Les Jones

Environment > Climate Change Killed Mammoths?

"Climate, not humans, said to have killed off mammoths". Darned SUV-driving cavemen.

One hypothesis suggested a virulent disease was responsible for the extinctions. Another theory was that by killing grazing animals, humans triggered changes in vegetation that resulted in the mass deaths.

The Blitzkrieg, or overkill theory, said human hunters devastated most large mammal species and drove some to extinction.

"But contrary to that theory, my dates show numbers of bison and wapiti (elk) were expanding both before and during human colonisation," Guthrie explained.

His radiocarbon research, reported in the journal Nature, shows there was a 1,000-year different between the demise of the wild horse and the woolly mammoth which Guthrie said is inconsistent with other theories.

Instead, he suggests climate shifts transformed the dry, arid and cold region. The wetter, warmer summers led to changes in vegetation to which mammoths and wild horses could not adapt.