http://news.bbc.co.uk/2/hi/science/nature/7130014.stm
"Startling evidence has been found which shows mammoth and other great beasts from the last ice age were blasted with material that came from space. v Eight tusks dating to some 35,000 years ago all show signs of having being peppered with meteorite fragments.
The ancient remains come from Alaska, but researchers also have a Siberian bison skull with the same pockmarks.
The scientists released details of the discovery at a meeting of the American Geophysical Union in San Francisco, US.
They painted a picture of a calamitous event over North America that may have severely knocked back the populations of some species." snip.... (More at link!)
Caption "The embedded particles have a high iron-nickel content"
But having gone out and tested the hypothesis of tusk impacts, and having apparently uncovered such items - the team was then astonished to find the animal remains were about 20,000 years older than had been anticipated.
The researchers are now considering a number of possibilities - one that could even tie the older remains to the younger event.
Tusk particle (Firestone et al) The embedded particles have a high iron-nickel content "People who collect these items today in Siberia and Alaska frequently find the tusks sticking out of the permafrost or eroding out of a riverbank," explained Mr West.
"Maybe, these were tusks from dead animals that were just exposed on the surface, so when this thing blew up in the atmosphere, it would have peppered them. The date could really be anywhere from 13,000 to 35-40,000 years ago."
