Elephants 'phone' friends with rumbles

Researchers at Disney's Animal Kingdom outfitted elephants with a GPS system and recorder attached to a collar made out of fire hose to monitor the rumblings of the animals. The elephants emit the rumblings to communicate with other elephants far away. ... Human friends and relatives keep tabs on their loved ones by phone when they're apart, and now new research shows elephants do nearly the same thing with rumble vocalizations that can transmit over one and a half miles.

The finding helps to explain how elephants almost always find their way back to their herd, even after they wander far off.

Elephants can see and smell their fellow herd members over long distances too, but visual obstructions, such as rocks, trees and even other big animals, can block their views, while wind changes and smells can compromise odor detection. ... Leighty, a behavioral ecologist at Disney's Animal Kingdom in Florida, and her team conducted the first systematic study of spontaneously produced elephant rumble vocalizations. These are typically infrasonic calls, with frequencies between 13 and 35 Hz, which fall outside the range of human hearing. - msnbc