Barren circles dot the dry grasslands across about 1,500 miles of the Namib Desert stretching down the southwestern coast of Africa, emerging, growing, shrinking, and disappearing in lifetimes of 30 to 60 years. The empty patches are accentuated by a rim of particularly tall grasses that ring the circles, which range from 6 feet to 115 feet wide. The fairy circles, as the strange bare soil spots are called, have long puzzled scientists. Although they look a bit like imprints left by massive raindrops, impacting meteors, or as legend would have it, the feet of gods, researchers suspect the pattern may form as a result of a more systematic natural process. But just what that process might be has been the subject of much debate.
http://www.csmonitor.com/Science/2017/0118/What-is-causing-Namibia-s-mysterious-fairy-circles
