How can an elephant hear with its feet?

Have you ever rested your hand on a table while someone knocked on the other end? You can feel each knock in your fingers, even with your eyes closed. Your hand catches the knock through the wood.

Elephants do something like that, but with the whole ground under them. People say an elephant can hear with its feet. So how can an elephant hear with its feet?

It starts when one elephant calls to its family with a deep, low rumble. The rumble is so low that you would hardly hear it at all. As the elephant rumbles, its voice goes into the air and down into the ground too.

In the ground, the rumble becomes a vibration, which means a quick little shaking back and forth. The vibration spreads through the earth, the way a ripple spreads across a pond. It can travel a long way, past trees and over hills.

Far away, another elephant stands on the grass. Under each big foot lies a thick, soft pad, packed with spots that feel the smallest shake. When the vibration arrives, those spots feel it, just as your fingers felt the knock.

To listen well, the elephant leans forward and presses its front feet into the ground. Pressing down helps the feet catch even a faint vibration. Now the shake is inside the elephant's foot. Where do you think it goes next?

The shake climbs up through the elephant's leg bones, all the way to its head. Hard bones carry a vibration well, like the table carried the knock to your hand.

Up in the head, the shaking reaches the elephant's ear, deep inside. The ear picks it up, and the elephant hears its family member calling from far away. Its feet and its ears work together as one.

One word to remember: vibration. When an elephant rumbles, it sends a vibration through the ground, and another elephant feels it with its feet and hears it when the shake travels up its bones to its ears.

Sleep well, and may the quiet ground beneath you feel soft and still tonight.