Ancient Whale Bones Found Far Inland Replace Suspected Mammoth Fossils

Paleontologists searching for evidence of the last mammoths in Alaska recently encountered a significant surprise. While analyzing what they believed were fragments of mammoth vertebrae, they discovered the bones actually belonged to two different species of whale. This case of mistaken identity has created a fresh scientific puzzle about how whale bones ended up hundreds of kilometers from the sea.

Initially, the findings appeared to suggest something remarkable. Researcher Matthew Wooller and his team from the University of Alaska Fairbanks were using radiocarbon dating on fossils. Two specimens from a site named Dome Creek seemed to be only about 2,800 and 1,900 years old. This would have been a major discovery, potentially extending the timeline for mammoth survival in central Alaska by thousands of years. However, ancient DNA analysis revealed a different truth. The so-called "mammoth" bones belonged to a North Pacific right whale and a minke whale. Consequently, the scientific quest shifted from a hunt for the last mammoth to an investigation of how whale bones traveled so far inland.

Wooller's team has dated more than 300 mammoth fossils over four years through a project called Adopt-a-Mammoth. Their goal is to identify the most recent survivors of a species that died out at the end of the last Ice Age. The two Dome Creek specimens immediately attracted attention because their dates were unexpectedly recent.

“The radiocarbon data and their associated stable isotope data were the first signs that something was amiss,” Wooller and his colleagues wrote. The isotope data, which provides clues about an animal's diet, showed something peculiar. The chemical signatures indicated these supposed mammoths had consumed a diet rich in marine protein, similar to a modern whale's diet. This was highly unusual for animals that would have lived roughly 400 kilometers from the nearest coast. As the researchers noted, the evidence was starting to look "fishy."

The bones in question were vertebral growth plates, which are challenging to identify by sight alone, especially after centuries underground. Experts consulted by the team could not confidently determine the animal source just by looking. The original identification had been made in the early 1950s by fossil collector Otto Geist, who labeled them as mammoth based on their shape.

“The ancient DNA came to our rescue to secure the specimens’ true identity,” the researchers wrote. The DNA confirmed the whale identity but created a larger mystery: neither of these whale species is known to have lived in the interior of Alaska.

Setting aside these two misidentified samples, the established fossil record indicates that mammoths in Alaska died out around 11,000 years ago. However, many museum fossils have not been directly dated, leaving room for uncertainty. Some genetic evidence from permafrost hints that small groups might have survived in isolated parts of Alaska, Canada, and Russia until about 5,700 years ago. Determining precisely when and why mammoths vanished is a key question for scientists, who debate whether human hunting or climate change was the primary cause.

The Adopt-a-Mammoth project, which also involves the de-extinction company Colossal Biosciences, helps fund this expensive research. Supporters who donate receive updates and test results for a specific fossil. “Radiocarbon dates are expensive,” the researchers explained. Dating is a crucial first step before other analyses, like DNA testing, can be justified. So far, the project has successfully dated about 300 specimens, but the two from Dome Creek were clear outliers.

With the mammoth theory discarded, Wooller's team faced a new challenge: explaining how parts from two different whale species ended up 400 kilometers inland at Dome Creek. They considered three possibilities: the bones were carried by carnivores, transported by humans, or the whales themselves swam there. None of these explanations provided a perfect fit.

Whales do occasionally travel far up rivers. Minke whales, in particular, have been found as far as 1,000 kilometers inland in other parts of the world. Dome Creek is several miles from Alaska's large Tanana River. If it had been just the minke whale bone, the researchers might have accepted the story of one lost whale.

“That two individual whales of different species have made this improbable journey, died naturally, and left behind the very same skeletal element is not reasonable in our estimate,” the team wrote.

That left carnivores or humans as possible explanations. No known carnivore is likely to drag heavy bones hundreds of kilometers. Humans, however, are known to transport objects over long distances. Vertebral plates could have been useful as tools, trays, or cutting boards. The problem is that archaeologists have not found other whale bones at inland Alaskan sites, suggesting it was not a common practice. This explanation is possible, but it is not strongly supported by evidence.

The most plausible explanation may be a simple museum error. The paleontologist Otto Geist collected a vast number of bones from across Alaska in the mid-20th century. Records show that in 1951, the same day the museum received the shipment of bones from the inland Dome Creek site, it also received a collection from Dexter Point, a coastal site on Norton Bay. Geist had collected from both locations.

“It is possible that the two whale bones examined in the current study derived from this Norton Bay locale and were inadvertently included with the Dome Creek assemblage,” Wooller and his colleagues suggested. They acknowledge that this historical mix-up “may never be completely resolved.”

The mix-up provides a valuable lesson for scientific research. The Adopt-a-Mammoth project continues, now with a clear example of why scientists must thoroughly investigate unusual results. As the researchers concluded, the episode stresses the importance of “fully investigating anomalous radiocarbon results.” In simpler terms, if data looks suspicious, it might be pointing toward a completely different discovery—like a whale instead of a mammoth.

Journal of Quaternary Science, 2026 DOI: 10.1002/jqs.70040