wikipedia "giant squid" article needs fixing

Clem

Architeuthis
Registered
Joined
Apr 6, 2003
Messages
1,839
Hello Monty,

Regarding the ability/inability of Archie to lift its tentacles above the water, I recall some discussion about it here at TONMO, and it was suggested that the animal may be able to lift them above the surface if they were in their "zipped" configuration. (Can't remember who said that. It might have been me, for all I know, and I don't qualify as an expert.) Archie's tentacles aren't particularly muscular, and are extremely flabby when the animal is dead; a moribund, weak Archie at the surface would have a hard time lifting these appendages. Then again, it should be noted that the classic sea serpent profile, presenting an undulating series of partially exposed coils with a "head" peeking above the surface, might be within an Archie's ability to project, since roughly half of the conjoined tentacles' length would still be underwater.

That's all I have to say on that matter, and would have left it at that, but I just had to do a Google search for "Achiteuthis tentacles, strength," and found this PDF, written by David Chung of the University of British Columbia. I can't judge the mathematics deployed, but the physical data, measurements, etc. seem very incomplete. If the maths were applied to a more accurate model, what would the results be? Cool stuff, and Mr. Chung is to be commended for tackling this slightly gonzo project. It may not be decisive, but it should be enough to qualify that Wiki line.

I just noticed Wiki's statement that the sperm whale and the sleeper shark are the only known predators of Architeuthis. That's only partially true, as juvenile Architeuthis specimens have been recovered from lancetfish and albatross stomachs, and there are reports of specimens recovered from billfish and sharks. The sperm whale and sleeper shark may be the only known predators of mature Architeuthis.

Cheers,
Clem
 

monty

TONMO Supporter
Staff member
Registered
Joined
Mar 8, 2004
Messages
4,884
Clem said:
Hello Monty,

Regarding the ability/inability of Archie to lift its tentacles above the water, I recall some discussion about it here at TONMO, and it was suggested that the animal may be able to lift them above the surface if they were in their "zipped" configuration. (Can't remember who said that. It might have been me, for all I know, and I don't qualify as an expert.) Archie's tentacles aren't particularly muscular, and are extremely flabby when the animal is dead; a moribund, weak Archie at the surface would have a hard time lifting these appendages. Then again, it should be noted that the classic sea serpent profile, presenting an undulating series of partially exposed coils with a "head" peeking above the surface, might be within an Archie's ability to project, since roughly half of the conjoined tentacles' length would still be underwater.

That's all I have to say on that matter, and would have left it at that, but I just had to do a Google search for "Achiteuthis tentacles, strength," and found this PDF, written by David Chung of the University of British Columbia. I can't judge the mathematics deployed, but the physical data, measurements, etc. seem very incomplete. If the maths were applied to a more accurate model, what would the results be? Cool stuff, and Mr. Chung is to be commended for tackling this slightly gonzo project. It may not be decisive, but it should be enough to qualify that Wiki line.

I just noticed Wiki's statement that the sperm whale and the sleeper shark are the only known predators of Architeuthis. That's only partially true, as juvenile Architeuthis specimens have been recovered from lancetfish and albatross stomachs, and there are reports of specimens recovered from billfish and sharks. The sperm whale and sleeper shark may be the only known predators of mature Architeuthis.

Cheers,
Clem

Yeah, the predator thing is reasonable. I think the pdf article is full of silly assumptions... I assume Archi tentacles are roughly the same muscle profile as those Kier describes in a number of papers, which definitiely do not have a central tube of 1/3R of fluid-- they're amost all muscle. Also, who cares if they can hold them statically at 45 degrees, when the normal operation of squid attacks is to shoot them out rapidly? So, I think the paper is interesting, but rather questionable. On the other hand, I don't have a better counterargument than "that's silly," and it certainly does seem like Archi attacks more through stealthy sneak-and-grab fishing than muscle power... maybe I should just leave it be. I know the ammoniacal squids are supposed to have weaker muscle per volume than other cephs, but I'm still skeptical. Maybe I should combine that pdf paper with some of the info in Kier's papers on this kind of stuff, and see if I get the same answer (in my copious free time).

It's probably silly to pursue this too far, anyway, since regardless of archi's ability to lift its arms out of water, I think it's accurate to say that all evidence points to a lifestyle that would be quite incompatible with attacking a ship, which is their point. :razz:
 

monty

TONMO Supporter
Staff member
Registered
Joined
Mar 8, 2004
Messages
4,884
another dubious-sounding thing has appeared on the wikipedia giant squid page:

male giant squid are equipped with a prehensile spermataphore-depositing tube, or Hectocotylus, of over 90 cm (three feet) in length, which extends from inside the animal's mantle and apparently is used to inject sperm-containing packets into the female squid's arms

Unless I'm mistaken, a hectocotylus always refers to a modified arm of a ceph, while I believe the organ referred to in architeuthis is generally known as a penis, and is not related to the arms at all. Could one of you anatomical teuthologists verify or refute this, so I can make the appropriate edit, please?

(never mind, I confirmed that I was correct in the Architeuthis Reproduction article, thanks!)
 

Top