Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Fish researcher demonstrates first 'non-visual feeding' by African cichlids

15.04.2009
Lateral line sensory system detects vibrations from unseen prey

Most fish rely primarily on their vision to find prey to feed upon, but a University of Rhode Island biologist and her colleagues have demonstrated that a group of African cichlids feeds by using its lateral line sensory system to detect minute vibrations made by prey hidden in the sediments.

The lateral line system is composed of a canal embedded in the scales along the side of the body of a fish, around its eyes and on its lower jaw, which contain small groups of sensory hair cells that respond to water flow. The lateral line system aids some fish in swimming upstream, navigation around obstacles, and the detection of predators and prey.

According to Jacqueline Webb, a URI professor of biology, cichlids in the genus Aulonocara, which only live in Lake Malawi, have widened lateral line canals that are highly sensitive to vibrations and water flows. They feed by gliding through the water with their chin close to the sand like a metal detector, seeking out twitching arthropods and other unseen prey items.

There are about 16 species of Aulonocara cichlids in Lake Malawi, all of which feed in the sand.

"These cichlids join a short list of fish that have been demonstrated to use their lateral line system to feed," said Webb. "Since most of the fish with widened lateral line canals are found in the deep sea, it's difficult to study them. These cichlids can now be used as a model system for studying widened canals, and we can apply what we learn from them to the fish in the deep sea."

Webb analyzed video of the swimming behavior of the fish in response to live and dead brine shrimp located on the surface of the sandy substrate in a tank. She compared the fishes' ability to detect prey under light and dark conditions, and looked at their ability to detect prey when the lateral line system was chemically "deactivated."

She found that the fish were able to find live prey easily, even in darkness, but not without a healthy lateral line system.

Her discovery opens the door to the study of the convergent evolution of wide canals and raises the question of whether fish that feed non-visually have an ecological advantage over visual-only feeders. Webb was recently awarded a $334,000 grant from the National Science Foundation to study the development and behavioral role of wide lateral lines.

"We also hope that this work will allow us to determine whether the sensory biology of a species can be used to predict its ecological success," she said, "especially in environments where the water quality is poor or where there is increased turbidity. Do these fish have an advantage in water where it is difficult to see well?"

To examine these questions, Webb will use microCT imaging to create a three-dimensional reconstruction of the skulls of cichlids, while also developing what she calls a "chin tickler" – an artificial stimulation delivery system – to standardize the stimulation provided from beneath the sand to the cichlid test subjects.

Todd McLeish | EurekAlert!
Further information:
http://www.uri.edu

More articles from Life Sciences:

nachricht Symbiotic bacteria: from hitchhiker to beetle bodyguard
28.04.2017 | Johannes Gutenberg-Universität Mainz

nachricht Nose2Brain – Better Therapy for Multiple Sclerosis
28.04.2017 | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>