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To Preserve and Protect: How a "Frozen Zoo" Is Helping to Save Endangered Species

A video interview with one scientist storing the cells of 10,000 animals from 1,000 species.

Photo: Tammy Spratt / Copyright: San Diego Zoo

One driveway down from the main entrance to the San Diego Zoo is an even bigger collection of species, though one that the general public doesn’t get to see.

In the back corner of the bottom floor of the Institute for Conservation Research, in a room smaller than most studio apartments, sits the “Frozen Zoo.” It’s a collection of fat metal canisters filled with the cells of 10,000 individual animals of 1,000 different species. Many are endangered and a few are already extinct.

“It’s the biggest, most diverse, best characterized and most utilized collection of its kind,” said Dr. Oliver Ryder, director of genetics at the Institute for Conservation Research in San Diego, Calif., and effectively the head zookeeper for the genetic stockpile. “But it’s a small amount of biodiversity for the number of species that are potentially facing extinction.”

Indeed, at least 10,000 species go extinct each year, which is anywhere from 1,000 to 10,000 times greater than the “natural extinction rate,” according to WWF.

Ryder and his team use the cells to study genetic variation, monitor evolutionary changes between animal populations and trace hereditary links. But the broader hope is to help preserve endangered species by preserving cell lines that can be used to aid animals with critically low populations, through methods like cloning, converting stem cells into eggs or sperm, and implantation.

“This is a desperate strategy,” he said. “The way to save species is to save them in functional ecosystems and viable habitats.”

“All the same, there are species that are disappearing and there is no other way we can see to save them without exploring these technologies,” he said.

While it’s not the organization’s focus, there’s also the possibility that the cells could one day be used to help bring extinct species back to life. De-extinction of certain animals is already being seriously explored by groups like the Long Now Foundation and some prominent genetic researchers.

But Ryder wants to focus his energies on the many threatened species that can still be pulled back from the brink of annihilation. He sat down with Re/code earlier this week. For more of the interview (and to see some adorable animals), please watch the video below:

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