Man may have caused prehistoric extinction
U.S. and British scientists say they've determined prehistoric horses in Alaska may have become extinct due to hunting by man, rather than climate change.
The discovery by Andrew Solow of Woods Hole Oceanographic Institute in Massachusetts; David Roberts of the Royal Botanic Garden; and Karen Robbirt of the University of East Anglia in Norwich, England, is published this week in the Proceedings of the National Academy of Sciences.
The previously accepted view has been that wild horses became extinct long before the extinction of mammoths and the arrival of humans from Asia -- eliminating the possibility they were over-hunted by man. One theory had been that a period of climate cooling caused their extinction.
However, the researchers say uncertainties in dating fossil remains and the incompleteness of fossil records means the survival of the horses beyond the arrival of humans cannot be ruled out.
Copyright 2006 by United Press International
