• TONMOCON VII Announced | MBL at Woods Hole | Apr 6-8, 2018
  • Thanks for visiting! TONMO is the world's greatest online cephalopod enthusiast community, with interactive content going back to May of 2000, and a biennial conference. If you'd like to join in on the fun, become a TONMO member -- it's easy and free. You can follow us on Facebook and Twitter for more cephy goodness.


octopus arm types/uses

kindkind

Larval Mass
Registered
Joined
Dec 3, 2007
Messages
1
#1
hey there.

I have been searching the web trying to find what each arm of the octopus is generally used for. I know the third arm is used in mating and has a special tip. What are the other 7 used for? Thanks.
 

monty

TONMO Supporter
Staff member
Supporter
Joined
Mar 8, 2004
Messages
4,887
#2
kindkind;105905 said:
hey there.

I have been searching the web trying to find what each arm of the octopus is generally used for. I know the third arm is used in mating and has a special tip. What are the other 7 used for? Thanks.
:welcome: to TONMO

As far as I know, there isn't any particular usage pattern in most cases... often, they explore with all their arms at once. For walking behaviors and diving onto crabs, they use their arms in a coordinated way, but they're still mostly doing the same things a lot of the time. I'm not sure if they have a preference for behaviors that aren't symmetric; it seems like they often grab hold of something solid with the back 4 arms and use the front ones for tug-of-war, and they might use the front arms more often for one-arm strikes on small prey. I suspect that the "walking coconut impersonation" that aculeatus does always uses the same arm pair, but Mucktopus would be the person to ask for sure on that one.
 

DWhatley

Cthulhu
Staff member
Moderator
Joined
Sep 4, 2006
Messages
19,811
Location
Gainesville, GA
#3
Mucktopus mentions in the paper noted on the home page that the enlarged suckers were found on only some of the arms of the species she was recording. My two merc males that are easily observed (albeit under red light only) have enlarged suckers on all eight arms. I mentioned this to Crissy and she said that it is more common to see them on two or four but not all eight arms BUT they still don't have a definitive answer as to their use.
 

robyn

Vampyroteuthis
Supporter
Joined
Jan 19, 2007
Messages
299
#4
try these:

Ruth A Byrne , Michael J Kuba , Daniela V Meisel , Ulrike Griebel , Jennifer A Mather. 2006, Does Octopus vulgaris Have Preferred Arms? J Comp Psychol. 120(3)

Ruth A Byrne , Michael J Kuba , Daniela V Meisel , Ulrike Griebel , Jennifer A Mather. 2006. Octopus arm choice is strongly influenced by eye use. Behav Brain Res. 2006 Jun 21.

And tangentially:

Ruth A. Byrne Michael J. Kuba and Daniela V. Meisel 2004. Lateralized eye use in Octopus vulgaris shows antisymmetrical distribution. Animal Behaviour: 68 (5).

hope this helps!
 

Graeme

Vampyroteuthis
Registered
Joined
Sep 26, 2005
Messages
352
#5
Generally I think all the arms are the same except for, as you say, the Hectocotylised arm. But they might exhibit arm preference. Best thing to do is check out those papers that Robyn provided.


And welcome to the boards :)
 

Members online

No members online now.