In North America, a small carnivore lives: the black-footed ferret, which is small and weighs only about 0.8-1 kg, but is a ferocious carnivore, eating an average of about 100 marmots per year.
The survival of black-footed ferrets is inseparable from groundhogs, which not only feed on them, but also occupy their nests. However, because marmots compete with livestock for pasture, and are one of the source organisms, they are prone to potentially high pathogens, so in the last century farmers and governments in the Americas began to release poisonous feeding to eliminate marmots.
The decline in the population of marmots has caused the black-footed ferrets to have a reduced food source, so that their populations have been declining. This, combined with habitat loss and the spread of infectious diseases, led to the collapse of the otherwise unpredicted population of black-footed ferrets, so much so that in the last century Canada and the United States declared black-footed ferrets extinct.
But surprisingly, more than 100 black-footed ferrets were found in the United States about 10 years after they were declared extinct, but only due to infectious diseases and other reasons, only 18 individuals were eventually captured and bred in artificial environments.
Fortunately, thanks to the efforts of the staff, the number of black-footed ferrets has rebounded. But another conundrum that has always threatened the survival of black-footed ferrets is the loss of genetic diversity.
We know that when a population decreases, the genetic diversity within its population also decreases, and even if they can reproduce in larger quantities, the inbreeding coefficient of these offspring is higher, so that the genetic similarity is higher, and almost all black-footed ferrets are currently related. This means that despite the large number of populations, if there is an outbreak of infectious diseases within the population, etc., it may lead to the total annihilation of the entire population.
In order to protect them as much as possible, people will divide them into different places to survive, so that even if one population develops infectious diseases, another population of individuals survives, and the United States currently houses these black-footed ferrets in northeastern Montana, western South Dakota and southeastern Wyoming.
However, this approach has always been a palliative approach, not a cure, and the really effective approach is to maximize their genetic diversity. That is to say, if a wild individual can be found from the wild at this time, then the genetic diversity of the population can be enriched.
But scientists have never found these individuals in the wild. Fortunately, a research institute in the United States still retains the DNA of a black-footed ferret that died in 1988, and can be resurrected using cloning techniques.
<h1>Clone the black-footed ferret</h1>
In 1988 , the wild black-footed ferret Vera left no offspring that had survived the breeding period , so its genes were interrupted , and all black-footed ferrets today are not related to it.
In order to expand the genetic diversity of black-footed ferrets, scientists took eggs from the black-footed ferret's close relatives, domestic ferrets, and removed the nucleus of the egg, moved Vera's somatic nucleus into the denucleated egg cells, and through a series of techniques, the cells performed the function of germ cells, began to divide continuously, and formed fertilized eggs.
The scientists then moved the fertilized egg into a domestic ferret, where it gave birth to a clone, Elizabeth Ann.
The individual's genes are exactly the same as Vera's, and when it survives to adulthood, scientists can mate with existing black-footed ferrets, thereby enriching the genetic diversity of the black-footed ferret population and enhancing their environmental resistance.
<h1>Cloning endangered organisms</h1>
In fact, the black-footed ferret is not the first endangered creature cloned by scientists, and the Przewalski's wild horse has been successfully cloned before.
Successful cloning of endangered species requires several prerequisites, the first of which is to preserve the DNA of wild individuals, whether it is a black-footed ferret or a Przewalski's wild horse, scientists have preserved the DNA of a group of wild individuals in the last century, although these individuals have died and have not left any offspring, but scientists believe that when the time is ripe, these cells can help them "regenerate". The reason mammoths are difficult to clone is that they have been extinct for so long, living somatic cells are difficult to preserve, and DNA degrades in natural environments, so cloning is more difficult than expected.
The second is to be able to find "surrogate mothers", mammoths are large, it is difficult to have organisms to help them "surrogate", and elephants suitable for mammoths "surrogacy" are also endangered organisms, so this activity has not been implemented. Cloning of black-footed ferrets is successful because their close relatives, domestic ferrets, can provide "surrogacy services".
<h1>summary</h1>
Although the number of individuals of some organisms has recovered today, they are still in danger of extinction because their genetic diversity is not rich enough to withstand external environmental changes. In order to protect wild animals and improve their ability to resist risk, scientists have begun to apply cloning technology to it, and it is believed that more and more species will be able to truly get rid of the risk of extinction in the future.