Evolution in Action

From Science Now:

Moths Block Bats' Sonar

A hungry bat screeches out ultrasonic waves and listens as they echo off surrounding objects. One of those echoes sounds an awful lot like a tasty moth, so it swoops in for the kill--but grabs only air. Thwarted again by the tiger moth Bertholdia trigona. New research explains the clever defense; the moth emits ultrasonic clicks that throw off bats' sonarlike echolocation, like jamming a radio signal. It's the first time this type of acoustic interference has been demonstrated in the natural world.