Should We Bring Back Extinct Species?

Imagine coming face-to-face with a woolly mammoth or a saber-toothed tiger. Those species have been extinct for thousands of years. But scientists say it may be possible to bring them back to life.

The process of resurrecting long-gone species, known as de-extinction, involves placing the DNA of an extinct animal into the cells of a living related species. (If you’re picturing a scene out of Jurassic World, there’s no need to worry: Experts say dinosaurs can’t be brought back from the dead, because their DNA is too old.)

Those in favor of reviving more-recently extinct animals say doing so could help repair damaged ecosystems. That’s because when one species dies out, many others are negatively affected.

But opponents of de-extinction say it isn’t worth the time—or money. Many habitats have changed so much that some long-gone species would have a hard time surviving in the modern world. Instead of concentrating on trying to bring back extinct species, critics say, scientists should focus on preventing animals from dying out in the first place.

Should we bring back extinct species? Two experts weigh in.

YES

Bringing back extinct species may sound like something out of Jurassic World. But de-extinction is real—and it can have several important benefits.

For one thing, de-extinction could play a key role in healing damaged ecosystems. That’s because it’s actually just an extension of good old-fashioned conservation work—the protection of existing animals and their environments. Conservationists have already had success returning living species to areas where they’ve died out. One example is the return of wolves to Yellowstone National Park. The animals’ extermination from the region a century ago led to environmental problems, such as the decline of certain trees.

De-extinction could help heal damaged ecosystems.

But just 20 years after scientists returned wolves to Yellowstone, the ecosystem is much healthier. That’s because by eating elk, which feed on trees, wolves give trees a chance to grow. The young trees attract beavers, which make dams that draw birds and amphibians. As a result of the wolves’ return, more species thrive in the park today. De-extinction could do the same in other places.

For example, more than 3 billion passenger pigeons once lived in North America’s forests. Their huge flocks helped create the woodlands that hundreds of plants and animals currently depend on. Since the pigeons’ extinction, diversity in forests has declined, leaving many species struggling. Bringing back passenger pigeons could help save some of them.

Of course, not every extinct animal would survive in modern times, and even fewer would serve important roles for conservation. That’s why we need to focus on bringing back species that could help other living things.

—Ben J. Novak
Lead Researcher, Revive & Restore

NO

By the time you go to bed tonight, a species that has lived on Earth for millions of years may be gone forever. Scientists believe that somewhere between 200 and 2,000 species of animals and plants become extinct every year. And that number could be even higher.

Although de-extinction has been called a way to reverse this horrible trend, the argument doesn’t hold up. For the millions of dollars it would cost to bring one species back from the dead and support it in the wild, we could save dozens of other species from going extinct in the first place.

Bringing back extinct species is expensive—and risky.

Because scientists have limited resources, a decision to do one thing is a decision not to do another. A decision to spend millions of dollars on bringing back one species is a decision to neglect others and possibly allow them to go extinct. We already have many animals—such as elephants, tigers, rhinos, and gorillas—that are in serious danger of disappearing. Why not focus on keeping them alive?

Bringing back extinct species is risky. In most cases, the animals’ habitats are gone or have been seriously altered. Mammoths, for example, went extinct after the Arctic began warming 10,000 years ago. It’s much warmer there now than it was then, and it’s getting hotter every year. If we were to bring back mammoths, we would probably need to spend a tremendous amount of money just to keep them alive. There’s also the risk that reintroducing long-extinct species would actually hurt the environment by disrupting existing local ecosystems.

The evidence is overwhelming: De-extinction isn’t a good investment for the planet. It may be interesting science, but it’s not conservation.

—Joseph Bennett
Assistant Professor of Biology, Carleton University