When an animal becomes endangered, and especially critically endangered, it faces a very difficult series of challenges if it is to survive. One of the challenges that many people don’t think of is that of genetic diversity.

If there are only a small number of a given species, that means that the breeding population, and therefore the genetic diversity, is very limited. That is the situation that the black-footed ferret was facing after its population was threatened in the wild and even in zoos.

The Smithsonian National Zoo and Conservation Biology Institute began a breeding program, but given the number of these ferrets available, the risk of genetic defects was significant. To overcome this problem, they found some ferret tissues that were harvested in 1988.

The San Diego Zoo Wildlife Alliance’s Frozen Zoo program has long been taking and preserving tissues of animals, and especially animals that are at risk.

Using this tissue, the team was able to make a clone of the animal successfully. From there, they had the cloned female mate with a naturally born male.

A short time later, it was confirmed that the cloned female was pregnant. It then gave birth to two healthy kits (baby ferrets). This is the first time that a cloned animal was able to successfully have babies, which is a major milestone.

In a statement, Ryan Phelan of the Revive & Restore group said:

“This project represents a historic milestone in conservation history. For the first time, we can definitively say that cloning contributed meaningful genetic variation back into a breeding population. As these kits move forward in the breeding program, the impact of this work will multiply, building a more robust and resilient population over time.”

Assuming the kits mature normally, which they seem to be doing, they will help to dramatically expand the genetic diversity of the black-footed ferret population. The mother, named Antonia, had about three times more genetic diversity than the existing animals.

That diversity has now been passed down to the offspring, who will hopefully be able to further add it to the population over time.

There is no word on whether additional cloning will be done to further boost the population, but this is a major milestone in the conservation not only of the black-footed ferrets, but all endangered animals.

If you think that’s impressive, check out this story about a “goldmine” of lithium that was found in the U.S. that could completely change the EV battery game.