Twelve and a half millennia after their extinction, dire wolves once again walk the Earth. The victorious resurrection of this prehistoric predator by Colossal Biosciences represents the world’s first complete de-extinction of a carnivorous mammal, transforming what once seemed an impossible scientific frontier into demonstrated reality. Three dire wolves—two males named Romulus and Remus, and a female named Khaleesi—now live at a secure facility, their existence bridging a temporal gap that spans most of human civilization.
The achievement resulted from a sophisticated combination of ancient DNA analysis, comparative genomics, and advanced reproductive technologies. The process began with the extraction of genetic material from two remarkably well-preserved specimens: a 13,000-year-old tooth and a 72,000-year-old skull. Despite the fragmentary nature of this ancient DNA, Colossal’s scientists identified approximately 20 key genetic differences across 14 genes that distinguish dire wolves from their closest living relatives, gray wolves. These differences account for the dire wolf’s distinctive characteristics, including its white coat, broader skull, more powerful jaws, and larger overall size.
Rather than attempting to recreate an entire dire wolf genome from limited ancient DNA fragments, Colossal’s scientists employed a more targeted approach. They harvested endothelial progenitor cells from living gray wolves and then used CRISPR technology to modify 14 identified genes, allowing them to express traits associated with the dire wolf. This methodology acknowledges that dire wolves and gray wolves share approximately 99.5% of their genetic makeup, making strategic modification of key differences more feasible than wholesale genomic reconstruction.
The modified cells underwent careful screening to ensure that the desired genetic changes had been successfully incorporated without unintended modifications elsewhere in the genome. Cell nuclei containing the engineered genetic material were then extracted and inserted into denucleated gray wolf ova—eggs with their original nuclear DNA removed. These modified ova developed into embryos, with 45 eventually transferred to the wombs of domestic hound mixes serving as surrogate mothers. Three pregnancies proved successful, resulting in the birth of the world’s first de-extincted dire wolves.
The first two dire wolves, Romulus and Remus, were born on October 1, 2024, via scheduled cesarean section. A third pup, Khaleesi, arrived on January 30, 2025, following a similar procedure. All three births were conducted under carefully controlled conditions to minimize risks to both the pups and surrogate mothers. The newborn dire wolves underwent a comprehensive veterinary assessment, confirming both their general health and the successful expression of the engineered dire wolf traits.
Now six months old, Romulus and Remus already weigh approximately 80 pounds, significantly larger than gray wolf pups of the same age. They display the characteristic white coats, broader skulls, and more powerful jaws that distinguished their prehistoric ancestors. Their continued development is being closely monitored at Colossal’s secure 2,000-acre facility, where they exhibit natural behaviors consistent with those of canid predators while adapting to a world that has undergone dramatic changes since their species last existed.
The resurrection methodology showcases significant technological advancements over previous de-extinction attempts. Unlike earlier cloning efforts that created only temporary revivals of recently extinct species, the dire wolf resurrection establishes a potentially self-sustaining population through genetic modifications that can be passed down to future generations. This approach addresses key limitations of previous de-extinction work, creating a more durable resurrection that could theoretically persist independently of continued technological intervention.
The technological achievement extends beyond the dire wolves themselves to include significant advances in reproductive medicine, genetic engineering, and comparative genomics. The successful birth of healthy pups from genetically modified embryos transferred to surrogate mothers demonstrates the viability of complex reproductive interventions spanning multiple species. These methodologies have potential applications for endangered species conservation, where similar techniques could help preserve genetic diversity in declining populations.
For Ben Lamm, Colossal’s CEO and co-founder, the resurrection of the dire wolf represents validation of the company’s ambitious vision. “This massive milestone is the first of many coming examples demonstrating that our end-to-end de-extinction technology stack works,” Lamm stated in the company’s announcement. “Our team took DNA from a 13,000-year-old tooth and a 72,000-year-old skull and made healthy dire wolf puppies.” This achievement establishes a methodological framework that will inform Colossal’s ongoing work with other de-extinction targets.
The resurrection has generated substantial scientific discussion about both the technological achievement and its implications. While some researchers have questioned whether these animals should be considered “true” dire wolves, given that they are essentially modified gray wolves, others maintain that successfully resurrecting the functional essence of an extinct species represents a legitimate de-extinction regardless of methodological details. This debate raises deeper questions about how species identity should be understood in an era when genetic technologies are increasingly blurring traditional taxonomic boundaries.
Beyond its scientific implications, the resurrection of the dire wolf carries profound cultural significance. George R.R. Martin, creator of the “Game of Thrones” series that reintroduced dire wolves to popular consciousness, serves as a Cultural Advisor to Colossal. Upon seeing the living dire wolves, Martin reportedly had an emotional reaction, later writing in his personal blog that witnessing the animals brought a profound sense of how science can manifest what previously existed only in imagination and paleontological inference.
As Colossal continues monitoring the development of Romulus, Remus, and Khaleesi, each day provides new data about a species that had disappeared from Earth for millennia. Their behaviors, vocalizations, growth patterns, and social interactions offer unprecedented insights into dire wolf biology that extend far beyond what paleontologists could determine from fossil evidence alone. Each howl that echoes through Colossal’s facility represents not merely a technological achievement but a sound that had vanished from Earth’s acoustic landscape until genetic resurrection made it possible once more.