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For over 12,000 years, the dire wolf existed only in the fossil record. These powerful Ice Age predators, distinct from today’s gray wolves, disappeared from North America at the end of the Pleistocene epoch, leaving behind only bones and scientific speculation about what made them unique.
In 2025, our team changed that forever. We successfully brought dire wolves back from extinction, with three healthy pups—Romulus, Remus, and Khaleesi—representing the world’s first functionally de-extincted animals. This achievement demonstrates that our end-to-end de-extinction technology stack works, opening new possibilities for both species revival and conservation.
Deciphering the Genetic Blueprint of Colossal’s Dire Wolves
Our dire wolf work began with extracting genetic material from carefully preserved fossils—a 13,000-year-old dire wolf tooth and a 72,000-year-old skull. Unlike the thousands of dire wolf specimens found in places like the La Brea Tar Pits, these fossils had been protected from heat and acidification, preserving enough DNA for our scientists to work with.
Working with fragmentary ancient DNA presents extraordinary challenges. We essentially needed to reconstruct a complete genetic blueprint from tiny, degraded pieces scattered across millennia. Our team of bioinformaticians utilized machine learning algorithms to fill in the gaps, comparing ancient DNA fragments with the genomes of modern canids to predict the complete dire wolf genome.
This analysis revealed that dire wolves were far more than enlarged gray wolves—they represented a completely separate lineage that had evolved in the Americas for millions of years. Our genetic research uncovered the specific traits that made these ancient predators unique.
Engineering Traits Lost to Time
Through our genomic analysis, we identified 14 important genes containing 20 distinct genetic variants that give dire wolves their characteristic features. These included genes influencing their larger size, more muscular build, wider skulls, bigger teeth, thick light-colored coats, and even their unique howling vocalizations.
Some of these variants, like the three gene variants for light coat color, are completely absent in modern gray wolves. Scientists identified genetic variants for the dire wolf’s larger size, white fur, and powerful build, all of which are now evident in these resurrected pups.
“Our team took DNA from a 13,000 year old tooth and a 72,000 year old skull and made healthy dire wolf puppies,” said Ben Lamm, Colossal CEO and co-founder. “It was once said, ‘any sufficiently advanced technology is indistinguishable from magic.’ Today, our team gets to unveil some of the magic they are working on and its broader impact on conservation.”
Setting New Records in Genetic Engineering
Creating the dire wolves required unprecedented precision in genetic engineering. We made 20 precise genetic edits to resurrect dire wolf traits—setting a new record for the highest number of precise genetic edits in any living vertebrate species. This surpassed our previous achievement with the Colossal woolly mouse, which contained 8 mammoth gene edits.
Our approach represents functional de-extinction: the process of generating an organism that both resembles and is genetically similar to an extinct species by resurrecting its lost lineage of core genes; engineering natural resistances; and enhancing adaptability that will allow it to thrive in today’s environment of climate change, dwindling resources, disease and human interference.
We used CRISPR gene editing to modify living canid cells, essentially rewriting their genetic code to match that of dire wolves. These edited cells were then used in a cloning process, with embryos implanted into surrogate mothers—domestic dogs, who are now living in their forever homes after going through an American Humane Society training program. After approximately 65 days of gestation, all three pups were born healthy via cesarean section.
Advancing Conservation Through De-extinction Technology
While bringing back dire wolves captures attention, we’ve simultaneously applied these same technologies to help critically endangered species. Through the Dire Wolf Project, we developed a novel non-invasive cloning technique that uses a simple blood draw rather than tissue. Alongside our dire wolf announcement, we revealed the successful cloning of four critically endangered Red ‘Ghost’ Wolves using identical techniques. Carrying a high percentage of ancestral Red Wolf DNA, these new individuals represent a significant conservation breakthrough for the future of the species.
With fewer than 20 remaining in the wild, the remaining Red Wolf population is facing a severe genetic bottleneck. Our cloned Red ‘Ghost’ Wolves, derived from three distinct genetic founder lines, could increase the genetic diversity of the captive population by 25%.
Deciphering the Genetic Blueprint of Colossal’s Dire Wolves
Our dire wolf work began with extracting genetic material from carefully preserved fossils—a 13,000-year-old dire wolf tooth and a 72,000-year-old skull. Unlike the thousands of dire wolf specimens found in places like the La Brea Tar Pits, these fossils had been protected from heat and acidification, preserving enough DNA for our scientists to work with.
We’re also applying our gene-editing toolkit to other conservation challenges. Our scientists are working with species like the pink pigeon—a bird that suffers from a severe genetic bottleneck—introducing greater genetic diversity into embryos to improve the species’ long-term viability.
Expanding Our De-extinction Portfolio
The dire wolf success validates our approach for other species restoration projects. We’re already applying similar methods to our woolly mammoth program, along with our thylacine and dodo revival efforts.
Since unveiling our thylacine de-extinction program in 2022, we’ve made innovative advancements toward the species’ rebirth. We recently announced that we’ve successfully sequenced the entire genome of the Tasmanian tiger. As Dr. Andrew Pask put it, “Absolutely ever single bit of code, from one end to the other.”
Our expanding portfolio now includes the South Island giant moa, making it our fifth de-extinction target. Each project builds on technologies and methodologies developed through previous work, creating an increasingly powerful platform for species restoration.
Ensuring Ethical Care and Development
The three dire wolf pups are thriving on our 2,000 acre secure expansive ecological preserve, certified by the American Humane Society. We employ full-time animal care staff to support the wolves’ physical and mental well-being, with facilities that include naturalistic habitats and an on-site veterinary clinic.
Our transparent approach includes regular updates on their development, demonstrating our commitment to ethical de-extinction practices. The pups are meeting all developmental milestones as they mature, showing the same behaviors and growth patterns we’d expect from healthy canids.
A Foundation for Future Conservation
“Preserving, expanding, and testing genetic diversity should be done well before important endangered animal species like the red wolf are lost,” said Dr. George Church, our co-founder and Harvard geneticist. “Another source of ecosystem variety stems from our new technologies to de-extinct lost genes, including deep ancient DNA sequencing, polyphyletic trait analyses, multiplex germline editing, and cloning. The dire wolf is an early example of this, including the largest number of precise genomic edits in a healthy vertebrate so far. A capability that is growing exponentially.”
Our work demonstrates how de-extinction science creates new tools for conservation biology. Rather than simply preventing extinctions, we can now actively restore genetic diversity and ecological function. These capabilities become increasingly valuable as climate change and habitat loss continue pressuring wildlife populations worldwide.
As Mark Fox, Tribal Chairman of the MHA Nation, reflected on the dire wolf’s birth, it “symbolizes a reawakening—a return of an ancient spirit to the world,” underscoring our responsibility to protect the balance of life.
The dire wolves walking the earth today represent more than a scientific achievement—they’re proof that with innovative research and advanced biotechnology, we can address biodiversity loss in ways previously impossible. Through our growing conservation efforts, we’re working to make extinction a thing of the past, creating new hope for both recovering what’s been lost and protecting what remains.
