Navigation Links
Specialization for underwater hearing by the tympanic middle ear of the turtle

A group of biologists from Denmark and the US led by Jakob Christensen-Dalsgaard, University of Southern Denmark, and Catherine Carr, University of Maryland, have shown that the turtle ear is specialized for underwater hearing. The new discovery is published in Proceedings of the Royal Society B March 21st , Special features of the turtle ear a large, air-filled middle ear and a movable tympanic disk increase its sensitivity for underwater sound. Laser measurements of disk vibrations in response to underwater sound show up to 100-fold larger vibrations of the disk than the surrounding water, most likely because the air volume resonates in an underwater sound field and drives the tympanic disk.

The tympanic middle ear is often seen as an adaptation to hearing in air, but the turtle tympanic ear is an anomaly here, because turtles are generally 100-fold less sensitive than other animals with eardrums, like mammals, birds and reptiles.

However, turtles are amphibious animals, and anatomical and biophysical studies by a group of biologists from Denmark and the US have shown that the ear of the red-eared slider is specialized for underwater rather than airborne sound.

CT scans, laser measurements from the ear under water and auditory evoked responses showed that the turtle ear was more sensitive for underwater than for airborne sound. The sensitivity is caused by the air filled middle ear. Resonance in the air cavity lined by the tympanic disc drives the disc and amplifies its vibrations up to 100 fold under water.

What the turtle is using its sensitive underwater hearing for is unknown. However, the sensitive hearing can be used for prey capture, predator avoidance and navigation under water. An alternative possibility is that turtles communicate by underwater sound. Underwater sound communication is unknown in the red-eared slider, but has recently been described in two other turtle species.


Contact: Jakob Christensen-Dalsgaard
University of Southern Denmark

Page: 1

Related biology news :

1. Einstein researchers discover key to cell specialization
2. Study in underwater laboratory may help manage seaweed-eating fish that protect coral
3. UM doctoral student receives the Zale Parry Scholarship from Academy of Underwater Arts and Sciences
4. NOAA, Spain announce cooperative arrangement to preserve maritime underwater heritage
5. Underwater gliders may change how scientists track fish
6. IEEE touts NJIT professor for expertise in underwater acoustic communication
7. MBARI sends underwater robot to study Deepwater Horizon spill
8. Scientists report first remote, underwater detection of harmful algae, toxins
9. Toward cheap underwater sensor nets
10. An underwater drugstore?
11. Little Salt Spring underwater archeological site in Florida receives new funding
Post Your Comments:
(Date:11/12/2015)... LONDON , Nov. 11, 2015   ... and reliable analytical tools has been paving the ... and qualitative determination of discrete analytes in clinical, ... sensors are being predominantly used in medical applications, ... and environmental sectors due to continuous emphasis on ...
(Date:11/10/2015)... 2015 About signature verification ... to identify and verify the identity of an ... the secure and accurate method of authentication and ... individual because each individual,s signature is highly unique. ... dynamic signature of an individual is compared and ...
(Date:11/4/2015)... ALBANY, New York , November 4, 2015 /PRNewswire/ ... According to a new market report published by Transparency ... Size, Share, Growth, Trends and Forecast 2015 - 2022", ... value of US$ 30.3 bn by 2022. The market ... during the forecast period from 2015 to 2022. Rising ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... - Aeterna Zentaris Inc. (NASDAQ:  AEZS) (TSX: AEZ) (the "Company"), ... Toronto Stock Exchange, confirms that as of the date ... that would cause the recent movements in the Company,s ... About Aeterna Zentaris Inc. . ... Zentaris is a specialty biopharmaceutical company engaged in developing ...
(Date:11/24/2015)... LEXINGTON, Massachusetts , November 24, 2015 ... Officer, will participate in the Piper Jaffray 27 th Annual ... on Tuesday, December 1, 2015, at 8:30 a.m. EST (1:30 p.m. ... Poulton , Chief Financial Officer, will participate in the Piper Jaffray ... City , NY on Tuesday, December 1, 2015, at 8:30 ...
(Date:11/24/2015)... ... November 24, 2015 , ... In harsh industrial ... points for in-line sensors can represent a weak spot where leaking process media ... of retractable sensor housings , which are designed to tolerate extreme process conditions. ...
(Date:11/24/2015)... HemoShear Therapeutics, LLC, a privately held ... disorders, announced today the appointment of H. ... (BOD). Mr. Watkins is the former president and ... and also served as the chairman of the ... Chairman and CEO of HemoShear Therapeutics. "The combination ...
Breaking Biology Technology: