Scientists discover hedgehogs can hear ultrasound and it could save them from cars

Researchers have discovered that hedgehogs can hear ultrasound, a surprising ability that could help protect them from cars. Since road traffic kills large numbers of hedgehogs, scientists believe ultrasonic repellents might be used to steer them away from danger. The animals ears appear specially adapted for detecting high-frequency sounds. If the idea works, cars could one day emit signals that warn hedgehogs before its too late.