The Human Age: The World Shaped by Us Read online

  Meanwhile, TU Delft is working on other forms of airborne windpower, including a “ladder mill,” which is really a string of kites whose blades ride the high winds aloft. “If we move away from the idea that a turbine ought to have a steel foot,” Djairam says, “we can harvest this wind for our electricity supply.”

  When it comes to reaping energy from the eye-scalding powerhouse of the sun, we’ve only begun to explore its promise of beneficent fury. Over the millennia, humankind has worshipped the sun, and with good reason, but these days we rarely pause to marvel at how it charms our existence. It reaches into the mumbling corners of our private universe, spurs growth, sheds light on all our episodes and exploits, transfigures daily life. Its edible rays feed the green plants on land and sea, which animals graze upon, and we dine upon in turn, and so it quivers through our blood. Every molecule of our being, every mote inside us, every atom and eave in the mansion of the body and the penumbra of the mind was forged in some early chaos of a sun. It’s only in death that our long conversation with the sun ends. Other elements in our world may trace their origin to lesser luminaries—the gold we mine, for instance, to a sparkling bombardment of asteroids two hundred million years ago. But the sun’s breath made all of life possible.

  You’d think that would be enough for one species of upright ape, but we rack our sun-smelted brains to find newer ways to capture and enslave the sun to power the rest of our lives. We’ve been exploiting it throughout the Anthropocene whenever we’ve burned fuel—really a form of buried sunlight—to warm ourselves and power our empires. The Industrial Revolution always was about solar power. Now we’re just skipping the secondhand part and going straight to the wellspring of that fuel. Wood, coal, oil, and gas were only intermediaries after all, and using them was a sign of our immaturity as a species.

  Sweden’s Ripasso Energy is not the only endeavor beginning to excel at solar power, even if it’s not yet as profitable as fossil fuels. It will be, because it must be, and soon, if we’re to survive all of our masterpieces and conquests. In Nevada, Ivanpah, the world’s largest solar thermal facility, already stretches to the horizon in the Mojave Desert. And it should. America receives as much sunshine as light-spangled Spain, the sunniest country in Europe and the world’s leader in concentrated solar power. In the coming years, Desertec, a far-reaching $400 billion project, plans to harvest solar energy from Africa’s sun-drenched deserts and pipe it to the world. Ample sunlight falls on North Africa each day to power the whole continent, as well as Europe, and Desertec’s ultimate goal is to collect enough sunshine in deserts to power the entire planet.

  In Germany, solar panels line rooftops like glossy guitar picks, sparkle with pent-up power beside the railways, spangle like beaded frocks on the hillsides, escort cars along the autobahns, stand on stalks and peer up at the sky like sunflowers. They’re everywhere one looks, pulsing from inner-city apartments to barns and old abandoned military bases. In the Gut Erlasee Solar Park, where straggling weeds climb between the panels, threatening to shade them, a maintenance crew of grazing sheep dutifully prunes the intruders. In the southern German state of Bavaria, home to 12.5 million people, three solar panels take up residence for every human. While Germany doesn’t get an enormous amount of direct sunlight, on one prismatically sunny day in May 2012, it harnessed 22 gigawatts of energy from the sun—as much bottled lightning as twenty nuclear power plants could create, half of all the solar energy being collected around the world that day.

  Thanks to shrewd legislation passed in 1991, including financial incentives and widespread support from a citizenry well tutored in the need for renewables, Germany has become a world leader, harvesting wind, water, and sun power for a quarter of its energy needs, with solar providing the lion’s share, and German companies spearheading solar technology research and design. The sun’s rays may be free, but they’re not cheap to use. Solar energy still costs more than fossil fuels or nuclear energy, but prices have fallen 66 percent since 2006, making it obvious that trained sunbeams will soon be as affordable as coal. Meanwhile, solar research is heavily subsidized by the government and also heavily backed by investors. But even without government subsidies, solar energy is flourishing in India and Italy, and China is surfing the solar energy wave with such flair that some German tech companies are being eclipsed by suddenly plummeting prices. Ideally, every home would have solar panels and affordable fully electric cars that could be plugged into the sun, a molten socket that stretches 92,960,000 miles.

  Many communities and countries around the world are finding creative new ways to harvest and reuse energy, but most grassroots initiatives aren’t covered by the media; even though they may be life-changing locally, to the rest of the world they’re invisible. Dayak villagers in Borneo are replacing their diesel generators with hydrogen ones and hydroelectric energy (from streams) to power their lives. In Curitiba, Brazil, once crippled by traffic, 70 percent of commuters now travel by bus, saving twenty-seven million liters of fuel a year and lowering air pollution.

  Climate change has become so visible, and wildlife and fresh water so much scarcer, that fewer people are foolish enough to deny the evidence. As we wade into the Anthropocene, we’re trying to reinsert ourselves back into the planet’s ecosystem and good graces. Unlovely as the word “sustainability” may be, it’s sashaying through the media, taking root in schools, and hitting home in all sorts of domiciles, entering the mainstream in both hamlets and megacities. We’re undergoing a revolution in thinking that isn’t a reaction to the Industrial Revolution, nor is it a back-to-the-land movement of the sort that became popular during the Great Depression and again in the 1970s. We might sometimes resemble startled deer in the headlights as we face Earth’s dwindling resources, yet at the same time we’re opening a door to a full-scale sustainability revolution. Our fundamental ideas about house and city have begun evolving into the smarter, greener matrix of our survival.

  PART III

  IS NATURE

  “NATURAL”

  ANYMORE?

  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.” 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 wi
ngs 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.