The dire wolf was real. Long before it became famous from fantasy novels and television, it hunted across the Americas, from Alberta in Canada to Bolivia and Chile, and it died out about 10 000 years ago. Its bones turn up in great numbers: more than 4 000 dire wolves have been pulled from the La Brea Tar Pits in Los Angeles alone. In 2025 it was in the news again, when a company announced it had brought the species back. It had not.
Not quite a wolf
For more than a century the dire wolf was thought to be a close cousin of the grey wolf, a bigger, heavier version of the same animal. Ancient DNA changed that. A 2021 study found that its lineage had split from the one leading to grey wolves and coyotes about 5.7 million years ago, and it saw no sign of interbreeding with either, even after they reached North America. The researchers revived an old genus name for it, Aenocyon, meaning “terrible dog”. On this reading its wolf-like shape is convergent evolution: two separate lines arriving at the same design for the same job.
A later genome study with much better coverage, led by scientists at the company Colossal Biosciences and published in 2026, argued instead for a mixed ancestry: about 60 per cent from the side of the family that includes wolves and coyotes and about 40 per cent from the line of South American canids, with a split about 4.5 million years ago. Its figures differ between versions of the paper, and most of its authors work for the company or its partners.
A heavyweight hunter
A dire wolf had a body shaped much like a large northern grey wolf, but a broader, heavier skull that could reach 31 cm or more, bigger teeth with more shearing power, and a stronger bite for its size. Average weights were about 60 to 68 kg, and the bones suggest none weighed more than about 110 kg. It was not much longer than a big modern wolf, but it was more heavily built.
Its fossils are concentrated in California, Florida and the Ozarks, and it was rare north of about 42 degrees latitude. Its prey is thought to have included horses, bison, camels, ground sloths and peccaries, and at La Brea chemical traces in its bones point mainly to young bison and camels. Like grey wolves, it probably hunted in packs. A 2025 study of finds from Iowa used protein fingerprints to confirm their identity and compared their chemistry with Smilodon from the same region: the two big predators seem not to have competed closely for the same prey there.
Gone with the big game
Dire wolves vanished at the end of the last Ice Age, along with most of the large animals they hunted. At La Brea, a 2023 study dated their disappearance, and that of six other large species, to about 12 900 years ago, after large fires in a warming and drying landscape. Elsewhere they lasted a little longer. Climate change, the loss of big prey and competition, perhaps with grey wolves and human hunters, are all thought to have played a part.
The 2025 “dire wolves”
In April 2025 Colossal Biosciences announced three pups, Romulus, Remus and Khaleesi, which it called dire wolves. They were grey wolves with 20 edits in 14 genes, chosen after studying ancient dire wolf DNA from a 13 000-year-old tooth and a 72 000-year-old ear bone. No ancient DNA was put into them. One of the edits gave them white fur. The company says dire wolves carried genes for a light coat, a claim that no surviving hair can test.
Independent scientists were blunt. The IUCN’s specialist group on wild dogs concluded that the pups are neither dire wolves nor valid stand-ins for them, and that the project does nothing for conservation. A month later Colossal’s own chief scientist described them as grey wolves with 20 edits and called “dire wolf” a colloquial name. The real dire wolf remains extinct, known only from its bones.
