Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Cichlid fish: How does the swim bladder affect hearing?

09.08.2012
"Sound vibrations are transmitted to the inner ear via anterior extensions of the swim bladder or via bony ossicles", the biologist Tanja Schulz-Mirbach explains how swim bladders may serve for hearing.

The hearing sensitivity improves considerably in this way. The anterior part of the swim bladder functions in specialized fish species similar to an ear drum. Up to now the effects of the different swim bladder morphologies have not been investigated in detail in cichlid fishes.


Steatocranus tinanti has a tiny reduced swim bladder. Credit: Friedrich Ladich

The behavioural biologists of the University of Vienna Tanja Schulz-Mirbach and Friedrich Ladich as well as Brian Metscher from the Department of Theoretical Biology of the University of Vienna studied the relationship between the shape of the swim bladder and its function. "These fish are perfect for such an investigation because this fish family possesses a large variety of swim bladders ranging from tiny reduced ones to large highly specialized swim bladders with extensions up to the inner ear", the bioacoustician Tanja Schulz-Mirbach explains.

Different swim bladders

Currently we know approximately 1,300 species of cichlid fishes, which live in various habitats."Using microtomographic methods in cooperation with Brian Metscher we could reconstruct swim bladder specializations in detail", Tanja Schulz-Mirbach says. Some cichlid species such as the bottom-living Steatocranus tinanti inhabit fast flowing waters in the Congo river basin and their swim bladders are widely reduced. Cichlids which live in rather calm waters possess large bladders which either lack a connection to the inner ear such as the jewel cichlid Hemichromis guttatus or which possess anterior extensions bringing the swim bladder close to the inner ears. The Malagasy species Paratilapia polleni has simple tube-like swim bladder extensions whereas the Indian cichlid Etroplus maculatus has more complex extensions consisting of a gas-filled tube and a tissue pad which touches the inner ear.

Size matters

Biologists in the bioacoustic lab of Friedrich Ladich measured hearing by recording acoustically evoked potentials (similar to EEGs) from the head of animals non-invasively. "We could show that species having specialized swim bladders detect higher sound frequencies and lower sound levels than species having reduced swim bladders", Schulz-Mirbach explains. However, the jewel cichlid which has a large swim bladder but no connection to the inner ear is also able to detect frequencies up to 3 kHz but only at higher sound levels. "This means that the presence of anterior swim bladder extensions results in better hearing but the size of the swim bladder is also important", explains Schulz-Mirbach says. She will continue to investigate the importance of the habitat noise on the development of hearing and if swim bladder specializations affect inner ear anatomy.

Publication:

"Relationship between swim bladder morphology and hearing abilities. A case study on Asian and African cichlids": Tanja Schulz-Mirbach, Brian Metscher, Friedrich Ladich (PLoS ONE 2012) DOI: http://dx.plos.org/10.1371/journal.pone.0042292

Contacts:

Dr. Friedrich Ladich
Department of Behavioural Biology
1090 Vienna, Althanstraße 14 (UZA I)
T +43-1-4277-542 27
friedrich.ladich@univie.ac.at
Dr. Tanja Schulz-Mirbach
Department of Behavioural Biology
1090 Vienna, Althanstraße 14 (UZA I)
T +43-1-4277-544 30
tanja.schulz-mirbach@univie.ac.at

Friedrich Ladich | EurekAlert!
Further information:
http://www.univie.ac.at

More articles from Life Sciences:

nachricht New risk factors for anxiety disorders
24.02.2017 | Julius-Maximilians-Universität Würzburg

nachricht Stingless bees have their nests protected by soldiers
24.02.2017 | Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Safe glide at total engine failure with ELA-inside

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded after a glide flight with an Airbus A320 in ditching on the Hudson River. All 155 people on board were saved.

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded...

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Safe glide at total engine failure with ELA-inside

27.02.2017 | Information Technology

Fraunhofer IFAM expands its R&D work on Coatings for protection against corrosion and marine growth

27.02.2017 | Materials Sciences

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>