Danionella cerebrum is one of the smallest fish in the world, measuring only 1.27cm as adults. They are primarily found in shallow waters off the coast of Myanmar. However, this fish has the remarkable ability to produce sounds louder than 140 decibels (dB).
140dB is the threshold for causing hearing damage in humans, meaning this sound is louder than a fire engine siren or a plane taking off (130dB).
Ralf Britz, the lead researcher, said: “This volume is comparable to the noise humans hear when a plane takes off from a distance of 100m, which is quite astonishing for such a small-sized animal.”
Typically, larger animals tend to produce louder sounds than smaller ones, with elephants being able to generate sounds up to 125 decibels using their trunks. However, nature is not short of surprises. Some small animals can produce extremely loud sounds relative to their size, including pistol shrimp, which use their claws to create snapping sounds with a volume of up to 250 decibels.
There are also some fish species that produce unusually loud sounds, such as the male Midshipman fish, which can emit mating calls up to 130 decibels. However, Danionella cerebrum appears to be the most unique species among the fish.
In history, neuroscientists have been particularly interested in the Danionella cerebrum fish because it has the smallest brain known among any vertebrate species on the planet.
This transparent fish, with no skull, allows researchers to easily observe and access its brain tissue. While studying the fish’s brain in a laboratory setting, a group of researchers in Germany recently decided to investigate the noise emitted from the tank of these organisms.
After conducting experiments, the scientists discovered that this fish produces the noisy sounds through its bubbles. And only the male fish can generate such loud sounds.
Although the source of the sounds from the Danionella cerebrum fish is known, the researchers still do not know exactly why they do it. However, they have some hypotheses. It is possible that the fish produces sounds to locate each other in turbid water. Or, perhaps, because only the male emits the sounds, it serves to attract mating partners or warn other males to stay away.