Surprisingly the animal with the best hearing is one that has no obvious ears! The greater wax moth, which lays its eggs in honeybee hives around the globe, is said to have the best hearing of any animal on Earth.
This little, silvery grey moth hears using a pair of simple devices called tympanal organs. These are not ears as most people think of them, with fur and skin and flappy bits of cartilage. Instead, they are thin membranes stretched across air-filled chambers, located on either side of the moth’s thorax.
The membranes vibrate in response to sound, sending signals along the auditory nerve to the brain where they are processed. Laboratory studies, which have recorded electrical activity from the auditory nerve, have shown that the moth can detect frequencies of up to 300kHz. For context, humans can hear up to 20kHz, dolphins up to 150kHz and bats up to around 210kHz.
The moth’s impressive hearing range is thought to have evolved in response to pressure from its winged, fly-by-night predators: bats. Over time, the moths developed the ability to detect the high- frequency calls that bats make as they echolocate their prey. Their excellent hearing helps to prevent them from being eaten.
