Mystery 'random event' killed off Earth's last woolly mammoths in Siberia, study claims

 The planet's last surviving mammoth population was killed by a random and sudden mystery event, a new study has revealed.

The population, isolated from the rest of the world for 6,000 years on Wrangel Island in what is now extreme northern Russia, was previously believed to have been slowly wiped out by genetic inbreeding.

But a new study has found that the population — which grew from at most eight individuals to 300 before its demise 4,000 years ago — did not go extinct for genetic reasons. This leaves an even bigger mystery as to what actually happened. The researchers published their findings June 27 in the journal Cell.

"We can now confidently reject the idea that the population was simply too small and that they were doomed to go extinct for genetic reasons," study senior author Love Dalén, an evolutionary geneticist at the Centre for Palaeogenetics in Stockholm, said in a statement. "This means it was probably just some random event that killed them off, and if that random event hadn't happened, then we would still have mammoths today."

From about 300,000 to 10,000 years ago, woolly mammoths roamed the frigid plains of Europe, Asia and North America. As the ice across these northern regions melted, the Arctic tundra that the giant pachyderms relied on for food disappeared. This caused the mammoths' range to shrink until they eventually disappeared.

But sometime during this timeframe, a small group of mammoths crossed the ice on the northwest coast of Siberia and began to inhabit Wrangel Island, becoming cut off from the population on the mainland once the ice bridge disappeared around 10,000 years ago. Secluded on the frozen island, the mammoths there survived for an additional 6,000 years.

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