Natural Selection
and the “rare enemy effect”
Earthworms
• #1 enemy is the mole
• A mole can eat its weight in worms in a
day
• A worm knows a mole is coming by
“hearing” its feet thumping
Other organisms eat worms
• Sea Gulls perform “foot paddling
behavior”
• Brings worms to the surface
• Wood turtles stomp, brings up worms
• BUT
• Turtles and seagulls do not eat as many
worms as moles, so worms behavior
has not changed.
Humans can worm grunt
• Apalachicola Forest
• Drive a stake into the ground in the
forest
• Rub top with a piece of steel called a
rooping iron
• Video clip: Worm grunting Sopchoppy
Florida
• Video Clip: Worm grunting: Science
behind it