Imagine hearing a howl in the wilderness—only to learn it belongs to a creature extinct for 10,000 years. Welcome to the brave new world of de-extinction. In April 2025, Colossal Biosciences announced it had created three living proxies of the ice-age predator we know as the dire wolf.
Here’s the scoop on how this real-life Jurassic Park unfolded—and why it has everyone, from tribal leaders to conservationists, howling with excitement and concern.
Dire wolves once roamed North America in packs—but by the end of the Pleistocene, around 10 millennia ago, they vanished from the fossil record. Colossal’s team started by hunting for the best ancient DNA scraps they could find: a 13,000-year-old tooth and a 72,000-year-old skull fragment. Despite extensive damage, these samples offered enough genetic clues to map the dire wolf genome.
Next came CRISPR gene-editing magic. Scientists compared the dire wolf’s DNA blueprint to that of today’s gray wolf, pinpointing 14 key genes responsible for heavier builds, thicker fur, and larger feet—traits that made dire wolves so fearsome. They then rewrote those 14 genes into gray wolf stem cells, creating 20 precise edits that, in effect, transformed ordinary wolf DNA into a “dire wolf proxy,” all without using a single strand of ancient DNA in the final genome.
In the lab, these edited cells became embryos that were implanted into gray wolf surrogates—dog moms, in essence. The result? Two male pups, Romulus and Remus, born October 1, 2024, and a female named Khaleesi, born January 30, 2025. They’re adorable, floppy-eared bundles of science, each weighing just a few pounds—for now. But they’re growing fast. Even at this stage, their wider skulls and muscular builds already set them apart from regular wolf pups.
Fans of Game of Thrones know dire wolves as massive, almost mythical beasts—but don’t expect the same fantasy-sized giants here. Ancient dire wolves were bigger than today’s gray wolves, but not quite as enormous as their on-screen counterparts. These new pups are likely to hit around 120–140 pounds at maturity, compared to the fictional 200-pounders.
Early behavior tests suggest more than puppy-like curiosity: these pups exhibit higher bite pressure in miniature trials and den-burrowing instincts that match dire wolf trackways preserved in fossil beds. They live in a secure, 2,000-acre sanctuary in Texas, where researchers observe everything from how they greet each other to howling patterns—long thought lost to prehistory.
Don’t expect to cross paths with these colossal animals in Yellowstone or even Siberia, places where Pleistocene canids once thrived. Introducing apex predators into a world that no longer has space or balance for them would raise serious ecological and ethical concerns. As MHA Nation Tribal Chairman Mark Fox reflected, “the dire wolf carries the echoes of our ancestors… Its presence would remind us of our responsibility as stewards of the Earth.”
But Jeremy Austin, Director of the Australian Centre for Ancient DNA, says they are “ not a dire wolf under any definition of a species ever,” and that rewilding them might threaten existing gray wolf populations rather than mend broken ecosystems. After all, ecosystems have shifted over 10,000 years—releasing a near-extinct predator could ripple unpredictably through modern food webs.
The cloning breakthrough is undeniably jaw-dropping—but it also sparks a howling debate: should humans resurrect long-gone species? Animal-welfare advocates worry about the health and well-being of de-extincted animals, born in labs and raised under human care. Critics ask if lab-grown proxies truly honor an extinct lineage or simply exploit our technological prowess.
Colossal plans to scale up breeding, refining genetic edits to boost health and diversity. They’re also developing “biological insurance” for thylacines (Tasmanian tigers), aiming to resurrect them within a decade —an announcement made in collaboration with the University of Melbourne. Meanwhile, regulators are scrambling to create guidelines for de-extinction, weighing ecological impacts, animal welfare, and legal frameworks.
For now, Romulus, Remus, and Khaleesi are the world’s first “dire wolves” in 10,000 years. One thing’s certain: we’ve entered the age where extinction might no longer be forever—and that’s as eerie as it is exciting.
Want to learn about more extinct species that could be making a comeback? Check out 5 Extinct Species That Could Walk (or Waddle) the Earth Again .
