The discovery of 2,000-year-old bison bones in Illinois has contradicted theories that bison were more recent arrivals in the state.
The bones of the American bison were discovered along the Illinois River south of Peoria near Lewistown, the Springfield (Ill.) State Journal-Register reported Tuesday.
As many as 60 million bison -- often inaccurately referred to as buffalo -- roamed North America before being hunted to extinction during the 19th century.
In Illinois, bison were thought to have arrived fairly recently, although the large mammals were present west of the Mississippi River as long ago as 10,000 years, scientists told the newspaper said.
Archaeologists had believed bison arrived in Illinois during the mid 1400s and were extinct in the state by the early 1800s.
But the recent discovery suggests American bison were present on the central Illinois prairies between 265 B.C. and 365 B.C. -- about 1,700 years earlier than believed.
Scientists at the Illinois State Museum in Springfield told the newspaper the discovery is puzzling, especially because no bone tools or scraps of bison have been found in American Indian refuse pits dated before the 1400s.
Copyright 2005 by United Press International
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