In The Elephant's Secret Sense, the internationally renowned field scientist Caitlin O'Connell tells the fascinating story of her unexpected discovery of a previously unknown mode of elephant communication. One day, while observing elephants at a waterhole in Namibia, O'Connell saw the matriarch suddenly turn, flatten her ears, and lift a leg off the ground. Several other females then turned to face the same direction, and soon another elephant appeared. Could elephants feel vibrations through the ground, literally 'listening' with their feet?