Is it Possible to Bring Back Extinct Animal Species?

Is it Possible to Bring Back Extinct Animal Species?

View a higher resolution version of this infographic.

Humanity has been tinkering with natural life for thousands of years.

We’ve become remarkably good at it, too—to date, we’ve modified bacteria to produce drugs, created crops with built-in pesticides, and even made a glow-in-the-dark dog.

However, despite our many achievements in the realm of genetic engineering, one thing we’re still working on is bringing extinct animals back to life.

But scientists are working on it. In fact, there’s a whole field of biology that’s focused on reviving extinct species.

This graphic provides a brief introduction to the fascinating field of science known as resurrection biology—or de-extinction.

The Benefits of De-Extinction

First thing’s first—what is the point of bringing back extinct animals?

There are a number of research benefits that come with de-extinction. For instance, some scientists believe studying previously extinct animals and looking at how they function could help fill some gaps in our current theories around evolution.

De-extinction could also have a beneficial impact on the environment. That’s because when an animal goes extinct, its absence has a ripple effect on all the flora and fauna involved in that animal’s food web.

Because of this, reintroducing previously extinct species back into their old ecosystems could help rebalance and restore off-kilter environments.

There’s even a possibility that de-extinction could slow down global warming. Scientist Sergey Zimov believes that, if we were to reintroduce an animal that’s similar to the woolly mammoth back to the tundra, it could help repopulate the area, regrow ancient plains, and possibly slow the melting of the ice caps.

How Does it Work?

The key element that’s needed to re-create a species is its DNA.

Unfortunately, DNA slowly degrades, and once it’s gone completely, there’s no way to recover it. Researchers believe DNA has a half-life of 521 years, so after 6.8 million years, it’s believed to be completely gone.

That’s why species like dinosaurs have virtually no chance of de-extinction. However, many organisms that went extinct more recently, like the dodo, could have a chance of conservation.

When it comes to de-extinction, there are three main techniques:

① Cloning

This is the only way to create an exact DNA replica of something.

However, a complete genome is needed for this, so this form of genetic rescue is most effective with recently-lost species, or species that are nearing extinction.

② Genome Editing

Genome editing is the manipulation of DNA to mimic extinct DNA.

There are several ways to do this, but in general, the process involves researchers manipulating the genomes of living species to make a new species that closely resembles an extinct one.

Because it’s not an exact copy of the extinct species’ DNA, this method will create a hybrid species that only resembles the extinct animal.

③ Back-Breeding

A form of breeding where a distinguishing trait from an extinct species (a horn or a color pattern) is bred back into living populations.

This requires the trait to still exist in some frequency in similar species, and the trait is selectively bred back into popularity.

Like genome editing, this method does not resurrect an extinct species, but resurrects the DNA and genetic diversity that gave the extinct species a distinguishing trait.

Is Bringing Back Extinct Animal Species Really Worth it?

While there’s a ton of buzz and potential around the idea of bringing back extinct animal species, there are a few critics that believe our efforts would be better spent on other things.

Research on the economics of de-extinction found that the money would go farther if it was invested into conservation programs for living species—approximately two to eight times more species could be saved if invested in existing conversation programs.

In an article in Science, Joseph Bennett, a biologist at Carleton University in Ottawa, said “if [a] billionaire is only interested in bringing back a species from the dead, power to him or her.”

Bennett added, “however, if that billionaire is couching it in terms of it being a biodiversity conservation, then that’s disingenuous. There are plenty of species out there on the verge of extinction now that could be saved with the same resources.”