Did they really brought back dire-wolves back from extinction?

Science calls it "enocione," in English it has the more evocative name of "dire wolf" (which means "terrible wolf" or something similar), and Italian fans of Game of Thrones know it by the term coined by the Italian translator of the saga, Sergio Altieri, as "metalupi." They all refer to the same animal: a distant cousin of today's wolves, dogs, and jackals that went extinct about 10,000 years ago – a very strong animal, used to hunting the megafauna of its time, but in fact no larger than the modern gray wolf. Today, this species has been "de-extincted", meaning brought back to life through genetic manipulation in a much more complex way, but not enormously different from how the dinosaurs in Jurassic Park were revived. By using ancient DNA preserved for millennia, the scientists at the American company Colossal were able to decipher the genome of the dire wolf, rewriting the genetic code of the common gray wolf to match that of the extinct species. Using domestic dogs as surrogate mothers, they gave birth to three pups – Romulus, Remus, and their sister Khaleesi – over the course of three different births between the fall of 2024 and the winter of 2025. This is the first time a completely extinct genetic line has been brought back to life. These pups are not only a scientific milestone, as for the scientists behind the project they represent the rebirth of a species lost for over 10,000 years, but also a starting point for a company that dreams of saving the planet's biodiversity. Founded in 2021 and comprising over 130 scientists, the company aims to de-extinct other animals such as the mammoth, the dodo, and the Tasmanian tiger. And the first results are already making headlines: in March 2025, Colossal announced the creation of a "woolly mouse," a chimeric organism with long golden fur and the fat-metabolism of a mammoth.

How does "de-extinction" work?

As Time describes in a lengthy article, the return of the dire wolf was made possible by a less invasive procedure compared to traditional cloning. Although the common gray wolf shares about 19,000 genes with the dire wolf, researchers discovered that only 20 changes spread across 14 genes are needed to replicate its main physical and behavioral traits. These include a larger body, broader head and jaws, more muscular shoulders and legs, reinforced teeth, a white coat, and distinctive vocalizations such as howling and whining. The modifications were determined by analyzing the DNA extracted from two ancient fossil specimens provided by museums. After analyzing the genome, the researchers did not directly use fossil DNA: instead, they rewrote the desired genes into the DNA of modern gray wolf cells. Once the rewriting was completed, the modified nucleus was inserted into an ovum that had its own nucleus removed. A total of 45 modified ova were produced, which developed embryos in the lab. The embryos were then implanted in two surrogate females, both mixed-breed hounds, selected for their robustness and ability to carry a pregnancy with large pups.

In each mother, one embryo took hold and successfully completed the pregnancy. The first two pups, Romulus and Remus, were born on October 1, 2024, via planned cesarean section. A second birth, on January 30, 2025, brought Khaleesi into the world. All pregnancies were closely monitored with weekly ultrasounds and veterinary checkups at Colossal's animal care center. Immediately after birth, the pups were entrusted to the surrogate mother with the best maternal instincts, who began caring for and nursing them within hours, although after a few days, the scientists decided to feed them artificially, as the mother’s excessive attention was disrupting the pups' natural rhythms. Weaning occurred around eight weeks, after which the young wolves continued to grow healthy, fully displaying the characteristics of wild wolves. Today, the young wolves live in a protected ecological reserve of over 2,000 acres, with natural shelters, veterinary facilities, and a staff that assists them 24/7. Their diet is tailored to reflect what they would eat in the wild, although they do not hunt, and every aspect of their growth is closely monitored scientifically.

What is the purpose of "de-extinction"?

As Time explains, these projects are not just driven by scientific curiosity but also the desire to save species currently at risk of extinction. The experience gained with the mammoth could help strengthen modern elephants against climate change, and what is being learned from the dire wolf is already contributing to efforts to save the red wolf, a highly endangered American species. According to Beth Shapiro, the company’s scientific leader, humanity has now become an “evolutionary force” capable of deciding the fate of species and restoring what humans have damaged. The technique that made the dire wolf’s creation possible is finding applications, for example, in strengthening the red wolf population, now reduced to fewer than 20 individuals in the wild. To achieve this, Colossal has cloned four individuals using "ghost genes" discovered in hybrid populations of red wolves and coyotes along the Texas and Louisiana coast. These genes, though not physically expressed, retain the genetic legacy of the red wolf and can help overcome the so-called “genetic bottleneck” caused by poor diversity. But ethical and environmental concerns are not lacking: cloning can cause suffering to animals, genetic problems, miscarriages, and introducing new species into fragile ecosystems can produce unpredictable, even disastrous, effects.

As also illustrated by Time, the dire wolf became extinct following the extinction of the megafauna from its distant era, so not only is its presence today a sort of anomaly in today’s ecosystem, but the three pups born in these months will never have their own pack, and at the moment, there are no plans to release them, let them breed (even though more partners with the same genetic makeup would be needed to maintain the traits of the recreated species), or to let them live as real animals. There is also another potentially thorny issue regarding whether these animals are truly dire wolves: according to some publications, it is incorrect to say the species has been “de-extincted” when, in fact, a common gray wolf has been modified to resemble an extinct species that, incidentally, no one has ever truly seen apart from its bones. Discussing this with the New York Times, geneticist Adam Boyko referred to the three pups as “functional versions” of an extinct species, while New Scientist, which is more critical of the project, wrote: "Given that the gray wolf genome is around 2.4 billion base pairs long, there is still room for millions of base pairs of differences,” even though the modern animal and its prehistoric cousin share 99.5% of their DNA. A user on X gave a more humorous definition: “Unless you have access to like, a frozen embryo of an extinct animal, “de-extinction” is not something you can do. All you’re making is a transgenic animal with mods that satisfy human sensibilities. You did not bring an extinct species back to life. You just made living paleoart.” And this is to say that the new pups are versions, if you will, “photoshopped,” and thus represent hypotheses of a reconstruction of an extinct animal rather than true extinct animals. In short, more than a resurrection, it would be more accurate to talk about a careful simulation. At least until we see a mammoth walking in the northern United States again.