Colossal Biosciences, the company trying to genetically resurrect the wooly mammoth by 2028, rocked the world Monday by unveiling the return of a long-extinct species: The dire wolf.
Romulus and Remus, two white-haired pups, were born in October 2024 with the genetics from dire wolves that lived 11,500 and 72,000 years ago.
These dire wolf pups are a significant achievement for Colossal Biosciences and their “de-extinction” efforts for multiple species, including the wooly mammoth, the dodo, and the American bison. But the depth of this achievement is more nuanced than two happy, healthy, white-haired wolf pups.
“This brings in the flashy headlines, but I don't think that's the most important part of what's going on,” said Julie Meachen, a mammalian biologist at Des Moines University. “I want people to focus on conserving the animals we have today, and Colossal is doing a lot of work on conservation today while recreating animals from the past.”
Showing Your Work
Meachen is an authority on prehistoric DNA. She’s published several scientific papers analyzing DNA from Ice Age mammals, including samples recovered from Natural Trap Cave in Wyoming’s Bighorn National Forest.
The timing of Colossal Bioscience’s reveal of Romulus and Remus took her slightly by surprise. This isn’t just a genetic experiment – they’ve done their homework.
“The dire wolves, or whatever you want to call them, that Colossal made are based on a study that has actually been performed and written up but has not yet been accepted for publication,” she said. “It would show this is based on scientific data and not just on something they decided they wanted to do.”
Meachen has reason to be confident that the study would bolster the spectacle. She’s one of the co-authors of the yet-to-be-published paper.
“I didn't know anything about the genetically engineered wolves until about two weeks ago when they looped me in on it,” she said. “I wonder why they didn't wait until the paper came out to make the announcement because I figured that would bolster their case.”
Dire Circumstances
Dire wolves were common Ice Age predators, similar in size to gray wolves but with stronger jaws and teeth for preying upon megaherbivores like prehistoric bison, camels, and ground sloths that roamed North America during the Late Pleistocene. They are in the subfamily Caninae, which includes modern-day dogs, wolves, and foxes.
Meachen was co-author of a 2021 nuclear DNA study that determined the last common ancestor between dire wolves and modern-day wolves existed around 6 million years ago. That study included dire wolf DNA recovered in Wyoming.
“There was a Natural Trap Cave specimen sequence, but the DNA wasn’t complete enough,” Meachen said. “But that paper concluded that dire wolves and gray wolves were separated by 6 million years of evolution. That’s basically what we thought up until now.”
The yet-to-be-published study, which Meachen contributed to, analyzed new dire wolf DNA sequences from specimens recovered in Ohio and Idaho. Meachen said the latest research revealed that dire wolves weren’t as distantly related as her previous study indicated.
“We know this because the genome sequences we gathered from these two dire wolves are so much more expansive,” she said. “(Colossal) was able to gather a lot more genetic data on these two wolves than the five different samples in the 2021 study.”
The new research suggests that dire wolves are more closely related to modern wolves. Colossal used the findings of this research to inform their genetic resurrection of the extinct species.
“They’re not super closely related, but more closely related than we thought in the past,” Meachen said.
No Whitewashing
According to Meachen, Colossal recreated a completely reconstructed prehistoric genome and identified around 14 genes that determined distinct physical characteristics of dire wolves. They modified the gray wolf genome to “mirror” these traits, resulting in the successful birth of Romulus and Remus on Oct. 1, 2024.
“They identified the genes responsible for their size, coat color, big teeth, and a few other things,” she said. “Basically, what they’ve created is something that looks like a dire wolf.”
The most surprising thing for Meachen is the wolf pup’s coat color. The genetic research undertaken by her and her peers indicated that dire wolves had light-colored fur, which contradicts what paleontologists and biologists would assume about the predators given their environment.
“Dire wolves didn’t live in the Arctic or cold areas,” she said. “They lived in warmer climates. They are common in California and Tennessee, can be found as far north as Wyoming and Idaho, and are rare in Canada. You would assume they would be a darker color species, but they're not.”
Modern-day mammals tend to be colored to match their environment, like the white skin of Arctic polar bears. Since dire wolves aren’t “snowy animals,” Meachen doesn’t know why their fur would be white, which makes Colossal’s dire wolves all the more intriguing.
“The cubs are reflecting what the genetics say,” Meachen said. “Dire wolves have very light coats without any red or black in them. A white coat is essentially what they would have had.”
The two dire wolf pups created from prehistoric DNA have been named Romulus and Remus. (Courtesy Colossal Biosciences) 
A company revealed Monday it’s created the “world’s first de-extinct animals,” two wolf pups genetically modified to resemble extinct dire wolves. The same technology may soon "resurrect" woolly mammoths. (Courtesy Colossal Biosciences) 
The skulls of dire wolves at the George C. Page Museum at the La Brea Tar Pits in Los Angeles, California. Dire wolves are the most common predators found at the Late Pleistocene site, with noticeably larger teeth and stronger jaws than their modern counterparts. 
Recreations of the extinct dire wolf at the George C. Page Museum at the La Brea Tar Pits in Los Angeles, California. The dire wolves "resurrected" by Colossal Biosciences show these models are inaccurate, as the reconstructed genome revealed the extinct animals had white fur without any dark colors.
Extinction Is 'Forever'
While the world is enraptured by the undeniable achievement of Colossal’s dire wolf pups, the scientific community is skeptical and, in some cases, scornful of the company’s concept and investment in “de-extinction.”
“Colossal says that it is a dire wolf,” Meachen said, “but I think the overwhelming majority of scientists would say that it's not truly a dire wolf. They’d say it’s a gray wolf that looks like a dire wolf.”
For Meachen, the question is more complex. Her ongoing research at Natural Trap Cave and the famous La Brea Tar Pits in Los Angeles, California, is trying to answer questions about the prehistoric world that left dire wolves and other prehistoric species behind.
“We’re looking at the long bones and teeth of mammals to examine wear patterns, get body size estimation, and see if these things change through time and in association with a drying climate,” she said. “We've got a wonderful pollen record, isotopes from the dirt, and bacterial samples that give us a great climate record over the last 30,000 to 50,000 years. Now, we want to see if the animals are changing in response to that climate.”
Colossal’s dire wolf pups might be mirror images of their extinct brethren ago, but Meachen doesn’t plan on studying Romulus and Remus for her future research. They wouldn’t have any information she needs.
“I don’t think they’ll tell us anything new about the behavior of dire wolves because Colossal didn’t modify any genes implicated with certain behaviors,” she said. “They probably don’t know which genes are. That information is better gleaned from the fossil record.”
Prehistoric dire wolves probably lived, hunted, and had different social dynamics than their modern-day relatives. Without a time machine, the specifics of these behaviors are probably lost forever and would take more than genetic modification to “resurrect.”
“I think these are going to be animals that people can enjoy watching, but I don't think they're going to be especially informative about the behavior of dire wolves,” Meachen said.
Here Today
Despite what can or cannot be learned about the prehistoric past from Colossal’s de-extinction efforts, Meachen is supportive of their ongoing research. Learning more about the genomes of extinct animals might help prevent the extinction of their modern-day contemporaries.
“Resurrecting dire wolves and mammoths is the ‘gee whiz’ arm of Colossal,” Meachen said, “but in their defense, they are doing quite a lot of conservation work that I’d say is the most important part of the company.”
Meachen said their efforts to study and resurrect the dire wolf genome were adjacent to their conservation studies on modern-day red wolves, a critically endangered species from the southeastern United States.
For Meachen, the takeaway from the “resurrection” of dire wolves shouldn’t be simply marveling at what modern-day technology could mean for the future of extinction and prehistoric studies. What matters is what the world can do today to save its incredible biodiversity before it’s gone.
“The little kid in all of us is really excited about these dire wolves, but the message that gets lost in this announcement is what Colossal and other organizations are doing for modern-day conservation,” she said. “Yes, we can create these prehistoric animals, but I would like people to focus on conserving the animals we have today.”
Andrew Rossi can be reached at arossi@cowboystatedaily.com.
