The Last Wooly Mammoths Died Isolated and Alone
Genome sequencing shows severe inbreeding contributed to the mammoths’ extinction.
The last of the wooly mammoths likely lived and died on an isolated island.
Researchers recently completed sequencing the wooly mammoth’s genetic code and are using the data to piece together clues as to how the creatures went extinct. By comparing DNA samples from different specimens, scientists determined that the last mammoths likely lived on Wrangel Island, a Russian territory in the Arctic Ocean, according to a new study in Current Biology.
Wooly mammoths were about the same size as modern African elephants, but covered in thick brown hair and enormous tusks. The first appeared about 700,000 years ago in Siberia and spread throughout North America and northern Eurasia. A tooth sample found on Wrangel Island is one of the most recent wooly mammoth remains found to date and is about 4,300 years old.
The island separated from the Russian mainland about 12,000 years ago by rising sea levels, taking a group of mammoths along with it. But by that time, according to the fossil record, mammoth populations were already starting to die off.
“We don’t know why,” Love Dalen, the senior author of the report and an associate professor of biology at the Swedish Museum of Natural History in Stockholm, told Nicholas Bakalar for the New York Times. “Human hunting, changes in the environment, warming of the temperatures. But it happens everywhere — that’s for sure — and at the same time.”
By comparing DNA taken from a 4,300 year-old mammoth tooth found on Wrangel Island with that of a 45,000 year-old soft tissue sample found in northern Siberia, the researchers discovered that there had been two massive die-offs before the last mammoths went extinct. Wooly mammoths had already survived a massive die-off about 300,000 years ago; it took the species around 100,000 years to recover. After the second die-off, about 12,000 years ago, the survivors numbered in the hundreds, according to Reuters. The Wrangel Island mammoths likely survived for about 6,000 years after the mainland mammoths died out. Dalen’s group also found that the Wrangel Island mammoth population’s isolation was severely inbred, which likely contributed to their extinction.
However, there’s an interesting twist to this discovery: because the researchers sequenced the genomes of several individual mammoths, it might be possible to resurrect the species, something ethicists and researchers have been arguing about for a long time now.
But whether or not wooly mammoths roam the Siberian tundra again, spare a thought for the loneliness of those last beasts in the middle of the Arctic.