SHOULD WE?
On March 15, 2013, a TEDx event was held at the National Geographic Society headquarters in Washington, DC, to celebrate and inaugurate the idea of de-extinction.1 The event coincided with publication of Carl Zimmer’s National Geographic Magazine cover story, “Bringing Them Back to Life.”2
On March 16, 2013, “de-extinction” hit the headlines like only new wars, missing airplanes, or resurrected mammoths can. Those of us who were involved with the event anticipated that this might happen. Our biggest concern was to try to limit hyperbole so that our message could be heard by anyone who cared to hear it. Those among us who supported de-extinction—and not all of us in the program did—hoped that de-extinction would become a tool that the conservation community could add to their existing arsenal of defense mechanisms against contemporary extinctions. We worried, however, that we would instead be seen by this community as, at best, jostling to compete with them for already limited resources and, at worst, providing a convenient excuse for the rest of the world to care even less about protecting endangered species.
At a rehearsal on the day before the big event, Ryan Phelan and Stewart Brand, who organized the event, passed around a media package that contained concise and clear (and consistent) answers to what they predicted would be the most common questions. The night before the event, they and we (the speakers) hosted a select group of local and national media, politicians, and heads of conservation-oriented NGOs at an invitation-only kickoff event. With this, we hoped to persuade stakeholders that the science we would be presenting was real, that we cared deeply about and understood the historical and political context in which we were operating, and that we were very much aware of how our message might affect—both positively and negatively—conservation movements within the United States and internationally. We wanted to be clear that our intention was not to sensationalize science fiction but to engage stakeholders and the public in a reasonable, scientifically validated debate.
The TEDx event was brilliantly organized, academically interesting, and a lot of fun. My talk was not particularly positive about the prospects of bringing exact replicas of extinct species back to life. Other talks were more enthusiastic, predicting major advances in no time at all. Mike Archer, an Australian scientist who is leading a group called the Lazarus Project, presented brand new results that were released to the media in Australia during his presentation. Mike’s research team had just succeeded in creating embryos from frozen cells of the extinct Lazarus frog, which was an awesomely peculiar amphibian that swallowed its tadpoles and later regurgitated fully metamorphosed juvenile frogs. Although the Lazarus frog embryos did not live for more than a few days, Mike insisted, correctly, that this was a major step forward in Lazarus frog de-extinction. Ben Novak unabashedly displayed his obsession with the passenger pigeon by presenting a detailed plan for exactly how he was going to release them into the wild after they were brought back to life. Distinguished professors of conservation biology, philosophy, law, and ethics brought up orthogonal points relating to whether or not de-extinction was realistic, dangerous, or (and?) morally reprehensible.
The initial reaction to the TEDx event was mostly one of unadulterated excitement. The mammoth was going to be cloned! (Clearly, nobody paid attention to my presentation.) The passenger pigeon was going to darken the skies once more! (Everyone seemed to have forgotten Michael McGrew’s talk, during which he explained to the audience that birds cannot be cloned.) The world was going to be saved! (Perhaps no one remembered Stanley Temple’s talk, which highlighted the need for careful consideration of the ecological consequences of introducing an extinct species to an ecosystem that had continued to evolve in its absence.) George Church was going to change the world! (Yes, that’s probably true.)
Doom and impending catastrophe sell more newspapers, magazines, and documentaries than do happy visions of the future. This is not new to conservation scientists. Irreversible climate change, imminent extinctions, the disappearance of the forests and the animals in them—those are the topics of headlines. Solutions, success stories, reintroductions—these stories are relegated to the space beneath the classifieds. The headlines about de-extinction were clear. De-extinction is dangerous. Some scientists say it’s a bad idea. It could and probably will go horribly wrong, just like in Jurassic Park. And given that it is definitely happening and the mammoth is being cloned and passenger pigeons are about to darken the skies again and Lazarus frogs will soon be barfing up their babies, the public should be scared. The public should stop de-extinction from happening! At the very least, the public should make it known that they are aware of the sneaky, dangerous stuff going on in those ivory towers and that it doesn’t make them happy.
I started to get hate mail. I was both terrified and surprised by this. My presentation had been one of the most negative, pointing out, as I have in this book, all of the challenges facing those who wish to bring extinct species back to life. In my many media interviews that followed, I did my best to maintain a positive yet skeptical outlook. The media, with some exceptions,3 have often been less than appreciative of my skepticism. I’ve been in several interviews in which the interviewer spent a lot of energy trying to get me to say something sensational or controversial—as if “Yes, I am working with others to bring back something similar to the mammoth and passenger pigeon” is not sensational enough.
I also got fan mail. Several people wrote to congratulate us on our bravery and foresight. People offered to send us bones, teeth, and feathers that they’d found while gardening. Students wrote heartfelt letters begging to join the lab so that they could be involved with bringing back the passenger pigeon. Mike Sweeny, who is the executive director of Nature Conservancy in California, contacted me to see whether there was some way that his organization could help with de-extinction in California. There was a tremendous, positive outpouring of support.
The hate mail was equally sincere. I was accused of playing God. I learned that I was going to bring about the end of the world. I was informed that I was a menace to society and should be stripped of my academic credentials. One note even suggested that I should be the first meal for any saber-toothed cat that we managed to bring back.
Professional scientists don’t send hate mail, but they do publish hate papers. Several very smart, very highly regarded scientists came out in force against the de-extinction movement. Professor Paul Ehrlich is an eminent scientist at Stanford University and the president of Stanford’s Center for Conservation Biology. He is perhaps best known for his ominous predictions about what will happen to the world if human populations continue to grow as they are today. Ehrlich emphatically refused an invitation to attend a workshop at his own university that was sponsored and organized by Professor Hank Greely, an equally eminent law professor who specializes in biotechnology law. In fact, Ehrlich recommended so forcibly that no one in his department make the slightest pretense toward supporting the idea of de-extinction that not a single Stanford biologist was present at the meeting, despite the fact that it took place on their doorstep and aimed to address precisely the topics that infuriated Ehrlich.
Months later, Ehrlich agreed to a public debate of sorts with Stewart Brand, who, it turns out, had studied as an undergraduate under Ehrlich when Ehrlich first joined the Stanford faculty in 1959, and whom Ehrlich still considers to be a good friend. The debate was not a conversation but, instead, a pair of written essays that presented opposing views about whether de-extinction should go forward.
When I first read Professor Ehrlich’s essay, I was surprised by many of the issues he chose to highlight. What surprised me was that many of the problems he noted, while certainly valid, important, and deserving of consideration, are not unique to de-extinction. The problems he highlighted are the same problems that come up every time a new tool for biodiversity conservation is proposed, an embattled realm in which Ehrlich himself is no stranger. While Ehrlich begins his essay by taking issue with the financial cost of de-extinction, his more powerful objections are to the indirect but potentially more insidious costs—the potential costs to society, to endangered species, and to endangered ecosystems.
From the meanest to the most profound, all objections to de-extinction arise from genuine fears and deserve to be addressed. Below, I attempt to speak to those concerns that I hear most often or that I feel are the most central to the ongoing debate. Not every question can be answered, and this is one of the most troubling truths about de-extinction. Certainly, there will be costs associated with de-extinction, including costs that we have yet to imagine. I feel strongly, however, that there is one very important cost that Professor Ehrlich and the often-anonymous writers of hate mail fail to cite: the cost of doing nothing.
WE MIGHT REVIVE DANGEROUS PATHOGENS
Since we cannot know exactly why the last few individuals of an extinct species died, is there a chance that it was a dangerous pathogen that killed them? And if we bring these individuals back to life, might we also bring back that dangerous pathogen?
Probably not. In addressing this, it is important to consider where pathogens would be preserved. Most pathogens do not integrate into the genomes of the organisms they infect. Instead, they attack a specific part of that organism—the lungs, for example, or liver, or blood cells. If tissues could be revived from an extinct organism and those tissues happened to contain a pathogen, then it is possible that the pathogen could also be revived. One of the recent mammoth finds in Siberia contains what looks like blood, which contains what looks like blood cells. If this organism had been infected by a blood-borne pathogen, then this blood-like substance could have included what looked like cells from blood-borne pathogens (it did not, as far as I know). However, it has not yet been possible to revive cells from extinct species, as the genetic material within them is simply too degraded. This will apply to pathogen genomes as well. No recovered pathogen cell will be sufficiently intact that it is capable of coming back to life.
Genomes do contain some viruses that integrate into the genome. Our own genomes are full of such viruses, the vast majority of which are not harmful. If we were to extract DNA from a bone and sequence everything that was recovered, the mixed pool of extracted DNA would include DNA from the animal whose bone it was, DNA from infectious pathogens that were present at the time of death, and DNA from anything that got into the bone—including other pathogens—during burial and excavation. All of this DNA, however, at least all of it that is ancient, will be fragmentary and damaged, as expected for ancient DNA. Any ancient viruses or pathogens that were preserved within that sample would certainly not be in any state to be infectious.
DE-EXTINCTION IS NOT FAIR TO THE ANIMALS
This might be true. Animal welfare does need to be considered explicitly when developing a plan for de-extinction. In previous chapters, I outlined some of the ways that animals might be exploited or harmed in the course of this work. Some species—such as Steller’s sea cow—may be terrible candidates for de-extinction, simply because it would be impossible to resurrect them without causing unnecessary animal suffering. As technology advances, this may become less true. For example, technology that allows in vitro rather than in vivo gestation would eliminate the requirement for cross-species gestation. From an animal-welfare perspective, the captive-breeding stage is likely to be one of the most challenging steps of de-extinction. Better understanding of the basic needs of animals in captivity and of how we can minimize the effects of being raised in captivity once animals are released in the wild will be key to the success of de-extinction. These are areas of active research, and advances will come. As of today, the possibility that too many animals might suffer remains a serious obstacle to de-extinction.
WE SHOULD PRIORITIZE CONSERVATION OF SPECIES THAT ARE ALIVE TODAY
In 2014, I participated in a conference in Oxford, UK, on the importance of megafauna—both extinct and extant—in maintaining the ecosystems in which they live. The keynote speaker was George Monbiot, a journalist and environmental activist who writes a weekly column for the Guardian. Monbiot’s speech was a lively and impassioned plea to support rewilding in Europe. At an emotional apex and with tears forming in his eyes (at least in my memory), he roared angrily, “Those billionaires that are funding de-extinction—they should instead be investing their millions to introduce the Asian elephant to Europe!”
I agree with him about the elephants. One of Monbiot’s most salient points was that the European vegetation had evolved in conjunction with a type of elephant—a mammoth—and, since elephants are missing at present, we should put them back if we can find a place for them. I agree. If elephants, whose native habitat is dwindling, could be introduced into pockets of Europe where efforts are already under way to rewild, why not do so? Asian elephants might even survive without genetic manipulation in parts of Europe.
But the billionaires? Who and where are they? And may I have their number? As of this moment, I know of no de-extinction project that is being funded, much less being funded by billionaires. The biotech development that is going on in the Church lab is only possible because the technology itself has another purpose—specifically the purpose of curing human disease. Money for my group to sequence genomes from passenger pigeons and band-tailed pigeons has been cobbled together out of my small research budget from the University of California, some funds from private foundations that are dedicated to developing techniques for the assembly of ancient genomes, a donation of several thousand dollars from Revive & Restore, and voluntary time from people like Ben Novak, Ed Green, and others working in the group. The bucardo project has some support from a local hunting federation, but certainly not enough to fund an entire de-extinction project. If billionaires are investing in de-extinction, I haven’t heard about it. But I would like to hear more.
Should de-extinction compete for resources aimed at the preservation of living species and habitats? Absolutely not. Is de-extinction competing for resources with these organizations? Today, the answer is very clearly no. In 2014, the US government budgeted just under $414 million for all of its international conservation initiatives and exactly $0 for de-extinction research. Conservation International reports spending around $140 million every year, $0 of which is spent on de-extinction projects. The World Wildlife Fund spends around $225 million on its various international programs, none of which involve or are related to de-extinction.
The costs of later stages of de-extinction, including captive breeding and release and the long-term management of free-living populations, will be harder to tuck neatly away into the budgets of other projects. It is doubtful that breeding mammoths will lead to a cure for human genetic disease, for example, which makes it hard to justify mammoth-breeding expenses on a grant from the National Institutes of Health. When it’s time to breed mammoths, new sources of money will have to be found. These sources are likely to be different from those that fund existing conservation initiatives. People give to causes they care about, and different people care about different things. The people who care about the plight of polar bears or pandas will probably not be the same as the people who want to bring passenger pigeons back to life. Hopefully, as de-extinction as we perceive it gains momentum, this will lead to the discovery of new sources of funding for conservation initiatives and a strengthened focus on the creation and preservation of wild habitats.
While the idea that de-extinction may spark interest in conservation—more precisely, in funding conservation research—is attractive, it also highlights an important weakness in the present strategy to fund de-extinction research. Today, this research is being performed by scientists on species that the scientists find interesting. However, private individuals are being asked to fund the work. Just as the lion’s share (pun intended) of conservation funding goes to the most charismatic of endangered species, species will probably be selected for de-extinction based on their public appeal. People are likely to be far more interested in dodos and Steller’s sea cows than they are in extinct kangaroo rats and land snails, although kangaroo rats and land snails are arguably more critical to the stability of their ecosystems than either dodos and Steller’s sea cows were to theirs. Ultimately, our partiality toward charismatic megafauna will lead to a taxonomic imbalance among de-extinction projects that is not unlike the imbalance that exists in conservation work.
If de-extinction is to become a genuine weapon to be used in the war against contemporary extinctions, all sectors of society—and not just scientists—will need to work together to identify the resources to make it happen.
UNEXTINCT SPECIES HAVE NOWHERE TO GO
Unfortunately, many species that are candidates for de-extinction have no habitat in which to live. The more people there are in the world, the less space there is for other species. Deforestation and illegal hunting are significant problems in many parts of the world. If these are the problems that led to extinction in the first place, these problems must be resolved before that extinction can be reversed.
Some species require more space than it might be possible to find. Gray wolf populations are booming in Yellowstone National Park, where they are protected from humans. The park provides nearly 9,000 square kilometers of space for wolves, but this is not enough. As the wolves jostle for territory and dominance, they expand beyond the park’s borders. When they get out, they cause mayhem and get shot. When dominant wolves get shot, it upsets the pack structure and dynamics. Gray wolves cannot quite come to a sustainable equilibrium in a space the size of Yellowstone.
Finding sufficient amounts of suitable habitat will certainly present a challenge for some de-extinction projects. This should not, however, preclude further assessment of the suitability of other species for de-extinction. Nor should it deter efforts to improve habitat by removing invasive species or enforcing anti-poaching or anti-deforestation laws. On the contrary, highlighting this problem in the context of de-extinction may act as a beacon for new investment and new solutions, which would also benefit existing conservation projects.
RELEASING UNEXTINCT SPECIES WILL DESTROY EXISTING ECOSYSTEMS
To this concern, I respond with an emphatic “maybe.” Certainly, a thorough assessment of the environmental impact of releasing new species into the wild should be done before a de-extinction project begins. Assuming the candidate species for de-extinction is an animal, the assessment should include analyses of what and how much it is likely to eat, with which other species it will compete for resources, where and when it will sleep, by what means and how far it will move, what will eat it and what are the consequences of it being eaten, whether it will act as a vector for disease, and what effect it will have on nutrient cycling, pollination, the microbial community, and so forth. Regardless of how thorough and careful these assessments are, there will be unanticipated interactions between species and unanticipated consequences to the ecosystem. This is unavoidable. When the species went extinct, the ecosystem in which it was once a part evolved to accommodate its absence. Other species, sometimes even invasive species, moved in. Reintroducing the extinct species may upset the existing dynamics within that ecosystem, but to claim that that ecosystem will be “destroyed” might be going too far. Yes, species introductions change ecosystems—that is often the point of the introduction. To this end, a risk assessment will not ask whether an ecosystem would change (it would), but how it would change, how other species would be affected, and whether the reintroduced species would be sustainable within that ecosystem.
Completing such an assessment is likely to reveal that some species are poor candidates for de-extinction. Some species would be too destructive to fit within the confines of today’s people-dominated world; imagine sixteen-foot-tall short-faced bears wandering around downtown Los Angeles. Some species simply have nowhere to go; the Yangtze River dolphin cannot be placed back into its natural habitat unless there is dramatic improvement in the water quality of the Yangtze River. Some species may require more long-term investment than it is possible to secure. We may find that so little is known about the behavior and ecology of some species that the risks of environmental catastrophe far outweigh the benefits of their return to the ecosystem.
If a reintroduction does have catastrophic consequences, we could simply remove that species from the ecosystem using whatever means necessary. Re-extinction is certainly an extreme tactic, but it calls on expertise that we already know we have. Of course, it may not be that simple. Once an organism is released, it will start to affect the ecosystem into which it has been introduced. It’s doubtful that everyone will agree about whether these changes are good, or even acceptable. Society as a whole will have to decide whether removal is necessary, and this will not be an easy decision to make.
Consider the example of beavers in Great Britain. Until recently, beavers were extinct in Great Britain. Beavers were driven to extinction in Great Britain some 400 years ago by humans, who valued beaver fur and medicinal glands and loathed beavers. Beavers are destructive; they cut down trees and use these to build dams, which cause rivers and streams to flood. Dead beavers were better beavers, at least to sixteenth-century Britons, and so beavers disappeared. Then, in 2006, beavers were discovered living along the River Tay in Scotland. In early 2014, a family of wild beavers was spotted in Devon, in the southwest of England, playing in the River Otter. It is believed that both of these beaver populations were established after deliberate and illegal release from private collections.
Along the Rivers Tay and Otter, residents differ widely in how they feel about the beavers. Some residents are quick to identify the positive impacts they’ve seen on the environment since the beavers reappeared. They point out that, by building dams along the rivers, the beavers have created new habitat for frogs that lay their eggs in the shallow, slow-moving ponds formed by the dams. These frogs and their eggs are, in turn, an important food source for insects, birds, and fish, which some residents claim have increased in abundance since the beavers’ return. The beaver dams have also begun to reestablish local wetlands, which the residents hope may help to control flooding along the rivers. Other residents, however, dislike the beavers. These residents point out that beaver dams block migration routes used by salmon and trout, and may actually increase rather than mitigate flooding, with devastating consequences for riverside farms.
While beavers, fish, and agriculture coexisted in Britain for centuries, the British countryside has changed considerably over the last 400 years. Thanks to these changes, it is not at all clear that coexistence can resume.
So what to do? Should the illegally released beavers be removed from the British countryside, or should beavers be introduced to even more rivers? This has been a difficult question to answer. As a member of the European Union, Britain is under pressure to reintroduce native species that have been driven to extinction locally. The wild-living beavers may, in fact, already qualify for legal protection under EU laws. Within Britain, England, Scotland, and Wales get to decide for themselves what to do within their borders, and there is no consensus. Wales is considering allowing beavers to be introduced into the Welsh countryside, while the English government has established an official program to capture the beavers along the River Otter and remove them to captivity. Along the River Tay in Scotland, some 300 beavers now make their homes. The Scottish government is set to decide, soon, whether they get to stay.
The example above highlights yet another significant challenge that society will need to resolve if de-extinction is to move forward: when is it clear that a de-extinction experiment has failed? With beavers, the environmental impacts of release can be inferred from habitat in which the beavers still live. This will not be true when the organism to be released is completely extinct and, consequently, the risk that it all goes horribly wrong will be, admittedly, greater.
I want to circle back to the beginning at this point and restate something I said in the first pages of this book. While re-extinction is certainly an option, and one that quells the deepest fears of some de-extinction skeptics, I worry that people might resort to this drastic measure too quickly. Interactions between species may take years to develop. Ecosystems into which a resurrected species is introduced may become destabilized initially and only much later re-establish the interactions between species that were the goal of the de-extinction project. These experiments will take time, and I hope that we can be patient. It is natural, however, to fear what we do not know and cannot predict. Being patient will not be easy.
Concern about the appropriateness of hands-on environmental stewardship is not unique to de-extinction. Conservation strategies can be thought of as a continuum between entirely managed ecosystems (think “gardening”) and allowing nature to fend for itself (think “preserving”). De-extinction is a disruptive strategy and, as such, requires some amount of gardening. However, like other disruptive strategies—including rewilding, managed relocation, and island restoration—de-extinction can play a role across nearly the entire continuum. Some species will require constant gardening, while others will require little to no intervention to be sustainable once established. Regardless, all disruptive strategies are inherently risky, as there is always a chance that a heavy human hand may do more harm than good. Purely preservationist strategies are, however, also risky. What if sufficient habitat can’t be preserved? What if species do not re-establish populations in the habitat that is preserved? Few habitats have avoided completely the effects of human population growth, suggesting that, at some level, intervention has already occurred. Further intervention may be required simply to reduce the damage that has already been done.
Island restoration projects, such as two that are taking place off the coast of Mauritius, are proving that intervening can work. On Round Island and Ile aux Aigrettes, conservation biologists are working to remove invasive species and re-establish populations of native species. But there are problems. Native plants are slowly being replaced by invasive plants in the absence of the extinct giant tortoises that once thrived on the islands. The native plants grow slowly and close to the ground and have small tough leaves that are difficult for tortoises to eat. They also fruit when grasses—a main source of food for tortoises—are not abundant, which increases the likelihood that hungry tortoises would disperse their seeds. In the absence of giant tortoises, nonnative plants have outcompeted the tortoise-adapted native plants, many of which are now on the brink of extinction.
To restore the missing interactions between native plants and giant tortoises, the research teams introduced different species of giant tortoises that still survive in other parts of the Indian Ocean, hoping that these giant tortoises would functionally replace the extinct Mauritian giant tortoise. The introduced giant tortoises immediately took to their new habitat, preferring to graze on the non-native plants that lacked defenses against tortoise herbivory. They also ate the fruits of native species. Stands of ebony, which had struggled to survive in the absence of a large herbivore to disperse its seeds, have started to appear throughout the Islands.
IF DE-EXTINCTION IS POSSIBLE, THE RATE OF EXTINCTION WILL INCREASE
This moral hazard argument presents a horrible view of people. It assumes that that at the slightest (and I mean slightest) hint of a quick fix, no matter how not-so-quick and not-quite-a-fix it is, people will give up trying to preserve endangered species. Sure, legislation to protect endangered species is complicated, confusing, sometimes misguided, and too often out of date. But, it is hard to imagine that people who care about biodiversity conservation would suddenly stop doing so should de-extinction become possible.
Of course, there are many people who simply don’t prioritize biodiversity conservation, and others who have some stake in seeing species removed from protection. In these cases, one might imagine how the idea of de-extinction might be manipulated to further a specific political agenda. The notion that politics or big business might use biotechnology to manipulate rules, regulations, and public sentiment is, of course, not unique to de-extinction.
WE ARE “PLAYING GOD”
As an epigram to the first edition of the Whole Earth Catalog in 1968, Stewart Brand wrote, “We are as gods and might as well get good at it.” Like many of the ideas that motivate Stewart, this line, which he conceived while reading anthropologist Edmund Leach’s book A Runaway World, was meant to make people imagine, with bold optimism, a future that was different, pleasant, and full of wonder. But, he did not want them to stop there. Stewart wanted to motivate people to act, using that bold enthusiasm, to make real the future that they had just imagined.
Stewart’s issue with science and society, then and now, is their deference to the status quo. Their detachment. His argument is simple and positive: we can make a better future, but not by standing by and waiting for it to happen. We—everyone—must participate. It is our responsibility to use our intelligence and our advanced technology for good.
The “playing God” argument is not one that that has emerged in response to de-extinction but, instead, is an argument that arises frequently in response to technology that is new or not well understood. This argument can be religious, but it is often a metaphorical accusation—“playing God” may simply mean using powerful tools without understanding the full implication of those tools.
In the specific case of de-extinction, the accusation of playing God concerns human manipulation of nature. By engineering new organisms, by altering the structure of biological communities, and by altering the course of today’s extinction trajectory, we are messing with things that we simply don’t understand and therefore probably shouldn’t be messing with. Importantly, de-extinction does not mark the beginning of human manipulation of nature. With the earliest attempts at domestication of gray wolves in Europe some 30,000 years ago, our species began manipulating the genetics of other organisms to our advantage. Most of the food we eat has been genetically engineered—albeit by breeding and not by genome editing—to suit our tastes and to meet the growing demand for more. Species introductions, whether purposeful or accidental, have been happening since we first built boats and learned how to navigate from one place to another. And the extinction trajectory on which we are heading is, arguably, itself human induced.
I believe that what motivates this argument in the case of de-extinction is the fear of losing control. This is a reasonable concern. It is, however, a concern that should be expressed and addressed rationally, taking advantage of the scientific process.
THE PRODUCT OF DE-EXTINCTION WON’T BE THE SAME THING AS THE ORIGINAL SPECIES
That is correct. It won’t be the same.
In Stewart Brand’s half of his written debate with Paul Ehrlich, he writes: “If it looks like a passenger pigeon and flies like a one, is it the original bird?” My answer is no, it’s not the same, and by this point in the book it should be clear why my answer is no. Crucially, however, I don’t care that it’s not the same thing as the original, and I’m pretty sure that Stewart doesn’t care, either.
The task ahead is not to make perfect replicas of species that were once alive. First, it is technically not possible to do so and is unlikely ever to become technically possible to do so. Second, there is no compelling reason to make perfect replicas of extinct species. The goal of de-extinction is to restore or revive ecosystems, to reinstate interactions between species that no longer exist because one or more of those species are extinct. We don’t need to create exact replicas of extinct species to achieve this goal. Instead, we can engineer species that are alive today so that they can act as proxies for extinct species. We can revive adaptations from the past—adaptations that arose by chance and were refined by evolution—in species that are still alive today.
In fact, there is no reason to restrict this technology to de-extinction. If living species are threatened by a lack of diversity or by an inability to adapt quickly enough to a rapidly changing climate, why not facilitate their adaptation as well?
The American chestnut tree is a great example of the power of genome engineering in conservation. Around the year 1900, the accidental importation of a fungus from Asia wiped out nearly every single American chestnut tree. The airborne fungus kills the tree by forming cankers in the bark that cut off the flow of nutrients from the ground. New shoots may grow from surviving roots, but none of these escapes the deadly fungus. Thanks to genetic engineering, American chestnuts are now on the verge of making a dramatic comeback into the eastern deciduous forests of North America. Led by Bill Powell and Charles Maynard of the State University of New York in Syracuse, the American Chestnut Research and Restoration Project has genetically engineered several new strains of American chestnut that are increasingly resistant to the fungus. In 2006, this team planted the first fungus-resistant chestnut seeds in the wild. Today, there are more than one thousand genetically modified American chestnut trees growing in the state of New York.
A BRAND OF POSITIVISM
Regardless of how feasible it really is, de-extinction has succeeded in forcing us—by “us,” I am referring here to scientists who hope, as I do, that our research will have a positive environmental impact—out of our comfort zones, exactly as Stewart Brand envisioned it would. Stewart, of course, would like to see de-extinction do more than that. His goal is for de-extinction is that it will become “a reframing of possibilities as momentous as landing humans on the moon was.”4 Certainly, if it does become possible to resurrect extinct species or to coax living species to express extinct traits, our perception of what it means to be “extinct” will change fundamentally. The most momentous change, however, will be in our attitudes toward living species—this, I believe, is what Stewart is referring to when he speaks of possibilities reframed. Suddenly, we will have the technical know-how to engineer sustainability into threatened populations. Will improving rather than protecting species become the new objective of biodiversity conservation? If we turn to the past to identify traits that can be used to improve the plight of living species, where will we draw the line between preventing versus reversing extinction? And will we care?
This, I believe, is why people like me are so captivated by the idea of de-extinction. Not because it is a means to turn back the clock and somehow right our ancestors’ wrongs, but because de-extinction uses awesome, exciting, cutting-edge technology to take a giant step forward. De-extinction is a process that allows us to actively create a future that is really better than today, not just one that is less bad than what we anticipate. It is not important that we cannot bring back a creature that is 100 percent mammoth or 100 percent passenger pigeon. What matters is that—today—we can tweak an elephant cell so that it expresses a mammoth gene. In a few years, those mammoth genes may be making proteins in living elephants, and the elephants made up of those cells might, as a consequence, no longer be isolated to pockets of declining habitat in tropical zones of the Old World. Instead, they will be free to wander the open spaces of Siberia, Alaska, and Northern Europe, restoring to these places all of the benefits of a large dynamic herbivore that have been missing for eight thousand years. De-extinction is a markedly different approach to planning for and coping with future environmental change than any other strategy that we, as a society, have devised. It will reframe our possibilities.
De-extinction will, of course, be risky. We don’t know and cannot predict every outcome of resurrecting the past. The conservation success stories of the present day prove, however, that taking risks can be deeply rewarding. Removing every living California condor from the wild was an extraordinarily risky strategy to preserve the species, but one that undoubtedly saved them from extinction. Restoring gray wolf populations to Yellowstone National Park was both risky and, to a degree, unpopular, but the park is now flourishing in a way that it had not since its establishment in 1872, when wolves and other predators were actively exterminated. Allowing deer, cattle, and other wild animals to take over abandoned land in Europe was touted as both crazy and dangerous, but these reestablished wilderness areas stimulated a widespread shift in attitudes toward wildlife. They inspired new policies aimed at protecting natural spaces and the species that occupy these spaces. How will the world react when the first genetically engineered elephants are strolling casually through Pleistocene Park?
I can’t wait to find out.