This Tiny Fish Can Produce Sounds That Are As Loud As A Firecracker

One of the smallest fish in the world can make a sound registering more than 140 decibels – as loud as exploding firecrackers

© Copyright by GrrlScientist | hosted by Forbes | LinkTr.ee

As a lifelong fishkeeper, I’m familiar with noisy fish. Perhaps my favorite noisy aquarium fish are the Synodontis catfishes, which produce a rasping sound resembling a growl that can easily be heard outside their aquarium during territorial disputes.

But now we can add another species to our list of noisy fish: Danionella cerebrum. These tiny freshwater fish are found in turbid low altitude streams on the southern and eastern slopes of the Pegu Ran mountain range in Myanmar. Danionella cerebrum are closely related to — and closely resemble — zebrafish. Their transparency makes it is possible to observe its brain in action and thus, they are prized as a model organism for biomedical research.

As adults, these fish are no more than 12 millimeters long — less that half an inch in length. But despite being tiny, they are mighty: producing sounds in the waters close to its body exceeding 140 decibels — as loud as a firecracker. Considering its diminutive size, this species is probably, gram-for-gram, the loudest fish ever discovered.

Making noises is not uncommon in the animal kingdom. In fact, it’s a popular way to communicate over distances.

“Fishes, on the other hand, are generally considered to be rather quiet members of the animal kingdom,” explains fish researcher Ralf Britz, Head of the Ichthyology Section of the Senckenberg Natural History Collections in Dresden. Dr Britz’s research focuses on the morphology, comparative anatomy and taxonomy of fishes, particularly those occurring in Myanmar.

“However, there are certain fish species that can be surprisingly loud,” Dr Britz pointed out. “For example, the male plainfin midshipman fish attracts its females with an audible vibrato of around 100 hertz and 130 decibels.”

In their study, Dr Britz and collaborators report that these tiny, transparent fish possess a special sound-generating organ that presumably, they use to communicate with others of their kind in turbid waters. The sound is only produced by males of the species.

“We assume that the competition between the males in this visually restrictive environment contributed to the development of the special mechanism for acoustic communication,” Dr Britz proposed.

Observers standing beside, or passing by, the lab’s fish tanks could hear a continuous buzzing sound, and this led to investigations that identified the fish itself as the source of the sound.

“This tiny fish can produce sounds of over 140 decibels at a distance of 10 to 12 millimeters — this is comparable to the noise a human perceives of an airplane during take-off at a distance of 100 meter, and quite unusual for an animal of such diminutive size,” Dr Britz elaborated. “We tried to understand how the fish manages this and what mechanisms are responsible for this achievement.”

To document this phenomenon, Dr Britz collaborated with an international team of scientists led by neuroscientist Benjamin Judkewitz from Charité in Berlin and Verity Cook, a graduate student at Charité. They filmed small groups of 3-4 fish using high-speed video, then slowed down the recordings to observe the mechanism of sound-generation. Because the fish are transparent, the team could watch the living fish as they created sounds.

They discovered that when the fish produce sound, a rib adjacent to their swim bladder, a vital organ that controls buoyancy in fish, is pulled by a specialized muscle into a piece of cartilage with a small indentation. The tension built up in this contraction is rapidly released, rather like snapping a rubber band, causing the rib to strike the swim bladder and generate the distinctive drumming sound.

“This apparatus accelerates the drumming cartilage with a force of over 2,000 g and shoots it against the swim bladder to produce a rapid, loud pulse. These pulses are strung together to produce calls with either bilaterally alternating or unilateral muscle contractions,” Dr Britz explained.

The evolution of this unusual ability to make loud noises likely played a role in the fish’s adaptation to murky waters in Myanmar.

It’s interesting to note that there are a number of other Danionella species in the aquarium trade, which makes one wonder whether they, too, can produce sound and if their mechanism of sound production is the same, or if it differs by species.

“The sounds produced by other Danionella species have not yet been studied in detail; it would be interesting to learn how their mechanism of sound production differs and how these differences relate to evolutionary adaptation. In combination with its lifelong transparency, the genus Danionella offers a unique opportunity to compare the neural mechanisms underlying the sound generation between the different species.”

Source:

Verity A. N. O. Cook, Antonia H. Groneberg, Maximilian Hoffmann, Mykola Kadobianskyi, Johannes Veith, Lisanne Schulze, Jörg Henninger, Ralf Britz, and Benjamin Judkewitz (2024). Ultrafast sound production mechanism in one of the smallest vertebrates, Proceedings of the National Academy of Sciences 121(10):e2314017121 | doi:10.1073/pnas.2314017121 (also includes videos)

Socials: Bluesky | CounterSocial | Gab | LinkedIn | Mastodon Science | Post.News | Spoutible | SubStack | Threads | Tribel | Tumblr | Twitter