Cloning isn’t just for celebrity pets like Tom Brady’s dog

And some animal welfare groups are opposed to the practice of pet cloning. People for the Ethical Treatment of Animals (PETA) described it as “a horror show,” and the UK’s Royal Society for the Prevention of Cruelty to Animals (RSPCA) says that “there is no justification for cloning animals for such trivial purposes.”

But there are other uses for cloning technology that are arguably less trivial. Wisely has long been interested in diversifying the gene pool of the critically endangered black-footed ferret, for example.

Today, there are around 10,000 black-footed ferrets that have been captively bred from only seven individuals, says Wisely. That level of inbreeding isn’t good for any species—it tends to leave organisms at risk of poor health. They are less able to reproduce or adapt to changes in their environment.

Wisely and her colleagues had access to frozen tissue samples taken from two other ferrets. Along with colleagues at not-for-profit Revive and Restore, the team created clones of those two individuals. The first clone, Elizabeth Ann, was born in 2020. Since then, other clones have been born, and the team has started breeding the cloned animals with the descendants of the other seven ferrets, says Wisely.

The same approach has been used to clone the endangered Przewalski’s horse, using decades-old tissue samples stored by the San Diego Zoo. It’s too soon to predict the impact of these efforts. Researchers are still evaluating the cloned ferrets and their offspring to see if they behave like typical animals and could survive in the wild.

Even this practice is not without its critics. Some have pointed out that cloning alone will not save any species. After all, it doesn’t address the habitat loss or human-wildlife conflict that is responsible for the endangerment of these animals in the first place. And there will always be detractors who accuse people who clone animals of “playing God.”

For all her involvement in cloning endangered ferrets, Wisely tells me she would not consider cloning her own pets. She currently has three rescue dogs, a rescue cat, and “geriatric chickens.” “I love them all dearly,” she says. “But there are a lot of rescue animals out there that need homes.”

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