Last summer, a mammoth tusk hunter exploring the shores of the Tirekhtyak River in Siberia’s Yakutia region unearthed the fully intact head of a prehistoric wolf. Preserved by the region’s permafrost, or permanently frozen ground, for some 32,000 years, the specimen is the first partial carcass of an adult Pleistocene steppe wolf—an extinct lineage distinct from modern wolves—ever found.
The discovery, first reported by the Siberian Times, is poised to help researchers better understand how steppe wolves compared with their contemporary counterparts, as well as why the species eventually died out.
As Marisa Iati writes for the Washington Post, the wolf in question was fully grown, likely aged 2 to 4 years old, at the time of its death. Although photographs of the severed head, still boasting clumps of fur, fangs and a well-preserved snout, place its size at 15.7 inches long—the modern gray wolf’s head, in comparison, measures 9.1 to 11 inches—Love Dalén, an evolutionary geneticist at the Swedish Museum of Natural History who was filming a documentary in Siberia when the tusk hunter arrived on the scene with the head in tow, says that media reports touting the find as a “giant wolf” are inaccurate.
“It is not that much bigger than a modern wolf if you discount the frozen clump of permafrost stuck to where the neck would [normally] have been,” Dalén explains to Smithsonian.com.
According to CNN, a Russian team led by Albert Protopopov of the Republic of Sakha’s Academy of Sciences is currently building a digital model of the animal’s brain and the interior of its skull.
David Stanton, a researcher at the Swedish Museum of Natural History who is leading genetic analysis of the remains, tells Smithsonian.com that given the head’s state of preservation, he and his colleagues are hopeful that they can extract viable DNA and use it to sequence the wolf’s genome. This work, expected to last at least another year, will eventually be published in a peer-reviewed scientific journal.
For now, it remains unclear exactly how the wolf’s head became separated from the rest of its body. Speaking with Smithsonian.com, Tori Herridge, an evolutionary biologist at London’s Natural History Museum who was part of the team filming in Siberia at the time of the discovery, says that a colleague, Dan Fisher of the University of Michigan, thinks scans of the animal’s head may reveal evidence of it being deliberately severed by humans—perhaps “contemporaneously with the wolf dying.” If so, Herridge notes, the find would offer “a unique example of human interaction with carnivores.” Still, she concludes in a post on Twitter, “I am reserving judgment until more investigation [is] done.”
Dalén echoes Herridge’s hesitancy, saying that he has “seen no evidence convincing” him that humans cut off the head. After all, it’s not uncommon to find partial sets of remains in the Siberian permafrost. If an animal was only partially buried and subsequently frozen, for example, the rest of its body could have decomposed or been eaten by scavengers. Alternatively, it’s possible that shifts within the permafrost over thousands of years led the carcass to break into multiple pieces.
According to Stanton, steppe wolves were “probably slightly larger and more robust than modern wolves.” The animals had a strong, wide jaw equipped for hunting large herbivores such as woolly mammoths and rhinos, and as Stanton tells USA Today’s N’dea Yancey-Bragg, went extinct between 20,000 to 30,000 years ago, or roughly the time when modern wolves first arrived on the scene. If the researchers successfully extract DNA from the wolf’s head, they will attempt to use it to determine whether the ancient wolves mated with modern ones, how inbred the older species was, and if the lineage had—or lacked—any genetic adaptations that contributed to its demise.
To date, the Siberian permafrost has yielded an array of well-preserved prehistoric creatures: among others, a 42,000-year-old foal, a cave lion cub, an “exquisite ice bird complete with feathers,” as Herridge notes, and “even a delicate Ice Age moth.” According to Dalén, these finds can largely be attributed to a surge in mammoth tusk hunting and increased melting of permafrost linked with global warming.
Speaking with Smithsonian.com, Stanton concludes, “The warming climate … means that more and more of these specimens are likely to be found in the future.”
At the same time, he points out, “It is also likely that many of [them] will thaw out and decompose (and therefore be lost) before anyone can find ... and study them.”