Worm Grunting Mystery Solved

The phenomenon known as worm grunting has been solved.  Fishermen in some areas of the U.S. have long made use of worm grunting to gather up earthworms as bait.  They go about this by driving a stake into the soil and rubbing it, transferring vibrations into the ground.  The earthworms appear 'magically' on the surface as if in answer to the vibrations call. (For you who have read the Dune series, you will recall this is how the giant sandworms were summoned.)

Dr. Ken Catania of Vanderbuilt University was intriqued by the phenomenon and conducted experiments to solve the mystery.

The worms are not answering a call, they are fleeing from the sound that moles make as they dig through the soil.  Moles eat earthworms.