On Conservation, De-extinction and the Precarious Future of Wild Things
By M R Connor
When I was a kid in the 1990s, the world often felt like it was on the verge of catastrophe. At my California public school, to offset drought, teachers taught us to conserve water while brushing our teeth. I saw news stories about environmentalcrises such as burning rainforests and acid rain. None of these issues loomed as large in my imagination, though, as the idea that the world is in the midst of a “Sixth Extinction.” In the early 1990s, Richard Leakey, the famous Ken- yan paleoanthropologist, used this term to describe the phenomenon of disappearing species; and it gained wide acceptance in the public domain, giving gravitas and urgency to media reports and conservation campaigns. When I was in middle school, I heard predictions like those made by the British environmentalist Norman Myers, who estimated that 50 percent of all species at that time would go extinct in the twenty-first century. Harvard biologist Edward O. Wilson estimated as many as 27,000 species were going extinct every year. Trying to understand these numbers is bewildering for anyone. As a kid, the idea that every hour three species disappeared was incomprehensible. I didn’t understand how there could be so many species on earth that we could lose so many. But I internalized these statistics, and developed a concern for the fate of species rooted in two beliefs: extinction is bad, and saving species from extinction is good.
Then a few years ago, I found myself in the back of the Bronx Zoo’s Reptile House peering through a little pane of glass into a room full of terrariums. Through the condensation on their walls, I barely made out dozens of blurry, yellow frogs climbing over green moss. I wanted to get a closer look but the room was off-limits: the only people allowed inside were the herpetologists responsible for the frogs’ care, and even they had to disin- fect the bottom of their shoes with bleach. The frogs inside this bio-secure room were incredibly rare, one of two populations left in the world, both in captivity. The waterfall where they had come from in the Tanzanian rain- forest was now the site of a hydroelectric dam, and the species was confined to these terrariums, painstakingly kept hydrated with an artificial misting system and fed specially bred insects. It was like peering into a hospital ward at a patient on life support.
The great lengths that had been taken to save the frogs from extinc- tion intrigued me, and a year later I was in Tanzania interviewing some of the central characters of the Kihansi spray toad story. I expected to learn a lot about conservation biology. Instead I found myself on a crash course in national politics, development economics, racial privilege, bureaucratic subterfuge, and environmental ethics. I realized that my belief that con- servation is self-evidently good was actually a social and cultural bias. By the time I made it into the country’s remote forest where the frogs once thrived, I was having thoughts that would have previously struck me as unenlightened: maybe they should have just let those toads disappear. Staring at their former habitat, a mere two hectares of wetlands, the spe- cies struck me as a kind of evolutionary whimsy, extraordinary for its per- fect adaption to a waterfall and beautiful for its incredible rarity. But now they were confined to a little bathysphere suspended in a world aflood in disaster. Was that better than extinction? I couldn’t say for sure. The mil- lions of dollars that had been spent on their conservation seemed almost cruel in the context of the immense poverty of rural East Africa. Saving species, it turned out, was not a simple thing with bad guys and heroes and tidy endings.
In the years following my reporting in Tanzania, I began looking at other cases of threatened species and the efforts to protect them. Tragically, there are thousands of species to choose from, each conservation effort as scientifically fascinating and ethically complex as the next. My goal hasn’tbeen to write comprehensively about the field of conservation; instead I’ve focused on dramatic cases of animals that are on the precipice of dying out or have already vanished. The extreme nature of these stories crystalizes the questions at the heart of our evolving morals and relationship to the natural world. How can humans coexist with species in the modern world when our existence and their survival so often appear pitted against one another? What should we preserve of wilderness as we head toward a future of incred- ible technological control over biology? Is nature here to serve our interests, or is its independence worthy of protection? I discovered that contrary to a common perception that much of biology has been explained, scientists are making new and incredible discoveries today that give us a glimpse into the complex relationship between genes, ecology, and evolution. And at a time of rapid environmental change on earth—as industrialization, globaliza- tion, and human sprawl go unchecked—these discoveries are much more than intellectual marvels; they present clues as to how we might prevent snuffing out the existence of other species.
Until very recently, humans never really cared much about whether species disappeared. History is littered with our indifference—dodo birds, great auks, 24-rayed sunstars, dusky seaside sparrows, Bernard’s wolves. For most of human civilization, no one really believed species could go ex- tinct. The environmental ethic planted in me as a kid probably wouldn’t have made sense even a hundred years ago to most people, who generally believed the earth’s bounty was intended for the benefit of human survival. It wasn’t until the early twentieth century—following the work of individu- als such as John Muir, Henry David Thoreau, and Aldo Leopold—that an ethic in which species were valued was born in the modern mind. When the environmental movement gained traction in the 1960s, the linchpin in the argument to save species was the threat of their extinction. Extinction, it has been said, is the middle name of conservation biology, a discipline that coalesced in the late 1970s at a time when the impacts of humanity’s dis- turbance of the earth’s ecosystems were manifesting themselves and docu- mented by scientists. This era has been described as a new geological epoch in which humans are a force of nature. Called the Anthropocene, its Noahs are conservation biologists, people who dedicate their professional lives to saving species.
The field of conservation biology is a crisis discipline; Michael Soulé, one of its earliest visionaries, wrote that its relationship to the biological sciences is analogous to that of surgery to physiology and war to political science. Facing a Sixth Extinction, it’s no surprise perhaps that conserva- tion biologists can be a gloomy bunch. Conservationists themselves have said that the field breeds a culture of despair. And at times, their pessimism threatens to undermine the cause. “A society that is habituated to the ur- gency of environmental destruction by a constant stream of dire messages from scientists and the media will require bigger and bigger hits of catastro- phe to be spurred to action,” wrote biologists Ronald Swaisgood and James Sheppard in 2010.
The fact is, few of the dire predictions I heard as a kid about the Sixth Extinction have come to pass. It’s generally thought that individual species last on average about a million years, and the idea that we are in the midst of a sixth mass extinction is based on an estimate that extinction rates have increased above this background rate. In 2000, the United Nations’ Mil- lennium Ecosystem Assessment estimated that extinction rates are now as much as 1,000 times this “normal” background rate and could increase to 10,000. But in the last 500 years, the number of species that have completely disappeared, what is known as a “true extinction,” is less than 900. Some analyses show the rate of extinctions among birds and mammals has actu- ally decreased since a peak in the eighteenth and nineteenth centuries; in 1900, they were going extinct at a rate of 1.6 per year, but that number has dropped to 0.2.
What’s really going on? If we are in the midst of the Sixth Extinction, why aren’t more species disappearing? Scientists know about this discrep- ancy between estimated extinction rates and actual extinctions and have chalked it up to something called the “extinction debt,” the idea that spe- cies can be “committed” to extinction because of the loss of their habitat or shrinking population size, but can take a while to actually go extinct. But a few years ago, two researchers, Fangliang He and Stephen Hubbell, realizedthe discrepancy was in part due to flawed math. The common formula used to estimate species loss as it relates to habitat destruction can inflate extinc- tion rates by as much as 160 percent. When He and Hubbell published their findings in 2011 in Nature, it was tricky news to deliver and created much controversy.
A few of years later, the journal Science published a paper whose authors further challenged the perception that untold numbers of species are disap- pearing before they can be discovered or named, a concern partly based on an oft-cited statistic that there are as many as 30 million to 100 million species on earth. Instead, the authors argued that there are in all likelihood around 5 million species on earth. “A meeting of conservation biologists or ecologists is hardly complete without worries about extinction rates, that many millions of species are yet to be discovered, and that the taxonomic workforce is decreasing,” wrote the authors. “We do not dispute that we are in a human-caused mass extinction phase with many species committed to extinction, but actual extinctions have been fewer than arguably expected. With a realistic surge effort, most species could be named within the present century.”
Undoubtedly, it’s good news that current extinction rates have largely been overestimated. But the fact that extinctions aren’t occurring at the rate previously believed can misconstrue the problem of habitat loss. Wild, untrammeled places are disappearing, and, with them, wild creatures in- dependent from human influence. In 2009 the European Commission and World Bank published a study that showed a mere 10 percent of the earth’s land today qualifies as “remote,” meaning it takes more than forty-eight hours to travel to it from a city. As humans and their activities have spread across the globe to extract resources, plant crops, and build cities and roads, thousands of species inhabit slivers of their previous ranges, surviving in isolated populations with few places to expand and faced with a loss of ge- netic fitness and an increased vulnerability to climatic shifts, disease, and natural disasters. Tigers, for example, inhabit less than 7 percent of the space they inhabited a century ago. Caribou have lost half of their historic range in the last 100 years. The World Wildlife Fund (WWF) estimates that, on average, vertebrate species populations have shrunk by half since 1990. An- thropogenic global warming has exacerbated the problem of disappearing habitat and shrinking abundance. Few landscapes around the world remain untouched by climate change today. And as they have for millennia, changes in climate are acting as selective pressures on species. For those animals that can’t withstand changes to their environments, migrate or adapt fast enough, their survival often depends on human intervention. An estimated 4,000 to 6,000 vertebrate species will need captive breeding over the next 200 years in order to mitigate extinction threats. Faced with these emer- gencies, the urgency to do something to save these species seems like a good ethical argument for action. But what actions we take have enormous con- sequences for the evolution of species.
When Darwin published On the Origin of Species in 1859, he believed that evolution through natural selection was a gradual process that took place over millions of years. But species such as the White Sands pupfish of New Mexico, which I write about in this book, have shown in recent years that natural selection can occur at rapid speeds, over mere decades. What this means is that humans are in the midst of an unplanned experiment of influencing the evolution of the planet’s biodiversity. The same forces driving extinctions—anthropogenic global warming, degraded habitats, overexploitation, disease, invasive species—are shaping the evolutionary trajectories of species. And which animals we prioritize, and how we choose to save them, tinkers with the biosphere as a whole.
The predominant thinking in conservation biology has been that pre- venting extinctions and hoping species will return to a fully conserved state—meaning free of direct human management—is enough. In an era of climate change, conservationists are realizing this is no longer a realistic expectation. Returning to a prelapsarian state of untouched wilderness, if one ever truly existed, is impossible. “It’s hard to future gaze to the next few hundred years, but unfortunately I think that’s what is going to hap- pen: life on this planet will likely be managed,” Brad White, a conservation geneticist, told me. “It might not be as totally managed as a zoo or farm ani- mals, but we are getting to that point.” The evolutionary ecologist MichaelKinnison described it this way to me: “Early on, the goal was to save the organisms from the environment. Bring them into captivity, and if you treated them nicely and not too biased in how you bred them, it won’t be an issue. Now there is much more of an understanding that organisms will adapt to those environments. In the process of trying to save them, we change them.” The irony of this age is that often the more we intervene to save species, the less “wild” and autonomous they become.
The looming ethical question is now whether or not humans, recognizing their evolutionary impact on species, should begin to consciously direct or engineer evolution in the direction they want it to go. Sometimes called prescriptive evolution or directed evolution, it might take the form of imbuing a species with characteristics that can help it survive environmental impacts down the road; translocating animals; or creating new, more resilient hybrids. Engineering biological processes in this way represents a kind of devil’s bargain for conservationists, who have traditionally separated people and nature. “When you are talking about messing with evolution, you are talking about the heart and core of what is special about this planet,” said Scott Carroll, a biologist and founder of the Institute for Contemporary Evolution, in an interview. But Carroll, a leader in the nascent field of applied evolutionary biology, responds to skeptics of prescriptive evolution by pointing out that we are doing it anyway. “It’s happening in this unplanned, unaware way in every living and breathing moment. We’re proposing a more thoughtful way. I don’t think we can come up with a sustainable relationship to the planet if we don’t become cognizant evolutionary organisms.”
The most explicit form of human bioengineering may be de-extinction, the ability to bring species that have already disappeared back to life with the goal of one day reintroducing them to their historical range. The technology of “resurrection science” is real and upon us. Scientists have not only successfully cloned endangered animals such as the European mouflon and the African wildcat, they are also working to bring back animals that are already extinct. In 2009, Spanish scientists successfully resurrected the Pyrenean ibex in the womb of a surrogate, though the animal lived just a few minutes after birth. International efforts are underway to bring back mammoths. These attempts to repopulate the modern landscape with extinct fauna rest on an intriguing ethical argument: that humans have a moral responsibility to make amends for overexploitation by our ancient and recent ancestors.
Take the case of the passenger pigeon, whose potential de-extinction has become symbolic of both our incredible faith in science to solve our ecological problems as well as a metaphysical predicament. Is a bird born of human ingenuity in the laboratory the same as a bird born of natural selec- tion in the wild? Or is it a case of what sociologists call bio-objectification, defined as the process by which life is made an object by humans? In 1982, Robert Elliot penned a paper called “Faking Nature” that rebuked the idea that an ecosystem disturbed or damaged by humans could be restored to its original state or has equal value to wilderness. Nature, wrote Elliot, is “not replaceable without depreciation in one aspect of its value which has to do with its genesis, its history.” It seems that today we have to decide whether that genesis in the wild is something we value.
Some scientists see de-extinction as irrelevant to the real grunt work of fighting for the survival of species. “For people who are doing this work, the passenger pigeon stuff is just an offensive conversation,” one biologist told me. “It’s publicity for newspaper articles.” There is real concern that the very idea that de-extinction is possible will weaken the will of the public and policy makers to protect endangered species or habitat. I found the individuals working on de-extinction projects to be brilliant, and a few downright inspiring. But not many have shown how we will put resurrected animals back into the world at a time when humans can barely coexist with extant species. Florida panthers were once thought to be extinct in the mid-twentieth century. By the time a remnant population was discovered by a legendary predator hunter in southern Florida, the animals had characteristics of severe inbreeding. After a genetic rescue operation was carried out in the early 1990s, the number of Florida panthers increased, but the animals today are limited to a paltry fraction of their former habitat, bordered on all sides by Florida’s booming population. “It’s a success story because the panthers are sturdy, but they are raising them in a cage,” Rocky McBride, someone who has tracked the panthers and other predator species for decades, told me.
After immersing myself in stories about extinction, the term Sixth Extinction has begun to feel unhelpful for grasping the scale and nature of the problem of diminishing biodiversity today. It is a monolithic idea; many of us are conscious that something terrible is happening to earth’s creatures even as the complexity of the problem eludes our full comprehension. Indeed, the idea of mass extinction can be so overwhelming, eliciting feelings of guilt and fear, that it eventually becomes an impotent fact in the same way that a million deaths is a statistic rather than a tragedy. In the stories that follow, I’ve tried to give flesh to a phenomenon that haunts the periphery of our awareness but is rarely seen or experienced directly. These stories are about just a handful of the animals that are on life support today, others that have already disappeared, and the people who discover, study, track, hunt, love, obsess, philosophize, save, and try to resurrect them.
Resurrection Science by M R Connor (St Martins Press, 2015)