Earth, as we know and recognise today, didn’t always look like this. Even though humans dominate a majority of the planet now, other, mightier creatures once roamed free on a planet that looked very different. While animals like dinosaurs are prehistoric and were wiped out from the face of Earth before mammals could evolve, one other mighty animal evidently lived after humans came on to the scene—woolly mammoths. The animal well-adapted to cold climates was very abundant in North America but was suddenly gone. And now scientists believe they know the reason for their disappearance.
They believe it was a sudden cold snap that resulted in the extinction. The cold didn’t just take out woolly mammoths, but a majority of North American megafauna including bear-sized beavers; claims a study published in Nature Communications.
Previously, over-hunting has been cited as one of the extinction causes. Humans have been known to hunt these animals for meat, tusk, fur, and bones. But the paper believes there’s more to the story.
“Extinction is a process — meaning that it unfolds over some span of time,” said author Mathew Stewart from the Max Planck Extreme Events Research Group in Jena. Because of this, they should look at long-term patterns leading to the extinction, he suggests.
They observed that 14,700 years ago, the megafauna was actually growing because of a warming period in the ice age. But around 12,900 years ago, the temperatures began to drop exponentially. The team used radiocarbon dating to estimate population sizes. They discovered that even if overhunting occurred, the populations were already declining due to climate change. The megafauna during the time had gigantic animals; including sloths and armadillo species.
The previously held belief of overhunting is because these animals did not have many natural predators until humans arrived. But can a handful of human hunters wipe out whole species with stone tools?
“'Humans also aren't completely off the hook, as it remains possible that they played a more nuanced role in the megafauna extinctions than simple overkill models suggest,” said Dr Huw Groucutt.
So, in conclusion, the sudden cooling of the planet, aided by hunter-humans, lead to the extinction of this once mighty species—along with others who weren’t even hunted.