Reviving Extinct Animals: a Tool for Fighting Global Warming?

Candice Gaukel Andrews April 16, 2013 22

Long-gone animals performed vital services in their ecosystems, which benefit when they return, such as these aspens in Yellowstone National Park. ©Henry H. Holdsworth

When National Geographic magazine came out with their cover story on de-extinction in April 2013, it set off quite a controversy. Now that we are on the scientific brink of being able to bring back long-gone species, proponents and critics are hotly debating whether we should.

An intriguing side issue to this discussion relates to our native landscapes and the biodiversity they provide—and how quickly we’re losing them. We know that extirpated animals performed vital services in their ecosystems, which benefit when they return.

Could de-extinction, then, achieve a similar result?

The wolves of Yellowstone National Park

Without a predator to evade, there was no reason for elk to seek thick cover. ©Henry H. Holdsworth

Landscape restoration is defined as the attempt to reverse human impact by returning an ecosystem or habitat to an earlier state; or as some call it, its “predisturbance situation.” Restoration means trying to copy a specific historical structure; in a sense, turning back the environmental clock. Some say restoration is more aptly characterized as making the environmental clock tick again. Standard examples of such efforts include eliminating nonnative, invasive animal or plant species and reintroducing formerly native species.

The wolves of Yellowstone are probably one of the most well-known examples of reintroducing a native species. During the wolves’ 70-year absence from the park as a result of being killed off by humans, elk were free to roam, reproduce and feed on the region’s small aspen shoots. Starting in 1995 when the wolves were reintroduced, the elk’s fear and reduced population improved the aspens’—a tree species in decline all over the West—chances for survival. From the 1920s to the early 1990s, when wolf packs were absent in Yellowstone, no new aspen trees that hadn’t suffered from animal browsing were found. The first time that significant aspen growth was documented was after the wolves came back. In the past few decades, a large number of aspen trees have reached heights of more than seven feet, key for long-term survival because it places the crowns high enough to keep them safe from elk.

Aspens aren’t the only landscape beneficiaries of the wolves’ return. In the absence of their predators, elk not only chewed on trees but browsed heavily in the open flats along rivers and wetlands. Without a predator to evade, there was no reason for them to seek thicker cover. Since the Yellowstone wolves have come back, elk spend more time in the safety of dense vegetation or on the move. As a result, riparian areas that had been suppressed by decades of overbrowsing are regenerating, improving habitat for species such as beavers and songbirds. Beavers, which create wetlands with their dams, have improved water quality in streams by trapping sediment, replenishing groundwater and cooling water.

According to the Wyoming chapter of the Sierra Club, other species that rely on healthy riparian habitats and benefit from the presence of wolves in Yellowstone National Park include:

  • amphibians,
  • insects,
  • moose,
  • small mammals (muskrats and other rodents),
  • songbirds (warblers, wrens, and thrushes),
  • waterfowl (ducks, geese, trumpeter swans) and
  • Yellowstone cutthroat trout and other native fish.

The woolly mammoths of Siberia

So, we know that returning extirpated wildlife can restore native landscapes. But now that we’re capable of bringing back long-extinct species, landscape restoration by the use of wildlife takes on a new twist.

Beavers have benefited by the wolves’ return; and, in turn, have improved the water quality of streams. ©Henry H. Holdsworth

Twelve thousand years ago, northern Siberia was home to woolly mammoths and other big, grazing mammals. Back then, the landscape was not moss-dominated tundra as it is today but grassland.

Sergey Zimov, a Russian ecologist and director of the Northeast Science Station in Chersky, believes that this was no coincidence; the numerous herbivores maintained the grassland by breaking up the soil and fertilizing it with their manure. Once they disappeared, moss took over and transformed the grassy steppes into less productive tundra.

In recent years, Zimov has tried to turn back time on the tundra by bringing European bison, musk ox, Yakutian horses and other big mammals to a region of Siberia he calls Pleistocene Park. His theory is that by filling the vast, Russian Arctic with grass-eating animals, we can slow global warming. Today, climate change is being felt most sharply in the Arctic, where temperatures are warming faster than anywhere else on the planet. Zimov states that his herbivores will keep wild grass short and healthy, causing it to send up fresh shoots through the summer and fall. In winter, the animals will trample and flatten the snow that otherwise would insulate the ground from the cold air. That helps prevent the permafrost from thawing and releasing powerful greenhouse gases. Grass also reflects more sunlight than forests, a further impediment to global warming. Climate scientists and environmentalists are watching Zimov’s Pleistocene Park project closely.

Skeptics say, however, that it will take millions of animals to change the landscape of Siberia and effectively seal the permafrost. But Zimov says that left alone, big grazers such as bison, caribou and musk ox multiply quickly.

He believes the next step—with the help of de-extinction scientists—may be to bring in the woolly mammoths.

Do you think that landscape restoration is a compelling reason to support de-extinction?

Here’s to finding your true places and natural habitats,



  1. Ratikanta Maiti April 21, 2013 at 8:36 am - Reply

    Reviving extinct plants is also a tool for fighting global warming.

  2. Elias Sadalla Filho April 21, 2013 at 8:35 am - Reply

    That’s a very interesting issue!

  3. Casey Eckert April 20, 2013 at 11:43 am - Reply

    I agree wholeheartedly, Michael; the environment evolves but rather than “go back”, I’d much rather we spend our time and resources on solving present and potentially future concerns.

  4. Michael Horak April 19, 2013 at 5:13 am - Reply

    While bringing back extinct organsims sounds intriguing, I suspect more hubris is involved than actual thought to consequence or result. The organisms are extinct for a reason which we may or may not have a clear grasp of. Just because we may be able to do something does not mean we should necessarily spend the time and resources on such a project. What current issues and needs could be addressed with such techniques and capabilities?

  5. Richard H. McNutt April 19, 2013 at 5:12 am - Reply

    I would feel better leaving Darwin alone and taking care of what we have here now in balance. Get rid of stress and suffering of all who live here now.

  6. Roger Simpson April 19, 2013 at 5:10 am - Reply

    I was driving home from work last night looking across the cleared agricultural landscape and musing that most of the native animals in this region had evolved to live in the heavily wooded wet forests that existed across the region. The local native fauna is therefore small and disposed to a cool and sheltered albeit wet environment. The forests were so thick and dense that early european explorers clamied they could smell them 90 miles out to sea. Today the landscape is much changed having been cleared of most of the trees over 100 years ago. The deep rich soils laid down within these forests is slowly being transported down the catchment with each rain event. It made me wonder how successful is the remaining native fauna in this now windswept uncovered environment. Some of the burrowers like wombats seem to be doing ok, but it is rare to see koalas, reptiles, wallabies, antychinus etc… The landscape no longer supports their former numbers. Many of the bird species now feed heavily on roadside fruit trees that have developed from distributed apple cores etc from car windows. They know exactly when the fruit is at its best and feast heavily.

    Before we consider de-extinction programs we need to address the health of supporting ecosystems.

  7. Ron Paul April 19, 2013 at 5:09 am - Reply

    Yes we have to bring back long gone species because their interaction on the globe means alot to human nature..

  8. Jude Price April 19, 2013 at 5:08 am - Reply

    Stupid science – what is an extinct animal? By default even if an extinct animal could be born, they would have to be laboratory raised – an animal is not just his or her shape and appearance, an animal is a whole being, shaped by genetics, but their lives are lived in relationship with their mothers, their environment, other species. A ‘reproduction’ is not the animal. one could argue the “last” of anyone in a zoo is not a representative of their species in actuality – because of this same view. They are a facsimile. We have animals suffering in their environments now – with human encroachment and the resultant HWC, poaching, invasive species of plants and animals. We have intense human “management’ and still this is androcentric – The money spent nowhere near enough to restore landscape’ on the scale required for biocentric health and species protection. I think it is a waste of money on one hand and immoral on the other hand to bring “laboratory” animals into a world where they would be “sensations” , studied, live and die in isolation.

  9. Frankie Laney April 18, 2013 at 10:06 am - Reply

    A very evocative article. Right now my mind is trying to process all the potentials.

  10. Nathan O. Okia April 17, 2013 at 1:37 pm - Reply

    No, landscape is not the only raison d’etre. Personally, I like all those creatures to come back and live with us. Imagine a pet mammoth or dinosaur! These animals died from extraneous circumstances. They deserve to live. We might even benefit from their enormous sizes; plenty of protein to feed the masses!

  11. John Gbondo April 17, 2013 at 10:47 am - Reply

    This is interesting. Restoring landscape by using wildlife. This is the evidence of the basic uninterrupted ecosystem system services. Every memeber of the ecosystem is important for a balanced natural habitat.

    This practice is a viable natural initiative that will restore our ecosystems with time if we keep humans in check.

    I know Extinct species with no known relative is gone forever. There is need for a clear definition of our terms with regards extinction.

  12. James "Jim" O'Donnell April 17, 2013 at 10:45 am - Reply

    fascinating and thought-provoking. Thanks for this.

  13. sinnadurai sripadmanaban April 17, 2013 at 10:44 am - Reply

    When grazing lands and forests are dwindling new/older/extinct species won’t find enough food.

  14. Aaron Woodruff April 17, 2013 at 9:16 am - Reply

    As an ecologist I have no doubt that reintroducing species back into their former range would enrich the biodiversity and restore balance. My only concern would be the current state of the world and the rate of habitat loss. If this worsens it may be difficult to maintain self-sustaining populations. Before reviving any given species one would first have to know it’s preferred habitat, food preferences, why it became extinct in the first place, which animals hunted it, and its social structure. One should also consider potential human conflict and think of ways to benefit from these animals. In the case of the Woolly Mammoths, we know that it was a social, nomadic grazer that lived in arid open grasslands. The most suitable habitat for it in North America would be found in the Great Plains states and provinces. However, farmers and ranchers in this region have a difficult enough time accepting Gray Wolves and Plains Bison, so one can only imagine they may respond to a herd of elephants periodically passing through their property! A possible solution would be to establish an ecotourism industry similar to that of Africa. Reviving a large keystone herbivore like a mammoth is a good first steppe. Their presence would increase soil nutrients and improve plant diversity. Next I would reestablish the camel, horse, bison, and caribou herds that once coexisted with them. Their presence would balance out the the populations of smaller herbivores and provide a wider menu for existing predators. Finally, I would enrich the predator community by reintroducing Lions and Jaguars, thus keeping these large herbivores in check. (Forgive the long comment but this is something I’m passionate about) I could go on to type up an extensive paper about my research in this area, but to summarize I believe that there are many different factors to consider before undertaking such a project and the animals needs must be understood and met.

  15. Hans Friederich April 17, 2013 at 9:14 am - Reply

    Ecosystem restoration is not a reason to stop nature conservation!
    But – bringing back species from the death? A truly though-provoking idea. If it is possible, I cannot see why not.

    Could we take the same idea to producing ivory and rhino-horn? If we can mass-produce the product, the demand will diminish and the market will collapse.

  16. Merle Pierce April 17, 2013 at 9:11 am - Reply

    every species has its day, whose to say change isn’t good? Just a thought!

  17. Sarah April 17, 2013 at 6:24 am - Reply

    While I applaud the return of habitats and all efforts to conserve them, I do think that bringing back a truly extinct (not just extinct in the wild but alive in captivity) species is more complex than just bringing back its genetic code. An animal is more than the sum of its genes. Who will raise these animals to know what they are and pass on the important learned information that they may need in order to find mates, food, etc? This is especially important with species that have many time-sensitive learned behaviors (such as species-specific songs with birds) or socially complex animals (such as primate troops). If we cannot properly teach those behaviors, are we really bringing back a species or just a visually convincing facsimile?

  18. Bob Gettman April 16, 2013 at 5:48 pm - Reply

    Thank you for an interesting and thought-provoking discussion, Candice. Always much appreciated!!

  19. Carlos Reyes April 16, 2013 at 5:47 pm - Reply

    Interesting concept, I have seen TED talks on the possibilities animals bring to the reversal of desertification… wouldn’t want a jurassic park though 🙂

  20. alloporus April 16, 2013 at 4:37 pm - Reply

    Surely ‘destinction’ would just let the bulk of us off the hook. We can extinct away in the knowledge that we can always engineer the lost species back to life.

    And I bet there is not a plan to reinstate all the lost insects, invertebrates, fungi and microbes that do all the really important work in ecosystems.

  21. Bruce Bunderson April 16, 2013 at 10:40 am - Reply

    I am fully supportive of reintroduction of populations of animals native to an area. Anyone who thinks humans can improve on nature’s “design” by eradicating animals or plants indigenous to an area are deluded. The issue of the systematic slaughter of wolves is a particularly sensitive one to me. They are not blood-thirsty murderers, they are apex predators, and as such serve vital roles in maintaining healthy ecosystems. Period.

  22. Kathryn April 16, 2013 at 9:56 am - Reply

    This is not as strange as it seems. Zimov is right about rates of restoration of large grazers. They come back quickly.

    Establish them in multiple, scattered, protected refuges and let those grow past their boundaries without hunting/culling etc.

    Answer to skeptics? Better to go for it now … time is short. Grasslands are critical.

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