All About the Bass: How Baleen Whales Hear Very Low Frequencies

Baleen whales, the largest creatures on Earth, can send extremely low-frequency underwater calls to one another. If the sound waves are short — that is, shorter than the whale's body — the sound's pressure waves can travel through the whale's soft tissue before reaching the tympanoperiotic complex (TPC), which holds the whale's rigid ear bones on its skull. But if the sound waves are longer than the whale's body, they can vibrate its skull in a process known as bone conduction. These longer wavelengths can be amplified, or louder, when they vibrate the skull, the researchers said.