Scientists are baffled by the mysterious 'thrum' heard for miles from humpback whales, a sound that has been mistaken for machinery or thunder. This peculiar noise, produced by the largest animals on Earth, has now been officially traced to the whales by researchers in Alaska. The discovery, made by biologist Fred Sharpe and his team, reveals a previously unknown sound that can travel at least five miles through the air. The deep thrum, which changes character with distance, has been named a 'low-pitched raspberry' close to the whale and 'more mechanical' from further away, resembling an elephant rumble, distant thunder, or machinery.
The source of the sound remains a mystery, with theories ranging from a self-soothing sigh to a mechanical function like a sneeze. Sharpe's team suspects that the thrums are generated by fatty plugs inside the whales' nasal passages, which act as a seal against seawater when they dive. As the whales return to the surface and exhale with force, these plugs begin to vibrate like pistons, producing the sound. This discovery is particularly intriguing given the whales' weight of over 40 tonnes.
The study, presented at the Astrobiology Science Conference, highlights the tendency of humans to overlook or misidentify signals that do not match their expectations. Sharpe draws a parallel between the whales' conspicuous sounds and the potential for cosmic signals to fall under the radar. The research also has practical implications, as whale sounds detectable from shore could be used to track the animals and avoid collisions with ships. Additionally, the cataloging of various humpback vocalizations, such as 'pizzle', 'chuff', 'boil', 'howl', and 'hoot', opens up new avenues for understanding whale behavior and communication.
The presentation at an astrobiology conference raises philosophical questions about the search for extraterrestrial life and the potential for misinterpreting signals from distant civilizations. Sharpe's work emphasizes the importance of remaining open-minded and attentive to unexpected phenomena, whether they originate from our own planet or beyond.
