Russian Scientists Are Trying to Revive Wooly Mammoths to Halt Siberia’s Warming Crisis

The prehistoric animals could diffuse the Arctic’s ticking carbon bomb

A woolly mammoth skeleton is displayed at Summers Place Auctions on November 26, 2014 in Billingshurst, England. Photo: Peter Macdiarmid/Getty Images

On a warm afternoon in the northeastern Siberian region of Yakutia, farther north than most humans care to live, Sergey Zimov stood below an eroding mudbank along the Kolyma River. He reached down by his feet and drove a metal rod into the spongy ground that sucked at his boots, hitting what lies a few feet beneath the surface: a layer of frozen soil that’s as hard as rock — and arguably as dangerous as dynamite.

Arctic permafrost holds up to 1,600 gigatons of carbon, roughly twice what’s in the atmosphere. Temperatures across the region are warming more than twice as fast as the rest of the world, and as this ground melts, it’s releasing masses of carbon that have been locked in frozen dirt for millennia. When it joins with the microbes in the air, the carbon oxidizes, entering the atmosphere as carbon dioxide and methane — the chief greenhouse gases that contribute to a warmer climate.

Current models suggest the permafrost could lose up to 20% of its stored carbon — and even that could take as long as 80 years. But disturbing signs are emerging that the rate of permafrost thawing is accelerating as the planet warms. A sudden collapse — or abrupt thaw, as scientists call this process — might create enough greenhouse gases to trigger a self-reinforcing climate feedback that would push the world past a dangerous tipping point and, eventually, into runaway warming.

Few know this silent menace better than Zimov. An ecologist by training, he has spent more than three decades studying warming in the Arctic, and was among the first to discover that its vast carbon stock posed a risk to the global climate more than two decades ago. To avert the threat, he has called for a radical solution: rewilding vast swaths of the Arctic with huge herds of bison, mammoths, horses, and other extinct species.

Zimov’s hypothesis is that, by simply trampling mosses and ripping out tree saplings, these large browsers would resurface the mammoth steppe, a grass-dominated ecosystem that quilted much of the northern reaches of Eurasia and North America until the end of the last ice age, about 12,000 years ago. That biome, Zimov argues, would help keep the permafrost frozen — and, he hopes, spare humanity from climate disaster.

In 1996, on lowlands near the former gold-mining town of Chersky, Zimov established a 36,000-acre demonstration project called Pleistocene Park. Over the years, he and, eventually, his son Nikita, fenced in small groups of bison, muskoxen, moose, yaks, horses, elk, and other herbivores they hauled in across the Arctic circle, from Denmark to Alaska. These days about a hundred animals roam the preserve.

Pleistocene Park is the ultimate test of Sergey Zimov’s theory. Grasses are better than mosses, shrubs, and trees at reflecting sunlight — so they would cause the ground to absorb less heat in the summer, when the Arctic sun stays high for weeks. During winter, grazing animals would tamp down deep snow, ensuring the ground is exposed to the bitter Arctic winter temperatures. Both factors would cool the land, helping permafrost stay frozen as temperature warms.

Early evidence — even without the mammoths — is promising. The park has already broken out of its original boundaries, eating its way into the dense and dark woods of the surrounding taiga. Inside, soggy grasses have replaced scraggly larch and moss.

“The difference is striking, particularly if you know the undisturbed state of the landscape,” says Mathias Goeckede, a research scientist with Germany’s Max Planck Institute for Biogeochemistry, who tracks carbon exchange between the earth and the atmosphere in a parcel a few miles downriver from the park.

Data collected by temperature sensors placed in boreholes show that average permafrost temperatures within the park’s grasslands are about 2 degrees Celsius colder than that in the surrounding area. The temperature difference, says Nikita Zimov, who is now in charge of the project, is “enough to keep the permafrost intact.”

To fully test their concept, though, the Zimovs would need to unleash hundreds of thousands of large herbivores across millions of acres of land, with changes in the landscape advanced enough to allow the new ecosystem to be self-sustaining. So far, the maintenance of the Pleistocene Park has required a lot of resources — and the system is far from stable.

But the Zimovs are learning and refining the concept, and herds have been constantly growing over the past years. To raise awareness — and the money needed to keep the experiment going — they recently established a second, 300-hectare park near Moscow, where the less harsh climate is more amenable to supporting large numbers of herbivores. And in the not-too-distant future, when and if the technology allows it, the mighty, tusked force of the woolly mammoth might come to their aid.

A few years ago, the Zimovs joined forces with a team of geneticists at Harvard who are attempting to bring back to life the ice-age icon, or at least a hybridized version of it, through an ambitious feat of genetic engineering. The notion — also known as de-extinction — has flickered between reality and science fiction for several decades, tickling our imagination with countless books and movies. For most of that time, however, the science of de-extinction has fallen far behind the fantasy.

But scientists now finally do appear to be on the brink of achieving the feat. Thanks to advances in genetic technology and the advent of CRISPR-Cas9, a gene-editing tool that allows for quick and cheap splicing of genomes, they can place individual genes that code for physical and behavioral features into the genome of existing creatures.

That’s the method being used by Harvard geneticist George Church and his team at the Woolly Mammoth Project. Using CRISPR, they are programming a number of mammoth traits, such as cold-resistant blood, subcutaneous fat, and a luxurious fur coat, into the DNA from the Asian elephant, the mammoth’s closest living relative.

Church’s team has successfully tweaked about 50 genes so far, and he says they might almost be ready to assemble the edited cells into a hybrid embryo and see if it survives to term in an artificial womb. If scientists can get past this hurdle, Church thinks the first mammoth-like elephant could roam the Pleistocene Park in a decade.

The attempt to revive the woolly mammoth — one of several efforts aiming to use genetics to restore lost species — raises big questions about the implications of reintroducing extinct life into the world and whether it can be ethically acceptable for humans to do so.

One concern is that introducing lost species into the modern environment could severely disrupt natural ecosystems as they are today.

While this might not be the case of woolly mammoths, studies show that, depending on a number of factors, the presence of animals in an ecosystem can have dramatic impacts on landscape — even pivoting them from being carbon sinks to net emitters.

A second concern relates to the welfare of the cloned animal itself. Joe Bennet, an assistant professor and conservation researcher at Carleton University in Ontario, Canada, says: “Mammoths are cognitively sophisticated animals. If one is brought to life and was subject to, say, disturbing conditions, or unable to learn to have mammoth behavior, or mammoth culture, this could be distressing and extremely painful for the creature.”

Although promoters of de-extinction have framed it as a useful conservation solution, critics have also argued that pursuing it will do little to address the current crisis of global biodiversity decline and habitat loss.

Ronald Sandler, director of the Ethics Institute at Northeastern University in Boston, Massachusetts, agrees: “I think de-extinction fails as both conservation ethic and conservation strategy since it does nothing to address the drivers of the problem, it has a long-time frame, a lot of barriers to overcome, and its conservation value is highly uncertain,” he says.

The Zimovs, on their part, do not seem too bothered by such considerations. When I asked Nikita whether he believed that his willingness to intervene, dramatically, in nature amounted to playing God, he scoffed at the notion. “I don’t see any of that,” he says. “All I want to do is bring animals back to where they used to be and stop permafrost thawing.”

His father Sergey takes a more philosophical, though no less unfazed stance. “I was raised as an atheist. Playing God doesn’t trouble me after all,” he says. “I just hope to be good at it.”

Update: Due to an editing error, a previous version of this article misattributed quotes to Ben Minteer, an environmental ethicist at Arizona State University contacted by the reporter of this story. These quotes were published in error and have been removed from the story.

Freelance writer. My works appeared in National Geographic, The Economist, The Guardian, Al Jazeera, Nature, Smithsonian, Reuters, among many others.

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