Woolly mammoths are extinct due to climate change, human hunters are not

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CAMBRIDGE, England – The disappearance of the woolly mammoth has been debated for centuries, with prehistoric hunters being the main suspects. However, according to new research, the giant herbivore has come to an end because of climate change, not humans.

Scientists say global warming happened so quickly around the time that vegetation disappeared and woolly mammoths starved to death. Analysis of plant and animal remains, including urine, feces and skin cells, now provides the definitive answer.

“Scientists have been arguing for hundreds of years as to why mammoths are extinct. Humans have been blamed because animals have survived millions of years without climate change killing them before. But when they lived alongside humans, they didn’t last long and we were accused of hunting them to death, ”says study co-author Eske Willerslev of the University of Cambridge in England and the corresponding author of the study, in a press release.

Unearthing Arctic History

Ancient soil samples have been painstakingly collected over 20 years from arctic sites where mammoth bones have been found. “We were finally able to prove that it was not just climate change that was the problem, but the speed of it that was the last nail in the coffin. They weren’t able to adapt quickly enough when the landscape changed dramatically and their food became scarce, ”says Willerslev.

A mammoth tusk on the bank of the Logata River. (Credit: Johanna Anjar)

Melted icebergs flooded the steppe tundra, wiping out the plants, flowers and small shrubs that supported the mammoths. The animals used their huge tusks, which grew up to 14 feet long, to shovel snow and uproot tough grass. “As the climate warmed, trees and plants in wetlands took over and replaced mammoth grassland habitats,” says Willerslev.

The hairy cousins ​​of today’s elephants lived alongside early humans and were a regular staple of their diet. Their skeletons and huge tusks were used to build shelters and harpoons. The works of art representing them are plastered on the walls of the cave. A 30,000-year-old flute made from mammoth bone is the oldest known musical instrument. But there is little direct evidence that our ancestors actually killed mammoths.

“And we have to remember that there were a lot of animals around that were easier to hunt than a giant woolly mammoth – they could reach the height of a double-decker bus,” adds Willerslev.

Woolly mammoths among the world’s most fascinating creatures

Woolly mammoths and their ancestors are among the most successful creatures to ever roam the Earth. They existed for five million years until they disappeared for good almost 4,000 years ago. Professor Willerslev and his colleagues say the ten-year study finally proves why. It was based on “DNA gun sequencing” which breaks a genome into small fragments to identify organisms. The lab technique was used during the pandemic to track COVID by testing wastewater. It allows experts to recreate ancient genetic profiles without relying on bones or teeth.

Mammoths have evolved and withstood several ice ages. Vast herds thrived, alongside reindeer and woolly rhinos. Despite the cold and the snow, there was plenty of vegetation to keep them alive. Mammoths could travel a distance equivalent to circling the world twice in their lifetime. Fossil records show that they lived on every continent except Australia and South America.

Populations were known to have initially survived the end of the last ice age in small pockets off the coasts of Siberia and Alaska – on Wrangel Island and St. Paul Island. But research found they actually lived longer elsewhere. The two island races were closely related, although geographically separated. The DNA of 1,500 arctic plants has been mapped as part of the project so that meaningful conclusions can be drawn globally.

“The most recent ice age – called the Pleistocene – ended 12,000 years ago when glaciers began to melt and the roaming range of mammoth herds declined. Mammoths were thought to have started to disappear around this time, but we also found that they had survived beyond the Ice Age in different parts of the Arctic and into the Holocene – the time in which we are living now – much longer than scientists thought, ”notes the study’s first author, Dr Yucheng Wang, also of Cambridge.

A selection of sediments collected from sites across the Arctic. (Credit: Yucheng Wang)

“We have zoomed in on the intricate details of environmental DNA and mapped the spread of the population of these mammals and shown how they are getting smaller and smaller and their genetic diversity is getting smaller and smaller as well, which makes their survival even more difficult. When the climate got wetter and the ice started to melt, this resulted in the formation of lakes, rivers and marshes, ”Dr. Wang continues. “The ecosystem has changed and the biomass of the vegetation has decreased and could not have supported the mammoth herds. We have shown that climate change, especially precipitation, directly drives vegetation change – humans have had no impact on them according to our models. “

The mammoths were even present during the construction of the pyramids. Their disappearance is the last great story of natural extinction. Our fascination continues today with Manny, the woolly mammoth, the star of five animated films from the Ice Age. Woolly mammoths could even be “resuscitated” within six years. Harvard geneticists have raised $ 15 million to try to bring them back.

“Nothing is guaranteed with regard to dramatic climate change”

Professor Willerslev said the discovery had implications for the climate crisis the world faces today: “It’s a brutal lesson of history and shows how unpredictable climate change is – once something is lost, there is no turning back. Precipitation was the cause of the extinction of woolly mammoths due to changes in the plants. The change happened so quickly that they couldn’t adapt and evolve to survive.

“This shows that nothing is guaranteed with regard to the impact of dramatic climate change,” he continues. “Early humans would have seen the world change beyond recognition – it could easily happen again and we cannot assume that we will even be there to witness it. The only thing we can predict for sure is that the change will be massive. “

The mammoth was identified as an extinct species of elephant by Georges Cuvier in 1796. It was roughly the same size as modern African elephants. Males reached over 11 feet tall and weighed up to six tons.

This study is published in the journal Nature.

South West News Service writer Mark Waghorn contributed to this report.

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