[CLIP: Audio of bat calls]Hopkin: Bats use echolocation to hunt for their meals, and moths are often on the menu. He started out by bombarding bits of moth wings with sound and seeing what bounced back. Neil: We discovered that moth scales actually resonate in response to being hit with ultrasound. And they resonate at frequencies that pretty much perfectly match the frequencies that bats use for echolocation. Neil: So we don’t actually know how effective these scales are at protecting moths in the real world.