It is hard to believe, as the scientists discovered that among all fish, the male Danionella cerebrum makes deep and strong sounds that might be as powerful as a gunshot! This tiniest fish, at the width of an adult human fingernail (about 12mm), lives in the streams of Myanmar and has dazzled scientists with its remarkable auditory skills.
The PNAS journal reports that male Danionella cerebrum can produce sounds in the range of 140 decibels, which is the level of an ambulance siren or a jackhammer. This discovery astonishes the experts, as it concerns the fish’s minute dimensions. Historically, fish make noises through the vibrations of their swim bladders, which are gas-filled organs that are critical for the fish to be buoyant.
The Danionella cerebrum’s fast-paced beating remained a mystery until now, which has now been uncovered. The scientists from Charité University in Berlin discovered drumming cartilage, a structured rib, and fatigue-free muscle that make it possible to produce unique sounds. High-speed video recordings unveiled the fish’s method: the cartilage is made from a special muscle that moves a rib adjacent to the swim bladder. Upon release, the rib strikes the swim bladder with the resultant hard drumming sound.
On the other hand, males have harder ribs than females, and the reason why only males create these significant sounds is unknown. Although why they have such remarkable hearing abilities is still unknown, scientists suggest that it may help them navigate in turbid waters or deter enemies. This innovative finding gives us not only an insight into animal behavior but also reveals the fascinating diversity of evolutionary adaptations among species.