If you were asked to name an animal that has greatly impacted the economic growth of the North American nations, would beavers come to mind? If not, they definitely should. Thanks to ground-penetrating radar readings from satellites, scientists have discovered that beaver dams—once abundant throughout North America—were instrumental in the subterranean sediment buildups that comprise this continent. 

In the December 30, 2011 episode of Science News Flash I discuss not only these findings but also beavers’ substantial influence on Canada and America’s economic beginnings and on wetland ecosystems. Listen to find out why beaver populations are worth preserving.

• “Beavers Helped Build America’s Ground”