Scientists Genetically Modify Wolves to Resemble the Extinct Dire Wolf

In a secure, undisclosed location in the United States, three genetically engineered wolf pups are roaming, sleeping, and howling — and they might be the closest living resemblance to the long-extinct dire wolf, according to biotech company Colossal Biosciences.

These pups, aged between three and six months, already show striking features: long white fur, powerful jaws, and an impressive weight of around 80 pounds, with projections to reach up to 140 pounds once fully grown. These physical traits echo those of the dire wolf, a species that vanished over 10,000 years ago and was significantly larger than the modern gray wolf.

However, independent scientists caution that this doesn’t mean dire wolves are returning to North America’s ecosystems anytime soon.

“You can’t truly bring back an extinct species — all you can do is recreate something that looks a bit like it,” said Vincent Lynch, a biologist at the University at Buffalo, who is not involved with the project.

To identify the traits of the dire wolf, Colossal researchers analyzed ancient DNA extracted from two fossil specimens — a 13,000-year-old tooth found in Ohio and a 72,000-year-old skull fragment discovered in Idaho. Using insights from these samples, scientists targeted 20 genetic sites for editing.

They began by extracting blood cells from a living gray wolf and used CRISPR gene-editing technology to modify its DNA. The altered genetic material was then inserted into dog egg cells. These were implanted into surrogate dogs, and after a 62-day gestation, the modified wolf pups were born.

Colossal has launched similar de-extinction-style efforts, including attempts to recreate animals resembling the woolly mammoth and the dodo by editing the genes of existing species.

Despite their appearance, these engineered wolves are unlikely to fully adopt the behaviors or ecological roles of dire wolves. “They won’t learn how to take down large prey like giant elk or deer,” noted Matt James, head of animal care at Colossal, adding that behavior is often passed down by observing parents — something these animals won’t experience.

In a separate but related project, Colossal also announced the successful cloning of four red wolves using blood from wild individuals in the critically endangered southeastern U.S. population. The goal is to enhance the genetic diversity of captive red wolves used in conservation breeding programs.

While this cloning approach is seen as less invasive than older methods, it still requires sedating wild wolves to collect blood, which remains a complex and sensitive task, said Christopher Preston, a wildlife ethicist at the University of Montana.

Colossal’s CEO, Ben Lamm, revealed that the team recently met with U.S. Interior Department officials to discuss their work. U.S. Secretary of the Interior Doug Burgum praised the project on X (formerly Twitter), calling it a “thrilling new era of scientific wonder.” But some scientists remain skeptical about the ecological impact.

“The world has changed. Even if you recreate something that looks like a dire wolf, it can’t step back into the same role it once had in an ecosystem that no longer exists,” said Lynch.