Help with a report please

Eagleray

Blue Ring
Registered
Joined
Sep 14, 2003
Messages
47
#1
My sixth grade student have just finished research papers. A few of my students decided on the topic of octopus. (Kiss up points?) In one paper, the student stated that octopus are deaf. I could not find any information to back this up, as a sixth bibliography isn't always 100% correct. Can anyone tell me if this is the case?
Thanks
Beth
 

Jean

Colossal Squid
Supporter
Joined
Nov 19, 2002
Messages
4,218
Location
Dunedin, New Zealand
#3
Hi Beth,

That's a toughy!

According Hanlon & Messenger (Cephalopod behaviour) cephalopods are quite sensitive to low frequency vibrations (~10Hz) but there are arguements over whether or not this can be called "hearing". It's really a problem of definitions. Cephs have no air filled cavities with associated structures that can detect the pressure waves of sound! BUT the statocyst chamber and statoliths maybe able to do the job as the nerves leading off from them respond to low frequecy vibrations (called infrasounds!).

So I don't think you can mark your student wrong, especially when the scientists can't agree!

Hope this helps!

J

reference:

Hanlon, R. T., Messenger, J. B. 1996. Cephalopod Behaviour. Cambridge University Press. p. 14
 

WhiteKiboko

TONMO Supporter
Supporter
Joined
Feb 15, 2003
Messages
2,702
Location
Charleston
#4
i know there's been discussion about squid, but im not sure about octos.... try the Search function to peruse the forums...
 

joel_ang

Architeuthis
Registered
Joined
May 15, 2003
Messages
2,028
#5
I think they are deaf as they don't get too shocked when I yell. It came out in a documentry too saying they were unable to hear.
 

Jean

Colossal Squid
Supporter
Joined
Nov 19, 2002
Messages
4,218
Location
Dunedin, New Zealand
#6
joel_ang said:
I think they are deaf as they don't get too shocked when I yell. It came out in a documentry too saying they were unable to hear.
Depends on what you call "hearing" Joel, Sound is after all only vibration which we detect with hairs and a set of little bones in our ears. Cephs can detect vibration (most likely) with the statocyst chamber and statoliths much the same idea!

As for not responding when you yell? well I rather doubt your voice would vibrate as low as 10Hz, which is the "hearing" range of a ceph. There is precendent on land. Elephants hear much lower frequencies than we do, and of course dogs can hear much higher frequencies.........!

J
 

Members online

No members online now.

Forum statistics

Threads
19,485
Messages
202,576
Members
8,349
Latest member
ChadicusQuenchicus

Monty Awards

TONMOCON IV (2011): Terri
TONMOCON V (2013): Jean
TONMOCON VI (2015): Taollan
TONMOCON VII (2018): ekocak

About the Monty Awards
Top