Home / World / The rat, thought to have been extinct for over 150 years, lives on an island off Western Australia.

The rat, thought to have been extinct for over 150 years, lives on an island off Western Australia.

Scientists compared DNA samples from eight extinct Australian rodents with 42 living relatives and found that the extinct Gould’s mouse was “indistinguishable” from the Shark Bay mouse.

Researchers are studying the deterioration of the country’s native species since the arrival of Europeans in Australia in 1788.

The rat, still known by the common name “djoongari” or “shark bay rat”, was once found across the country. from southwest Western Australia to New South Wales. But it was last seen in 1857, researchers say. introduction of invasive species Agricultural land purges and new diseases have destroyed native species. It added that climate change and poor fire management also affect population size.

The remaining population of djoongari is located on a 42-square-kilometer (1

6.2-square-mile) island in Shark Bay, Bernier Island. The small population alone is not sufficient for survival, researchers say. Therefore, the rats were taken to two other islands to create new populations.

Emily Roycroft, an evolutionary biologist at Australian National, said: “The resurrection of this species has brought great news in the face of an overly high extinction rate of native rodents, which account for 41% of animal extinctions. mammals in Australia since European colonization in 1788,” the university said in a statement.

“It’s exciting that Gold’s rat is still around. But its disappearance from the mainland saw the species shift from predominantly across Australia. how fast only surviving on an offshore island in Western Australia. causing the population to collapse in large numbers.

The team also looked at seven other extinct native species, which found high genetic diversity immediately before extinction. Showing how widespread their population was before Europeans arrived.

“This shows that genetic diversity is not a guarantee of extinction,” Roycroft warned.

The sixth mass extinction is happening sooner than expected.  Scientists say it's our fault.
More than 80% of Australian mammals are endemic. as a result of Australia’s prolonged separation from other continents. But the country has what researchers described in a 2015 report as an “extinct extinction rate.” A study published in 2019 found that Australia was home to 6-10% of the recognized post-1500 extinctions worldwide.

Roycroft said the extinction of the seven native animals happened “very early”.

“They should be common. with a large population before the arrival of the Europeans But the introduction of feral cats, foxes and other invasive species Agricultural land purges and new diseases have completely destroyed native species,” she said.

Humans have exterminated hundreds of species. and pushing many more species to the brink of extinction through wildlife trade, pollution, habitat loss. and the use of toxins The world’s sixth mass extinction is happening now. Much faster than expected And the extinction rate of species has accelerated over the past several decades. Scientists warn
The research will be published in the journal PNAS next month.

CNN’s Ivana Kottasová contributed to the report.

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