It belongs in sci-fi — but it actually exists in reality.

On the Svalbard island of Spitsbergen, one of the remotest places on Earth, mostly covered with ice and hundreds of miles from mainland Norway to the south and Greenland to the west, a doorway leads into the side of a frozen mountain. Inside, past a long hallway and through an icy chamber, is a minus-18-degrees-Celsius (0 degrees Fahrenheit) room, containing nothing but rows upon rows of containers.

Here’s where the sci-fi ends: There are no aliens here, and no clones. Instead, the containers are full of humble seeds, frozen and preserved — hopefully forever (or long enough, anyway). Ultimately, there’s enough room to store 2.25 billion of them.

Scientifically inclined — and worried — humans built this. It’s the pinnacle of an ancient quest to store seeds so as to preserve agricultural diversity and give a backstop against any crop disaster.

Indeed, the Svalbard Global Seed Vault is described by the Crop Trust, which helps to fund its operations, as the “ultimate insurance policy for the world’s food supply, offering options for future generations to overcome the challenges of climate change and population growth.” The vault was created by the government of Norway and serves as a backup of a backup: Many countries have seed repositories or “genebanks” that exist to provide a reserve in case of some kind of crop catastrophe. Svalbard, in turn, retains copies of these repositories’ contents — in case something happens to them, too.

Why is the world preserving so many seeds? The Crop Trust gives no less than six reasons, many of which are fundamentally environmental. Much of it comes down to this — when conditions change, we need to be able to breed new plant varieties to create crop strains that can, say, thrive in a warmer world. Or a drier one. Or a wetter one. Whatever happens.

To do this you need, as a baseline, access to as much genetic diversity as possible — so that scientists can start breeding new plants right away if it ever comes to that.

These seed repositories also contain a vital piece of human history. Ever since the dawn of agriculture, plants that we cultivate have been evolving, as we have pushed them to develop new traits through breeding. So seed vaults and repositories also preserve a long history of past human-plant interactions that pushed genomes to change in the way we wanted them to.

The hope is that we’ll never need these seeds. But then you can see how, despite the seemingly steady soar of civilization, humanity might someday find itself in need of a parachute.

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