Stanford researcher Caitlin O'Connell discovered that elephants can hear with their feet:
She was supposed to find ways to keep elephants out of farmers' fields. While observing them, she started to notice certain odd things.
"Normally, they would hold their big ears out like a parabola and scan back and forth," O'Connell said. "But to detect distant noise and vocalizations, they'd freeze and lean forward and put weight on their front legs. Sometimes they'd even lift up a front foot. All of them would do this at the same time -- it was too coordinated to be a coincidence."
The behavior sometimes occurred when another herd approached or a ranger drove by in his vehicle.
"On a most fundamental level, the research is showing elephants have a whole modality for communicating that we haven't thought about," O'Connell said.