14,400-Year-Old Woolly Rhinoceros Genome Reveals No Signs of Recent Inbreeding

The Woolly Rhino (Coelodonta antiquitatis) is a fascinating cold-adapted herbivore that went extinct approximately 14,000 years ago. Despite its extinction, little is understood about the factors leading to its population decline. A recent study by scientists from the Center for Paleogenetics and Stockholm University successfully generated a high-coverage genome from one of the last known woolly rhinoceros specimens, recovered from the stomach of a frozen wolf pup in Siberian permafrost. This genomic analysis, when combined with data from two other late Pleistocene woolly rhinoceroses, reveals that the population was stable, lacking any genomic evidence of rapid declines before extinction—contrasting sharply with other endangered and extinct species.



This depiction of a Pleistocene landscape in northern Spain features woolly mammoths (Mammuthus primigenius), equids, woolly rhinoceros (Coelodonta antiquitatis), and the European cave lion (Panthera leo spelaea) alongside reindeer carcasses. Image credit: Mauricio Anton.

The woolly rhino, a cold-adapted herbivore, first appeared around 350,000 years ago and thrived across northern Eurasia until its extinction roughly 14,000 years ago.

Its habitat began to contract eastward approximately 35,000 years ago, likely due to adverse environmental conditions in Western Europe.

This species persisted in northeastern Siberia and showcased complex range shifts in response to changing environments until disappearing from the fossil record.

Earlier genomic studies have shown no signs of recent inbreeding in individuals dating back 18,400 and 48,500 years; however, this is the first time an entire genome has been successfully recovered from a specimen so close to the extinction timeline.

“Recovering genomes from individuals that lived just before extinction is challenging but crucial for understanding a species’ decline, which can inform current conservation efforts for endangered species,” stated Dr. Camilo Chacon-Duque, the lead author of the study.

The newly sequenced woolly rhinoceros genome was sourced from muscle tissue found within a permafrost-preserved wolf pup recovered from northeastern Siberia.

Radiocarbon dating indicates that both the wolf and the tissue are about 14,400 years old, making it one of the youngest known woolly rhino remains.

“Sequencing the entire genome of an Ice Age animal found in another animal’s stomach is unprecedented,” Dr. Chacon-Duque commented.

By comparing this genome with two previously published late Pleistocene woolly rhinoceros genomes, researchers assessed genome-wide diversity, inbreeding, genetic load, and population size changes before extinction.

Results indicated a lack of long homozygous segments typically seen in populations experiencing recent inbreeding, suggesting stability in population size just centuries before extinction.

“DNA extraction from such a rare sample was both thrilling and immensely challenging,” said Solveig Gjonsdottir, the lead study author.

Researchers also mapped changes in effective population size and found no decline at the beginning of the Inter-Bolling-Allerod warm period, starting around 14,700 years ago.

The data imply that woolly rhinoceros extinction likely happened rapidly during this climate change period, or over a timeframe that left no detectable genomic evidence.

“Our analysis reveals an unexpectedly stable genetic pattern, showcasing unaltered inbreeding levels over tens of thousands of years prior to the woolly rhino’s extinction,” said co-author Dr. Edana Lord.

“Our findings indicate that woolly rhinos maintained viable populations for 15,000 years following the arrival of the first humans in northeastern Siberia. This suggests that climate warming, rather than human hunting, was the primary driver of their extinction,” co-author Professor Rab Dalen concluded.

For further details, refer to the study results published in Genome Biology and Evolution.

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Solveig M. Gudjonsdottir et al. 2026. Genome reveals no recent inbreeding in endangered woolly rhinoceros sample found in ancient wolf stomach. Genome Biology and Evolution 18 (1): evaf239; doi: 10.1093/gbe/evaf239

Source: www.sci.news

Bad luck, not inbreeding, led to the demise of the last mammoths on Earth

Artist’s impression of the last mammoth

Beth Zaiken

About 10,000 years ago, a handful of woolly mammoths washed up on an island off the Siberian coast in the Russian Arctic. Over the next few thousand years, this small group of perhaps eight animals grew into a stable population of 200-300 animals before going extinct about 4,000 years ago. These mammoths are the last known population of woolly mammals on Earth, and may have survived into modern times but for some bad luck.

The history of these mammoths has been clarified through genetic research. Love Darren A team from Stockholm University in Sweden and their colleagues looked at DNA from 14 mammoths from Wrangel Island and seven from the mainland, dating back to before melting ice sheets caused sea levels to rise and isolate them, covering a combined genetic history of 50,000 years.

The researchers’ analysis found that despite the small population, inbreeding wasn’t the cause of the mammoth’s extinction: While small genetic mutations accumulated, Dallen said, the population was good at eliminating larger, harmful ones.

“We can demonstrate that it’s unlikely that inbreeding or genetic disease caused the population to slowly decline and go extinct,” he said. “Despite the inbreeding, the population did well.”

Mammoth tusk found on Wrangel Island

Love Darren

But the team found that individual mammoths were affected by genetic diseases, and that this negative impact at the individual level had been ongoing for thousands of years. “This means that today’s endangered species, which in most cases were at risk of extinction until very recently, are likely to continue to suffer from genetic diseases for hundreds of generations to come,” says Dallen.

Dallen points to the Tasmanian devil as an example of a species that became isolated on a large island after mainland populations became extinct, leading to reduced genetic diversity. This in turn affects the immune system, Dallen says, which puts the species at greater risk of population decline when faced with new pathogens, such as the facial tumour disease that attacks Tasmanian devils.

“Natural selection appears to have been effective in eliminating potentially lethal mutations, but other, less severe mutations gradually increased,” they said. Adrian Lister At the Natural History Museum, London.

“We’re not sure whether this led to eventual extinction, but it’s possible that, combined with environmental changes, it did,” Lister said. “There are lessons here for monitoring the genetic health of endangered species today.”

The exact cause of the mammoths’ extinction is unknown, but interestingly, Wrangel Island contained freshwater lakes and rivers, which suggests that the mammoths may have been able to survive longer than similarly isolated groups that became extinct 5,600 years ago due to drought.

“Diseases, short-term weather events, tundra fires — all of these are thought to be random events,” Dallen says. “Because they’re random, they’re not inevitable. So if they hadn’t happened, the mammoths might have survived to this day, assuming humans hadn’t killed them when they arrived on Wrangel Island.”

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Source: www.newscientist.com