Talk:Octopus
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Is there a marine biologist in the house?
This brief article makes no mention of the many interesting traits unique to octopuses, such as: ink sacs, color changing (though the article on cephalapods does mention it,) lack of any bones, three-heart circulatory system, and hunting habits. Could someone please update, I trust not my amateur knowledge.
One source (http://www.marinelab.sarasota.fl.us/OCTOPI.HTM) - Nocturnal (not a registered user)
The article says that they 'have a very short life span.' Just how long is it? Kent Wang 05:21, 28 Apr 2004 (UTC)
Arms, Tentacles or Limbs
The article says: Octopuses are characterized by their eight legs (properly called "tentacles").... Is this correct?
I had the impression that the eight legs were properly called 'arms' and that 'tentacles' referred to something else, the two additional long paddle-ended appendages of the giant squid for example. Thus one might say that the squid has eight arms and two tentacles. See, for example, http://www.australiancephalopods.com/occy_features.html: "One of the best known features of Octopuses is the fact that they have eight arms" This page uses the word 'arms' four times and 'tentacles' not at all; it was written by Dr. Mark Norman, a world-famous expert on cephalopods. Similarly, http://marine.alaskapacific.edu/octopus/anatomy.html uses the word 'arm', not 'tentacle'.
If there's no objection, I will correct the terminology in the article. Dominus 06:37 Apr 20, 2003 (UTC)
In Italy we're used to referring to the two long tentacles of squids as arms ("braccia"). The normal tentacles of octopuses and squids are always tentacoli, nor "legs" or "arms". Carnby.
Which one should be used. I'm not so sure that "arms" should be the term used, as they are technically neither arms nor legs. Why was tentacles removed?
The argument at the top of this page doesn't seem to have reached any real conclusion. Just that Marine biologists (and many other scientists) are inconsistent and international--ZayZayEM 22:20, 14 Oct 2004 (UTC)
- Typical english is to use "arm" for the four pairs of appendages common through all the coleoidea, and "tentacles" for the extra pair. - UtherSRG 12:43, 15 Oct 2004 (UTC)
- Should not "limbs" then be used when describing all 8?--ZayZayEM 07:46, 16 Oct 2004 (UTC)
- I disagree with ZayZayEM's evaluation. English scientific usage is as UtherSRG said, and consistently so. The terms used by Italian biologists when speaking in Italian are irrelevant since the article is written in English. -- Dominus 14:16, 15 Oct 2004 (UTC)
plural
As the article correctly says, octopi is not the correct English plural. It is not, however, a 'misconception' that octopus is from Latin. The OED states that octopus derives from modern Latin octōpus, which in turn derives from Greek. -- Heron
And how does the "common misconception" that octopus is Latin give us a plural which is so close to the original Greek oktopoi and so different from the Latin octopedes. If anything it sounds like octopi is anglicized Greek
- The common misconception stems from the -pus ending. It is a Latin ending, but not when it means "foot". The Latin -pus means something else. The Greek plural of -pus is -poi, while the Latin plural is -pi. cf. cactus (http://www.jimloy.com/language/plurals.htm) - UtherSRG 16:49, 5 Oct 2004 (UTC)
No, it is not. The Greek plural form of (okto)pous is (okto)podes. The term pous, podos, plural: podes ('foot' but also 'leg') is an "irregular noun" (much better: a diphthong stem). I've studied Greek at the university and checked also Liddell-Scott dictionary. It must be said also that oktapous/oktapodes (with accented alpha) was even more common than oktopous (with accented omega) in ancient Greece... Carnby
- Either form, octopuses or octopi is acceptable. Check a dictionary. Exploding Boy 21:07, Nov 15, 2004 (UTC)
- Octopi has become an acceptable alternatve through decades of misuse, but as English is a living language this has to be taken on the chin I guess.
Can someone please add the omikron to the Greek singular and plural forms? Exploding Boy 16:50, Nov 22, 2004 (UTC)
- Which one? Another "small letter omicron with psili" (ὀ), or a simple "small letter omicron" (ο)? I admit it's all Greek to me, but could you explain why there would be only 11 Google hits for οχταπόδι but 3830 for χταπόδι? - And after all that work you removed the 'term of endearment'? Femto 19:51, 22 Nov 2004 (UTC)
χταπόδι is a colloquialism. Just as we don't write "gunna" in formal writing, we shouldn't be writing "khtapothi"; the word is okhtapothi, from "okhta", meaning 8, and "pothia," meaning legs. Exploding Boy 20:05, Nov 22, 2004 (UTC)
- Do the Greeks know this? Femto 20:33, 22 Nov 2004 (UTC)
If you'd like to rephrase your question so it's both understandable and non-sarcastic, I'll try to reply. Exploding Boy 20:53, Nov 22, 2004 (UTC)
- A quick check at two online dictionaries, this (http://www.kypros.org/cgi-bin/lexicon) and babelfish (http://babelfish.altavista.com/), returned only the chi variant. I'd like to know from what authority do you speak, and is it applicable to an encyclopedia that should describe the common usage and not necessarily always the correct one. Femto 21:38, 22 Nov 2004 (UTC)
I grew up speaking and reading Greek, though admittedly I've largely lost it now. I looked at some of the online sources available; none seems particularly reliable, though I did find what appeared to be a scholarly article that contained both versions. I'll try looking in a proper dictionary, but at least both variants should be mentioned. Exploding Boy 21:59, Nov 22, 2004 (UTC)
- Good enough for me. I would agree that the formal variant should also be given, if the modern Greek word wasn't just an aside to the derivation of the English plural for the animal. It's obvious that somewhere on the way from ancient Greek an ο went missing, and if the 11:3830 ratio reflects common use, I'd say 'skip it' and just give the chi variant. Interestingly, many of those 11 hits are from restaurant menus. (And a Greek-Finnish word list, of all things. What is it with those Scandinavians? :) If it would be enough to mention the existance of the formal variant, how's the current edit? Femto 11:58, 23 Nov 2004 (UTC)
Greek or Latin??
According to the numerical prefix articles, it says that octa- is Greek and octo- is Latin. However, this article says that octo- is Greek. Any opinions?? 66.245.107.78 01:46, 15 Oct 2004 (UTC)
- All those octa/okto variants share the same Indo-European roots, if I got that right. Since then, those languages kept developing their own forms, as well as borrowing freely from each other. There may be a pattern, but it should be difficult to determine which is which only from the prefix of a word. This is the point, the article makes no hint at the origin of the prefix itself, just at that of the compound word. (I have no idea what this means for the other articles.) Femto 20:55, 5 Nov 2004 (UTC)
By the way, "nautilus" is another Latinized Greek word. Fortunately the link works just as well in the singular here. See Talk:Nautilus. Femto 20:55, 5 Nov 2004 (UTC)
image
This photo is good, but I'd like see one which more prominently displays its eight tentacles. Kent Wang 05:19, 28 Apr 2004 (UTC)
Does anyone know the species depicted in the image? - UtherSRG 12:31, 26 Oct 2004 (UTC)
- Not a clue, but according to http://www.photolib.noaa.gov/reef/reef2063.htm it was taken by Mohammed Al Momany in the Gulf of Aqaba, Red Sea. Femto 15:11, 26 Oct 2004 (UTC)
as seafood
>> In some cultures, octopuses are caught for food.
- Removed it because there's virtually no edible animal that isn't eaten somewhere. Which cultures? Octopus is a worldwide exported seafood, you can probably find some at your local supermarket. Still it would be worth to mention the seafood aspect somehow. How many million tons? Yes, millions - according to [1] (http://www.globalchange.umich.edu/globalchange2/current/lectures/fisheries/fisheries.html) about 2.5 million tons of cephalopods are harvested each year (I found no data about octopus in particular). Those pesky dolphins shouldn't get all the attention, eh? Femto 14:51, 29 Oct 2004 (UTC)
self?
the article says: "Octopuses also understand the concept of mirrored images and soon realize there's no use attempting to attack their own images. This seems to suggest that octopuses have some concept of a self; otherwise only monkeys, apes and humans, and possibly some species of dolphins, are smart enough to understand that their mirrored images are not other animals."
As stated, this does not seem tenable. Chimpanzees are thought to have a concept of self because they groom themselves in the mirror, showing that they can conceptually grasp that it is them being reflected back on themselves [needs reference]. Just not attacking the mirror does not demonstrate an awareness of self. Dogs and cats can do this. It seems that this evidence is pretty neutral with regard to whether the Octopus has a "concept of self". - anon
- You may be correct. An octopus's sense of taste (via their suckers) is high acute. They may get the point that attacking a mirror is pointless because they get no octopus taste (besides its own) from the mirror. However, it shouldn't be removed, only expanded to give other possibilities. - UtherSRG 21:03, 15 Nov 2004 (UTC)
Octopussy
>> Finally, there's octopussy (plural octopussies), which is used in British English and is based on a popular derivation from "pussy" ('she-cat'), but it's completely erroneous.
- To clarify, Octopussy is a James Bond movie, which is named after the Book by Ian Fleming, which in turn is named after one of the characters, who in turn is named by a blend of "octopus" and "pussycat" (obvious, but speculating here, I don't know the book or if there were earlier uses). Octopussy could be called a portmanteau word, but 'blend' seems more common and is just fine. Giving the trivial octopussies-plural here made little sense to me. Also it's less distracting to simply say "pussycat".
- Re:British English - It's not in my dictionary, so to speak. The web search for "site:uk octopussy -bond" was ...interesting, but can you cite some real uses? Femto 18:36, 18 Nov 2004 (UTC)
- Nearly every documentary involving octocpusses and has a BE narrator. Makes me cringe every time they say it. Never heard an AE speaker use it except in reference to Bond. - UtherSRG 18:57, 18 Nov 2004 (UTC)
- I'm neither British nor American, and not an English "speaker", literally. Either you're confusing a funny pronunciation of "pus-es" with "pussies", or I seriously don't get the joke. Femto 19:39, 18 Nov 2004 (UTC)
- Nearly every documentary involving octocpusses and has a BE narrator. Makes me cringe every time they say it. Never heard an AE speaker use it except in reference to Bond. - UtherSRG 18:57, 18 Nov 2004 (UTC)
Octopussy usages:
- [2] (http://homepage.mac.com/charles.kooij/iblog/C582507012/E301218954/) - (commented, Femto) A title of a weblog entry, among "I'm an 80s God!" and "Splish splosh"
- [3] (http://www.fortunecity.com/emachines/e11/86/cephpod.html) - A text heading, among creations like "macho mollusc". (Ugh, FortuneCity won't give me the images without tracking personal info)
- [4] (http://www.geocities.jp/oyryt/lembeh_straits_pictures.html) - An image caption, apparently from a Scandinavian photographer, on a Japan-hosted site!?
- UtherSRG 22:40, 18 Nov 2004 (UTC)
I was hoping for a BBC documentary transcript or something. All I can concede is that the term is sometimes used to refer to octopuses, but it's not mainstream English or in the dictionary, and I can't prove any direct connection to British English. I'm perfectly fine with the current edit though, what do you think? Femto 12:13, 19 Nov 2004 (UTC)
- I was hoping for such, too.... but I did the search quickly during class (searching for both cephalopod and octopussy). those were the (at least) minorly promising hits I could grab before I had to close extraneous windows. That all said, I couldn't leave well enough alone and made your link to the Bond movie more explicit. - UtherSRG 12:52, 19 Nov 2004 (UTC)
- No prob. And you never know when you'll need a page that explains how to bake a hedgehog. Femto 14:32, 19 Nov 2004 (UTC)
Re: rm bizarrerie - I've reverted because both the Bond name and the term of endearment derive from each other, and they are directly related to the subject of this article. "Octopussy" is a natural association and should be mentioned in a paragraph about words used for octopuses. Femto 13:40, 4 Dec 2004 (UTC)
Re: delete ridiculous facetiousness - see above. I think the facts themselves are appropriate to this article and shouldn't be simply removed with a 'minor' edit. Any suggestions how to make it less of a silly run-on sentence? Shorten it to "Finally, there is Octopussy, a blend name of octopus and pussycat, which is sometimes used as a term of endearment for octopuses."? Femto 13:38, 29 Jan 2005 (UTC)
See also Talk:Octopussy on the derivation of the word. Femto 14:31, 20 Apr 2005 (UTC)
Disputed
References to "Wells" in this section are to Octopus: Physiology and behaviour of an Advanced Invertebrate by M.J. Wells, Chapman and Hall, London, 1978. (ISBN 0470991976)
- Good job finding this information. Now be bold and edit the articles as appropriate. No need to insert {{dubious}} tags throughout unless there is some disagreement here on the talk. I'll try to comment in the secitons below. (As well, I'm going to modify some of your formatting. - UtherSRG 18:25, Jan 3, 2005 (UTC)
- Hrm. 1978 is a bit old. I've made some changes and removed the tags. Let's see if we can find something more recent, and I'll see about finding a local copy of Wells. - UtherSRG 03:35, Jan 4, 2005 (UTC)
- That was why I didn't just make the changes myself. -- Dominus 14:00, 4 Jan 2005 (UTC)
Blue-Ringed Octopus's rings
According to the article, the blue rings displayed by the Blue-ringed octopus are the product of its chromatophores:
- They also have specialized color changing skin cells called chromatophores ... the very poisonous Blue-ringed Octopus becomes bright yellow with blue rings when it is provoked...
However, Wells says that the chromatophores are always in the yellow-red-brown-black range:
- By the time the little animals settle out of the plankton, the population of chromatophores has become subdivided into two groups, a very dark set, which can vary from black or red-brown, and a paler series which appears red when contracted and pale orange-yellow in extension. (p. 283)
- The chromatophores themselves are all in the yellow-red-brown-black range. (p. 212)
Thus, the blue rings cannot be due to the chromatophores. Wells continues:
- Plainly, these two along cannot possibly account for the full range of colours that anoctopus can show. The explanation lies in the possession of two sorts of light-reflecting structure, the iridophores and the leucophores, lying beneath the chromatophores.
The iridophores, not the chromatophores, would appear to be responsible for the blue rings. -- Dominus 17:44, 3 Jan 2005 (UTC)
- I suggest adding mention of iridophores and leucophores to the article, and the also checking blue-ringed octopus for other changes needed. - UtherSRG 18:25, Jan 3, 2005 (UTC)
Color Vision
According the the article, octopuses have color vision:
- Octopuses ... can easily distinguish among colors and shapes in laboratory experiments. More impressive is that they can remember the shapes and colors and their meanings for up to two years ...
However, according to Wells, octopuses do not have color vision:
- Octopus is a colourful animal, capable of rapid colour change. It succeeds in matching its background and it employs colour changes in a range of displays directed at its own kind and at other animals. Prima facie one would expect octopuses to be able to distinguish between colours.
- The evidence available nearly all suggests that they cannot. Experiments have included discrimination learning, electroretinogram studies, and an examination of optomotor responses of animals in a striped drum. ... (p. 209)
And later on:
- All the available evidence suggests that Octopus is colour-blind. (p.284)
-- Dominus 17:22, 3 Jan 2005 (UTC)
- Probably stating something along the lines of noting "their abilities to match their pigmentation to the surrounding color and texture is more phenominal given that they are unable to see in color" would be right. - UtherSRG 18:25, Jan 3, 2005 (UTC)
Opening Jars
The article says:
- An octopus can also learn how to unscrew the lid of a jar with its arms...
However, according to Wells, this is not the case. Wells says:
- Crabs can be wrested from containers but the results appear to be achieved by chance and there is little indication that the octopus can learn to deal with the situation more efficiently with practice. The animal approaches and struggles with the apparatus until something happens; if it learns anything as a result of its experience it is only to be more persistent and vigorous. (p. 241)
-- Dominus 17:22, 3 Jan 2005 (UTC)
- Perhaps note their trial-and-error learning may not give them a straight-path solution, but that some successes can lead them to find the struggle worthy. - UtherSRG 18:25, Jan 3, 2005 (UTC)
Interesting documents about octopus intelligence and learning can be found here, in case someone wants more background for editing:
- http://www.dal.ca/~ceph/TCP/smarts.html
- http://www.nwf.org/nationalwildlife/article.cfm?articleId=604&issueId=53
Interesting article about defence mechanisms among two species of octopuses; "walking" as camouflage: New Scientist article (http://www.newscientist.com/article.ns?id=dn7194). -Tim Rhymeless (Er...let's shimmy) 06:05, 27 Mar 2005 (UTC)
- (Fixed the NS link.) More noteworthy, I'd like to point out that it also contains a link to an article titled "I spy with my little octopussy eye (http://www.newscientist.com/article.ns?id=mg17623643.000)"! Femto 10:23, 27 Mar 2005 (UTC)
Diet
Trying to extend the list of carnivorous animals at Carnivore. Are Octopuses (and squids) exclusively carnivorous??--ZayZayEM 03:27, 7 Apr 2005 (UTC)
- Octopuses are exclusively carnivorous. I believe squids are, but I don't know for sure. -- Dominus 02:20, 8 Apr 2005 (UTC)
Needed Additions
I'll try to add all these myself eventually, but if anyone already knows the answers (in other words, if you know more than I do now), please put in some of this stuff:
The suborders listed here are "Cirrina" and "Incirrina", but I think that "Cirrata" and "Incirrata" are more common. Does anyone know? I believe they are equivalent, but maybe that's not even right.
There is nothing in the page about reproduction of octopuses. Note that there is a common myth even among semi-experts that octopuses reproduce with the aid of one of their arms (true) and that it breaks off in the process (false). Only one (or perhaps a few) species actually lose their arm in reproduction.
Contrary to what the introductory information says, octopuses of the cirrata suborder do have internal shells. - Nabarry
- "Cirrina" and "Incirrina" are how they are listed in Current classification of Recent Cephalopoda (http://www.mnh.si.edu/cephs/newclass.pdf), which is what CephBase and WP:CEPH's taxonomy is based off of.
- I've added the distinction of the internal shell for the cirrate octos into the article, and I'll leave it to you to add in the reproduction information, although I may do it later if you don't get to it.
- On other matters: Please sign your comments with ~~~~ so we know who is in the discussion, and consider registering a username. - UtherSRG 11:40, Apr 26, 2005 (UTC)
- Thanks for suggestions and comments. I am new.
- I see that the classification website (http://www.mnh.si.edu/cephs/newclass.pdf) you listed uses Cirrina; also that website references the Integrated Taxonomic Information System (http://www.itis.usda.gov), which also lists the suborder as Cirrina. But Cirrata seems to be used pretty frequently: more pages come up on Google for Cirrata than for Cirrina. Do you know why this might be?
- I emailed Dr. James Wood from the Cephalopod Page (http://www.dal.ca/~ceph/TCP/index.html) (he uses Cirrata) and asked him if he knows the difference between the two. If you happen to know, it would be nice to put in a note in the classification. Otherwise I'll add it when he answers, if he knows.
- I think that even if Cirrata is an outmoded form, it seems to be used often enough that it deserves mention as a form that used to be common.
- Nabarry 12:50 PM, April 26, 2005 (PST)
Cirrina Page
I just created a page for Cirrina. It is actually more of a sub-stub, but I wanted to get it started. I'll add more tonight, and more throughout the week if I can find time.
I also removed the following sentence from the Octopus article: "The octopuses in the Cirrina suborder have two fins and an internal shell." I felt that it did not really fit into the paragraph.
I think that there must be a far better way of referencing the Cirrina page than the way I did it (footnote referring to the bottom of the paragraph). But I do think that since most people only know about Incirrina, Cirrina belongs elsewhere. For example, these sentences in the Octopus article are pretty neat: "A beak, similar in shape to a parrot's beak, is their only hard part. This enables them to squeeze through very narrow slits between underwater rocks, which is very helpful when they are fleeing from morays or other predating fish." But they aren't true of the Cirrina. The Cirrina have an internal shell and thus cannot squeeze through narrow slits and all that.
Let me know what you guys think; I'm not set on keeping Cirrina info off the Octopus page, since they are certainly octopuses. I just think it's easier this way.
Nabarry 05:38, 2 May 2005 (UTC)
