Ten years ago, I went into the woods I loved to decide whether or not to leave them. I walked through the wide open door of the barn where I lived, on the green side of Oregon, veered west between the overwintering garden and the greenhouse where the rosemary thrived, and passed through grassy fields that flushed into knee-high carpets of silken violet petals when the camas came into bloom. At the edge of the property, I climbed into the forest, leaving the open meadow behind and bushwhacking steeply uphill into a remnant parcel of old-growth Douglas fir trees.

Somewhere hidden in the upper branches above my head were a pair of spotted owls that lent the land protected status, as long as they stayed. I drifted to the north, winding between granddaddy trees and prehistoric ferns, my boots sinking into the spongy beds of moss underfoot. I dropped down into the steep ravine of a creek, stone-stepped across, scrambled back up the other bank. Traveling where there was no trail, I used the lay of the land as my guide. Looking. Thinking. Deciding. Undeciding. Redeciding. Could I leave this for New York City?

Along the path of a deer trail, hypnotized by green and oxygen and swept up in my tornado of indecision, a cluster of Indian pipes leapt into view, ghostly and translucent. They rose like spectral stalks of asparagus from the leaf litter, feeding off the fungi that linked to the trees around them. They could thrive without light. It felt like an affirmation, and I fell to my knees, the way John Muir did when he spotted a Calypso orchid in a tamarack swamp, awed by the impossibility of its diaphanous beauty. I could leave and keep this wild beauty within me. I could go to New York City and survive. I could cross the border between this place of corporeal earth and wood, and step into New York, a construct of words and ideas. I would be okay.

And it would be temporary, this sojourn to work my brain as hard as, in Oregon, I’d worked my body. I would collect a graduate degree in journalism and stay for seven years, until love lured me to Cape Cod. For those years in the city, I thrived on the diversity of humans, no longer the only brown-skinned one in a bunch. I was thrilled to never know what language might emerge from a person’s mouth when they first opened it to speak. There was the rush of going to see a movie and then heading to the public library on public transportation to listen to the director and actors talk about it. It felt indulgent that my job as a student was to read Joan Didion and graphic novels and write about whatever I wanted. I slept with strangers on rooftops, looking up at one or two stars that permeated the glowing night sky, my blood saturated with Guinness, Irish fiddles looping in my ears. But in those heady urban days, I missed the Pacific Northwest, always. Sometimes I alienated potential friends, slipping into reveries about barns and goats and Indian pipes.

The memory of that pensive trek into the woods came back to me when I returned, recently, to that same pitch of land in Oregon, those same fields and the greenhouse, now cultivated with different crops. The barn was undergoing renovations but the land had remained constant. The scent of dry fields and Douglas firs evoked a comforting familiarity that, in the city, I had experienced only when the sidewalks were crowded with vendors selling Christmas trees trucked in for the holiday season.

In the time I’d been gone, there had been a shift. Of course I had changed, and the trees had grown taller, but a greater swing—the kind that happens on a geological timescale of thousands or millions of years—was beginning to be widely acknowledged. Some scientists were becoming urgently vocal about the need to recognize that, in recent centuries, the world had entered a new epoch. They called it the Anthropocene. Planet Earth was now defined, they said, by the complete and utter dominance of human beings.

It was Paul Crutzen, a Dutch Nobel Prize-winning atmospheric scientist, and Eugene F. Stoermer, a Midwestern phytoplankton expert, who coined the term “Anthropocene” and brought the concept to the mainstream in 2000. They took a notion that had been floating around for nearly a century and turned it into an argument: now, they proposed, was the time to formally recognize that human tinkering impacts every facet of life on Earth. According to Crutzen and Stoermer, along with a growing number of academics in the sciences and humanities, we are radically changing the geo-chemical makeup of the planet at a pace previously caused only by cataclysmic events, like massive asteroids colliding with Earth. After an 11,000-year run, we have left behind the Holocene, the epoch spanning time since the last great ice age. The defining characteristic of our new epoch is us and all the things our creative brains have generated to keep ourselves alive, fed, watered, housed, clothed, bejeweled, stimulated, elevated, educated, entertained, and multiplying.

Discussions and debates about this will continue to bounce around the editorial boards of Science and Nature, and the meetings of the Geological Societies of America and London, until the International Commission on Stratigraphy makes its official declaration, expected as early as next year. The Commission will rely on the findings of a thirty-seven-member working group of earth scientists familiar with deep time stratigraphic history who are currently comparing the rate of environmental change caused by anthropogenic processes with the environmental deviations of the geological past.

Whatever they conclude, ours is undeniably the age of humans. Consider that three-quarters of the Earth’s ice-free land can no longer be considered wild, and that extinction rates are estimated to be a thousand times higher than they would be in a people-free world. We made that happen. Consider the chemical alteration of the atmosphere above, clouded with greenhouse gases, and the deep blue ocean waters acidifying below. We did that, too. Consider the flame retardants collecting in the buoyant blubber of beluga whales singing their songs in the Bering Sea. The swirl of plastics throbbing at the heart of the Pacific Ocean. The fact that most of the nitrogen in our own bodies was manufactured in a factory. All of that is our doing.

We have stepped into the role of alchemists, fundamentally altering the elemental chemistry of the planet.

While the call for a declaration did not come until 2000, Crutzen and Stoermer mark the starting point of the Anthropocene somewhere around the time James Watt revolutionized the steam engine in 1784, tipping the first domino of rapid anthropogenic change on Earth. Human impact was far from negligible before the Industrial Revolution: we did a right proper job of deforesting most of the planet, even with the smallest of axes, and it is possible that we played a pivotal role in mass extinctions (according to the “overkill theory” that hypothesizes that early hunters managed to wipe out the megafauna of North America). But in the past two centuries humans have gone far beyond simply reorganizing the world, cutting here and digging there, moving things from place to place. We have stepped into the role of alchemists, fundamentally altering the elemental chemistry of the planet. The C-14 shadow of atomic bomb detonations from the late 1950s still lingers in our cells, an embedded time stamp even on those of us not born until decades later. Use of the pesticide DDT came and went in Western nations, but the chemical still seeps from the breasts of lactating mothers many years after it was banned. The Anthropocene has staying power.

Sometimes, the flora and fauna of ecosystems that have evolved over the course of millennia have adapted to the sudden changes we’ve wrought. Sometimes they have not. The last Vietnamese rhinoceros died in 2010. Golden toads were declared extinct in 2007. The fossil record of the baiji dolphin reaches back 25 million years but presumably ends around 2002, the last time one such dolphin was sighted in the industrialized waters of the Yangtze River. Eminent biologist Edward O. Wilson proffered an alternate name for this new epoch—the Eremozoic, meaning “the age of loneliness.” (Lonesome George, the last Pinta Island tortoise, died on a Sunday morning in late June, 2012.)

“It’s no longer us against ‘Nature,’” Paul Crutzen wrote in 2011. “Instead, it’s we who decide what nature is and what it will be.”

Back in Oregon, the boundaries between people and nature seemed clear to me. I could delude myself into thinking they were defined by the edges of the old-growth-forest tracts my friends and I fought to protect from logging. That they hung in the divide between my barking dog and the pack of coyotes that yipped as they passed through on their way to wherever. But even then, it was clear if you zoomed out and up and saw the former forests denuded of trees, that land of Cascadia was a patchwork quilt made of remnants.

The Anthropocene was easy to observe in Manhattan. New York was the anthropocity of the Anthropocene, life made by and for humans alone. The brownstones full of history and the looming cranes erecting glass-walled towers. The descent on a seemingly bottomless escalator to watch a movie in the enclosed darkness of the Angelika Film Center on Houston Street, where the floors would rumble when subterranean trains passed close by.

But there were ragged tears in the seams of civility, and if I leaned in close I could glimpse something more magnificent and uncontrollable on the other side. I sought out these moments during my years in the city, hunting for places where I could escape the fingerprints of human activity. I used journalism as an excuse to find those who saw green in the gray cityscape.

I latched onto the biologist who manages New York City’s falcons, the densest urban population of peregrines in the world. Chris Nadareski knew the locations of the city’s sixteen nest sites, and placed plywood boxes lined with stones in the precarious places where the birds tried to raise their young, to increase their chances of success. He visited each nest at just the right time every spring to encircle the young birds’ legs with identification rings. He knew their genealogy. He told me stories about incestuous pairings, about the time a male falcon raised his young chicks alone after his female mate was killed. The peregrines nested where they pleased, on skyscraper balconies or bridge tops. Seeing them made me feel airborne.

The first time I met the biologist with the sun-kissed face and the scratched forearms was at the Riverside Church on the Upper West Side, after he’d accepted my request to observe his work. Chris carried a basket holding a falcon chick fresh from a week in rehab. It had been recovering from a double ear infection that might have killed it. Now it was ready to be returned to the nest. We stepped inside the church, where people were arriving to pay their respects to a longtime member of the congregation who had passed away. A small crowd gathered around us. They gasped as Chris picked up the bird; its high, raspy cry echoed down the hall. A guard cooed, “Oooooo, my baby,” over and over. Cameras appeared out of pockets and purses.

The biologist and I ascended to the twenty-first floor of the church, just under the site where the carillon rang the largest bells in North America, and we squeezed into a dark machine room. Chris left me in charge of the chick as he opened a leaded glass window leading to the ledge where the nest was. Wind blew in from the opening, swirling loose feathers and dust and mingling with the smell of oil and grease as Chris leaned forward, the Hudson River hundreds of feet below and a stone gargoyle jutting out just above his head. The bird’s three siblings—downy creatures the size of softballs, sitting fluffy and awkward on their haunches, yellow leathery feet splayed wide—watched him intently. Their parents were out on the wing somewhere, and would arrive to find their disappeared offspring magically returned.

The bird took a moment to look back at the human who had taken him away and improbably brought him home.

I stared down at my charge at the bottom of the basket. It was just a bird, but a bird that couldn’t be found anywhere on the East Coast forty years earlier, when DDT was so abundant that every falcon nest failed, the eggshells thinned beyond survival. This bird was hope. There in a room far above the famous Riverside Church sanctuary that gives so many people a place to put their faith, I looked into the bird’s dark eyes and found a place for my own.

Chris turned to me and reached into the wicker basket, lifting up the falcon and giving him a final inspection. “Okay, there you go, little guy,” he said softly, placing the recovered male onto the pea gravel of the protected nest. The bird took a moment to look back at the human who had taken him away and improbably brought him home. Then he took a few steps toward his brothers and sister. The falcons sat together in silence, on the edge of a world they would soon discover in flight.

A week later, I joined Chris when he went to band barn owls at the Jamaica Bay Wildlife Refuge. I’d return for multiple springs to help, taking the A train to the subway-accessible refuge that sits adjacent to JFK International Airport. While we labored to protect the wild birds, others at the airport shot gulls to reduce the chance of an avian collision bringing down a commercial flight. (When a US Airways flight crash-landed on the Hudson River in 2009, it was because birds had knocked out its engine upon takeoff from LaGuardia.)

With an orange-eyed osprey in my hands and jets flying overhead I wondered where I belonged. On the hazy horizon to the distant west, I could see the Empire State Building, where I had stood one night on the observation deck with camera-clicking tourists and watched a peregrine hunt for migratory songbirds, successfully, using the upturned lights for illumination. But although I loved the city’s undomesticated pockets, they were as much an illusion as the forty acres of spotted owl habitat next to my barn in Oregon. I could only get so close to the raptors because mine were human hands, indistinguishable from the ones that had nearly obliterated the species in North America.

A few days after revisiting Oregon, I attended the Breakthrough Dialogue, a gathering in the Bay Area of the Breakthrough Institute, to which I’d been invited to interview the keynote speaker. This tribe of self-defined EcoModernists, who released a manifesto earlier this year, see themselves as the demon slayers of the old-school environmentalism born of the Silent Spring era. The save-the-whales approach to protecting the planet, they argue, is not only outdated but utterly failing. The EcoModernists want us to jettison the tactics of the 1970s and get over our guilt about the havoc we’ve wrought. They believe that with human ingenuity, we can solve any jam we’ve gotten ourselves into, from hunger to climate change to energy shortages.

The deceptively straightforward theme of the Breakthrough Dialogue was “The Good Anthropocene.” There, in the shadow of the Golden Gate Bridge, the EcoModernist faithful—alongside the critics they had generously invited and a handful of skeptics, like me, who hovered cautiously in between—attempted to unpack the meaning of both “good” and “Anthropocene.” Attendees included one of the top environmental journalists in the country (who finished his panel with a song), Republican politicians, Economist editors, and fabulously wealthy philanthropists. Conversations were sustained and intense, at sessions, in the halls between them, and around a fire come nightfall.

Though the EcoModernists deny being techno-utopians, the discussions at the conference were dominated by Silicon Valley-style optimism. We can fix global warming, they contend. We can grow animal-free meat in a laboratory and use genetically modified organisms to save modern agriculture and feed the hungry. We can build nuclear power plants to produce all the clean energy we need. We can even rewild central California with wooly mammoths.

(With apologies to the EcoModernists, I’m not sure what could be more techno-utopian than rewilding, the term for reintroducing extinct species. It would involve sequencing the entire genome of the lost species from an ancient relic of bone—then matching it to its closest living relative and fiddling with the genes, one by one, until they most resembled those of the creature, be it passenger pigeon, Steller’s sea cow, or wooly mammoth. Then shooting the tweaked DNA into a cell and coaxing the cell into an embryo and implanting the embryo into that closest living relative and waiting for the miracle of life. From that point, there is only the minor question of where, exactly, to put a baby mammoth.)

The EcoModernists embrace the Anthropocene, but insist they do not believe Homo sapiens are at the center of everything. They love nature, they claim, and seek to create a human society so technologically advanced that there would be no need to raid the wild. In the EcoModernist view, it’s best to ramp up the rural exodus that’s already underway and concentrate ourselves in cities. Our urban efficiency would enable us to leave those places of extraction alone—to, as they write in their manifesto, “liberate the environment from the economy.” In our absence, it would thrive.

When the manifesto authors write, “cities both drive and symbolize the decoupling of humanity from nature,” they are partly right. At my Oregon barn, days would be filled with splitting and stacking the wood that fueled my stove, which cooked most of my food and heated my indoor space, along with the water in my outdoor shower thorough the long wet winters. Wood stoves are smoky and inefficient, horrible carbon emitters, but splitting the wood and stoking the fire kept me connected to the source. When I moved to New York, my illegal sublet didn’t even have a thermostat. I had no control over the temperature that broiled the small space, forcing me to crack open windows in the middle of blizzards. Yet my heat came from somewhere beyond the walls of my urban apartment. So it seems dreamy to believe that people might all move to the cities and no longer rely on any of the stuff “out there”—in the future habitat of the wooly mammoths—to keep us going.

When have humans ever looked at something we need, or even just want, and walked away?

The EcoModernists maintain that it’s wholly possible for humans to stay on one side of a boundary while wild things blossom in peace on the other, rejecting the idea that to avoid economic and ecological collapse, humans need to cooperate with nature. But when have humans ever looked at something we need, or even just want, and walked away? By some accounts, ninety-six elephants are poached every day in Africa, solely for their long, tapered tusks, a luxury coveted but useless.

The self-importance of humans isn’t new. It bloomed, arguably, during the Enlightenment, when we began to figure out how the world works, the aura of mystery tumbling away from lightning strikes and earthquakes to reveal the mechanics underneath. In 1820, the English poet John Keats lamented our audacity when he wrote that science might as well “unweave a rainbow.” In 1968, environmentalist (and EcoModernist) Stewart Brand published the inaugural Whole Earth Catalog, the instruction manual for a new generation of do-it-yourselfers, writing: “We are as gods and might as well get good at it.”

Yet we are not omniscient. Everything we learn today reveals what we didn’t know yesterday. We have indeed solved some of what the EcoModernists call wicked problems: We live longer. Fewer of us perish in childbirth. We know how to ward off epidemics by washing our hands, and how to unleash the power of antibiotics. But we have yet to figure out how to get this basic information to an appalling large segment of the human population—or why we should, when there is no money to be made. And many of these solutions merely resolve problems of our own making.

So while the optimism was feverish at the Breakthrough Dialogue, after two days there I’d gone cold. God was dead in Sausalito. I didn’t mind that part, but what troubled me was how casually we’d usurped the duties we’d once ascribed to the deity. Among the EcoModernists, there was no sense of deep ecology. There was no acknowledgement of the iron law of unintended consequences. There was no humility.

Something gravely important had gone missing. Something related to reverence—to holding on to the ineffable wonder of what already is, caring for what little remains, being cognizant of how quickly we’re losing it. As we attempt to develop new energy sources and figure out how to feed ourselves and inhabit this warming world, we need to remember what, apart from technological worship, drops us to our knees.

In Kenya, years ago, I was sitting in a Jeep by the side of a river when a small herd of elephants appeared and ambled around the vehicle, locking us in position. With no way out, we stayed put and observed the swing of their trunks, the way a young elephant crossed one thick leg over the ankle of the other as he stood at rest. I listened to their resounding breaths and humphs. Eventually they moved on.

There is no trail going forward. We have to follow the lay of the land. We need to remember that when we leave the woods, it is not so easy to find our way back. Once severed, the ties to the land that fed our souls cannot always be repaired. My hope is for a “good” Anthropocene crowded with falcons and Indian pipes. An epoch where humans will find the idea of keeping today’s elephants alive as urgent and beguiling as that of reintroducing wooly mammoths to a world of our own imagining.