On April 7, 2025, Colossal Biosciences announced the birth of three pups named Romulus, Remus, and Khaleesi. They were presented as the first living “dire wolves” in over 10,000 years. But the central question remains: are they truly dire wolves?

According to the company, they were developed via genetic engineering to recover the phenotypic traits of the extinct species. However, the scientific community is still debating the validity of this claim.

The Genetic Engineering Behind the New Pups

The project began with analyzing two dire wolf fossils: a tooth roughly 13,000 years old and an inner-ear bone dated to about 72,000 years ago. Scientists extracted DNA fragments from these specimens and compared them to the genome of modern gray wolves.

This comparison identified around 20 genes linked to traits such as coat color (including the CORIN gene), body size, and skull morphology. After editing these genes, the modified cell nuclei were inserted into dog eggs, carrying the embryos to term via cesarean section. Romulus, Remus, and Khaleesi are now five months old.

Are They Really Dire Wolves?

Experts remain divided. Paleoecologist Jacquelyn Gill argues that without a complete genome of the extinct species, it’s impossible to confirm that these pups are real dire wolves. To her, they are gray wolves with some traits inspired by ancient records.

On the other hand, Colossal’s chief scientific officer, Beth Shapiro, contends that the project’s aim isn’t to clone an extinct animal but to restore its key characteristics. A new preprint seems to support this approach, suggesting that the genetic difference between dire and gray wolves may be smaller than previously thought.

Ethical Questions and Environmental Concerns

Despite the technological breakthrough, the experiment raises many concerns. Experts warn of the risk of public misunderstanding, as people may believe the species has been brought back to life. Furthermore, the environmental impacts of introducing these animals are still unknown, as are the welfare implications for the pups, as they live in isolation without interacting with a natural pack.

Some critics liken the scenario more to Jurassic Park fiction than to realistic conservation science.

Red Wolf Conservation: A More Urgent Application

Meanwhile, Colossal is working on cloning wolves using ancestral red wolf DNA. The red wolf is critically endangered in the United States, with fewer than 20 individuals left in the wild. These “ghost red wolves” aim to boost the genetic diversity of the remaining population.

For scientists like Heather Jay Huson, this type of intervention is far more justifiable and pressing than projects focused on recreating extinct species.

Where Are the Pups Now?

Romulus, Remus, and Khaleesi live on an 800-acre protected reserve under the care of a ten-member team. Their exact location has not been disclosed for security reasons. Currently, there are no plans for public display or breeding.

Researcher Adam Hartstone-Rose intends to study their bone structure and behavior in the future but expresses concern over their social isolation from a natural pack context.

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