Navigation Links
Cichlid fish: How does the swim bladder affect hearing?

"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. 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.


Contact: Friedrich Ladich
University of Vienna

Related biology news :

1. The EU underpays Madagascar for access to fish: UBC research
2. Gallbladder shown as potential stem cell source for regenerative liver and metabolic disease
3. Dung beetle diversity affects Florida livestock producers
4. BPA could affect reproductive capabilities, cause infection of the uterus
5. Life expectancy may affect when you get married, divorced, have kids: Queens University study
6. Loss of predators in Northern Hemisphere affecting ecosystem health
7. Genetically modified corn affects its symbiotic relationship with non-target soil organisms
8. Anti-HIV drug use during pregnancy does not affect infant size, birth weight
9. Immune-response genes affecting breast tumor eradication
10. Dartmouth researchers are learning how exercise affects the brain
11. Socioeconomics may affect toddlers exposure to flame retardants
Post Your Comments:
Related Image:
Cichlid fish: How does the swim bladder affect hearing?
(Date:10/27/2015)... , Oct. 27, 2015 Synaptics Inc. (NASDAQ: ... today announced that Google has adopted the Synaptics ® ... controller solutions to power its newest flagship smartphones, the ... Huawei. --> --> ... Google to provide strategic collaboration in the joint development ...
(Date:10/26/2015)... LAS VEGAS , Oct. 26, 2015 ... an innovator in modern authentication and a founding member ... launch of its latest version of the Nok Nok™ ... to use standards-based authentication that supports existing and emerging ... Suite is ideal for organizations deploying customer-facing applications that ...
(Date:10/23/2015)... DUBLIN , Oct. 23, 2015 Research ... of the "Global Voice Recognition Biometrics Market 2015-2019" ... --> --> The global voice recognition ... during 2014-2019. --> ... 2015-2019, has been prepared based on an in-depth market ...
Breaking Biology News(10 mins):
(Date:11/26/2015)... MUMBAI , November 26, 2015 ... --> Accutest Research ... accredited Contract Research Organization (CRO), has ... Chase Cancer Center - Temple Health ... ,     (Photo: ) ...
(Date:11/25/2015)... BRUSSELS , November 25, 2015 ... in cat and human plaque and pave the way for ... health problems in cats     ... the most commonly diagnosed health problems in cats, yet relatively ... until now. Two collaborative studies have been conducted by researchers ...
(Date:11/25/2015)... Orexigen® Therapeutics, Inc. (Nasdaq: OREX ) ... chat discussion at the Piper Jaffray 27th Annual Healthcare ... discussion is scheduled for Wednesday, December 2, at 8:00 ... replay will be available for 14 days after the ... NormartVP, Corporate Communications and Business Development , BrewLife(858) 875-8629 ...
(Date:11/24/2015)... Calif. , Nov. 24, 2015 Cepheid ... will be speaking at the following conference, and invited ... New York, NY      Tuesday, December 1, 2015 ... New York, NY      Tuesday, December 1, 2015 ... Jaffray Healthcare Conference, New York, NY ...
Breaking Biology Technology: