'Las Vegas of Ants' Visible on Google Earth

Not far from the Grand Canyon, near a landmark called Vulcan's Throne, the ground is dotted with strange, barren circles, visible from orbit. Physicist Amelia Carolina Sparavigna, a specialist in image processing and satellite imagery analysis at the Polytechnic University of Turin in Italy, noticed the bizarre polka- dot features while studying the dimensions of the Grand Canyon rim in Google Earth. In a valley near the cinder cone volcano Vulcan's Throne, on the canyon's North Rim, Sparavigna