Mammoth-killing comet circa 13,000 BCE questioned
BBC 1/29/09: “Mammoth-killing comet questionedâ€
“A study of wildfires after the last ice age has cast doubt on the theory that a giant comet impact wiped out woolly mammoths and prehistoric humans.
Analysis of charcoal and pollen records from around 13,000 years ago showed no evidence of continental-scale fires the cometary impact theory suggests.
However, the results showed increased fires after periods of climate change.
The research is published in the Proceedings of the National Academy of Sciences (PNAS).
The cometary impact hypothesis holds that an enormous comet slammed into or exploded over North America in the Younger Dryas period some 12,900 years ago.â€
More:
http://news.bbc.co.uk/2/low/science/nature/7854348.stm