Talk:Cline (biology)

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Cline Instead Of Races[edit]

NOTE - The following discussion was originally on the "Cline" discussion. I have made that article into a disambiguation page, so I moved the discussion here where it belongs. Applejuicefool 02:32, 2 September 2006 (UTC)

Since race in biology means subspecies then cline might meet this term. The definition of cline seems to go with what was once thought as the 5 "races" so I will change it so considering these were mere differences in phenotypes and and not genotypes. The race article also indicates this. Zachorious 21:05, 14 April 2006 (UTC)

The following clause is a violation of WP:V -- "many anthropologists are now using cline instead of "race" to describe the 5 main distinct groups of humanity (Caucasoid, Mongoloid, Negroid, Australoid, and Capoid)." This demandsscholarly, peer-reviewed citation. Specifically, if you can find one scholarly peer-reviewed paper in the past 20 years that uses those specific "5 main distinct groups of humanity," then cite it. -- Frank W Sweet 10:22, 24 April 2006 (UTC)

Read the race article for more details. The 5 "races" fit the description of cline, so I will put it back. For example if cline meaning the color red and say Caucasoid meant light red. It still fits the color red and should therefore be included in the article. Similarly the 5 "races" are actually clines per definition as they have to do with phenotypes not completely isolated. Zachorious 2:56, 24 April 2006 (UTC)

You misunderstand. I have no problem with your relating the term "cline" to the term "race." My only problem is with the phrase ""many anthropologists are now using cline instead of "race" to describe the 5 main distinct groups of humanity (Caucasoid, Mongoloid, Negroid, Australoid, and Capoid)," which violates WP:V Tell you what. Let me suggest a phrasing that avoids the WP:V violation. -- Frank W Sweet 11:10, 24 April 2006 (UTC)

Oh yea that is fine too, although the race article did suggest that it wa anthropologists that are now starting to reject the race term for cline. But it's altight now. Zachorious 15:16, 25 April 2006 (UTC)

I was not really objecting to what you were saying. I was just being nitpicky about your using the singular rather than the plural. When you talk about many traits varying across the map (perhaps out of step with each other), then you should use the plural, "many clines." If you plot seven traits, then you are plotting seven clines. As the opening paragraph says, "a cline is a gradual change of a character or feature..."
Two different breeds of cattle (jersey and holstein, for instance) can blend into each other if their herdsmen allow it. So you would have two breeds (or "races" or "varieties" of cattle) that merge into each other as measured in the gradual transition of many clines (many independent traits). And although all the clines may transition at different rates, they all start at one extreme in the jersey and end at the other extreme in the holstein. This fact (that a cluster of traits all start and end in the same geographical spot in the transition from holstein to jersey) is precisely why we can say that holstein and jersey are two distinct "breeds," "varieties," or "races."
The problem with humans is that there is no collection of traits that behave in that fashion. The people with the kinkiest hair are not the ones with the darkest skin, and neither of those are the ones with the broadest noses. Each human trait varies smoothly in a cline, as you suggest, from one extreme to the other. But the clines do not align geographically so as to reveal "breeds," "varieties," or "races."
You cannot show the existence of "breeds," "varieties," or "races" in an organism unless you can show that there are clusters of clines that start in the same spot. In that sense, you cannot have "breeds," "varieties," or "races" unless you have clines. On the other hand, it is possible to have an organism with many clines that vary across the map but that never align to all start in the same spot. Such a creature (i.e.: H. sapiens) has many independent clines but no "breeds," "varieties," or "races" in a biological sense. Of course, "races" in a political or ethnic self-identity sense are very real indeed. -- Frank W Sweet 15:24, 25 April 2006 (UTC)

"Cline" does not work as a substitute for "race" because it means a continuous variation between two extremes of a feature (or cluster of features). It would make sense to say, for example, that "Central Asian populations show a cline between Caucasoid and Mongoloid features". It does not make sense to refer to "Mongoloid" as a "cline".--JWB 01:34, 27 May 2006 (UTC)

As I said below, I'm not a scientist, but I do have a passing interest in linguistics. I'm thinking the discussion about using cline instead of race comes from the understanding of a group of people possessing identifiable racial characteristics as a continuous variation. Each "race" itself is a cline, varying continuously within itself. In your example, Caucasoid and Mongoloid ARE clines...there are continuous variations within both designations. Applejuicefool 17:26, 31 August 2006 (UTC)

Essay?[edit]

The central large section of this article Rejection of "race" for cline resembles an essay (a well referenced one) not an informative encyclopedia article.--ZayZayEM 00:49, 5 May 2007 (UTC)

Agreed, I'v removed it. Alun (talk) 07:22, 13 March 2008 (UTC)
Although I've restored the section to allow discussion, in the long run I would have no objection to its removal. WBardwin (talk) 07:29, 13 March 2008 (UTC)
Ok, let's leave it a while to see if there are any serious considerations. Alun (talk) 07:34, 13 March 2008 (UTC)
Agree, it doesn't fit the article at all, and possibly should be merged into one of the 'Race' article's debated issues sections. If I were reading this for the first time, I would not only come away still having no idea what a cline is, but would know whoever wrote the article sure had strong feelings about the term "race". I've studied this stuff for a while now and this pretty much zero context in defining a cline. It's just one minor area it's used in, and in fact many biological anthropologists, like George Gill use cline and race as 2 criss crossing yet valid classification methods, rather than rival terms ( http://www.pbs.org/wgbh/nova/first/gill.html ), as well as Carleton S. Coon, who acknowledged a similar pattern across Mendelian populations, co-existing with 'race'. Thus, cline is it's own entity and not merely a biproduct of the race debate. All that said, the irony that the comparison to the term 'race' dwarfs the very definition of cline (what the article is supposed to be about) is pretty awkward. Cold polymer (talk) 14:59, 20 March 2008 (UTC)

Yes, it only mentions "cline" at the very end, and is also not correct in suggesting replacement of the word "race" with the word "cline". I haven't seen this elsewhere, and it isn't referenced. Emphasis has shifted from "race" to more nuanced views of population variation, but the latter is not described by a single word. --JWB (talk) 02:48, 21 March 2008 (UTC)

Rewrite ring species[edit]

It seems to be a summary of the main article, which itself is the not best written--Victor falk 13:19, 26 July 2007 (UTC)


I think the word "adjacent" should be "non-adjacent" else it makes no sense. Someone? — Preceding unsigned comment added by 74.81.189.18 (talk) 17:27, 1 March 2012 (UTC)

Earlier rejection of "races", and implicit suggestion of clines[edit]

I've found this, from Johann Gottfried von Herder (1744-1803):

Lastly, I could wish the distinctions between the human species, that have been made from a laudable zeal for discriminating science, not carried beyond due bounds. Some for instance have thought fit, to employ the term of races for four or five divisions, originally made in consequence of country or complexion: but I see no reason for this appellation. Race refers to a difference of origin, which in this case either does not exist, or in each of these countries, and under each of these complexions, comprises the most different races. For every nation is one people, having its own national form, as well as its own language: the climate, it is true, stamps on each its mark, or spreads over it a slight veil, but not sufficient to destroy the original national character. This originality of character extends even to families, and its transitions are as variable as imperceptible. In short, there are neither four or five races, nor exclusive varieties, on this Earth. Complexions run into each other: forms follow the genetic character: and upon the whole, all are at last but shades of the same great picture, extending through all ages, and over all parts of the Earth. They belong not, therefore, so properly to systematic natural history, as to the physico-geographical history of man.

--Extremophile 21:29, 16 October 2007 (UTC)


Wikipedia is not a dictionary[edit]

Wikipedia is an encyclopaedia, it is not a dictionary. The word cline is used in population genetics in exactly the same way it is used in any other way, it is not a technical word that describes any sort of biological phenomenon, it is an adjective that describes how allele frequencies are geographically distributed, the way it is used in population genetics is not a specialised use. We do not need a long discussion of "race", the fact that clinal genetic/phenotypic variation has been used to argue against categorical "races" should be addressed in articles specifically about taxonomy and "race" and not here. As far as I can see this article serves no purpose. If we want to say the genes/phenotypes vary clinally and we want to include a link to a definition of cline, then we can easily link to the Wiktionary definition like this [[wiktionary:cline|cline]], which gives cline. Wikipedia is not here to provide definitions, it is here to provide encyclopaedia articles, this article is just a definition of "cline". Alun (talk) 06:19, 13 March 2008 (UTC)

It's a notable topic, and if we can't write enough about it for its own article we could perhaps merge it with ecotype, which is similar but with separation between populations. Wiktionary is always a last resort. Richard001 (talk) 10:41, 8 April 2008 (UTC)
The idea that genes have a clinal distribution is notable, this should be discussed in the article Human genetic variation. Use of the word cline in population genetics is not a "topic" and is hardly notable, it's use is not specialist it is descriptive. This leaves little more than a definition of "cline" associated with "genetic distribution". As I said wikipedia is not a dictionary, the best this article can possibly hope to achieve is to give a definition of cline, the meaning of which is not restricted to genetics. It is an adjective, used in this context to describe how genes vary, it is not a population genetics technical term. How is it a "topic" in it's own right at all? How is it's use notable? I really don't think this article serves any purpose except to artificially inflate wikipedia with pointless articles that can not serve any encyclopaedic value. Alun (talk) 15:16, 8 April 2008 (UTC)
Alleles and haplotypes have a clinal distribution. Genes in the strict sense do not vary between between individuals in a population of one single species (normally) - you do not have one gene in some humans and another gene at the same locus in other humans. Read anything by Cavallli-Sforza to get an idea what's going on here. For an easy example, there is a cline of "typical Mongol" haplotypes all across Eurasia; certain genetic combinations run from very common in Mongolia to quite rare in central Europe. Dysmorodrepanis (talk) 02:51, 18 September 2008 (UTC)
I don't know what you mean by "genes in the strict sense". I think you are talking about a locus? In my experience the word gene is usually synonymous with allele, but that's hardly relevant. The question is not whether or not genes are distributed clinally, clearly they are, but whether we need an article called "Cline (genetics)", which I think we don't, use of the word "cline" in genetics is not technical or specialist, it is simply descriptive, so why have a special article about it? I don't see the relevance of your post to the discussion to be quite frank. Alun (talk) 06:40, 18 September 2008 (UTC)

Race again[edit]

There should really be some mention of the problem of human races in this article, since it's not that uncommon for physical anthropologists etc. to point out that "cline" is a rigorously definable and measurable concept, while "race" is not.... AnonMoos (talk) 16:05, 1 October 2008 (UTC)

Added a sentence, because the article really needed some reference to this... AnonMoos (talk) 11:33, 3 October 2008 (UTC)
I can't help but feel that's a non sequitur. So cline is definable, but how is that relevant to the non-definability of "race"? Alun (talk) 19:55, 3 October 2008 (UTC)
It may be a non-sequitur, but it's an established and somewhat conventionalized non-sequitur. The practical context in which it emerged is mid-to-late 20th century geneticists or physical anthropologists etc. replying to popular questions or assertions about the scientific basis of race, and pointing out that scientifically, "race" is rather poorly defined, and can only really be adequately measured by using rather high-level correlations -- while other things, such as the concept of gene cline, can be rigorously mathematically defined, and can often be fairly directly measured (without the need for abstruse higher-level statistical abstractions). I think that Ashley Montague wrote a whole book devoted to some degree to developing this theme... AnonMoos (talk) 21:26, 3 October 2008 (UTC)
I know all of the arguments, but they always occur in discussions about "race". I'm not against including some comment here about the idea that clinality demonstrates the non-concordance of characteristics and the non-discrete nature of variation. Some time ago the overwhelming majority of this article was devoted to a discussion of "race", it was really little more than a coatrack.[1] As long as we can avoid that I'm quite content. Maybe we could put in a bit more context, but I just don't want to go over the top. Cheers, Alun (talk) 15:28, 4 October 2008 (UTC)
Well, I just wanted to put in something, however brief; feel free to develop it further... AnonMoos (talk) 16:11, 4 October 2008 (UTC)

About humans[edit]

Clines are not related to races. Human races are not distinct sub-species. Races are phenotypical variations within the same sub-specie, homo sapiens sapiens. Skin colour certainly not follows genetic variation. For instance, Papuans are more closely related to Europeans than to Khoisan. walk victor falk talk 03:24, 2 February 2010 (UTC)

types of clines[edit]

The link to types of clines is confusing; I thought they would give examples of ecoclines, but rather they where different kinds of gradients. Addition of examples of, say, thermoclies leading to ecoclines would be helpfull.128.120.105.143 (talk) —Preceding undated comment added 22:47, 8 October 2010 (UTC).