HOW TO SAVE THE NORTHERN WHITE RHINO

The last three northern white rhinos are unable to breed naturally. A Berlin-based team hopes to de-extinct this animal using IVF and advanced stem cell biology

PLAN A: NATURAL EGGS AND SPERM

PLAN B: ARTIFICIAL EGGS AND SPERM

Skin cells from 12 di erent northern white rhinos have been stored

Researchers will collect eggs from the female, Najin, and her daughter Fatu

Sperm from Sudan, the last male northern white rhino, along with four other males, has been collected and frozen

Add in a handful of extra genes

Eggs

IVF

Sperm

Stem cells

Embryo

Embryo is transferred into the uterus of a female southern white rhino, the northern white rhino’s closest living relative

A healthy de-extinct northern white rhino is born

WHAT WE STILL DON’T KNOW

I C S

A C U T E G R A P H

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I O N

I L L U S T R AT

1 HOW CLONING WORKS Although we’ve been cloning animals for years, we still don’t understand how it actually works. During the process, DNA inside an adult cell is somehow reprogrammed to a more youthful state, so that it can drive embryonic development. It’s like restoring the factory se ing on your phone, but no one knows exactly how it happens or how to fully control it. Crack that, and scientists stand a be er chance of creating healthy, viable animals.

2 HOW RESURRECTED ANIMALS WILL BE PROTECTED To qualif y for legal protec t ion, an organism must be listed as endangered, but for that, the animal must be living in the wild. The first few generations of any newly resurrected species would be kept in captivity while researchers checked their health, so during this time their legal status would be uncertain. Without protection, the animals could be threatened by poaching or habitat loss.

3 HOW DE-EXTINCT ANIMALS WILL FARE IN THE WILD When it comes to releasing the animals, all we can do is study their previous ecology, and send them into the most suitable environment available. We’ll then need to monitor them carefully: it’s vital to know why a species went extinct first time round, to make sure it doesn’t happen again. With each successive re-wilding a empt, we’ll learn more about maximising the animals’ chances of survival.

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