The vibrations are felt because they travel to the body of the receiving frog and land in the bones of the inner ear. These bones also receive sounds.
The vibrations differ according to the message. The receiver is able to determine how big the sender is and what their motivation and status is.
It has been known that frogs sometimes vibrate when they are in danger. It was thought that the frog does this to look bigger, but now it seems that this is not the case.
Vibrations may be a remarkably effective means of communication. The frogs do not have to see each other and the vibrations can travel. The frogs are able to sense the vibrations from up to two metres.
Communication via vibrations has up till now only been seen in insects. It seems that this effective means of communication has been overlooked for years by the researchers.