woolly mammoths extinction: In 2024, researchers challenged a decades-old theory about the extinction of woolly mammoths that they didn’t die out the way we thought

For years, scientists believed that the last woolly mammoths disappeared because their isolated populations were too inbreeding to survive. However, a new study conducted in 2024 changes this long-held view. By examining ancient DNA from Wrangel Island mammoths, researchers now believe that a sudden event rather than genetics alone may have brought about the end of the species.

New research published in the journal Cell suggests the story may be much more complex, USA Today reports.

The study shows that the last population of woolly mammoths living on Wrangel Island in the Arctic may have survived genetically for thousands of years before a sudden event wiped them out.

Researchers now believe that “some other type of sudden event, such as a disease outbreak or dramatic change in the environment,” may have caused their extinction rather than genetic decline alone.

How did mammoths become isolated?

The study focused on Wrangel Island, located off the northeastern coast of Siberia, where a small group of woolly mammoths survived long after the species had disappeared elsewhere. Mammoths were stranded when the Ice Age ended more than 12,000 years ago, according to Love Dalén, senior author of the study and professor of evolutionary genomics at the Center for Palaeogenetics in Stockholm.

As massive ice sheets melted, rising sea levels flooded the land bridge that once connected Wrangel Island to the Siberian mainland.

“Presumably the mammoths were passing through Wrangel Island,” he added, “just at the time when sea level separated Wrangel from the mainland, so they got stranded there.”

When researchers first isolated the mammoths, “Our analysis shows that they were down to about eight breeding individuals,” Dalén said, according to a report by USA Today.

Despite such a small start, the population rebounded surprisingly quickly.

“The population actually grew very rapidly, almost exponentially, up to 300 people in about 20 generations.”

Scientists are still unsure why the island was able to support mammoths for more than 6,000 years, but Dalén noted that the abundance of plant life and the absence of large predators and humans may have played important roles.

What did DNA analysis reveal?

To better understand the mammoths’ final years, researchers examined the genomes of 21 Siberian woolly mammoths.

The study included DNA from 14 mammoths that lived on Wrangel Island between 9,200 and 4,300 years ago, as well as seven mainland ancestors for comparison.

The genomes were reconstructed from nearly 400 DNA samples collected from mammoth bones, tusks and tusks, including samples collected during an expedition to Wrangel Island in 2017.

The researchers removed powdered material from inside the mammoth tusks using a dental drill before purifying them to obtain DNA for analysis.

Genetic evidence has shown that although mammoths started with an extremely small breeding population, they remained genetically stable for thousands of years. This finding challenges the long-held belief that inbreeding alone drove them to extinction.

What could have caused their extinction?

Although mammoths survived on Wrangel Island for millennia, the study suggests that their final extinction likely occurred suddenly.

Dalén said the researchers focused on the last 200 years before the species went extinct. “Our youngest genome is 4,300 years old, and all the data suggests that mammoths became extinct at 4,100 years old,” he said. Scientists believe that a small population of about 200 mammoths is particularly vulnerable to unexpected events.

“A small population like 200 mammoths would probably be very sensitive to a small change in the environment,” Dalén said.

Researchers have suggested several possibilities, including a short-term climate crisis or a bush fire damaging the island’s vegetation.

Another theory is that a pathogen such as influenza carried by migratory birds may have reached the island and spread through the isolated population.

“I don’t know if we’ll be able to figure this out, but at least we have some ideas,” Dalén said.

While the exact cause remains unclear, new findings suggest that the woolly mammoth’s final chapter was likely shaped by an unexpected event rather than inbreeding alone, challenging one of the most widely accepted explanations for the species’ extinction.

FAQ

Where did the last woolly mammoths live?
They survived on Wrangel Island in the Arctic off the coast of northeastern Siberia.

What does the new study suggest?
This suggests that their extinction may have been caused by a sudden event, not just inbreeding.