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editI will start this discussion page for a very particular reason.
I will re-read this article, then amend, or comment on my initial discussion.
(Note: I did not know, nor do I agree that climate is part of the definition of a Climax community. Note added at end of this Discussion entry. And, I don't think the term Equilibrium, or "Steady state theory (literature) end" is a correct rdoesn't make it so.)(Mmcannis: I think this is from my 15 April 2006, entry)
- It is not; Only to the initial author/authors who think that it is just climate. Climate is obviously only one factor. The article states that "Climax community" as a term has been superceded. ...And by what?. The article certainly doesn't suggest the list of superceded terms. ...(from the SonoranDesertsAZ)..(And there are always a summation of vectors pushing things towards a "Climax Community")(i.e. 'steady-state')..-Mmcannis 05:40, 23 June 2007 (UTC)
The modern "tone" of 'expert' articles
editHaving grown up with the term "climax community", or "climax forest", I am surprised that:
- Not only is it no longer in vogue-
- There is a slew or arguments, and clarififications, emendations, ...New insights, and corrections.
Some history, and a persepective of the student:
- The student, of whatever age, who understands this term, thrown at them: a "climax community", with the knowledge of Biology, or Zoology/Botany, already has a clue as to what this term is referencing.
- I am pretty sure this article "Climax community" is implying that any new student, at any age, and at whatever decade of the 1900's, had to go out and read about, and learn: The history of the term: ' Climax community ' .
I am sorry to inform some people, a "climax community" has been seen by humans long before a person coined a term for it. Since Ecological succession is the other half of this discussion, let's immediately jump to the end of any succession. Any succession, does imply an end.
Apparently that hasn't stopped many people from arguing against a "Succession community", or a "Climax community".
So we want it both ways:
- A climax community can't exist, because we have all these good mind working reasons why not,...
- But ecological successions, occur everywhere, for all those same good smart reasons, but they never reach a "climax communtity"?
- So, what is wrong with this picture? Our global warming lets the changing gradients change so rapidly, we don't allow for climax communities anymore? Hmmm. MMcAnnisYumaAZMmcannis 07:08, 15 April 2006 (UTC)
response to MMcAnnins's points
editVegetation which is stable over the long term, you're right, MmCannis, has been observed since people began to observe vegetation. Yes. However the term "climax community" was coined by plant ecologist Frederic Clements around 1904. The term, as you're familiar with it, became a popular component of textbooks and natural history discussions only as a result of Clements's very wide influence on ecology through the late 1930s. And for Clements, climax communities are ideal types of vegetation which are by definition associated with particular regional climates. See Clements's 1916 book on this, Plant Succession, and the wikipedia article on him for more information. CHE 04:04, 28 April 2006 (UTC)
- Mmcannis 05:40, 23 June 2007 (UTC)The thing about the histoy of the term, "An individual" forms their idea of what the term means, long before they research where the term came from. I have been doing archaeology, specifically the Amarna letters. The 'climax', the end point, a turning point that then starts a new road, applies to many fields, not just this Botanical, or Biological term: "Climax Community". (It applies to the Amarna Period events.)
- The term implies that things have reached a "steady-stae".
- "Old-Growth" is a wonderful term, and useful. However, the single trees that end up being the "old-timers', are in the Bell Curve. If Old Growth doesn't address the fact that the average creatures/species, live far shorter lives than the individuals that are special in that Bell Curve, then a complete understanding of how it works has not been put forward, (elucidated). The 'old-timers' typically have a quality of "position", or a term from the 60's: "The Set", or: 'the setting', Like a Ponderosa in a dry wash bank, that was almost twice as large in diameter as an average tree-(with a virtually unlimited supply of intermittent water)...SonoranDesertGuy..-Mmcannis 05:40, 23 June 2007 (UTC)
The gradient
editFrom the "Climax community" article: "...that plant species distributed themselves along nutrient and other environmental gradients. " In the article, I was going to put the Wiki in for Gradient(See discussion weeks ago at Talk:Gradient), but it refers only to Vectors, and Math, etc. A gradient is a type of vector, but the term is also used linguistically. A vector is implied. What is really implied in using the term, is a Force-ing function, that is Strong, and gives the direction to forces, whether they are environmental, like temperature, sunlight, or chemical concentrations, or soil levels, etc. The variables, are too numerous. The problem with the forcing functions: they all add together and lead in a direction, but different subfunctions take their turns in the final directions.
- And.... that is why I was surprised to see that the article only focusses on climate. Any student of Biology, Zoology, and Botany knows that climate can be the big factor, the Primary function. But it doesn't have to be.
At the base of the Escarpment of the Porcupine Mountains of the western Upper Peninsula of Michigan, there is a succession forest of Hemlocks. I will bet, that speciation, is more the dominant factor of that forest than Climate(plus it is a very small stand of trees). In the Northeastern United States, or Northwestern United States, there climate probably is the correct analysis. ( But not in a small, local forest. )
- (I was going to say that maybe a small succession Hemlock forest, shows that: Regionally rules apply, for climate, temps, wind directions, rain, maybe...), but locally the exception forests should be studied.
- A good exception to the norm might be the coastal Redwoods. I understand, they all stand as a team, and cannot survive, as singles, or small groups. They are locally in the Westerly winds, the place on North America from northern Calif to northern Wash. where the long term climate assures there existence. Are they more a function of the Westerlies.(?) Just inland from the coast, are some of the driest deserts known, though they are at more northern latitudes.MMcAnnisYumaAZMmcannis 07:08, 15 April 2006 (UTC)
Kropotkin
editI deleted Kropotkin because he doesn't belong here in a discussion of a particular concept in plant ecology. Kropotkin is a useful addition to pages on the history of evolutionary thought, or anarchist throught, or the like, but the ecologists referenced here (esp. Clements and Whittaker) were not influenced by Kropotkin, nor were they in debate with him at any point. Kropotkin was part of very different debates. He is not referenced in the ecologists' literature on succession, so far as I have ever seen. You might have gotten a sense of his potential relevance from the lines about altruism and evolutionary theory. Those are based on a sloppy interpretation of Clements, so I have adjusted them. CHE 04:04, 28 April 2006 (UTC)
"Altruism"
editI realize "altruism" is in shudder-quotes here, but if anyone can offer evidence that Clements believed that populations which are part of a Clementsian climax community must directly favor some populations over others, as if they are in some special relationship, please post it. Because I believe that's what is intended by "altruism" here, right? Specifically, I suspect that what the contributor has in mind is that evolutionary theory demonstrated that many communities are structured by competition. The important thing to realize is that for Clements, too, climax communities are structured by competition, and positive or mutualistic (+/+) interactions among species are almost always mediated by some environmental condition. For example, large trees favor smaller shade plants only through their effect on light abundance. Clements described this sort of facultative interaction as "reaction" upon the local habitat, which then affects other species. So I've deleted the following, since I think it is misleading, and encourages the sense that, say, Kropotkin, is relevant:
- In addition, the maturation of evolutionary theory discredited the level of interspecies "altruism" required by Clements' theories.
Average conditions?
editIn an otherwise excellent re-write, CHE added the line:
- This equilibrium occurs because the climax community is composed of species best adapted to average conditions in that local area.
I don't think that "climax" species (however broad the usage of the term) are adapted to "average" conditions. Not even sure what "average" conditions would be. For the most part, later-successional species are adapted to a system that is very much to one end of the range of conditions experienced by a site. Species adapted to "average" conditions would be mid-successional species. Guettarda 05:22, 28 April 2006 (UTC)
Guettarda, Great comment--thanks, (and for your general endorsement, too, of the re-writing). You're right about this. At the same time, I think that sentence is ambiguous, and we're talking about two different meanings of "conditions." (1) You're referring to the very local conditions within the limits of the scope that can be affected by component organisms, ("reacted upon" by other plants, especially, in the Clementsian terminology). It is in that sense of "conditions" that mid-successional conditions might be considered average. (2) I was referring to macro-conditions typical for a region which do not vary over the course of succession and incorporate major seasonal variation--that is, climate beyond the range which varies from denudation to climax, e.g. the portion of climate which insures that no matter what the other local vegetation, tropical flowers will never live in Antarctica, short of some massive climate change. To show why my meaning of "conditions" is one I need to be meaning here, consider that the following three sentences are insconsistent, if conditions is used in your sense #1: (a) climaxes are defined by the climatic conditions of an area; (b) climaxes are relatively stable over the long-term; (c) climatic conditions vary signifcantly over the course of succession. For Clements, climax communities are therefore defined as those species which are best-adapted to the long-term typical conditions for an area. It's that physiological adaptation that prevents them from being displaced except where conditions depart from what is average or typical or normal in the long-term. Would it work for you to use "normal" or "typical"? CHE 18:16, 28 April 2006 (UTC)
Lead section
editThe lead section should reflect the important elements of the article, in a condensed form. One of the most important points is the fact that presently the "steady state theory" is seriuosly challenged. So, I propose the following lead section edition:
In ecology, climax community, or climatic climax community, is a historic term that expressed a biological community of plants and animals and fungi which, through the process of ecological succession — the development of vegetation in an area over time — had reached a steady state. This equilibrium was thought to occur because the climax community is composed of species best adapted to average conditions in that area. The term is sometimes also applied in soil development. It, nevertheless, has been found that steady state is more apparent than real, particularly if long enough periods of time are taken into consideration. Not withstanding that, it remains a useful concept.--Auró (talk) 07:02, 2 April 2013 (UTC)
- I endorse the revert, but I disagree with the last part - personally I think the climax concept is one of those bad ideas that we can't be rid of quickly enough...it's one of those mistakes that drives sloppy thinking that drives bad management decisions. Guettarda (talk) 21:26, 19 June 2013 (UTC)
- I think that when I wrote this, last year, the idea was included in the body of the article. I have re-read it now and see that it is no longer present. I therefore propose to suppress the sentence "Not withstanding that, it remains a useful concept".--Auró (talk) 11:16, 23 June 2013 (UTC)