Glossary questions and requests

[Jools]

All,

This sticky is to be used for all requests to add or edit things within the glossary page and for confirmation that they've been added.

Jools

[bronzefry, posts: 2198]

Thanks for the sticky note, Jools. I've compiled a "wish list" overnight. Any assistance with these definitions would be appreciated. The more we can do this in-house, the better. I've put (spelling?) where I'm unsure of my spelling.
Melanistic(spelling?)
Albino
Supraoccipital
Bubblenest
Hybrid
F1
Larva
Juvenile
Sub-Adult
Adult
Lateral Line
Schoal
School
Swim Bladder
Gonopodium(spelling?)
Weberian Apperatus
Dither Fish
If anybody can tackle one or two words, this would be most helpful.
Thanks!
Amanda

[MatsP]

F1 (and F0 and F2):
These terms define the level of captive breeding, where F0 is a wildcaught specimen, F1 is first generation captive bred (off-sprint from F0), F2 is second generation captive bred (parents are F1). Most people don't care and track it past F2 - it's just captive bred at that point. The importance here is that wild-caught specimens are supposedly more separate genetically, so better genetically to produce healthy off-spring and reduced risk of inbreeding-related deformities.

Hybrid:
A cross-bred individual where the parents are different species.

Dither fish:
Fish that makes other (shy) fish feel safe. It works by the principle that the shy fish thinks "Oh, those little neons obviously think it's safe, so if it's safe for them it should be for me too".

Dither fish can also help aggressive species "forget" to be agressive to conspecifics by chasing away the dither fish - in this case, it's important that the dither fish is quite fast swimmers, or they'll end up beaten up - and that they are stupid enough that they still swim back to the agressive fish's area again and again...

Swim-bladder:
A "container" for air that the fish can compress and enlarge through muscular activiaty to control it's own bouyancy - so that the fish can decide what level in the water it stays at. By compressing the swim-bladder, the density (weight per volume) gets higher, and thus it's further down in the water, and releasing the pressure on the swim-bladder, the fish can get higher in the water.

[MatsP]

Albino:
Lacking pigmentation (melanin) causing the animal (fish) to be completely white. A true albino has red eyes. There are other forms of pigmentation "disorders" - See also Amelanism:

Melanism:
"Overload" of melanin - the animal becomes completely black or very dark compared to it's conspecifics.

Amelanism:
"Underload" of melanin - similar to albinism, but may have some colour for example in eyes.

Leucism:
Another word for Amelanism.

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Mats

[MatsP]

Gonopodium:
Modified anal fin of Livebearers that is used to deliver sperm into the females vent.

Supraoccipital:
A median bone at the upper rear end of the cranium [Now that clarifies everything - I think we need a drawing here!]

Bubblenest:
A nest for the female to lay eggs in, built by one or both parent(s) from secretions and air.

Larva:
The stadium of fish when they have hatched (i.e. they are no longer inside the egg-shell), but yet to be free-swimming fry. In human terms before the baby is toddler but after "birth".

Juvenile:
Young fish - in human terms somewhere pre-puberty.

Sub-adult:
Fish just short of adult-hood - teenager in puberty in human terms.

Adult:
Fish that is mature enough to reproduce successfully - in human terms late teens onwards.

Lateral line:
[From fishbase.org]:A sensory organ of fishes which consists of a canal running along the side of the body and communicating via sensory pores through scales to the exterior; functions in perceiving low frequency vibrations and pressure differences in general.

School:
A group of fishes that swim together, usually in the same orientation at all times. [Paraphrazed from fishbase.]

Shoal:
Alternative spelling of School. Also terms for underwater bank of mud/sand/gravel or the area of water where it goes from shallow to deep. [loosely quoted from Fishbase].

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Mats

[MatsP]

I maybe should add that some of those are "My understanding" rather than dictionary look-ups, so if someone is of a different opinion or have other better explanations, feel free to add/subtract/modify.

--
Mats

[Silurus]

Weberian Apparatus:

The modified first four or five vertebrae in a group of freshwater fishes (Otophysi) that connect the dorsal wall of the swimbladder to the inner ear. This increases the sensitivity of otophysans to sound. Otophysans comprise much of the world's freshwater fish diversity, and include carps, loaches, characins, catfishes and electric (knife) fishes.

[bronzefry, posts: 2198]

Jools, how would you like me to approach the fishbase definitions? If it's paraphrased, do we need to cite? I'll leave those alone for the moment. Mats, you're understanding of the term is basically what we're looking for. We want this so that anybody, from beginner to graduate student and beyond can grasp the meaning. Some terms, like Weberian Apperatus(thanks, Silurus), require a technical description. At some point, the glossary will be large enough that the technical terms within a definition will cross-reference one another. I need to get a lot more words in first. One step at a time.
Amanda

[Jools]

I don't want any direct lifting becuase, aside from any copyright issues, the page strongly needs to be in terms that, as much as is possible, do not need further defining. Take for example:

The modified first four or five vertebrae in a group of freshwater fishes (Otophysi) that connect the dorsal wall of the swimbladder to the inner ear. This increases the sensitivity of otophysans to sound. Otophysans comprise much of the world's freshwater fish diversity, and include carps, loaches, characins, catfishes and electric (knife) fishes.

My view is:

Vertebrae isn't a fish specific term and it's generally known what this means even though it's a technical term, it's OK.

Swimbladder needs to be linked to a defn for that term but it has to be used as there is no alternative.

Dorsal wall better written as Dorsal (top) wall?

Electric (knife) fishes is an excellent example of using a correct term with an inclusive vernacular term.

Jools

[housewren, posts: 38]

I have been under the impression that "school" and "shoal" are not the same.

That a "school" is a highly-ordered group of fish with members going the same direction and maintaining a fixed distance between neighboring fish in the group (similar to MatsP's definition).

Whereas a "shoal" is a loosely-organized group of fish with members traveling in the same general direction, but some going faster, others slower, not maintaining a fixed distance between individuals; individuals frequently leave the group and go by themselves (e.g., Corydoras catfish are shoaling fish, but not schooling fish).

Cheri

[bronzefry, posts: 2198]

From the reading I've been doing, there are subtle differences and multiple meanings. A shoal is a group of fish that swims together. It is also a shallow part of a river.

A school of fish not only swims as a group, but swim in the same direction. A school may also exhibit purposeful behavior of some kind, such as evading a predator. School seems to be more an Americanized term. Does anybody know why?
Amanda

[MatsP]

I'm certainly not a "Living dictionary", so I can't know all words by heart, so for the definition of School and Shoal, I looked it up on the web, and the first reference to do with fish came up from Fishbase. Fishbase specifically defines Shoal as:

1) A school, 2) a submerged ridge, bank, or bar consisting of, or covered by, unconsolidated sediments (mud, sand, gravel) which is at or near enough to the water surface to constitute a danger to navigation, 3) said of waters where there is a change in depth from deep to shallow.

So according to fishbase, the word School and Shoal are used to indicate the same type of groupings of fish, but Shoal can also mean other things [School can also mean someplace that one goes to learn things].

If anyone can be bothered to get out a Oxford English Dictionary or similar and find the defintion of each of the two words, please feel free to give me the definitions. Unfortunatly, my copy of OED is still in storage awaiting the finishing of renovation of the house we've recently bought....

I'll also work on rephrazing the definitions that are direct lifts. Will do later today.

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Mats

[MatsP]

Lateral line:
A line of "holes" in the side of the fish, which the fish uses to sense vibrations (including sound) in the water.

Supraoccipital:
I don't actually understand the explanation of this, so I think Silurus may have to explain this one...

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Mats

[housewren, posts: 38]

MatsP,

Sorry, I wasn't trying to be critical of what you've done. I really appreciate the time you are putting in to provide definitions for the glossary. The distinctions in "definitions" for schooling and shoaling I gave were the one's that I had been led to understand from various things I had read, although I did not know their source. I checked Webster's dictionary, and it reflected what you (and FishBase) indicated. This, and OED (I would imagine) are not scientific dictionaries, though, and may not have the nuances of scientific meaning.

This made me curious where my idea had originated, so I googled "shoal school fish" to see if I could find the source for the distinction I had come to understand. Among several sites that use "shoal" as MatsP defined it, I also found several that used it the way I do. Finally, I found what is probably the original source of my idea:

Tien, J. H., D. I. Rubenstein & S. A. Levin (2004). [Dynamics of fish shoals: identifying key decision rules. Evolutionary Ecology Research 6: 555-565] cites Pitcher (1983), who "defines a social aggregation of fish as a shoal, with a highly polarized shoal constituting a school."

The reference for Pitcher is:

Pitcher, T.J. 1983. Heuristic definitions of shoaling behaviour. Anim. Behav., 31: 611â??613.

Sorry, I don't have access to Animal Behaviour to check the definition directly.

I'll be content either way PC wants to define it, but I find it convenient to be able to differentiate between the two types of groups.

Cheri

[Marc van Arc]

If anyone can be bothered to get out a Oxford English Dictionary or similar and find the defintion of each of the two words, please feel free to give me the definitions.

Thes are the relevant definitions from the Longman:
Shoal:
- a large group (of fish) swimming together

School:
- a large group of one kind of fish or certain other sea animals swimming together

This implies that school is used for sea fish.....(?).

[Silurus]

Lateral line:
A line of "holes" in the side of the fish, which the fish uses to sense vibrations (including sound) in the water.

The lateral line is not exactly that. The lateral line is part of the laterosensory system in a fish, which consist of a series of anastomosing canals (that open out to sensory pores) distributed throughout the body (they are particularly prominent in the head region, in addition to being located along the lateral line). The lateral line is that part of the system that runs along the middle of the body, and typically consists of a series of pores arranged in a longitudinal row (although in a number of fishes, the pores are actually situated at the end of canals that branch off of the main line). The laterosensory system is a pressure-sensitive system, i.e. it detects changes in water pressure as a result of movement.

I can tell you that the supraoccipital is a bone on the back of the head, but without a diagram, it's impossible to define it clearly in terms that are easy to understand.

[MatsP]

Cheri, no offense taken - as I said, I'm not a living dictionary, I'm just looking things up and trying to come up with defintions that are good for the site. If they are not right, they are no good for the site. Since Fishbase seemed to think that Shoal and School was the same (and that's how I'd understood it), I thought that was good enough. And although OED is not a scientific dictionary, it's probably fair to say that even minute differences in the meaning of a word is often described in it - but alas, I can't lok it up to find out if it is so in this case or not.

So would you agree with these defintions:

Shoal: A group of fish, usually all of the same species, that swim together as a group.

School: Generally the same as a shoal, but is sometimes used to mean a closer shoal where all fish have the same orientation, like the ones forming patterns in the film Nemo.

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Mats

[Jools]

I'll check with Clare and come back to this, but isn't shoal the collective noun for a group of fish and school a behaviour of such a group of fish with an inference (as pointed out) that they're the same species and generally going in the same direction?

Jools

[MatsP]

Lateral line:
A line of "holes" in the side of the fish, which the fish uses to sense vibrations (including sound) in the water.

The lateral line is not exactly that. The lateral line is part of the laterosensory system in a fish, which consist of a series of anastomosing canals (that open out to sensory pores) distributed throughout the body (they are particularly prominent in the head region, in addition to being located along the lateral line). The lateral line is that part of the system that runs along the middle of the body, and typically consists of a series of pores arranged in a longitudinal row (although in a number of fishes, the pores are actually situated at the end of canals that branch off of the main line). The laterosensory system is a pressure-sensitive system, i.e. it detects changes in water pressure as a result of movement.

I can tell you that the supraoccipital is a bone on the back of the head, but without a diagram, it's impossible to define it clearly in terms that are easy to understand.

How about:
A line of pores in the side of the fish connected to the nervous system, which the fish uses to sense pressure changes in the water (such as other fish/animals moving, vibrations and sound).

A bit shorter and less precise, but if someone actually want the long defition, I suppose they can always ask and we'll refer back to your post, HH?

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Mats

[Jools]

On the shoal / school thing, Clare agrees with me and also adds that school is an older word and that the use of shoal to describe a behaviour is a fairly recent evolution in terms of the use of the word. She also adds that school tends to have marine connotations. As a softer word shoal is likely to gain ground over school (as in Kirk and Church) but this can take centuries rather than decades.

Go on, edit that!

BTW, good effort in putting the words Nemo, fish and school in the same page, that's get us some traffic from Google!

Jools