Animals and Insects

Animals Can Be Declared De-Extinct ... But How Does That Work?

Scientists have discovered how to breathe life back into species that were once considered extinct — but doing that could have consequences.

Animals Can Be Declared De-Extinct ... But How Does That Work?
Getty Images / Peter Macdiarmid

For some lost speciesde-extinction could offer a literal revival.

It's estimated 20 percent of species on Earth currently face extinction, and by the end of the century, that number could up to 50 percent.

There are several ways to resurrect a species. Scientists can use back-breeding, a technique that involves breeding animals to develop the genetic traits in their extinct relatives.

A Galápagos tortoise faces the camera.

A Galápagos Tortoise Species Thought To Be Extinct Has Resurfaced

A species of Galápagos Tortoise that lives on the islands was thought to be extinct — but scientists now have evidence it might have survived.


Other researchers might opt for cloning — taking a cell nucleus from an extinct species and putting it into a related host — or just manipulating an existing animal's genes.

But because de-extinction efforts are relatively new, there's a lot of disagreement over if it's a good idea.