retire its squads of minesweeping dolphins and other sea mammals by 2017, and replace some with robotic drones called “knife fish” (a fish known for emitting an electric field). Unlike sea mammals, knife fish won’t be able to neutralize a mine, only locate, film, and transmit data about it. Other pods of robotic underwater drones will be guided by fiber-optic cables. I’d like to believe that compassionate motives inspired this decision, but I’m sure thrift also played a role. As a military system, robots are cheaper to field than dolphins, who are heavy to transport to battle theaters in water-filled tanks, and require feeding and medical care.

There’s been a lot of public complaint about sending animals to war and research labs, especially big-brained mammals like dolphins, and maybe it hasn’t fallen on entirely muffled ears. In 2013, after years of concerted worldwide lobbying, the U.S. government finally retired nearly all research chimpanzees and listed the species as endangered. This means that the chimpanzees who have weathered countless illnesses on our behalf are finally being released to animal sanctuaries, and no new chimps will have to face such horrors.

Our dominion over animals, ill-treated for eons in our research and wars, is rapidly being replaced by technology, thank heavens. We have pack mule robots designed to supplant horses and trucks in difficult terrain, robot fleas that leap through open windows and spy, and ambidextrous gymnastic robots that can fill in for human soldiers in toxic areas. But no one has figured out yet how to engineer a dog’s superrefined nose. Dogs can smell a man’s scent in a room he has left hours before, and then track the few molecules that seep through the soles of his shoes and land on the ground when he walks, over uneven terrain, even on a stormy night. Thus far a robot can’t match that finesse. So for the time being we still have dog-soldiers, some trained to kill.

If wars must be fought at all, drones at least are heartless. Alas, their targets aren’t.[14]

Paddling in the Gene Pool

For thousands of years, we’ve left a trail of our preferred traits in the planet’s life forms, in food crops and animals, to be sure, but also in our favorite pets. No other animal is as defined by the long history of its codependency with humans as the dog, so much like us in its capacity for affection and savagery. All dogs trace their ancestry to one canine—the wolf—but you’d never know it looking at Chihuahuas, Bedlington terriers, Belgian griffons, cocker spaniels, Great Danes, boxers, Basenjis, Afghan hounds, or corgis. Over the centuries, we’ve bred dogs for all sorts of jobs and sports: long dachshunds to squirm down badger holes, balloon-chested greyhounds and whippets to race, Entlebucher Mountain Dogs to herd sheep. Lapdogs abound in a fantasia of shapes and colors. Or one can choose a companion dog by intelligence, disposition, or possibly endearing neuroses (tail-chasing, for example). Our feats of selective breeding produce trendy, aesthetically pleasing dogs, including many so inbred that they suffer from about 350 known hereditary diseases, including beagles with weak spinal discs, Dobermans given to narcolepsy, basset hounds with blood-clotting woes, flat-faced Pekingese bedeviled by breathing problems, and Scottish terriers eighteen times more likely to develop bladder cancer. We design dogs so small that they tend to dislocate their kneecaps, and dogs so large they have trouble with their hips.

But, however misbegotten the result of retooling our fellow creatures by controlled breeding, it is an experiment we’ve been carrying on for so long that we no longer even recognize the results as “unnatural.” Now that we have the technology to reach a steely hand into the machinery of cells and remodel the genes, even human ones, our powers are more disturbing, raising all kinds of ethical and legal challenges.

In 2012, John Gurdon and Shinya Yamanaka shared the Nobel Prize for the breakthrough discovery of how to persuade adult skin cells to regress into jack-of-all-trades (“pluripotent”) stem cells capable of morphing into any type of cell in the body—heart, brain, liver, pancreas, egg. It’s as if Gurdon and Yamanaka had found a way to reset the body’s clock to early development, enabling it to mint wild-card cells that haven’t chosen their career yet—without using the fetal stem cells that cause so much controversy.

Space may be only one of the final frontiers. The other is surely the universe of human imagination and creative prowess in genetics. “We are as gods and might as well get good at it,” Stewart Brand began his 1968 classic, The Whole Earth Catalog, which helped to inspire the back-to-the-land movement. His 2009 book, Whole Earth Discipline, begins more worriedly: “We are as gods and have to get good at it.”

Among the rarest of the rare, only several northern white rhinoceroses still exist in all the world. But, thanks to Gurdon and Yamanaka, geneticists can take DNA from the skin of a recently dead animal—say, a northern white rhino from forty years ago—turn it into “induced pluripotent stem cells” (IPS), add a dose of certain human genes, and conjure up white rhino sperm. Then, using in vitro, they hope to fertilize eggs from a living female white rhino, producing offspring to add genetic diversity and rescue the species. Thus far, they’ve successfully created embryos.

With vase-shaped dark faces haloed in soft silver fur, as if even their foreheads were bearded or their auras were permanently visible, silver-maned drill monkeys are the most endangered African primates, swinging through tiny swatches of jungle in West Africa. The few survivors are riddled with diabetes. As a joint project, the San Diego Zoo and the scientists at the Scripps Research Institute are hoping to find a cure for the disease and also enrich the drills’ gene pool: they recently created IPS from the silver-maned drills and coaxed the stem cells to become brain cells.

The same brew of magicians at Scripps is hatching IPS therapies for humans, with the first long-awaited human clinical trials for Parkinson’s disease starting soon. That’s a far cry from dinosaurs grazing in Central Park. Not that dinosaurs are on the table; they’ve been extinct so long that their DNA is no longer viable. But lots of other animals, from passenger pigeons to great auks, are contenders. Curiosity is a natural torrent in humans, one it’s hard as a mudslide to resist. Hosts of people meet avidly at conferences and in research centers to discuss who, how, when, and why to de-extinct. Russia’s Pleistocene Park, where look-alikes of ancient cattle and horses already roam, awaits a shaggy herd of woolly mammoths, even if the grassy steppes they once grazed no longer exist. For some, de-extinction is a moral quest dusted in eco-guilt; for others, it’s a burning scientific challenge. A candid few openly admit that, for them, it’s just too cool an idea to pass up.

At Harvard, the molecular geneticist George Church has pioneered ways to ramble through orchards of DNA, cherry-picking individual genes to produce desired traits or remove harrowing ones. I’ve always found Tasmanian devils endearing, maybe because they’re raucously bad-tempered and quarrelsome to a laughable extreme, and stand up like hairy sumo wrestlers when they fight. Their wild population has been ravaged by contagious facial tumors, and about 80 percent of them have died. Church could pinpoint the gene that’s causing the tumors and erase it from the bloodline. He could recreate extinct passenger pigeons by cobbling together bits of their DNA, if he wished, writing a formula using DNA’s four bases: A, T, G, and C. Despite the futuristic science and lab settings, the vocabulary he and his cohorts use is mechanical and pure Industrial Age. To build a cell, a bioengineer consults a registry of parts, chooses the bio-bricks he wants, and goes through an assembly process: loading bricks of DNA onto a chassis (the E. coli bacterium, for example) in a foundry.

It’s astonishing that we’ve come far enough as a species to think, We’ve driven all these animals extinct… how can we restore them? We have a sense of deep nostalgia about the animals that surround us, and the possibility of de-extincting them. We used to think we had simple dominion over the animals. Today, as we watch plant and animal gene pools dwindling, and pluripotent stem-cell technology zooming, we know that our role is far more complex and that ingenious mistakes require even more ingenious responses.

AS THE EAST Midlands train glides from London toward Nottingham, we pass a show-stopping array of giant old horse chestnut trees with domed crowns and wide shady skirts. Covered in cone-shaped blossoms that sway like incense, they scent the air with a heavenly smell that’s fierce as lilac but more animal. Not barnyard horsey exactly, but leather-sweet and slightly sweaty. Soon the suburbs give way to brilliant yellow stripes: fields of flowering rapeseed whose oil once lubricated our heavy machinery and now enters our trucks as biodiesel and our gullets as canola oil. Around a bend, tall termite mounds sprout in the distance, but as we draw closer they become smoke-gushing volcanoes, and then finally loom as the seven cement chimneys of a coal power station. Clustered together, they’re a monument to the Industrial Age, and the tallest landmark (some say eyesore) for many miles. For two hours, we’ve been escorted by an endless tribe of metal stick men, each with three arms from which steel pinecones dangle, who stride across the land holding up wide skeins of power lines.

All this sparsely settled farmland is what we call the “countryside,” and it fills the eye with bucolic English grandeur, even though some of it is far from native (Canada geese), some has been genetically engineered (canola rapeseed), and much has been machined from lyrical spurts of steel. Even the horse chestnut trees, so synonymous with England, have Balkan ancestry and an industrial secret. During World Wars I and II, British children collected their seeds—the deliciously smooth conkers that we carry in our pockets and serenely rub, polishing them with body oil until they look like mahogany knobs—and donated them to the war effort, where they helped to brew cordite for explosives.

No clouds of starlings pepper the sky before turning on a knife-edge and circling round. The overuse of pesticides has silenced the wildlife they feed on, and now great flocks and swarms and slithers of animals have vanished. Ironically, as a result of crops blanketing 70 percent of the United Kingdom’s land, more biodiversity has begun haunting the cities. Friends tell me London is askitter with red foxes.

I’m struck by the uniform, yielding, furrowed richness of the miles. Single crops parade past the window, along with clans of cattle and sheep. The same monotony of genes rules much of the planet, as wild and varied habitats give way to more prosperous if homogenous big farms. In the United States alone, twenty thousand square miles of land are covered by corn—an area twice the size of Massachusetts. We’re dabbling in eugenics all the time, breeding ideal crops to replace less aesthetic or nutritious or more perishable varieties, leveling forests to graze cattle or erect shopping malls and condos, planting groves of a few familiar trees homeowners and industries prefer. In the process, there’s the gradual eradication of genes, without fanfare, sometimes even driven by good motives.

We’re at a dangerous age in our evolution as a species: clever, headstrong, impulsive, and far better at tampering with nature than understanding it. Who knows what vanishing life forms—and their DNA—we may one day regret losing? Pollen from this sameness of crops will show up in the fossil record as a curiosity of our age; examining it, Olivine will wonder why we wiped out a beneficial smorgasbord of plants in favor of a few genetically modified, fruitless varieties. Will she guess that most of these were bred in the fields of avarice (forcing farmers to keep buying a company’s seeds)?

We’re in the midst of the planet’s sixth great extinction, losing between seventeen thousand and one hundred thousand species a year. It’s hypothesized that what caused the first great extinction, 440 million years ago, was radiation from the collapse of a massive supernova. During the second extinction, 245 million years ago, a possible meteor strike combined with volcanic eruptions killed off so many ocean species that coral reefs vanished for 10 million years. About 210 million years ago, some catastrophic event wiped out more than half of all life forms. The extinction that ravaged the planet 65 million years ago polished off the dinosaurs, sent temperatures soaring by nearly 60°F, and pushed sea levels up more than nine hundred feet. Today’s extinction event, the first during our reign, could end up being the most catastrophic of all. Many scientists predict that, at the pace we’re going, about half of all the world’s plants and animals will vanish by 2100. But, for a change, we know the exact causes of the extinction, having created them ourselves—climate change, habitat loss, pollution, invasive species, big agriculture, acidifying the oceans, urbanization, a growing population demanding more natural resources—and we’re in a position to stop them, if we set our collective mind to it.

So, as species dematerialize around us, worldwide efforts are under way to collect and protect the DNA of as many as possible before it’s too late. Two brave doomsday efforts have been leading the way. One is the Svalbard Global Seed Vault, a remote and heavily guarded underground cavern tucked four hundred feet inside a sandstone mountain on the Norwegian island of Spitsbergen, in the secluded Svalbard archipelago, which lies about eight hundred miles from the North Pole—a James Bond destination safe from both man-made and natural disasters, even melting ice caps (it’s 430 feet above sea level), tectonic activity, or nuclear war.

In some climate scenarios, due to crop shrivel and shortage of fresh water, food becomes scarce. The vault’s mission is to preserve seed diversity, because one never knows what calamity might descend, which crops might fail, and what seeds—whether heirloom or genetically engineered—might offer a solution in the Anthropocene world. The key may be a relic from a bygone era. As Paula Bramel, assistant executive director of the seed vault, explains: “The environment is changing to the point where farmers can no longer maintain the seeds of the varieties that they always used. And that’s really a loss to everybody because that variety may have a trait that’s really critical in the future.”

If those seeds aren’t cached now, they won’t sprout later. Bramel points out this is a particular problem in Africa. We’ve abandoned many heirloom crops because they’re not as cheap to grow in our technological Valhalla, or as blemish-free as we demand. Some are no longer as hardy in our changing climes. We may one day wish we still had them. The vault is the Norwegian government’s farsighted gift to the world; there’s no charge to countries for storing, cataloging, and overseeing millions of backup seeds, which, for the most part, sleep at -0.4°F, in refrigeration naturally provided by the permafrost. Every decade or so, some of the Sleeping Beauty seeds must be awakened and allowed to bloom so that fresh seeds can be collected. Of course, in the best possible future, if such a state of grace exists, they won’t be needed. In the meantime, as a fail-safe treasury, the vault houses millions of specimens of over four thousand different species.

The second doomsday effort lives on the campus of Nottingham University, in the Frozen Ark, which stores the DNA of 48,000 individuals from 5,438 different animal species. It’s Noah’s Ark moored in Robin Hood’s backyard, and its logo is a blue sketch of an ark sailing on a double helix of ocean waves.

For Love of a Snail

Bryan loved snails, though not all snails equally. He was especially fascinated by one turban-shaped gastropod in the genus Partula. Among partulas, he had a thing for the species Partula mooreana. Just like Darwin’s finches, drifting colonies of partulas on tiny islands became cut off from their neighbors and rapidly diversified to a surprising degree in color, size, and shell motifs. Free of natural predators—except the Polynesians who strung ceremonial necklaces from their shells—the snails hoovered up algae on the undersides of caladium, plantain, dracaenas, turmeric, and other leaves in the understory of heavily forested volcanic slopes.

In Bryan’s pale-blue office, I’d seen an old book on his desk, opened to favorite pages of colorful plates. Some of the shells were straw yellow and girdled by two or three narrow reddish-chestnut bands, others light-brown-capped with darker whorls, or cream and purple. Despite their different patterns and hues, they were all partulas. Beside it, several snail-shell necklaces lay in casual loops of pink, brown, tan, and gray. Each tiny shell had been carefully matched for colors and size, and what makes this remarkable is that, according to Bryan, even in one valley shell patterns can vary about every twenty yards. It was disturbing to see the remnants of so many tiny lives ghosting across his desk, their sticky inhabitants long extinct. Their spiraling interiors belong in a church designed by Gaudí; their eye-catching shells remain to delight and haunt us. But their empty beauty tugs at the mind.

Once, a hundred or so species of partulas inhabited French Polynesia, where the shells of the most attractive species, brown-and-green-striped, were prized. They bore such incantatory names as Partula dolorosa, Partula mirabilis, Partula solitaria, and Partula diaphana. In the 1880s an enterprising French customs officer, who enjoyed the taste of snails, decided to start a snail farm and flog snails to islanders. The snails he chose to breed were the plump, succulent giant African snail Achatina fulica. When his snails didn’t catch on as cuisine, he tossed them into the wild, where they began raiding the local crops and gardens and hitching rides to other islands. Faced with heavy crop damage, U.S. authorities on Guam introduced a particularly voracious predator, the carnivorous Florida rosy wolfsnail, Euglandina rosea, into one orange plantation in 1977. But even snails can be picky eaters, and unfortunately the rosy wolfsnail didn’t find giant African snails tasty. Instead it dashed into the adjoining forests, where it hunted down and feasted on the partulas, which for some reason it fancied. Online one can watch ghoulish footage of the carnivores at work, plunging into the shells of small, helpless partulas and gulping them down in mouthfuls with cannibalistic gusto. Ten years later, these rosy wolfsnails commanded the whole island and had devoured fifty species of partulas. Yet another tragic tale of invasive species (and human intervention) gone awry.[15]

Volcanic archipelagos offer natural laboratories for studying how species evolve and reinvent themselves, and so, in the 1990s, Bryan Clarke, his wife, Ann, and their lab assistant, Chris Wade, traveled to French Polynesia to study the partulas. As it happens, I was there at almost exactly the same time; though I was not in pursuit of snails, I know the tapestry of sensations they would have worked among: The spicy sweet smell of scorched sandalwood wafting through the air. Six-man outriggers pulling swiftly past, each with a piece of tusk-shaped wood tied to one side for balance. Dogs sleeping under overturned outriggers in a budget of shade. The sky everywhere full of seabirds, and on land pairs of fairy terns perching like small white angels among the tree limbs while balancing their single egg on a branch. Men heavily tattooed, women swaying as they sang traditional songs filled with baying and keening. Small houses lining the village roads. Here and there, in the foothills, house lights sparkling from the foliage, and beyond them, raincloud-wrapped mountains steaming like volcanoes. Elaborate designs everywhere one looked—on church stones, wooden carvings, and bark cloth—curving like vines and whorling like snail shells, worlds within worlds. It was as if the native artisans had looked through microscopes into the heart of cells.

As a tantrum of sun flashed across the cobalt-blue sea, they boarded a long red-and-white ferry, lashed to the dock by four thick ropes like a wild animal that might otherwise escape, and traveled among small islands with hillsides of bottle green and slate cliffs plunging straight into the sea. It was in this remote spell of thick foliage, light-years from the clipped lawns of England, that they desperately searched for the tiny, rare, beautifully ribboned tree snails.

They found a handful of live partulas on the island of Moorea, but Bryan had a hunch that the ancestor of all 126 partula species might live on the lone island of ’Eua, about two and a half hours from Tonga. Thirty or forty million years older than the other islands, ’Eua isn’t volcanic but a flat chunk of Gondwanaland shelf that broke off and plunked itself next to Tonga. Would they find there the ur-snails that populated all of the Pacific islands?

When they arrived, they discovered to their dismay that the ’Eua islanders had chopped down all of the rainforest in order to plant farms of manioc. Partula’s habitat was gone. Only one faint possibility remained. At the very bottom of ’Eua’s steep ravines, a thin line of trees nestled beside streams. Islanders didn’t risk the climb, and neither did Bryan, but Ann and Chris had come too far to turn back. Pressing on, they slogged down the gorges into the island’s deep green pockets. After three weeks of scouring the plateau, beaches, and the last shreds of rainforest on the island, all they found was one midden of empty shells in a stream at the bottom of a crevasse. Picking up the small, round shells, and turning them gently like ancient coins, they realized that they were about twenty years too late, since snail shells last only twenty years in the wild. Grief-stricken, they held the remains of an extinction in their hands.

According to Ann, the combined loss felt too heavy to bear. Carefully packing a few of the live Partula mooreana they’d found into lunch boxes, they journeyed home to Nottingham. Most of these snails they shared with the London Zoo, which set up a captive breeding program, and Bryan and Ann began breeding the rest, aided by a technician who was a genius at caring for partulas and getting them to have babies. Unusually, even for snails, partulas don’t lay eggs, but have live babies, complete with shells on.

“Here’s a partula with young,” Ann says, opening a book to the startling image of a snail with a perfectly formed second snail emerging from behind its head (where the reproductive organs hide). “These get born just like that.”

“With a soft shell, surely.”

“No, with a hard shell. They’re born as complete adult snails.”

Curiouser and curiouser, I think. The tiny necklace-worthy striped snails that haunted the trees in the kingdom of Tonga sprang from the sides of both hermaphroditic parents fully formed with (surely this birthing might hurt?) hard calcium shells. Not to mention, during courtship they stab each other in the head with calcium “love darts” pulled from their quiver.

Aghast at the pace of Partula’s extinction, a handful of zoos worldwide also began breeding the snails with some success, from a fenced-in partula preserve on Tahiti to the Snail Room at the London Zoo, where one can see them, small as a fingernail, slow-motion slime-skiing along the glass with their nether parts exposed. But there’s no use releasing them back into the wild while hungry packs of rosy wolfsnails still rampage.

“When we came back with the partulas in lunch boxes we were very despondent,” Ann says wistfully, “and I think it was at that very moment Bryan and I thought of the Frozen Ark. Because we’d seen all these partulas dying out. We thought, well, we’re doing this for the snails, who else is doing it for other endangered species? We started to hunt about and we really couldn’t find anyone.”

The Clarkes set up the Frozen Ark Project in 1996 as a response to this crisis, with a single simple objective—to save samples of frozen cells containing DNA from endangered animals before they go extinct. Not as an alternative to preserving animals in their natural environments or to keeping them in zoos, she stresses, but as crucially important extra insurance.

Today a consortium of twenty-two of the world’s finest zoos, aquariums, museums, and research institutions have climbed aboard the Ark and are providing DNA. Only a tiny dab is needed, gathered painlessly from mouth swabs, feces, hair, feathers, or blood during routine veterinary visits. The samples are sent to Nottingham, where they’re cataloged and safely frozen, with backups stored at the home zoos. It’s convenient that DNA is thousands of times smaller than a gnat’s whisker; many individuals exist only as wispy smears on small white filter papers. A single-car garage could store a million; a briefcase could hide enough to repopulate a continent. At the Frozen Ark, specimens hover in liquid nitrogen at -196°F, ensuring viable DNA for hundreds of thousands of years, and hundreds of years for complete cells. Nothing moves at -196°F, but in time these cells could be resurrected and recultured.

Using Gurdon and Yamanaka’s pluripotent stem-cell work, the Clarkes discovered how the Ark’s frozen cargo could repopulate extinct or nearly extinct herds.

“It means we can make any tissue, including eggs and sperm,” Bryan says. “Now, the importance of that is extraordinary, because you could, in principle anyway, reconstruct an entire organism, even when it’s gone. The Japanese, among others, are trying to implant a woolly mammoth embryo into an elephant which would then give birth to it. There are a lot of mammoths frozen in the permafrost.… Of course not for long, because it’s melting.”

Even after ten thousand years of icy slumber, these mammoths are still a treasure trove of frozen DNA, and Bryan assures me that they’d survive freezing for even longer periods of time, and still be viable, if the right method was used.

“I’m very keen at the moment on the idea of freeze-drying cells, you know, like your coffee.”

I try not to picture a jar of freeze-dried woolly mammoth crystals on a shelf beside a jar of dodo crystals, rather like in a country store, but it’s no use.

“The habitat up there in Siberia might be just fine.” Bryan settles back deeper into his chair. “The question then is: What do you do with the mammoth when you’ve got it?! That’s a sort of quandary. Is it better to have two mammoths so they can reproduce and restore the species? I think that would be fun,” he says, clearly charmed by the idea, “and I think they would find habitats they can live in.”

It’s delightful to imagine twenty-first-century woollies, born from elephant mothers (rather surprised at their shaggy offspring?), thunder-stomping through Siberia, maybe sounding an alarm when startled by a de-extincted saber-toothed tiger.

Yet, as we know, mothers teach their babies all kinds of things; our newborn woollies wouldn’t have a mammoth culture. Perhaps they’d imprint on their new mothers like baby ducks and adopt the elephant’s ear-flapping semaphore and yen for dust-baths. Or would they be raised like endangered baby sandhill cranes, who are fed and taught crane behaviors by white-costumed humans flying ultralights? So they’d be woolly mammoths, but not exactly. These mammoths would probably also not have the ancient ancestral suite of woolly mammoth bacterial DNA in their gut and on their skin—the tumbling parasites and symbiotic companions that help make us whole, although Ann tells me it might be possible to revive mammoth bacterial DNA, since, if the tissue is frozen, there’s a good chance the tiny piggybacked frozen smidges of bacteria that went with it would be there, too.

So woolly mammoths and golden toads and baiji dolphins and North American camels might all haunt the Earth again. Or perhaps less controversially, the cells might be used to insert more genetic variety into dwindling populations of almost-extinct animals. Saving animals on the brink by diversifying their genome doesn’t bother most people; it’s a far cry from reincarnating dead ones.

I’m intrigued by the idea of resurrecting Neanderthals, having learned recently that we Homo sapiens harbor between 1 and 3 percent Neanderthal DNA, and when I ask Ann her thoughts on the matter, she’s clearly fascinated by the mystery.

“I hope I’m a very large amount of Neanderthal!” she says, eyes sparkling. “I mean, how fascinating is it? And it appears to be all in the white Anglo-Saxon gene pool! Maybe we’re the thick ones. I worry a bit about those guys. Did we polish them all off—or did they die in the cold, or something? I mean if we polished them all off—that’s terrible.”

Her enthusiasm is refreshing, and I must say, she’s the first person I’ve met who longs to be part Neanderthal, though one of her countrymen, William Golding, wrote a poignantly picturesque novel, The Inheritors, narrated from the perspective of the last Neanderthal as his species was being exterminated by our quick, sly, talkative Homo sapiens progenitors.

“And in the case of some wonderful extinct animal…”

“Saber-toothed tiger?” she offers with clear relish.

“Yes! But would there still be a habitat for saber-toothed tigers?”

“Well, that’s debatable. But I personally think biodiversity is good—and if we could bring back some species that we have made extinct, I think I’d rather see them gamboling about in the fields of Kent, or in a woods, than not at all.”

Although that’s as far as she’ll go, Ann realizes that it’s something the Ark will need to think about. They could resurrect the woolly mammoth or saber-toothed tiger or dodo or anything else that’s extinct. But they’ve decided, for the moment, to stop when they collect the genetic material. With the DNA of two million to seven million species still to back up, their project is far from finished.

“But it won’t stop there,” she says with a sibylline smile.

As we well know (think of the cannibal snails on Moorea), introducing new species can have unexpected consequences. And, yes, de-extinction is a divisive topic, even among the diverse members of the Frozen Ark’s own consortium. A chief concern from naysayers is that it would divert attention from the serious work of conservation—protecting animals and ecosystems from going extinct in the first place. Critics also worry about the DNA of extinct species weaving through wild populations as ancient newcomers, a different kind of invasive species, one from the past. Both concerns are undoubtedly valid. I’m also troubled by how de-extinction plays into an increasingly mercantile view of life in which most anything is disposable and replaceable by a newer synthetic model. On the other hand, like Ann, I’d really love to see a formerly extinct zebralike creature “gamboling in the fields of Kent.”

Collecting DNA is one thing; agreeing on what to do with it is another. From the Frozen Ark’s point of view, there is enough work saving the DNA. Future generations can decide what to do with it in light of the new technologies that emerge. What began as an effort to bank the DNA of only the most endangered animals has now evolved into an urgent banking of whole ecosystems. The Ark goes into an area and collects everything that crawls, flies, scampers, or slithers. In a tropical rainforest with its thick canopy, groups of people spread sheets underneath a tree, and they shake it. As I picture raining insects, frogs, snails, and moths, I feel sure Ann finds the shaking and collecting great fun. I know I would. We haven’t named more than about 65 percent of the biomass of all the species on Earth. So, yes, shake it down, and freeze it, and take it to the Natural History Museum, and label it—so we can tell whether it’s an ant or bee or moth—and let the taxonomists name it officially later.

Nottingham stores the DNA of the courtship-crooning Mississippi alligator, giant squid with dinner-plate-sized eye, secretive snow leopard, blue-throated macaw from the Bolivian rainforest, iconic African lion, and square-lipped northern white rhino, among many others. My mind’s eye automatically pictures each species in turn. Only about 20 percent of the species are on the endangered species list, and some are not endangered at all. Ideally, the Frozen Ark would store DNA from every species on Earth, but that’s not practical. The mammals would be easy, but the bugs would take a long while, especially the beetles, since there are more beetles than anything else on planet Earth (one of my favorites being the dung beetles who navigate by the stars like ancient mariners).

As I set down my cell phone, Ann notices my screen saver of an insanely cute baby wombat, a face that could melt a thousand hearts, and her eyes widen in appreciation. She’s just returned from a meeting in Sydney, so I ask her how the cancer-plagued Tasmanian devils are doing.

“They can cure the cancer in captivity,” Ann replies, her face showing her concern, “but it’s the ones in the wild that are the worry.” With a grim nod, she continues, “And the koalas have got chlamydia. And I heard some of the wombats are getting sick.”

Just over a hundred of the northern hairy-nosed wombats, the world’s cuddliest marsupial, survive in a tiny plot of Queensland. Though once numerous all across Australia, they feed on grasses, and when humans arrived with agriculture and herds of cattle (essentially four-legged mowers), the wombats simply couldn’t compete. Drought and invasive species have been polishing off the wombat’s supply of native spear, tussock, and poa grasses. It’s hard to picture Australia minus most of its famous creatures. Conservationists are trying to treat them in the wild, but Ann doesn’t think that Australia’s terribly worried about the extinction of its animals.

“They’ve got this beautiful country and everything looks perfect, and there’s not huge numbers of people crashing about,” she says.

“So they think it’s forever.”

“They think it’s forever,” Ann repeats with incredulous fervor. “But I think Americans are more interested in conservation. Don’t you think so?”

In my experience, I tell her, Americans are deeply concerned about conservation, but we have clashing, fiercely defended opinions about how to do it. Some believe it’s essential to preserve our majestic national parks; some, that the parks are a lost crusade and that safeguarding animals in big preserves just hasn’t worked. Some believe in rewilding’s networks of “cores, corridors, and carnivores” to reconnect and rebalance unstable ecosystems; or Pleistocene rewilding—in North America, unloosing elephants, lions, bison, and cheetahs (the closest living relatives of the ancient native megafauna) to roam the Great Plains. Others argue that all of the above are last-epoch thinking, and, as an increasingly metropolitan species, we should weave more of the wild into the cities where we live. Ann feels certain that we need multifaceted solutions.

“You’ve got to try the wild, but obviously that’s all going to go west if one’s being realistic.”

For a moment, I think perhaps she means the expanse of America’s West, then quickly realize she means die, as in following the setting sun.

Ann says firmly, “You’ve got to have parks. And you’ve got to manage your wild.”

“Managed wilderness. You don’t think we can afford to just let nature run wild anymore?”

“No,” she says with conviction. “We really can’t.”

Nature has become too fragmented to just run wild.

Ann tells me of a local solution that works: how in English towns, where terraced housing is commonplace, small back-to-back walled gardens lead onto each other and combine to create long fertile corridors for wildlife.

“So when I go into Cambridge and do a bit of gardening,” she says, “I’m surrounded by all sorts of insects and mosses and butterflies. But in our country home’s garden, there’s nothing. Consider starlings. They put their beaks down about four centimeters into the soil—that’s how they feed—and that’s where all the pesticides are accumulating in the agricultural areas. The environment would be absolutely fine for them if there just weren’t any pesticides in it!”

Hoping to lure pollinators back, what’s known as Plan Bee rewards landowners for planting wildflower meadows for knapweed, bird’s-foot trefoil, red clover, and other weeds favored by insects, butterflies, and bees. They’re called “bee roads,” perhaps in keeping with the Anglo-Saxon tradition of referring to the ocean as the “whale road.” Other English bees have become prosperous city-dwellers, unassailed by agricultural pesticides, and there are now more sparrows, starlings, and blackbirds in the town gardens than in the open countryside.

A sorry image of the English countryside, silent at dawn and devoid of wings, slinks through my mind. All the more reason I like Ann’s “try everything” mindset. Yes to national parks, to rewilding preserves, to wildlife corridors, to city shades of green, to DNA banking, and to any other strategy we can think of that will allow animals to pursue their dusty, feral ways and nature to stay replete with potent life forms.

The office door swings gently open, and Chris Wade pokes his head in to take me on a tour of the lab. A tall man with dark curly hair, Chris does DNA analysis on the samples that arrive by mail, and he’s looking forward to being part of the Ark’s upcoming expedition to Vietnam to collect fresh DNA samples. Walking across the outer office, we enter a shared college lab with pale-blue walls, workbenches, microscopes, and a bevy of white lab coats hanging on one wall like a colony of albino bats.

Chris explains that they take the DNA field samples in several forms to be sure of backups. Dropping a tissue slice into a tube and topping it up with ethanol essentially pickles the tissue. That state of DNA isn’t ideal; it’s not as high-quality as fresh-frozen DNA. But if they put a specimen in a freezer, and the freezer were to break—and in a lot of countries that’s often a problem—then it would be completely destroyed.

You’d think freezing would kill the cells, but the arkmasters control the rate of cooling, at only a degree a minute, and that slow-motion plunge keeps the cells intact. For safety, they prefer a three-way approach:

“One: Ethanol. Tough as nails,” Chris says, “but there for you in the end—the freezer can go off, everything can go wrong, you will still have that preserved bit. Two: We’ve also got our fresh-frozen tissue slice, which is perfect, it’s got everything. Three: And then we’ve got another sample for later cell culture. That’s the ideal scenario, all three methods.”

He leads me to the far end of the lab, through a doorway painted cornflower blue, into a small room, where four tall white Sanyo freezers stand, looking surprisingly humdrum, suitable perhaps for a wintering farm family, not the biggest snow survival fort the world has ever known. I put on green latex gloves to protect my primate skin.

He tugs opens a freezer door that gusts a small white cloud, like the combined souls of ten thousand animals exhaling in unison on an ice floe. Inside the freezer sit row after row of frost-covered drawers. Pulling one open with a gloved hand, I’m surprised to find only carefully arranged rows of short frost-covered vials, each with a label.

“You can lift one out,” Chris says in a tone of voice warning But carefully!

When I do, I see that I’m holding the future of an African lion. If I blink, a tawny-colored male lion with a shaggy mane is standing on the veldt of my palm. I blink again and the whole animal is nestled in my hand, with room to spare for tall grass, heat mirage, and his pride. What an unlikely way to safeguard the future of animal-kind.