London, November 23 (ANI): In a new research, scientists have determined that sophisticated hunters cannot be blamed for driving mammoths to extinction, as these creatures and other giant ice-age mammals faced extinction 2,000 years before deadly speartips were invented.
According to a report in the Guardian, the research team was led by Jacquelyn Gill, a PhD student at the University of Wisconsin, Madison, US.
The prehistoric mammoths began their precipitous decline nearly 2,000 years before our ancestors turned stone fragments into sophisticated spearpoints at the end of the last ice age.
The animals, which included mammoths, elephant-sized mastodons and beavers the size of black bears, were probably picked off by more inept hunters who only much later developed specialized weapons when their prize catches became scarce.
"Some people thought humans arrived and decimated the populations of these animals in a few hundred years, but what we've found is not consistent with that rapid 'blitzkrieg' overkill of large animals," said Gill.
Archaeological evidence shows that humans developed advanced spearheads around 13,000 years ago.
The Clovis people of North America crafted speartips with deep grooves that made wounds bleed freely.
With these, hunters did not have to kill their prey on the spot, but could wait for the beasts to bleed to death.
The rise of the Clovis culture was thought to coincide with the demise of the woolly mammoth and other slow-moving giants on the continent, leading many researchers to suspect the animals died at the ends of the hunters' spears.
Gill's team rules this out by putting a more accurate date on the decline and fall of woolly mammoths and more than 30 other large mammals that dominated the landscape as the ice sheets retreated from North America.
To date the animals' slide to extinction, the scientists examined sediment cores from a lake in Indiana.
The deepest sediments were laid down in the distant past, while more recent sediments were nearer the surface.
Specifically, the scientists measured levels of a fungus that is known to thrive in the excrement of giant herbivorous mammals and nowhere else.
They reasoned that more fungal spores meant more dung, which in turn reflected a larger population of roaming mammals.
The researchers describe how the amount of mammal dung started to fall around 14,800 years ago, long before advanced spearheads became commonplace.
The animals had been almost completely wiped out a thousand years later.
"We know there were people who pre-dated the Clovis culture who were butchering mammoths in the area. What we're suggesting is the declines happened before the Clovis toolkit was adopted. These earlier people had tools, but they probably weren't as sophisticated," said Gill. (ANI)