LARAMIE, Wyo., July 6 -- The University of Wyoming issued the following news release:

Early humans in North and South America relied heavily on hunting of large mammals, including mammoths and giant ground sloths, for food and sustenance, according to newly published research by a team including two University of Wyoming archaeologists.

The findings by UW Professor Todd Surovell, Professor Emeritus Robert Kelly and colleagues from other institutions are the latest development in a long-running debate over the behaviors and movements of early Americans before the extinction of large, plant-eating animals -- such as mammoths, other elephant-like creatures, giant ground sloths and large camels -- between 11,000 and 13,000 years ago.

The new...