Book in Brief: How to Clone a Mammoth

“Will there ever be a real Jurassic Park?” I’ve heard this question more times than I can count. The answer is always “No“. Aside from the problem of getting a viable clone to develop inside a bird egg – one that scientists haven’t cracked yet – DNA’s postmortem decay happens too fast to give us any hope of saying “Bingo! Dino DNA!” someday. But just because it won’t work for Tyrannosaurus doesn’t mean that it’s impossible for other forms of life. In How to Clone a Mammoth, ancient DNA expert Beth Shapiro offers a thrilling tour of the science that might – might – recreate lost worlds from the not-too-distant past.

how-to-clone-a-mammothThe book’s title is a bit of a bait-and-switch. On the very first page, Shapiro explains that for long-extinct organisms such as “the passenger pigeon, the dodo, the mammoth – cloning is not a viable option.” If at all, these organisms are going to come back to us piecemeal as revived genetic material expressed in hybrid creatures that may, or may not, look like the lost species. And this cuts to the core of what de-extinction is really all about.

From a purist’s perspective, extinction really is forever. It’s impossible to recreate lost species exactly as they were, down to every last gene and quirk of behavior. But with a broader definition of de-extinction – creating organisms that can fill vacant ecological roles – an elephant with a touch of mammoth trundling around the Arctic steppe would count as what Shapiro dubs an unextinct species. This is the goal of de-extinction efforts – not to recreate extinct species down to the finest detail, but to generate organisms that rehabilitate ecosystems. Not so much resurrection as carefully-crafted reinvention focused on ecosystem-scale repair.

As a researcher who is shaping this field, Shapiro is the perfect guide to the ongoing discussion about de-extinction. While many news items and conference presentations have focused on the technology required to recreate extinct life, Shapiro carefully considers every step along the journey to de-extinction, from choosing a species to revive to making sure they don’t become extinct all over again. As Shapiro says herself, she’s a realist rather than a cynic, and her finely-honed prose cuts through the hype that has clouded the debate around whether or not we should be striving to recreate lost species when so many living species are hanging on by the barest thread.

In fact, Shapiro uses the tension between those advocating for the return of extinct species and critics who argue that the effort would be better spent saving today’s imperiled organisms to propose a third option that has barely been discussed. Whether or not proxy mammoths, dodos, or sabercats come back, exploring such possibilities may give conservationists new tools to manage and assist threatened species and ecosystems. We’re already carrying out conservation triage on the weak and wounded, so why not use every tool at our disposal to sustain – and perhaps even improve – what we’re already managing by hand? Or, as Shapiro writes near the end of the book, “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.”

Will genetically-modified pseudo-mammoths or passenger-ish pigeons be the first symbols of a new age in conservation? That’s still unclear. But even if we never see shaggy elephants or the shade cast by immense pigeon flocks, de-extinction research already underway has the potential to both tell us about the past and provide us with new tools to decide the future shape of nature. Whether you’re all for de-extinction or against it, Shapiro’s sharp, witty, and impeccably-argued book is essential for informing those who will decide what life will become.

Does a Woolly Mammoth Need a Lawyer?

Shelley Estelle, Presidio Trust . via Flickr [Click on image for link]
Shelley Estelle, Presidio Trust. via Flickr Click on image for link
In 2009, a biologist named Daniel Gluesenkamp was driving through San Francisco when he saw a ghost. Draped over a bluff by the side of the road was a twenty-foot wide shrub festooned with cream-colored flowers. Gluesenkamp immediately recognized the plant as Franciscan manzanita, or Arctostaphylos hookeri franciscana. He was astonished, because it had been considered extinct in the wild for decades. The last known wild Franciscan manzanita had been bulldozed in a graveyard in 1947.

Before 1947, a few clippings of Franciscan manzanita had ended up in nurseries. Today you can buy the plant online. But the nursery form is the result of hybridization and extreme breeding; it’s now about as much like wild Franciscan manzanita as a German shepherd is like a wolf. It’s unlikely it could survive in the wild anymore. For thousands of years, wild Franciscan manzanita had grown luxuriantly in the prairies that carpeted much of the California coast. Now the wild plants were all gone–or almost, it turned out.

Before Gluesenkamp’s discovery, the U.S. government officially listed Franciscan manzanita as extinct in the wild. But then three organizations–the Wild Equity Institute, Center for Biological Diversity, and California Native Plant Society–petitioned the U.S. government to change its status. In 2012, the Fish and Wildlife Service agreed to the request and reclassified Franciscan manzanita from extinct to  endangered. Its known wild population was precisely one.

This wasn’t exactly the original plan for the Endangered Species Act when it was enacted in 1973. It was intended to protect species that were moving in the other direction, from healthy populations towards extinction. But once the single wild Franciscan manzanita plant came to light, the government decided that it deserved protection, too.

If that single surviving plant remained where it was, it would soon be destroyed in a highway renovation project. And so the plant was hoisted out of the ground and moved to a city park. Cuttings from the plant are now growing  in nearby botanical gardens. The Fish and Wildlife Service has identified hundreds of acres in the San Francisco area as critical habitat for Franciscan manzanita. Eventually, the cuttings may be reintroduced into those fragments of its former range.

The Franciscan manzanita’s story isn’t just a tale of fortunate rescue. It may also become a legal precedent for how the government deals with a more science-fiction-like situation. As I wrote in National Geographic in April, scientists are actively working on ways to bring extinct species back to the planet. If the Franciscan manzanita can gain government protection, then what about passenger pigeons? What about mammoths? What would the legal status of a saber-toothed tiger be?

In the January 2014 issue of The Stanford Environmental Law Journal–normally a place where you can read sober articles on fracking regulations and forest health–three lawyers explore this prospect. Their article is entitled, “How to Permit Your Mammoth: Some Legal Implications of ‘De-Extinction.'” (The authors are led by Norman F. Carlin, who has a Ph.D. in evolutionary biology and now practices environmental law.)

Courtesy of Mike Tyler
Courtesy of Mike Tyler
Southern gastric brooding frog

How the government deals with de-extinction may depend on how scientists bring it about. At the moment, there are a few different methods on the drawing board. The most straightforward one–at least in the view of Carlin and his colleagues–would involve cloning. As fellow Phenom Ed Yong explained in March, Australian scientists are trying to bring revive a vanished species of frog by thawing frozen cells that were taken from the animals before their extinction in the early 1980s.  The scientists are putting the extinct frog’s DNA into eggs from closely related species and coaxing the eggs to develop into embryos. If they can get the frogs to develop into adults, the animals could start reproducing and build a growing population.

Carlin and his colleagues think that a population brought back from oblivion this way would immediately deserve to go onto the list of endangered species. “The central purpose of the statute is to identify, protect, and promote the recovery of precisely those species facing the greatest risk,” they write. “None has faced greater risk than a species that actually has gone extinct.”

But in order for a revived species to survive, it will need help. You couldn’t just toss a few tadpoles down the nearest sewer grate and expect them to handle things from there. They’d need protected land, safeguards to defend them against devastating diseases, and perhaps a long-term captive breeding program to deliver enough new animals to get the population off the ground. Otherwise, a revived species could quickly suffer an unprecedented fate: a second extinction.

In theory, a species could gain this official protection as soon as scientists produced a single individual. A single individual may not seem to warrant being called a species. After all, a healthy species is made up of thousands of individuals and has lots of genetic variation. But if the Franciscan manzanita serves as an example, Carlin and his colleagues argue, the government could grant protection to a single individual.

Even if a revived species did gain official protection, however, it may not necessarily see the outside of a laboratory. The government would need to judge the risk of releasing it into the wild. This would not involve a government official played by Jeff Goldblum standing up and shouting, “Hasn’t anyone seen Jurassic Park?” The serious risks that de-extinction might pose would be for other animals and plants, not people.

Carlin and his colleagues suggest that regulators could follow the example of the Florida panther. When conservation biologists set out to save the dwindling population of panthers in Florida, they decided to bring panthers from Texas to increase their genetic diversity. Before the biologists could carry out this plan, though, the government first had to determine the risk of such an introduction. Would the Texas cats bring a disease that would kill the ones in Florida? The answer, regulators decided, was no.  The Texas panthers were delivered, and they’ve been a boon to the Florida population.

The passenger pigeon is one of the top deextinction candidates, but would the revived birds be able to thrive in the wild? Image from Wikipedia.
Passenger pigeon.  Image from Wikipedia.

In some cases, in other words, the existing rules would be good enough for the government to make decisions about de-extinction. But their decisions will get tougher if species are revived in less direct ways than cloning. Nobody froze a passenger pigeon before the species became extinct in 1914, for example, and so Ben Nowak of the University of California at Santa Cruz and his colleagues have proposed reverse-engineering a closely related pigeon species instead.

The first steps in this process are already underway. Nowak and his colleagues are gathering fragments of DNA from preserved museum specimens and combining their sequences to reconstruct much of the passenger pigeon genome sequence. They can then compare its genome to those of close relatives, like the band-tail pigeon, to get a sense of how the passenger pigeon evolved to become so distinctive.

Even if Nowak and his colleagues created a perfect copy of the passenger pigeon genome, it wouldn’t be possible to synthesize a matching DNA molecule. Technology today only offers the possibility of synthesizing segments of DNA and inserting them into the genome of a related bird. If scientists identified the key segments that made passenger pigeons distinct from other species, they could, theoretically, alter a bird like a band-tailed pigeon so that it became in effective passenger pigeon.

Carlin and his colleagues question whether such “facsimiles,” as they call the hypothetical creatures, deserve to be called passenger pigeons. If genetic authenticity is required, then they may not make the grade. In fact, government regulators might look at them instead as genetically modified organisms–a banded pigeon engineered with passenger-pigeon qualities. If that’s how things turn out, then a different set of laws will come into play–ones that are used to evaluate everything from bacteria that churn out human insulin to zebrafish that glow with jellyfish genes.

The U.S. government can set different levels of control for a genetically modified organism. It may be intensely regulated, for example, or the government may decide that there’s no risk to the environment if it gets into the wild. Today, for example, the U.S. Department of Agriculture released a draft environmental impact statement for genetically modified seeds from Dow AgroSciences. Part of their Enlist Weed Control System, these corn and soybean plants are engineered to withstand a weed-killer called 2,4-D. Today’s report could open the way to deregulating the seeds, which would lead to their commercial development. Farmers could plant them without worrying about keeping the plants from spreading in the environment. Carlin and his colleagues suggest that the same process could be adapted to evaluate de-extinction facsimiles.

Carolina parakeet. Wikipedia
Carolina parakeet. Wikipedia

There’s another way in which Enlist seeds could be relevant to de-extinction: they’re patented. An environmental group that wants to bring back an extinct sea cow to the Pacific may not have any interest in patenting the animal. But there might well be corporations that get interested in doing so. Carlin and his colleagues suggest, for example, that bird-lovers might pay top dollar for their own Carolina parakeet, a gorgeous bird that became extinct by the 1920s. Two prominent advocates have already formed a de-extinction company, called Ark Corporation that might use technology developed for bringing back extinct species to devise new livestock breeds.

Can you patent a mammoth? Carlin and his colleagues find this to be a very tricky question, thanks to the trickiness of the patent system. Congress has stated that “anything under the sun that is made by man” should be patentable. That statement has a nice poetic ring, but it leaves us to decide what “made” means. The Supreme Court has ruled that genetically engineered organisms can be patented if they have “markedly different characteristics from any found in nature.” If a company makes woolly mammoths by reverse engineering an Asian elephant, they might be able to argue that it’s so unnatural that it can be patented. But if scientists found an exquisitely preserved frozen mammoth egg and reared it into a full-grown mammoth (dream with me here, people), then it might not be patentable. It would by revived by man, not made by man.

While Carlin and his colleagues delve into fascinating detail about the legal future of de-extinction, they make it clear from the outset that they’re not dealing with the ethics of it. As intriguing as de-extinction can be in theory, critics have attacked it as a foolish distraction from the true horrors of extinction going on right now around the world.  (I’d recommend reading this strongly critical post by fellow Phenom Brian Switek.) These critics may find a discussion of the laws governing de-extinction to be an equally pointless distraction. But just because they don’t like de-extinction doesn’t mean that someone else won’t try it. And it’s those conflicts that laws are supposed to sort out in a democracy. “How to Permit Your Mammoth” is a first step towards preparing for the conflicts that de-extinction may well bring.



De-Extinctions and Straw Men

In my feature on de-extinction in the April issue of National Geographic, I tried to capture the debate in the scientific community about whether we should try to bring vanished species back to Earth. It’s been gratifying to see a spirited, sustained conversation going on ever since. The prospect of de-extinction raises important issues that have to be grappled with. Is it better to spend money trying to revive a mammoth or to secure a vast swath of rain forest? Are objections to de-extinction driven by a flawed notion of what’s natural? Would it make more sense to use the emerging tools of biotechnology to prevent endangered species from disappearing, rather than attempting to bring back the extinct ones?

But I’m frustrated by a column by George Monbiot that just appeared in the Guardian, entitled, “Resurrecting woolly mammoths is exciting but it’s a fantasy.” Monbiot singles out National Geographic for scoffing, declaring,

the double-page painting published by National Geographic in April, depicting tourists in safari vehicles photographing a herd of Siberian woolly mammoths roaming the Siberian steppes, is pure fantasy: the animals it shows are mumbo-jumbos.

(We Yanks use mumbo-jumbo to refer to gibberish, but after reading Monbiot’s piece, I did some dictionary-ing and discovered that the Brits use it to refer to a meaningless idol.)

It’s not Monbiot’s position that bothers me. In my article, I wrote about harsh critics of de-extinction as well as advocates. It’s the way he frames his argument at the outset:

There is an obvious, fatal but widely overlooked problem with de-extinction. 

Wow! Both obvious and fatal. Not just obvious and fatal, but also widely overlooked! What could this problem be, a problem that conservation biologists and molecular biologists who are exploring de-extinction have somehow failed to notice, a problem that Monbiot is here–at last–to unveil?


The scarcely credible task of resurrection has to be conducted not once but hundreds of times, in each case using material from a different, implausibly well-preserved specimen of the extinct beast. Otherwise the resulting population will not be genetically viable.

Really? That’s it?

I felt a distinct lack of surprise at Monbiot’s big reveal.  That’s because I had addressed this very issue in my own article four months ago, noting that reviving a single animal is not the same as bringing back an entire species.

But I didn’t go so far as saying that this was a “fatal” problem, because I discussed the issue with the scientists I interviewed. You’d think from reading Monbiot’s column that these scientists hadn’t the faintest clue of this problem. I picture them sitting in front of their screens, reading Monbiot’s revelations, and smacking their foreheads all at once, roaring, “Of course! How stupid of us!”

You’d have to be a truly stupid scientist to not be aware that the long-term viability of a species depends on a genetically viable population. If a small population is only made up of nearly genetically identical individuals, they run the risk of inbreeding, which can make them unhealthy, vulnerable to diseases, and even infertile.

The scientists exploring de-extinction are aware of this challenge, and they have actually given this matter some thought. They have ideas about how to deal with it. There’s a good debate to be had over whether those ideas could really work in practice, but Monbiot shows no signs of being familiar with them.

Monbiot is arguing that de-extinction cannot work, period, because it would require discovering an intact cell for every individual animal or plant scientists wanted to produce. There are several reasons why this is wrong. For one thing, scientists already have the technology required to engineer diversity into a species.

Museums have hundreds of preserved passenger pigeons, for example, and those birds are not clones of one another. By sequencing the DNA from a number of passenger pigeons, scientists could learn about the genetic diversity of the species. Based on the experiments scientists are already doing on animal cells, it’s conceivable that researchers could synthesize gene variants and plug them into the genome of an extinct animal. By engineering the genomes of the pigeons, scientists would create a flock containing some of the genetic viability that existed before the species became extinct.

If scientists can produce a few dozen genetically diverse passenger pigeons–or gastric brooding frogs, or thylacines, for that matter–it’s an open question whether those creatures could seed a sustainable population. Monbiot seems to be down on the whole idea of restoring small populations. He points to European bison, which have gone from 54 animals to 3,000, but which still have trouble with inbreeding.

But there are more heartening stories, too. Northern elephant seals were hunted down to the same population level, and today their numbers are up to 160,000.

Now we’ve drifted off the original course, though. We are no longer talking about de-extinction, but about the broader question of captive breeding. There’s another good debate to be had about whether to save the black-footed ferret and the California condor. But I guess it’s not as fun as shouting mumbo-jumbo! 

Reinventing the Mammoth

The first groaner of the TEDxDeExtinction conference cropped up less than an hour into the program.  Paleontologist Michael Archer was on stage, wrapping up his talk on possibly recreating the gastric brooding frog and the thylacine – two species totally lost from Australia in recent time. Archer laid out the technological particulars of the plans, as well as where the animals might live, but at the end he took a turn for the transcendentalist in justifying the difficult endeavor to resurrect these creatures. Since our species played a prominent role in wiping out both species, Archer argued, we have an obligation to “restore the balance of nature that we have upset.” If I had brought a flask with me, I might have taken a strengthening sip of whiskey right then.

There is no such thing as “the balance of nature.” If sifting through the fossil record has taught me anything, it’s that change is the rule. Balance is only a temporary illusion created by the difficulties of envisioning life on a geological scale. That, and quite a few conversations with practically-minded ecologists and biologists, means that I’ve become a bit allergic to snuggly phrases that are often trotted out to emphasize the inherent goodness of nature – whatever “nature” means – in a way that suggests we can simply restore the complexity of life to a stable state that the ghosts of Thoreau, Emerson, and Muir would honor us for. And the irritation of that line kept with me throughout the rest of the day. Perhaps the closing appeal to the balance of nature was a trifling throwaway, yet that one line underscored the problematic nature of the major proposal the assembled speakers and guests had been called to consider – that we can, and should, resurrect lost life to take some of the tarnish off our ecological souls. The concept falls under the banner of “de-extinction.”


The Promise and Pitfalls of Resurrection Ecology

Every species becomes extinct eventually. Some leave descendants that continue the evolutionary proliferation of life that kicked off on this planet over 3.5 billion years ago, but no parent species is immortal. Life on Earth is in continual flux, with new lineages emerging as others die back.

But what if we could resurrect lost species? And even if we developed the technology to do so, are such efforts wise during a time when the same attention and energy could be applied to preventing extant species from slipping away? This Friday, researchers are going to converge at the TEDX DeExtinction symposium, partnered with National Geographic, to discuss the possibilities and pitfalls of reviving species that have been lost over the past 12,000 years.

The woolly mammoth – the shaggy Ice Age icon that persisted until a scant 3,700 years ago – is probably the most charismatic “deextinction” candidate. For decades now, scientists have been considering how the lost proboscidean might be brought back through cloning, and we’re continually told that the necessary advances to accomplish the task are just around the corner. (Although, much like a Windows software release, the debut of woolly mammoth 2.0 has long been delayed. I’m not optimistic about estimates that we’re only four or five years away from squeeing over the photos of the first cloned baby mammoth.) But the woolly mammoth may be more of a symbolic conversation-starter that has obscured other Lazarus-wannabes, including the Tasmanian tiger, passenger pigeon, Steller’s sea cow, and the Xerces blue butterfly.

These candidate species, the “Revive & Restore” project says, were selected according to three sets of criteria. These requirements run the gamut from the squishy and snuggly – “Is the species missed?” – to matters of technological knowhow and whether the species is “rewildable.” What seems missing, or at least glossed over, are the ecological and ethical implications of reviving these lost species, and the focus on charismatic species has skewed attention towards animals that may not actually be good selections for resurrection.