wikipedia "giant squid" article needs fixing

monty

Colossal Squid
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#1
I was looking at the wikipedia article on giant squids, at

http://en.wikipedia.org/wiki/Giant_squid

and found it has a few problems. Wikipedia's whole thing is that they allow, and even encourage, people to edit the articles, but I'm not positive I qualify.

In particular, it says:

One of the more unusual aspects of giant squid (as well as some other species of large squid) is their reliance upon the light weight of ammonia in relation to seawater to maintain neutral buoyancy in their natural environment, as they lack the gas-filled swim bladder that fish use for this function; instead, they use vast numbers of tiny "statocysts" (ammonia-filled cellular structures) throughout their bodies. This makes the giant squid unfit for human consumption, although sperm whales seem to be attracted by its taste.
It's certainly using "statocyst" incorrectly, and I thought the distribution of ammonia (or ammonium chloride) was just mixed in with muscle, not in any sort of cellular structures, but I'm less sure about that... I didn't see any description of the microscopic distribution in

http://www.tonmo.com/science/public/giantsquidbuoyancy.pdf

Anyway, it might be a good public service for one of the real teuthologists to go over the wikipedia page. Probably adding http://www.tonmo.com/science/public/giantsquidfacts.php to the links section would be good, too...
 

Squidman

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#2
I would start ranting if I wasn't so tired right now.
Pathetic job those folks are doing, isn't it? Of course, giant squid awareness isn't their top priority, eh?

-Squidman-
 

Melissa

Larger Pacific Striped Octopus
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#3
Monty, if you are able to identify that statocyst has been misused, you probably qualify, certainly moreso than the original author. Have at it, with a reference to the squid papers here! Those papers and the physiology forum are resource materials.

Melissa
 

monty

Colossal Squid
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#4
Melissa said:
Monty, if you are able to identify that statocyst has been misused, you probably qualify, certainly moreso than the original author. Have at it, with a reference to the squid papers here! Those papers and the physiology forum are resource materials.
Melissa
Well, I thought about it, but my concern was I don't know what the right answer is-- is the ammonia (or ammonium chloride) really distributed in little chambers (presumably called something other than statocyst)? Or is it just "dissolved" around the flesh? And what mechanism keeps the balance between sodium chloride and ammonium chloride to maintain neutral bouyancy? Is it some sort of ion pump, like in nerves? Is it neurally controlled? Is it a chemical reaction? The TONMO science article says it's not uniformly distributed, so what causes it to be inhomogeneous?

It seems like I only know enough to remove most of the paragraph... not fill in the right answer! Maybe some of that, no one knows, but I bet several people on TONMO know most of it...
 

Fujisawas Sake

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#5
Sorry folks, gotta disagree here -

You know, I wouldn't call this "pathetic" but rather a good start. The current academic shots being taken at Wikipedia belittle its main purpose; the free exchange of knowledge between interested parties. I would argue that this attack is anathema to what science is supposed to be. And there is a serious danger to simply dismissing knowledge by "non-academics".

That being said, and while I don't see too much bad information being tossed around here, please remember that this is not an established scientific journal. Being that they actually actively encourage people to write in and submit changes to observed errata, we should take full advantage of that opportunity to improve this free online database.

IN ADDITION keep this in mind: Scientific papers are not gospel either. I have seen a lot of errors in logic, methods, and observation that got through the legions of peer reviewers. If you having something "new" to add, do so. Stick it to the 'the man' if you are able.

Now... as far as the ammonium ion concentration goes, I would also disagree with the statocysts idea that the author points out. I was thinking specialized ion-storing vacuoles within the cells in the mantle, though as to which cells, I cannot suppose. Steve O's papers shed a little light on the concentration gradient across the whole animal, but not into which cells stored the ions and the mechanisms by which those ions are stored. Specialized vacuoles are generally the rule at the cellular level, though don't hold me to that, 'cause these puppies are some gnarly beasties.

Just my two cents.

John
 

Fujisawas Sake

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#6
monty said:
Well, I thought about it, but my concern was I don't know what the right answer is-- is the ammonia (or ammonium chloride) really distributed in little chambers (presumably called something other than statocyst)? Or is it just "dissolved" around the flesh? And what mechanism keeps the balance between sodium chloride and ammonium chloride to maintain neutral bouyancy? Is it some sort of ion pump, like in nerves? Is it neurally controlled? Is it a chemical reaction? The TONMO science article says it's not uniformly distributed, so what causes it to be inhomogeneous?

It seems like I only know enough to remove most of the paragraph... not fill in the right answer! Maybe some of that, no one knows, but I bet several people on TONMO know most of it...
Monty,

BTW, these questions are brilliant! You rule! :read:

John
 

Melissa

Larger Pacific Striped Octopus
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#7
I want to echo everything John wrote above - about need for mainstream (not academic) resources, the risks of leaving the dissemination of information to academics, the fact that there are errors in academe, and the value of an engaged populace. Monty, here I really mean you and other wikipedia readers and contributors. I edit and write a lot of academic and research stuff - new blood is always needed!

I'll leave the ammonium ion questions to you who know better, like Monty and Steve and John.

Melissa
 

monty

Colossal Squid
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#8
Fujisawas Sake said:
Monty,
BTW, these questions are brilliant! You rule! :read:
John
Nah. I'm just creatively ignorant... but thanks!

I'm wondering, if I had a giant squid, how I would answer some of those questions, but I'm assuming someone (likely SOS or Kat) who actually has a specimen to apply them to has thought about this a lot more than I have...

probably the right person to update the wikipedia page would have a copy of this:

Voight J.R., Portner H.O. and R.K. O'Dor 1994. A review of ammonia-mediated buoyancy in squids (Cephalopoda: Teuthoidea). Marine and Freshwater Behaviour and Physiology. 25 : pp.193-203

Weirdly, this is the only buoyancy article I got in CephBase when I searched on ammonia-- the rest were just about excretion.

Now that I've gotten a curious about it, I find that while Caltech theoretically has an online access subscription to that journal, I get a JOURNALNOTFOUND error... argh!
 

monty

Colossal Squid
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#9
Melissa said:
I want to echo everything John wrote above - about need for mainstream (not academic) resources, the risks of leaving the dissemination of information to academics, the fact that there are errors in academe, and the value of an engaged populace. Monty, here I really mean you and other wikipedia readers and contributors. I edit and write a lot of academic and research stuff - new blood is always needed!

I'll leave the ammonium ion questions to you who know better, like Monty and Steve and John.

Melissa
I certainly agree that wikipedia is a good thing, and that in general making knowledge available to the layman is a great thing... On the other hand, I have a strong personal frustration with inaccurate information in references, particularly when it's presented as undisputed fact. It seems (to me) like a lot of popular science stuff and pre-college teaching pushes things as "the whole truth" that are either wrong or incomplete, and I think this does a disservice, if not to the average public viewer, at least to the people who want to learn more, and then realize that a lot of what they learned initially turns out to be wrong.

Of course, I've had a counterpoint view from a friend of mine who is a museum exhibit science writer, who says that studies have shown that putting more than 50 words worth of info in a display drives people (or "average people" or something) away, so she feels that oversimpification is something of a necessary evil that comes with the territory. I worry that this is a case of "aiming at ONLY the average person," and that there could be a way to present things so that the average person gets it, while the non-average person can learn more details or clarification, but maybe the studies have shown somehow that this is impossible.

Anyway, I try to keep reminding myself of what I don't know as well as what I do, which probably makes me rambling and pedantic sometimes, but also makes me feel like I'm not misrepresenting much. So, I'm reluctant to put stuff I don't really know into wikipedia, even though I know the theory is that that would be self-corrected out.

But, maybe I should just edit the particular part that I know is wrong, about the statocyst, and maybe add a link to the archie and messie fact sheet... I just figured since there are real experts around, it would be doing wikipedia a service to have someone who knows more than I do check the stuff s/he would know off the top of his/her head, but I have no clue about...
 

Melissa

Larger Pacific Striped Octopus
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#10
Hi Monty

No one means to pressure you - it's encouragement. :wink:

monty said:
Anyway, I try to keep reminding myself of what I don't know as well as what I do, which probably makes me rambling and pedantic sometimes, but also makes me feel like I'm not misrepresenting much. So, I'm reluctant to put stuff I don't really know into wikipedia, even though I know the theory is that that would be self-corrected out.

But, maybe I should just edit the particular part that I know is wrong, about the statocyst, and maybe add a link to the archie and messie fact sheet... I just figured since there are real experts around, it would be doing wikipedia a service to have someone who knows more than I do check the stuff s/he would know off the top of his/her head, but I have no clue about...
The fact that you think about what you do not know makes you an even better person to do something like this. You might not be offended when someone makes it better. "Real" experts should be happy that someone has corrected some inaccuracies - and learned from their work.

Melissa
 

Steve O'Shea

Colossal Squid
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#11
monty said:
It's certainly using "statocyst" incorrectly, and I thought the distribution of ammonia (or ammonium chloride) was just mixed in with muscle, not in any sort of cellular structures, but I'm less sure about that... I didn't see any description of the microscopic distribution in
Too true; it has two statocysts, used for balance, not buoyancy. Whether the whale is attracted to crap-tasting food is another leap - maybe that's all that's available and it just tolerates it.

Sorry, I don't know how the ammonium ions are distributed throughout the flesh/cells. We just examined ionic distribution in cubes of tissue; we didn't differentiate inter- from intracellular ionic distribution.

I reviewed something a couple of days ago that curdled my blood; a supposed 5-minute check turned into a half-day recast. It happens all of the time - there's simply too much crap online.
 

monty

Colossal Squid
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#12
Steve O'Shea said:
Too true; it has two statocysts, used for balance, not buoyancy. Whether the whale is attracted to crap-tasting food is another leap - maybe that's all that's available and it just tolerates it.

Sorry, I don't know how the ammonium ions are distributed throughout the flesh/cells. We just examined ionic distribution in cubes of tissue; we didn't differentiate inter- from intracellular ionic distribution.

I reviewed something a couple of days ago that curdled my blood; a supposed 5-minute check turned into a half-day recast. It happens all of the time - there's simply too much crap online.
Ok, well I just went ahead and did my best at an edit... mostly corrected the ammonia and statocyst bits, put "females are bigger than males" rather than vice-versa, and added a link to the fact sheet. I'd still encourage others to look at it, though, since there was plenty I was unsure about....

How did you measure the ionic distribution? Just liquify it and to some sort of spectroscopy? I can't think of an imaging technique that I know would work, but I wouldn't be too shocked if there was some stain for ammonia or ammonium chloride in histology, but on a brief google search, I didn't find one...

I also looked on google for "ammonia squid" and found that a whole lot of people reference either that wikipedia article or wherever the original statocyst quote came from, and that "experts" alternatively say the ammonia is a concentration in the muscle, or in "pockets."
 

Melissa

Larger Pacific Striped Octopus
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#13
I didn't look at it before, but it's neat to see it and know that a TONMO member contributed and even corrected part of it. Go Monty!
 

Fujisawas Sake

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#15
monty said:
... and I thought the distribution of ammonia (or ammonium chloride) was just mixed in with muscle, not in any sort of cellular structures, but I'm less sure about that... I didn't see any description of the microscopic distribution in...
This got my attention earlier, and something about it kept ringing in my head. So I spoke to my friend Thomas about the distribution of ammonium ions in this squid, and he advised me of something which I had long forgotten.

Ammonium ions in solution (NH4+) are a by-product (waste) of protein metabolism and are highly toxic. Yeah, I know - "duh"- but bear with me here. By its nature, its a weak base, and emulsifies lipids into soaps through saponification. It also does this to phospholipids (think cell walls) so accretion of this ion in the system is a bad, bad thing. So a case can easily be made for specialized, ammonium-resistant vacuoles, or the squid muscles would suffer massive reduction damage by such ions. Vacuoles would be EXTREMELY hard to detect. Maybe something chemical in the endoplasmic reticulum?

Just my two cents.

John
 

monty

Colossal Squid
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#16
Fujisawas Sake said:
This got my attention earlier, and something about it kept ringing in my head. So I spoke to my friend Thomas about the distribution of ammonium ions in this squid, and he advised me of something which I had long forgotten.

Ammonium ions in solution (NH4+) are a by-product (waste) of protein metabolism and are highly toxic. Yeah, I know - "duh"- but bear with me here. By its nature, its a weak base, and emulsifies lipids into soaps through saponification. It also does this to phospholipids (think cell walls) so accretion of this ion in the system is a bad, bad thing. So a case can easily be made for specialized, ammonium-resistant vacuoles, or the squid muscles would suffer massive reduction damage by such ions. Vacuoles would be EXTREMELY hard to detect. Maybe something chemical in the endoplasmic reticulum?

Just my two cents.

John
Yeah, that certainly sounds like it would be a serious problem for cell walls, and that's fundamental enough that it's unlikely that Archi membranes evolved to somehow tolerate NH4+. So, I guess the question is scale-- are there intracellular vacuoles, or some sort of pockets lined with some protective sheath embedded in the flesh? I still also wonder how much active control there is in getting the ratios right for neutral buoyancy, too-- is there a fixed amount of "negative weight" from the ammonium chloride, or is there some active system that's moving it around (maybe it's re-routed from the excretory system into wherever it's stored?) I thought for a minute that if archi kept its density close to neutral, the squid could tense up muscles and become a little denser to sink, and relax to float, too, perhaps, but then I remembered that mollusk muscle can be thought of as a "muscular hydrostat" which conserves volume and mass, so it can't change density, just shape.... hmmmm....
 

Fujisawas Sake

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#17
Well, I would imagine that the ammonium chloride breaks down into constituent ammonium and chloride ions in solution anyway, given that NH4Cl is pretty soluble in water.

Maybe the issue is analogous to turtle anoxia. Certain turtles overwinter in ponds, and since some of these ponds freeze, the turtle is trapped underwater for some time. Given that their metabolic rates slow immensely, and gas exchange occurs through the cloaca, the major issue here is a buildup of Carbon Dioxide and resultant carbonic acid. Turtles use the bones of the shell as a "carbon sink" and therefore can tolderate several months' worth of CO2 buildup without suffocating.

Now, maybe there is an extensive mod of the Archi's excretory system that can serve as an ammonium sink. They use pretty well-developed metanephridia, but... Hmm...

Wait one second!! The major ion concentration gradient is in the mantle, right? Fish use their passive and active diffusion across their gills as a way to excrete excess ammonium and other ions, right? Do the ctenidia of Archis also serve such a function? Such a convergence with fish would not be out of the question. It just seems that continuous ion-pumping would get to be pretty metabolically costly for an animal that lives as an ambush predator. Then again, its not like its hunting gazelles on the Serengeti.

Wow, we really don't know much about these animals, do we? Gosh, as much as I hate to say this, it might be easier to find a related species, do some experiments on it, and extrapolate from that.

Just my two cents.

Sushi and Sake,

John
 

monty

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#18
Fujisawas Sake said:
Well, I would imagine that the ammonium chloride breaks down into constituent ammonium and chloride ions in solution anyway, given that NH4Cl is pretty soluble in water.

Maybe the issue is analogous to turtle anoxia. Certain turtles overwinter in ponds, and since some of these ponds freeze, the turtle is trapped underwater for some time. Given that their metabolic rates slow immensely, and gas exchange occurs through the cloaca, the major issue here is a buildup of Carbon Dioxide and resultant carbonic acid. Turtles use the bones of the shell as a "carbon sink" and therefore can tolderate several months' worth of CO2 buildup without suffocating.

Now, maybe there is an extensive mod of the Archi's excretory system that can serve as an ammonium sink. They use pretty well-developed metanephridia, but... Hmm...

Wait one second!! The major ion concentration gradient is in the mantle, right? Fish use their passive and active diffusion across their gills as a way to excrete excess ammonium and other ions, right? Do the ctenidia of Archis also serve such a function? Such a convergence with fish would not be out of the question. It just seems that continuous ion-pumping would get to be pretty metabolically costly for an animal that lives as an ambush predator. Then again, its not like its hunting gazelles on the Serengeti.

Wow, we really don't know much about these animals, do we? Gosh, as much as I hate to say this, it might be easier to find a related species, do some experiments on it, and extrapolate from that.

Just my two cents.

Sushi and Sake,

John
Hmm.... this is starting to get out of my league biochemistry-wise (mortal fear of organic chem and the like is the main reason I didn't try for a double major in biology). I noticed that there are a number of papers in cephbase on the ammonia secretion mechanisms in cephs (presumably mostly the ones that don't use it for buoyancy) but I didn't look at them closely.

Wouldn't the hypothetical ammonium sink have to be distributed around the body of the squid in roughly the same distribution as Steve found the ammonia concentration, rather than being confined to the excretory apparatus? Or are you saying that perhaps the storage developed in the excretory system at first, but then a mutation allowed it to be expressed in muscle tissue (hence everywhere) and that provided the very favorable neutral buoyancy property so it caught on?

My source for thinking the ions are in the form of Ammonium Chloride (presumably in solution, as you say) is from a short mention in Wells & O'Dor "Jet Propulsion and the Evolution of the Cephalopods" from Bull Marine Science 49(1-2):419-432 1991:

Where coleoids have, for one reason or another, returned to life-styles that would benefit from neutral buoyancy, they have generally achieved this by replacing sodium with ammonium chloride, a mechanism that leads to rather flabby animals but which, unlike the gas-filled shell, is not limited by implosion depth (Clarke et. al. 1979).
Clarke et. al. sounds like it may be similarly enlightening to the journal that's missing its online form:

Clarke, Denton, and Gilpin-Brown, "On the use of ammonium for buoyancy in squids," J. Mar. Biol. Ass. U.K.: 59 259-276

Weirdly, it's not in cephbase. It's also not in the Caltech or U of California library systems database (the whole journal, in fact!). Steve refers to it in his archi buoyancy article in the TONMO science section, too.

So I guess people have studied this, but only published it in hard-to-find places...
 

Steve O'Shea

Colossal Squid
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#19
monty said:
Weirdly, it's not in cephbase. It's also not in the Caltech or U of California library systems database (the whole journal, in fact!). Steve refers to it in his archi buoyancy article in the TONMO science section, too.
... a long time ago I was approached and asked to submit hard copies of my papers to cephbase; I didn't as I was led to believe that they only cite articles that they have a copy of (or some such thing) online. I thought that a little rank. Accordingly countless squillions of papers are not cited on cephbase, simply because they haven't got copies in a personal library!!

I don't think that that is an appropriate service; I thought it more a means of freely developing a library for a limited few.
 

Steve O'Shea

Colossal Squid
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#20
"There are now ~5900 ceph papers in our reference database, including 33 papers published in 2004, 119 papers published in 2003, 161 papers published in 2002 and 1103 references in pdf format, available for download. Currently, we are only able to sporadically enter new papers into the database. Please send reprints to Catriona Day, Fisheries Centre, Lower Mall Research Station, 2259 Lower Mall, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4 and email pdfs to cephbase @ hotmail.com. Reprints and pdfs we receive will be added to CephBase in time but there may be considerable delays. Thank you for your patience."
 

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