- This small fish with the Latin name Danionella cerebrum, which measures 12 mm, is apparently capable of making sounds that are almost the same as the sound of an orca or killer whale at 140 decibels. The .22 caliber pistol shot is also at this number.
- This amazing finding was reported in the journal of the National Academy of Sciences (PNAS), February 2024, by a number of German researchers, most of whom came from Charité University, Berlin.
- According to them, the facts about the small fish contradict the conventional view that the speed of movement of vertebrate skeletons is limited by muscle action.
- Danionella cerebrum fish have special muscles that are designed to resist fatigue. So that a certain mechanism can produce a shock to the swim bladder with a fast and loud pulse. This is the source of this fish's extraordinary thumping sound.
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| Hear This, The Sound Of A Small Fish That Is The Equivalent Of A Gunshot |
In the underwater world, never underestimate the sound of small fish. Because small fish may make the same or stronger sound than fish that are much larger.
The fish with the Latin name Danionella cerebrum is known to sound more or less the same as an orca or killer whale. Even though orcas are up to 8 meters long, the length of D. cerebrum is less than 12 mm or only the size of an adult human's fingernail.
The whistle of an orca or killer whale is at 140 decibels. The .22 caliber pistol shot is also at this number. Using data presented by Scientific American, sperm whales produce sonar sounds of nearly 240 decibels and are the loudest animals in the water known at the moment.
This amazing finding was reported in the journal of the National Academy of Sciences ( PNAS ), February 2024, by a number of German researchers, most of whom came from Charité University, Berlin. According to them, this fact contradicts the conventional opinion that the speed of movement of the vertebrate skeleton is limited by muscle action. To the layman, that might sound very technical.
However, in simple terms it can be said that the speed of movement of the skeleton or bones in vertebrates depends on muscle strength. Well, different from other vertebrates, the Danionella cerebrum fish has special muscles that are designed to withstand fatigue. So that a certain mechanism can produce a shock to the swim bladder with a fast and loud pulse. This is the source of this fish's extraordinary thumping sound.
However, don't confuse the loudness of a gun in the air with that in water. The loud sound it made in the water was like hitting an impermeable material. Even so, the sound of this fish can still be heard from above the water.
This fish is one of the favorite fish of scientists. The reason is because this species is one of the smallest transparent vertebrates. Even his brain was visible. This helps researchers study the workings of the brain and nerves. Cerebrum itself is Latin for brain.
The story of how this loud fish was discovered is no less interesting. Initially, for research purposes, a number of Danionella cerebrum fish were placed in a tank in the laboratory. As researchers passed the tank, they heard a mysterious sound.
“People walk past fish tanks, and they can hear these sounds, and wonder where they come from,” said Verity ANO Cook, lead author of the report, as quoted by the BBC . “It turns out the sounds came from the fish itself. And it's amazing, because it's so small and (the sound) is so loud.”
At a distance equal to the body length of this fish, the amplitude of the sound produced is around 140 decibels. When measuring at a distance of 1 meter, the amplitude drops to 108 decibels. Even so, this is still equivalent to the noise produced by a bulldozer. Even when humans are next to the tank, it will sound like a repetitive buzzing.
To reach their conclusion, the researchers placed several groups of D. cerebrum fish in aquariums measuring 9 x 6 x 2 cm with at least one male in each group. High-speed video records fish movements at a frame rate of 2000 to 8000 fps, from all sides, up and down, right and left, and front and back. They also use hydrophones to record sounds underwater.
The researchers found that this fish uses special cartilage ( drumming cartilage ), ribs, and fatigue-resistant muscles to produce sound. When the vocal muscles contract, the fifth rib is pulled forward and produces tension on the cartilage. The sudden release of the cartilage causes successive blows to the swim bladder and produces a loud sound.
The researchers suspect that D. cerebrum's ability to produce loud sounds is part of this fish's adaptation to navigation in shallow and murky waters. Apart from that, only male fish produce sound. Possibly, the sounds from male fish also indicate hierarchy. This special fish lives in small rivers along the Bago Yoma mountains, Myanmar.
D cerebrum was scientifically described only in 2021 . Previously this fish species was included in Danionella translucida which is equally transparent. Even under a microscope these two fish look the same. However, using DNA sequencing, it is known that these two fish are different and it is estimated that they separated 15 million years ago.