After their breakthrough in engineering “woolly mammoth mice,” Colossal Biosciences has announced that they have successfully brought back dire wolves — an Ice Age predator that went extinct roughly 13,000 years ago.
Colossal’s research began after scientists recovered dire wolf DNA from well-preserved fossils, including a 13,000-year-old tooth found in Ohio and a 72,000-year-old inner ear bone from Idaho. With the genetic material in hand, the team compared it to the genomes of modern canids — such as wolves and foxes — to identify genetic variants linked to distinct dire wolf traits like white, bushy coats and strong jaws. While previous research pointed to jackals as the dire wolf’s closest living relative, Colossal’s analysis suggests that it’s actually gray wolves, which share 99.5 percent of their DNA with them.
Using CRISPR technology, researchers then identified and modified 20 key genes in gray wolf cells to replicate traits of their extinct relatives, including size, coat density, and mane growth.
The edited DNA was transformed into embryos and implanted into surrogate dog mothers. Three pups were born as a result: in Oct. 2024, two males named Romulus and Remus, and in Jan. 2025, a female named Khaleesi, a nod to the TV show Game of Thrones, which popularized the species.
The pups exhibit the distinct features of dire wolves, including larger frames, thick pale fur, and bushy tails. They are currently being raised in a secure, undisclosed facility in the northern U.S., where scientists will care for them and monitor their development. The trio will most likely remain in captivity for the rest of their lives, and as of now, there are no plans to breed the wolves.
Public reaction has been mixed. While some herald the scientific ingenuity behind the project, others express concern over the ethical and ecological implications of “de-extinction.”
Some critics question whether these animals can be considered dire wolves. While each pup has some of the traits of a dire wolf, this does not necessarily make them one. Rather, they are more like gray wolves modified to resemble their relatives. Moreover, without dire wolf parents to teach natural behaviors or an Ice Age ecosystem to inhabit, they are, biologically and ecologically, a novel hybrid.
Additionally, ecologists warn that even if released, these creatures would be functionally alien in today’s world. The mammals they once hunted — ground sloths, mastodons, and ancient bison — are long gone. Their role as apex predators could disrupt modern food chains or compete with endangered gray wolves. Colossal argues the research could aid endangered species, but skeptics counter that funding and effort might be better spent protecting existing wildlife facing extinction.
The scientific community is awaiting publication from Colossal Biosciences to assess their controversial claims and methodology. The Colossal team released a preprint paper on April 11 detailing their findings, but peer-review may take several months.
Leave a Reply