For over 50 million years, bats and moths have been engaged in an evolutionary arms race: bats evolving new tricks to catch moths, and moths developing counter-measures to escape bats. William Conner, a biologist at Wake Forest University, studies this interaction by filming bat attacks. He and his colleagues report on a new weapon in the moth arsenal: the tiger moth's ability to make sounds that interfere with a bat's ability to echolocate its prey.