Game of Thrones

In 2011, HBO’s Game of Thrones Season One first aired on TV.  Adapted from George R. R. Martin’s Song of Ice & Fire series, the show became an instant hit worldwide. One of the leading figures was that of the direwolf.

The Historic Direwolf

“The actual dire wolf (Aenocyon dirus[10] /iːˈnɒsaɪ.ɒn ˈdaɪrəs/) is an extinct canine. It is one of the most famous prehistoric carnivores in North America, along with its extinct competitor Smilodon. The dire wolf lived in the Americas and eastern Asia during the Late Pleistocene and Early Holocene epochs (125,000–9,500 years ago). The species was named in 1858, four years after the first specimen had been found. Two subspecies are recognized: Aenocyon dirus guildayi and Aenocyon dirus dirus. The largest collection of its fossils has been obtained from the Rancho La Brea Tar Pits in Los Angeles.”1

The dire wolf was about 20 percent larger on average than the largest modern gray wolves (Canis lupus): the Yukon wolf and the northwestern wolf.

Its skull and dentition matched those of C  lupus, but its teeth were larger with greater shearing ability, and its bite force at the canine tooth was stronger than any known Canis species. These characteristics are thought to be adaptations for preying on Late Pleistocene megaherbivores, and in North America, its prey is known to have included western horses, ground sloths, mastodons, ancient bison, and camels.

James Gorman writes, “[T]he first sequencing of the dire wolf genome showed an unexpectedly large genetic separation between the two species, big enough that the dire wolf is not just a separate species but a separate genus…The last common ancestor of the gray wolf and the dire wolf was about 5.7 million years ago, the researchers reported. And another surprise was that the dire wolf didn’t seem to interbreed with other species — as dogs, wolves, coyotes and other canids do. In evolutionary terms, it met a lonely end.”3

Attempts to Recreate the Direwolf

In 2024 and 2025, the biotech firm Colossal Biosciences claimed to have achieved a “de-extinction” milestone by using ancient DNA from fossils to edit the genome of the modern gray wolf. The outcome was three hybrid pups that resemble the extinct dire wolf. The pups were born via surrogate mothers using IVF and advanced gene editing. The two males, Romulus and Remus, were born on October 21, 2024; the female, Khaleesi, was born on January 30, 2025.

Because true genetic cloning requires a living cell of the extinct species (which are unavailable due to decay), scientists used a process called proxy de-extinction. They extracted DNA from ancient dire wolf fossils and mapped out the original genome. 

They then used CRISPR technology to compare this genome with that of the modern grey wolf. They rewrote 14 key genes in gray wolf Endothelial progenitor cells (EPCs) to produce animals that express 20 traits said to be characteristic of direwolves

These edited cells were cloned and fertilized in vitro to produce embryos, which were then implanted into surrogate dog mothers.

These animals are not “true” dire wolves, but rather genetically modified hybrid gray wolves. They are genetically still 100% gray wolves, with a handful of genes altered for appearance rather than a true replication of the ancient species. The project has faced scrutiny in scientific communities, with critics suggesting that it was heavily marketed toward pop culture imagery rather than traditional, peer-reviewed studies of de-extinction.

The IUCN Species Survival Commission‘s Canid Specialist Group officially declared that the three animals are neither dire wolves nor proxies of the dire wolves based on the IUCN SSC guiding principles on creating proxies of extinct species for conservation benefit. They commented that creating phenotypic proxies does not change the conservation status of an extinct species and may instead threaten the extant species such as gray wolves. Therefore, since the claimed proxies do not conform with the IUCN SSC guidelines, have no ecological niche left today and “will not restore ecosystem function”, they concluded that the Colossal Biosciences’ project “does not contribute to conservation.” The Colossal Biosciences released Alignment of Colossal’s Dire Wolf De-Extinction Project with IUCN SSC Guiding Principles in response.

The Game of Thrones

In his epic fantasy novel series A Song of Ice and Fire, George R.R. Martin created a fictional world, where a series of Great Houses ruled over the continents of Westeros and Essos. House Stark of Winterfell was a Great House of Westeros, and the royal house of the Kingdom of the North. Its sigil was a grey direwolf‘s head facing sinister on a white field over green.

Martin characterized the dire wolf—which he spelled “direwolf”—as an unusually large and intelligent species of wolf.

In the opening scenes of the HBO adaptation of the series, Eddard Stark—head of House Stark—together with his sons Robb and Bran, his “bastard” son Jon Snow and his ward Theon Greyjoy, found a dead female direwolf. It had died after giving birth to five pups, which still huddled against the corpse for warmth.

Eddard advocated killing the pups out of mercy, but Jon convinced his “father” that this was an omen: the direwolf was the symbol of House Stark. Eddard had five trueborn children. Eddard agreed that his children could have the pups, but only if they raised them themselves with no help from the servants.

Just as the party was leaving, Jon found a sixth pup, an albino runt of the litter. Theon mockingly pointed out that this one belonged to Jon.6

The puppies in this scene were all Northern Inuits.

When Eddard traveled south to serve as Hand of the King to King Robert Baratheon, he brought his daughters Sansa and Arya, along with their pet direwolves Lady and Nymeria—the first direwolves to be seen so far south in hundreds of years. After Nymeria attacked Prince Joffrey, Arya drove her away to prevent her execution. Robert commanded Eddard to kill Lady instead.

Altogether, the direwolves remained loyal to their masters, the remaining four staying by their sides until eventually those of Robb, Bran, and Theon had also been killed. By the end of the series, only two of the original six direwolves were still alive: Nymeria—who traveled the Riverlands, leading a pack of gray wolves, and who chose not to return to Arya—and Jon’s direwolf, Ghost, who stayed by Jon’s side.

Game of Thrones and Northern Inuit Dogs

HBO® could not use real wolves while filming, due to laws in the U.K. and to the involvement of small children in the series. Instead, the production team decided on Northern Inuit dogs as looking the most like a real wolf.

The Northern Inuit Society (NIS) provided Northern Inuit dogs to assist with filming the pilot for Season One a year before it aired on TV. The Society was ultimately given the contract for NIS breeders to provide NIs to play both the puppy and young direwolves for the first season, due to the dogs’ easygoing nature and trainability.4

In Season 2, real wolves were used to portray the adolescent direwolves. Using a variety of camera tricks and techniques, along with CGI (Computer Generated Imagery), the shots were augmented to make the wolves appear larger. They were then composited with the background and actors for the final shots. As a result, the direwolves in Season Two and following were played by real-life wolves that had been super-sized in post-production.

Sources & Resources

The content of this page was adapted, cited, paraphrased, and borrowed from the following sources:

  1. Dire Wolf. Wikipedia. https://en.wikipedia.org/wiki/Dire_wolf
  2. Anderson, Andrea. 2021. Dire Wolves Were Real—And Even Stranger Than We Thought. National Geographic. https://www.nationalgeographic.com/animals/article/dire-wolf-dna-study-reveals-surprises.
  3. Gorman, James. 2021. DNA Reveals the Real Lives of ‘Game of Thrones’ Dire Wolves. https://www.nytimes.com/2021/01/13/science/dire-wolf-genome.html
  4. Game of Thrones. Northern Inuit Society. http://nisociety.com/about-the-breed/game-of-thrones/
  5. House Stark. House of the Dragon Wiki. https://gameofthrones.fandom.com/wiki/House_Stark
  6. House of the Dragon Wiki. https://gameofthrones.fandom.com/wiki/Direwolf
  7. 7 Celebrities Who Fell in Love With Their Animal Co-Stars So Much They Refused to Be Separated. bright Side.
    https://brightside.me/wonder-people/7-celebrities-who-fell-in-love-with-their-animal-co-stars-so-much-they-refused-to-be-separated-795342/.
  8. Lyons, Margaret. 2013. Sansa Stark Adopted Her Dire Wolf in Real Life. Vulture (August 19). https://www.vulture.com/2013/08/sansa-stark-dire-wolf-sophie-turner.html.
  9. Dog Times. Game of Thrones actress adopts her “direwolf”.  https://dogtime.com/trending/18280-game-of-thrones-actress-sophie-turner-adopts-direwolf.