Talk:Natural selection: Difference between revisions

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• Archive 1 (up to April '04)

I've added back the reference to Wells and Matthew, with references this time. They really deserve mention in the article, and separate articles of their own, too. Even Darwin admitted in "An Historical Sketch", which he added to later editions of The Origin of Species, that they thought of natural selection before he did, although Wells' applied it "only to races of man, and to certain characters alone," while Matthew "clearly saw...the full force of the principle of natural selection." Gould describes both proposals as "evolutionary."--Johnstone 02:52, 3 Nov 2004 (UTC)

Right, we have http://www.talkorigins.org/faqs/precursors/precursnatsel.html which claims that Darwin read neither. I think these need mentioning, but not in the lead because it just confuses things. The point is that Darwin took his ideas from others, but provided the first coherent synthesis of evolution. Dunc|☺ 11:55, 3 Nov 2004 (UTC)

I agree that a separate section is a better better place. I didn't mean to imply that Darwin plagiarized the idea. It's pretty clear from anything I've read that he was completely unaware of the earlier work. Actually, much of his work was quite original.--Johnstone 01:56, 4 Nov 2004 (UTC)

"To be precise, natural selection is not truly a "mechanism" in itself, as opposed to something like gravity. Instead, natural selection is the result of genetic and environmental forces acting upon an organism." I think this depends on your definition of mechanism. So it might be better to say something along the lines of: "To be precise, natural selection is not truly a "mechanism" in itself, at least not in the same sense as gravity is. Natural selection is the result of genetic and environmental forces acting upon an organism." GWC Autumn 68 ce 2004 15.10 EDT

• * * *

I also am concerned about the current language: "It is important to note that the term 'natural selection' is often used in the inaccurate yet fairly harmless metaphorical sense as having causal status...natural selection is not truly a "mechanism" in itself..."

Who wrote this? Let's be aware that this definition contradicts modern expert opinion. For example, the Penguin Dictionary of Biology (10th edition, 2001)-- which I realize is copywrited material, and so cannot be used on the Wikipedia page, but still (I hope) may be referred to here as an authoritative source -- defines "natural selection" as "(the) most widely accepted theory concerning the principal causal mechanism of evolutionary change...".

I propose that either someone should please stand up and take responsibility for the Wikipedia "important note" with a better defense, or else that note should be removed. It's certainly confusing when the reader encounters a section called "Mechanisms of NS" after seeing that it's "not truly a mechanism". IMHO, the IF-THEN statements are indeed mechanistic logic.

--Brad

I wonder if this page should include links to pages on other mechanisms of evolution such as niche construction and sexual selection.

--Betty

Is is true that Natural Selection is the only process whereby higher order and sophistication can be attained out of randomness (ie, no designer)?

So when people say Natural Selection can't be true because something as sophisticated as life as we know it couldn't have possibly have risen out of chaos, they're forgetting that's what the whole theory's all about.

GWC Autumn 68 ce 2004 15.15 EDT

Most biological sciences reject words like "sophistication" as species-centric. The Darwinian oncept that is relevant is fitness, and who is to say that we are more fit than bacteria? (Unless, you meant by "higher order" all life. I certainly think bacteria and I are both more sophisticated than rockes. But I don't know what rocks think -- and I am not in any rush to conclude that, if I don't know what rocks think, it is their fault). Slrubenstein

The theory is about the origins of species -- not the origins of sophistication. Slrubenstein

With Selection ?

I removed the following from the disambiguatory note, because it seemed out of place: Natural selection as talked about below was not the brain child of Charles Darwin, but rather of Edward Blyth expressed in a paper in 1835. (for more details check out - http://www.thedarwinpapers.com/oldsite/Number2/Darwin2Html.htm) --goethean ॐ 7 July 2005 20:41 (UTC)

We already have an article on Edward Blyth, who anticipated nat seln as a mechanism for keeping spp constant, and after Darwin published The Origin corresponded with Darwin. Nevertheless, creationists use him within their personal attacks on Darwin, partially because he was a clergyman. See Darwin's precursors and influences: natural selection Dunc|☺ 7 July 2005 20:48 (UTC)

So...that means we are leaving it out? (I don't care, I'm just asking.) --goethean ॐ 7 July 2005 20:58 (UTC)

Well, if you read the article :) --> Natural_selection#History_of_the_principle Dunc|☺ 7 July 2005 22:17 (UTC)

I had read that. I've now looked at the article history and see that my edit was correct. Question answered. Accordingly, I'm striking out the vandal's text here on the talk page. --goethean ॐ 7 July 2005 22:24 (UTC)

In the section, "Scope and role", the following text in bold was deleted by an anon without explanation:

Natural selection need not apply solely to biological organisms; in theory, it applies to all systems in which entities reproduce in a way that includes both inheritance and variation. Thus, a form of natural selection can occur in the non-biological realm. Computer-based systems have been shown that natural selection can be be highly effective in adapting entities to their environments. However, Stephen Wolfram, who has extensively studied such systems, has concluded that they also have shown that natural selection per se does not originate complexity, something that is often attributed to it:

My own work on cellular automata in the early 1980s showed that great complexity could be generated just from simple programs, without any process like natural selection. But although I and others believed that my result

s should be relevant to biological systems there was still a pervasive belief that the level of complexity seen in biology must somehow be uniquely associated with natural selection. In the late 1980s the study of artificial life caused several detailed computer simulations of natural selection to be done, and these simulations reproduced various known features of biological evolution. But from looking at such simulations, as well as from my own experiments done from 1980 onwards, I increasingly came to believe that almost any complexity being generated had its origin in phenomena similar to those I had seen in cellular automata—and had essentially nothing to do with natural selection. (Wolfram, p. 1001)'

I have restored it to read as follows:

However, mathematician and computer scientist Stephen Wolfram has concluded, based on extensive research with such systems, that they have also demonstrated that natural selection per se does not originate complexity, something that is often attributed to it: "I increasingly came to believe that almost any complexity being generated had its origin in phenomena similar to those I had seen in cellular automata—and had essentially nothing to do with natural selection. (Wolfram, p. 1001)

I've trimmed it because, while it's a more complete thought, it was simply taking too much room. However, without such a quote, the portayal of the role of natural selection, as observed in computer-based implementations, would be incomplete. It's an important conclusion drawn by someone who's particularly expert in the field.--Johnstone 23:45, 19 July 2005 (UTC)[reply]

I can well understand why someone would delete such material. It doesn't make reference to other people (eg Dawkins) who have similarly pointed out that the process of evolution by natural selection applies to non-organic systems (eg. crystaline structures in clays, I think that was Dawkins' pre-biotic example). It also has a bit of a fawning tone, is poorly integrated with the rest of the material in the entry (the debate about nat sel not generating complexity, these are issues discussed throughout the article as a whole, or only in this one section and then without presenting contrasting views?). Fundamentally this section is something subtly, but significantly different from the rest of the section, "natural" selection in artificial systems. Clearly this is a topic you feel stongly about, I suggest you flesh it out (with more than just one source of information) in a page unto itself dealing with nat sel in abiotic systems. Pete.Hurd 05:18, 20 July 2005 (UTC)[reply]

Unless I'm misunderstanding you, the page you suggest already exists: artificial life. I agree that the idea could be handled more completely there. However, see below about inclusion in this article.--Johnstone 03:12, 21 July 2005 (UTC)[reply]

A lot of people are dismissive of Wolfram's attempt to explain everything in the world vias cellular automata, and the quote is nothing more than a plug for his idea of how the world works. Wolfram has no particular expertice in the field of natural selection, AFAIK. It adds very little to anyone's understanding of what's going on. On the other hand, there is nothing about Lenski and Ofria's work with "Avida" which has demonstrated that natural selection can produce such complexity. Guettarda 13:29, 20 July 2005 (UTC)[reply]

I certainly didn't mean it to be plug for Wolfram, only the idea it represents. I would have no problem with including a mention of the claims made by Lenski and Ofria, or their type of work in general. But I think that a better approach may be to state the idea in an indirect manner (see proposal below). I am certainly aware that Wolfram has his critics (Lenski and Ofria have their fair share of critics, too.) I think this is sufficiently offset by the fact that the claim is being made by someone who's studied computer-based systems so deeply over such a long time, and the fact that it deals with the very widely held assumption of what natural selection actually does—and which may very well be wrong(!) It deserves at least a "by the way" mention.--Johnstone 03:12, 21 July 2005 (UTC)[reply]

I think having some mention to Lenski & Ofria's work as a rebuttal to Wolfram's claims is of real pedagogical value, and therefore worth retaining in wikipedia, but not here in nat sel. I think this stuff really belongs in a page related to genetic algorithms, cellular automata and the like, with a wider selection of views pro and con and a more complete broad view of the issues discussed. Right now it's one ideosyncratic view presented in isolation without adequately being worked into the topic. my 2c. Pete.Hurd 19:55, 20 July 2005 (UTC)[reply]

Please see my remarks above. It's important that the point also be made in this article, at least very briefly, because it deals with such a fundamental aspect of the subject: it's function. I agree that the handling of the idea could be improved; I've taken crack at integrating it better. Here's a proposed new wording (improvement suggestions welcome):

Natural selection need not apply solely to biological organisms; in theory, it applies to all systems in which entities reproduce in a way that includes both inheritance and variation. Thus, a form of natural selection can occur in the non-biological realm. Computer-based systems (e.g., artificial life) have shown that natural selection can be be highly effective in adapting entities to their environments; whether such systems have demonstrated that natural selection per se can generate complexity is contested.^[1], ^

==References==

1. ^ Wolfram, Stephen (2002). A New Kind of Science. Wolfram Media, Inc. ISBN 1579550088
2. ^ Lenski RE, Ofria C, Pennock RT, Adami C., 2003. "The evolutionary origin of complex features." Nature. 2003 May 8;423(6936):139-44.

--Johnstone 03:12, 21 July 2005 (UTC)[reply]

Actually, I take back the proposal to refer to the paper by Lenski et. al.. I forgot that it doesn't really deal with natural selection, but with a form of automated artificial selection. In order to evolve complexity, the program is set up to reward the digital organisms that shows mutations in the direction of the goal.--Johnstone 00:19, 22 July 2005 (UTC)[reply]

just wanted to say hi to you guys/gals. i am marcos antezana, a professional empirical and theoretical evolutionary biologist/geneticist who furthermore really cares about the verbal structure of evolutionary and biological discourse. english is my fifth language though, so beware.

i would like to help this project in bringing the best of evolutionary thinking and knowledge to the world and for free. i have also asked several colleagues to join this effort and to improve the articles in their fields of expertise. -- best to you all -- marcos

Welcome, Marcos. Please put talk page comments at the bottom. Also, if you set up your user page and are a registered user, you can use four tildes as an automatic signiture. Slrubenstein | Talk 23:51, 11 November 2005 (UTC)[reply]

As a visitor to this page, I found the opening paragraph to be confusing:

Natural selection is the process by which biological individuals that are endowed with favorable or deleterious traits end up reproducing more or less than other individuals that do not possess such traits. Differential reproduction imposed by random factors is normally not considered to be an instance of natural selection because natural selection requires that differential reproduction be caused by differences between individuals. When a superior trait is heritable so that in the next generation one observes more individuals displaying the trait, one speaks of adaptive evolution by natural selection. Evolution, therefore, can involve changes not driven by natural selection; and natural selection is not sufficient for evolutionary change to take place, let alone for adaptive evolutionary change (since the latter requires that the selected traits be heritable). In general, however, adaptive evolution requires natural selection because the possibility that favorable traits become more frequent across generations due to random fluctuations in trait occurrence, is negligible (see genetic drift). Favorable traits that owe their occurrence in a population to the fact that the genes encoding them were enriched in the population through evolution by natural selection are called adaptations.

• What does "Differential reproduction" mean?
• What "factors" does "random factors" refer to?
• What does "adaptive evolution" mean? Is this somehow different from "regular" evolution?
• Is the line, " requires that differential reproduction be caused by differences between individuals", tautological?
• Why does it start discussing Evolution when its role in evolution hasn't even been raised?
• What is a "superior trait"? (It seems to me that an audience that knows these terms wouldn't be reading an introductory article on NS.)
• How do you "enrich" a gene?
• Couldn't it be (alot) shorter?

In any case, it is virtually opaque, and mostly incoherent. I tried to edit it but was reverted. Which is fine, but at least replace it with something readable. Limbo socrates 20:00, 30 December 2005 (UTC)[reply]

if you read the text carefully you will see that all your questions are already answered. nobody will mind if you make the english more precise but please do not change the content unless you are fully positive that there is an error or omission. same regarding succintness, but do not forget that often repeating something in technical terms is not "redundant". Marcosantezana 04:33, 31 December 2005 (UTC)[reply]

Some observations

• First, I agree that the Wikipedia:Lead section is too long, it attempts to be rigorous and exhaustive rather than introducing material to come. I suggest deleting the second paragraph, the history is better covered in the section lter on, and the rest doesn't pay it's rent. The second paragraph, the one that deals with levels of selection, is a topic that deserves to be expanded to a section in the main body (and eventually an article unto itself). The fourth, fifth & sixth paragraphs need to be tightened up if they are to stay in the lead section, or merged into the appropriate sections of the main article. The last paragraph of the lead section is redundant, repeating what is in the initial paragraph. I think that would bring the introduction closer to the Wikipedia:Manual of Style and make it do the job of introducing better.
• I believe Marcos intends "adaptive evolution" to mean "evolution that is not mere genetic drift", ambiguous. Certainly could use cleaning up.
• The sentence "requires that differential reproduction be caused by differences between individuals" isn't tautological because a huge amount of variance in reproductive success has more to do with stochastic environmental effects than individual variation.

my 2c. Pete.Hurd 06:29, 31 December 2005 (UTC)[reply]

pete is right about the imbalance but that conclusion assumes that the remaining parts of the article are done deals. i consider instead that the remaining parts need to be expanded a lot. once they will be the intro will not feel that long anymore. the article should be considered under construction. another possibility would be to consolidate the whole thing into a single piece of text without repetitions and then subdivide, etc (or not). also, i tried to mention in a very quick way the main issues related to selection to make sure they are there right away so that the reader gets the punch line immediately and can then choose to look for in-depth treatment in the remaining of the article or via links. that's why darwin is still there (i found it there btw before i started contributing and i thought it made sense when i saw it albeit i wanted to have a merely conceptual abstract intro), not as exhaustive treatment of the history but as a express teaser and as context that stresses why evolution by natural selection was so well received when it was proposed Marcosantezana 15:14, 31 December 2005 (UTC)[reply]

I do not think anyone is suggesting changing the content of the article itself. But I think we should consider changing the content of the opening paragraph - NOT to make it inaccurate, but to make it more accessible. I am well-versed in evolutionary theory, and while I understand the opening paragraph I can easily see how non-specialists would find it confusing and daunting. I think the problem with the contents of the opening is it is a summary or abstract of the whoole article. My suggestion is to see the first paragraph as a real "introduction," stating in the simplest of terms what natural selection means, who developed the theory, and why it is importnt - and leave it to the body of the article to go into all of the details. I do not think I am disagreeing with any of the participants in this discussion, just adding another angle. Slrubenstein | Talk 18:43, 31 December 2005 (UTC)[reply]

good intentions won't eliminate the fact that the article is not done and won't be for a while. so one should avoid talking about what the best introduction to a finished article would be when the article is not finished. on the other hand one has to make sure the the content is correct and complete for people who are using the article as reference right now. the intro part as it is now is complete regarding the crucial issues, but the following parts are quite "narrative". of course if the first part is daunting it should be clarified and made more reader-friendly. please let's all try to rephrase things so the text becomes clearer. however, do think that when people find a long article they often read only the beginning so one should not give them a sense that things are easy since in that case they tend to let their prejudices fill the gaps. a complete summary-like "introduction" will function both as a summary for readers and as guidance for further expanding the article. but it does not have to be written in obscure sentences or like a children's encyclopedia. Marcosantezana 19:28, 31 December 2005 (UTC)[reply]

I'd like to point out that the WP style guide suggests 2-3 paragraphs of lead section. It's just too long now, and much of the material that is in there is simply not introductory. I'm under no illusions that the rest of the article is done. Marcos has put a lot of work into this, but clearly there's a lot more to do. Some of this will be accomplished by moving stuff out of the lead section into the rest of the article. As for the rigour vs. simplifiying/"dumbing down" of the lead section, I'd just like to point to the style guide.

"It is even more important here than for the rest of the article that the text be accessible, and some consideration should be given to creating interest in reading the whole article"

"Begins with a definition or clear description of the subject at hand. This is made as absolutely clear to the nonspecialist as the subject matter itself will allow."

"The purpose of an encyclopedia is to codify human knowledge in a way that is most accessible to the most people, and this demands clear descriptions of what the subject matter is about. So we aren't just dropped into the middle of the subject from the first word"

I think the aim should be to say nothing *wrong* in the lead section, but to say less. Following that Saint Exupery "perfecton is not acheived when there's nothing more to add, but when there's nothing more to be taken away" kind of a way. Everything in the lead section has to pay it's rent, otherwise it goes into the main body, or gets the chop. Best Regards, Pete.Hurd 19:48, 31 December 2005 (UTC)[reply]

citing the high standards of wiki won't make the article any better or make it any more useful to the people who will use it as reference. so let's see who can write the wonder intro paragraph. it has to mention differential reproduction due to differences in biological performance which are themselves the result of phenotypic differences between the relevant units of selection. it is wrong to commit to individuals, to adaptation, and to genetic differences as the cause of the trait and fitness differences. furthermore i do not see where in the remaining paragraphs a lot of crucial intro stuff could fit. it's up to you to propose where you want to put it. and remember that an article that looks good cannot be the only goal since wiki is about knowledge for others rather than about pleasing our esthetic senses or adhering to wiki's revealed standards of presentation (which are only meant as flexible quidance, btw). finally with the exception of the historical stuff, my personal opinion is that the stuff after the introduction is superfluous. if i did not get rid of it it's only because i did not want to break any eggs. Marcosantezana 00:20, 1 January 2006 (UTC)[reply]

I think the opening is much clearer now (I am not arguing that it cannot be improved upon) but I think the question now is, how much of the material in the opening can be moved into the body? Slrubenstein | Talk 23:12, 4 January 2006 (UTC)[reply]

great job. some word choices are awkward, some content got lost, etc, but these are small details. congratulations. however, the too-long-intro argument may come back but i think one should simply accept that the following sections have not yet reached their full length. Marcosantezana 02:10, 5 January 2006 (UTC)[reply]

Aye, nice work. I don't think the intro too long problem went away at all... but I'd say that the too long intro problem isn't the biggest problem. I do think that keeping the intro down to 2-3 paragraphs will improve the article as a whole as the problems with the rest of the article incorporate stuff now in the intro. Pete.Hurd 03:24, 5 January 2006 (UTC)[reply]

clap, clap, clap Nice job! It is a longer opening but it hits the real important stuff right off. By the third paragraph I felt I had the gist of it. --Limbo socrates 23:03, 6 January 2006 (UTC)[reply]

Thanks! And thanks for calling attention to it. Wikipedia is always a work in process, but it helps when people such as yourself can pinpoint places that need more attention. I'm sure as other editors keep working on this it will get even beter, Slrubenstein | Talk 23:14, 6 January 2006 (UTC)[reply]

I've noticed that the pages dealing with creationism enjoy a healthy representation of critiques and opposing viewpoints, which this page does not. I think including a section that deals with this issue is important for a couple reasons.(Or--better yet--relocate one of the better articles dealing with the point I'm about to make as a section of this article or--failing that--at least link to one of them. BTW, there are at least two or three of those articles and someone should probably erase the lesser quality ones.)

First, from a philosophical perspective, the concept of natural selection seems to be a tautology or truism. As this article states, natural selection represents the view that nature presents the most adaptable (and most likely to produce thriving offspring) specimens with the carrot of survival and the least adaptable(and the less likely to produce offspring) with the carrot of extinction in order to ensure the survival of the fittest. But what places one in the category of "fittest"? It seems that the fittest would have to be those that successfully reproduce. In essence, we say that natural selection is the device that ensures that the fittest will reproduce while identfying the fit as those that reproduce. Given this, it seems that natural selection is the secularist counterpart to the Cartesian circle.

Secondly, Darwin made this point:"For I am well aware that scarcely a single point is discuss in this volume on which facts can be adduced, often apparently leading to conclusions directly opposite to those which I have arrived. A fair result can be obtained only by fully stating and balancing the facts and arguments on each side of the question." On this point, I agree with the man. We need a discussion of substance on this issue. Today, the debate concerning evolution is mainly carried out by narrow-minded assholes like Steven Pinker and Pat Robertson. Let's not be like them. Let's give each view representation and debate the resulting positions on their merits--the view that creationists are idiots and that evolution is an errorless and universally accepted explanation for the origin of the species is lazy and cartoonish.Eskatos 13:21, 21 January 2006 (UTC)[reply]

the fallacious tautology "argument" (advanced in 1976 by the shrewd rh peters and later by many other conceptuologists) is demolished in the article text indirectly (in the way it was done by elliot sober). i made sure to cover it since it's quite loved among naive "conceptual" people. you should please reread the article and consider to start thinking before delivering stale lines that have already been debunked in the literature and even under your own nose. but if everybody wishes explicit treatment of this idiocy i can provide it, but i personally do not think it belongs in the article. Marcosantezana 16:25, 21 January 2006 (UTC)[reply]

I can think no other criticisms than the thoughoughly debunked "tautology" argument that belong in Natural Selection. Your second point pertains more to Evolution, not Natural Selection. Natural Selection was identified as a mechanism for maintaining Platonic ideal types under a creationist view before Darwin came along (natural selection removed the forms which deviated excessively from the true form). It might be worthwhile to have a section framing and debunking the "tautology" hoo-haw, just to make it super-easy to find by those who need educating on the point. But let me add that calling people "narrow-minded assholes" just makes me want to ignore everything you have to say. You may find people respond better to editors who act more like educated adults. Pete.Hurd 17:44, 21 January 2006 (UTC)[reply]

I've just added a todo list to this talk page. I'd like to invite you all to write down any suggestions you may have for the improvement of the article, and work on any of the items already suggested. I hope this will help us make better progress. - Samsara _contrib ^talk 16:37, 24 January 2006 (UTC)[reply]

It seems that those of you who have been working on this article for a while may be too attached to the Lead Section to be able to trim it down. I don't want to go in straight away and start hacking away at it after you've all put so much work into it, so I'll just post a few suggestions here for debate.

1. The first paragraph starts off as an excellent introduction, but breaks down starting with the "Before Darwin..." sentence. For the first paragraph, it is not necessary to describe the pre-Darwin philosophies, and while the remainder of the paragraph contains useful information, it is far too technical. I'm a biologist, and even I have to focus to get through those sentences. It almost seems as if someone wanted it to be hard for non-biologists to read. So, take out the historical reference (or move to the history section), and replace the jumble of science-speak with a plain english explanation of the genetic basis of variation and selection.
2. The second paragraph belongs in the history section - so much so that it's already there in a slightly different form.
3. In the third paragraph, the second and third sentences could use some simplifying, and the whole paragraph could be moved to the Mechanisms section.
4. Items of debate, such as the issue of whether natural selection functions at levels other than the individual level (as discussed in the fourth paragraph), do not belong in the lead section unless they are integral for the basic understanding of the subject (which this is not). Move to Mechanisms, or make a new section for "Current Issues" (or somesuch). By now, I think I've made my point about everything being too complex and technical, so I'll stop mentioning it now.
5. Paragraph 5: Non-biologists won't know what "fecundity" is. This paragraph makes a good point about the two realms of natural selection, but could stand to be clarified a bit. I might take a stab at it later when I have time.
6. I like paragraph 6 and think it should stay.
7. Paragraph 7: Avoid classifying some traits as "better" than others in an absolute sense; use "better adapted" or "better suited to environmental pressures", for example.
8. The final paragraph is good.

Cheers! --Barefootmatt 21:13, 1 February 2006 (UTC) Marcosantezana 19:23, 3 February 2006 (UTC) Yeah, agreement on most your points (I've made a few of them before myself, pulling out history paragraphs from lead, for instance). For a start, let me suggest you place a draft 1st paragraph replacement here on the talk page. I think a "levels of selection" section could pretty much be dropped into the article now. Pete.Hurd 21:47, 1 February 2006 (UTC)[reply]

the main thing here is that this is reference article, so removing content because it feels like this or feels like that, is frivolous. this article is supposed to allow anybody to get the best and most important punch lines about a topic. this is not only about about letting people feel that they already know what they are reading/seeing (that's american tv) or about introducing recalcitrant youngsters to a new fish oil.

ever read britannica's nat.selection article? it's not for children although it's bad quality sometimes because the author does not always know well what he/she is talking about.

"i am a biologist"... means little. i know many *evol*biologists who do not know well what natural selection means and implies, especially not regarding what people need to know about the concept (which often requires knowing how people tend to misundertand the concept).

just an example, you two are challenging the unit of selection part. well that part is really very important in order to let people understand that ascribing things to natural selection is a very complex task, and also to expose them to what the criteria are to do so (causality dissection).

if people knew that, nobody would be panting and jumping around poor richard dawkins. (mostly non-specialists actually, duh).

furthermore causality dissection is what allows one to debunk the circularity fallacy. but of course knowing that a base can mutate is soooo much important, right?

so the unit thing is there for a few very good reasons.

i often have to look up words when i use encyclopedias and i do it with joy. certainly i won't fault the encyclopedia for my not knowing them. should we adopt the vocabulary of fox news ?

now, if you guys want to challenge content it cannot be out of whim or esthetics or feelings. let's work on the "technical" words (although i see none that are not defined right away, and all are very easy to understand).

"this does not belong here". please if you know why think first. or i ask about it.

"The second paragraph belongs in the history section". are you kidding? don't you realize that the purpose of the paragraph is not so much darwin etc but stressing the fact that the questions of adaptation and speciation are central not only to biology but to any persons's weltanschauung and that selection explains both quite cogently and that for that reason the idea was and is extraodinarly important? furthermore this passage also presents indirectly the central question of speciation with depth that few specialists could convey (but rc lewontin can).

neither of these two things are "current topics", believe me. this is knowlegge about selection everybody should have.

i initially was against the conceptual history part (but did not say it) because i thought the article should be about natural things. but i reconsidered. there will for sure many be readers who will profit from getting a lead and the gist about the conceptual history, and now they get it.

besides, it is very short and tells people something very important about how great ideas originate. (yes, it normally happens against the will of people who want to see and read only what they already know).

but this is such a waste of time. why don't you guys contribute to the body of the article better? it is in pretty bad shape, full of boring common places. once the body will be ripe, let's go back to fret about the holy leading part, about declaring what is a "current topic" (sic), etc. Marcosantezana 04:09, 2 February 2006 (UTC)[reply]

Well that sorta explains why the article is the way it is Pete.Hurd 05:17, 2 February 2006 (UTC)[reply]

I'm not saying that all of those things you mention aren't important to the article, they're just not important to the lead section. You're entirely right that the article should not avoid important issues in order to make it accessible, but in my opinion, the lead section should give a clear, concise overview of what natural selection is. After that has been established, the body of the article can go on to talk about the specifics with regards to its history, how it works, and what mechanisms are involved. Keep in mind that anyone who's trained in biology and knows enough about natural selection to understand this article as it currently stands probably doesn't need to read it. The purpose of encyclopedia articles is to educate people who lack a background in the subject, because those who have the background don't need the article. That means it has to be accessible.

I apologize, I seem to have skipped over the definition of fecundity the last time I read the article. I maintain, however, that the lead section is too technical. Even if there is no one word that a layperson could not understand, the section is packed so tightly with long words in long sentences that it just gets overwhelming.

With respect to the "unit of selection" issue, I agree that gene-based selection is a well-established theory. Group selection, however, is not. I think that needs to be made clear. I also still don't think it's essential for the lead section, although I don't feel too strongly about it.

What do you mean by demeaning my status as a biologist? Your argument about why that is meaningless does not relate in the slightest to the context in which I stated it. I was using that to indicate that despite knowing about natural selection and understanding all the words being used, the way in which the sentences were constructed made the article hard to process. You turned that around and told me that people like me know nothing about the subject and need everything explained to us. Please, be civil. I don't mind you criticizing my arguments, but don't attack my intelligence. --Barefootmatt 16:43, 2 February 2006 (UTC)[reply]

so let's play a game. let's make a *list* of what should be in the intro and why?

and let's come up with ideas on how to avoid that people read the pleasant, inviting thing and leave without reading other important stuff. (my trick so far was not to allow anybody to avoid the important stuff)

it's not about intelligence. expertise does equate with intelligence.

"gene-selection"? how about re-reading the useless intro? it's individual selection  ;)

and it's not "well-established" for many traits that are very important. human altruism was evolved via group selection (read the useless intro to see why and also the kin selection article)

see why being a "biologist" does not always help with everything biological?

being civilized when it comes to knowledge implies first and foremost not being overly confident about one's knowledge. smiles and pleasantries and bon mots are welcome but not required.

and i still think the best would be to keep the intro as the only thing and trash everything else . Marcosantezana 04:04, 3 February 2006 (UTC)[reply]

If Marcos is still completely opposed to holding the lead section down to 2-3 paragraphs then I'll continue to direct my efforts to other things. Pete.Hurd 04:40, 3 February 2006 (UTC)[reply]

we are exchanging ideas

the three main problems:

i) to agree on what is fundamental for an educated person to know about selection. ii) how to avoid that the intro, if shortened, be felt as sufficient by people who cannot know better and who will then leave thinking, wrongly, that they got the basics (and then go buy dawkins books), which would mean doing a disservice to them and going against the raison d'etre of wiki. iii) why cannot be the intro the teaser to the reader and catalist and guide to continue expanding the main body of the article.

i propose that we finish, at the highest level of content and readability, the main body of the article, and that we make more readable the intro where needed. Marcosantezana 06:08, 3 February 2006 (UTC)[reply]

• You misunderstood me. In the part about units of selection, I wasn't saying that the article already specifically mentions gene selection. It mentions individual selection, and that there are other levels as well, and it was those other levels that I was discussing. Individual selection and gene selection have, from my POV, been well proven as generalizable models of selection. The consensus seems to be shifting from individual to gene as the basic, universal mechanism, as gene selection explains altruism better than individual selection. Group selection, on the other hand, is generally considered, at least by the people I've talked to, as being "the easy way out" of explaining the real mechanisms of selection. It is fallacious and is supported by not a shred of evidence that is not better explained by gene selection.
• Having now read the kin selection article you directed me to, I can only conclude that we can't possibly be talking about the same thing. What I know of as "group selection" is not used at all in that article. Group selection (read that article) is the theory that members of a population have traits that were selected for the survival or benefit of the population as a whole, rather than the fitness of any individual. Kin selection, on the other hand, is explained by the concepts of gene selection and inclusive fitness. Genes are selected for which increase an individual's inclusive fitness, despite a decrease in its direct fitness; i.e. the gene enhances the survival of close relatives by an amount equal to or greater than the resulting decrease in survival of the individual (taking into account the degree of relatedness as the probability that the individual's genes, especially the altruism gene in question, are found in a given relative). That has nothing to do with "group selection", because none of the effects of the trait are explained solely on the group level. The trait may also increase the overall survival of the population, but stopping there and assuming that the individual is acting purely for the benefit of the group is just lazy.
• I agree entirely with your statement of the problems at hand. Those are exactly the things that need to be addressed, and I'd say that's what we're doing. --Barefootmatt 18:00, 3 February 2006 (UTC)[reply]

unfortunately you cannot only work with what's here in wiki. and i cannot expect you to be a specialist: the sentence "that alleles can become fixed or spread in a population because of the benefits they bestow on groups, regardless of the fitness of individuals within that group" should give you a hint if you compare that to the first sentence in "kin selection". you could read elliott's sober's book "the nature of selection" if you really care about this. it gives the proof that "kin-selection" is a case of group selection Marcosantezana 18:16, 3 February 2006 (UTC)[reply]

The sentence you just quoted and the first sentence in kin selection are not the same thing! What you quoted says that for the alleles in question, the group is the unit of selection. The first sentence in kin selection essentially says that individuals act to ensure the replication of their genes, whether through themselves or through the survival of their relatives. Kin selection generally acts on small family groups, as the degree of relatedness quickly diminishes the inclusive fitness gained with progressively distant relatives. Group selection, on the other hand, is often said to act on the level of whole species.

Would you please stop trying to criticize my expertise? I have done extensive reading on kin selection and eusociality. Don't assume I know less than you just because we disagree. As for "proof", need I direct you to the classic writings of Sherman (1977) and Hamilton (1964)? There's some "proof" for the gene-level basis of kin selection. --Barefootmatt 18:56, 3 February 2006 (UTC)[reply]

"Elliott Sober in his book "The Nature of Selection" has stressed that natural selection can entail the differential reproduction of many things ("selection of") but that it is the cause of the differences in reproductive output what points to the target of selection and thus defines what the level and the unit of selection are." this from the horrible intro should have given you the cue. more in sober's book. see, sober became famous among philosophers of science bcse of his solution to this "unit of selection" mess, a mess that had lasted for decades. read the book or the few web pages that present his arguments clearly. reading naive biologists' puerile attempts at analytical philosophy just won't do. yes that includes lewontin, maynard smith, gould, williams, you name them. Marcosantezana 19:23, 3 February 2006 (UTC)[reply]

Perhaps you're right about Sober, but I'm not convinced, and other readers won't be either. Readers of an encyclopedia shouldn't have to go find another book to find the reasoning behind your arguments. I'm not sure what the sentence you quoted is trying to say (is the "what" after "reproductive output" supposed to be "that"? Even then it doesn't really make sense), but it seems like it's trying to say that Sober believes that selection can take place at different levels. That's fine, but it should also say why he thinks that. Giving the name of an expert on the subject does not excuse us from explaining why that perspective is the right one. --Barefootmatt 20:16, 3 February 2006 (UTC)[reply]

the cause of the differences in reproductive output is what points to the target of selection and thus defines what the level and the unit of selection are... and this cause is not to be confused, if i may add, with whatever caused each individual involved to become different as it developped from egg to adult Marcosantezana 20:36, 3 February 2006 (UTC)[reply]

Guys, whatever happened to being bold? We've had lengthy discussions like the one above over at evolution and they actually resulted in very little change. I think we all agree on a few things, e.g. the material in the lengthy introduction must be dispersed to other, possibly new sections and articles. Can we just go ahead and do this? - Samsara _contrib ^talk 11:52, 9 February 2006 (UTC)[reply]

Samsara, please go do it. I think the consensus is close to but not quite at unanimity on what needs to be done. I'm up to my eyeballs in midterms, various manuscript deadlines (and an infant that appears to be member of some sort of cult opposed to any and all sleep on anyone's part), but I'll be checking in a couple of times a day at least to lend help on details and other issues. Bold on! Pete.Hurd 15:31, 9 February 2006 (UTC)[reply]

i think the critical issue here is to agree on what is important for people to read first. be bold, go for action, say what it is important for people to read first before messing things haphazardly. in other words be bold but be also serious. i alredy wrote this before but people prefer "action". what's this futurism? fascism? Marcosantezana 06:08, 10 February 2006 (UTC)[reply]

Well, I am particularly in favour of changing things that are factually inaccurate, such as the statement that Darwin was the first to discover NS. The introduction is meant to be just that, an introduction to the article and its different sections. The introduction is still trying to be an article unto itself, as you've pointed out yourself. However, it is clearly not sufficient as an article, so let's go and shake out the dirt, and return to the talk page if disagreements happen - I take it they haven't happened yet? If so, please say. - Samsara _contrib ^talk 11:38, 10 February 2006 (UTC)[reply]

don't see where in the intro darwin is said to be the discoverer. however, what matters is both intellectual impact and primacy. darwin's impact cannot be denied, primacy is often important for the celebratory phase of a community. nothing against it, but primacy without impact belongs best in the history part.

btw, i think that your idea of reallocating things is sound as long as we manage to get a very short intro paragraph that won't allow people to walk away misinformed (like that in muller's ratchet, or the first sentence in kin selection). however, some people like it quick so the intro stuff could become a kind of executive summary/overview (like a micropedia article in britannica albeit with more substance) that precedes the table of contents. Marcosantezana 16:25, 10 February 2006 (UTC)[reply]

• The introduction is waaaaaay too long and way outside the boundaries of our Manual of Style. The intro should contain: 1. a very, very brief (one, two sentence max) definition of what natural selection is; 2. a super-brief history of the term (Darwin, theory of evolution, wasn't popular, then with modern synthesis became important again). The rest of the article should deal with these two issues (defining it, the history of it). Simple as that. --Fastfission 01:09, 12 February 2006 (UTC)[reply]

• As an aside, the list of tasks above says merging from the 1911 EB is still needed. I'm highly suspicious that it is. For one thing, the theory of natural selection was in a vastly different position in 1911 than it was by the end of the 1930s, much less today. I would be highly suspicious that an entry on the subject made in 1911 would be accurate today. --Fastfission 02:14, 12 February 2006 (UTC)[reply]

Dear All,

I felt it was a good idea, in the light of our attempt to bring down the size of the intro and get this article to FA standard, to move a section dealing with Elliott Sober's contribution to the unit of selection debate to that more specific article. I have noticed that my change has been reverted. The section now exists in duplicate, once at unit of selection and once here. Can we reach a consensus on where it belongs? Let's hear your views. Thanks. - Samsara _contrib ^talk 13:28, 12 February 2006 (UTC)[reply]

I really like the idea of having an article to cover this topic, the coverage in this article is a bit opaque and a lucid treatment of the issue would be really valuable. I'm not totally opposed to having some dupication here in Natural selection, but not in the lead section (as I've said a here a couple of times before). I think a brief (one short paragraph) section or subsection with a link to the main article is the way to go. Cheers, Pete.Hurd 16:52, 12 February 2006 (UTC)[reply]

i'd recommend that you all truly reflect on this issue. if that does not help, i think that you should read sober's book. this is not a side-issue, this is about the very essence of what selection is and what is not, and is very important because grasping this allows one to avoid confusing selection and evolution by selection and the many confusions that arise when people do that (e.g. group vs. kin "selection") Marcosantezana 18:43, 12 February 2006 (UTC)[reply]

I'm with Samsara; the material should be moved. The paragraph that remained still described the issue briefly and provided a link to unit of selection for elaboration. On a side note: Marcosantezana, please make use of the "Edit Summary" feature. This is especially important when you're reverting changes someone else has made. To indicate a reversion, include the word "revert" or "rv" in the edit summary, preferably with a section heading and/or some indication of what is being changed and why. --Barefootmatt 02:13, 14 February 2006 (UTC)[reply]

i do use that edit summary thing, dear barefoot, and i did not "revert". i edited the passage. do yo want me to lie?  :( furthermore, i'd like to read your arguments rather than learn how much and/or strongly you agree with others. ever read sober's book? do you know why he has gotten so many prizes? do you know his main arguments? anything to say about why his arguments deserve or not to be included in the article ? sober's identification of the causation of fitness differences as the sole criterion to decide on units of selection/level of selection issues is the major advance of the last 50 years in the analytical philosophy and epistemology of natural selection and, as a i wrote above, provides the foundation to avoid common and pernicious misunderstadings about selection by both aficionados and professionals.  ;) 03:24, 14 February 2006 (UTC)

Hi there, the header says it all: if I remember correctly, the irony of the Origin was that it does not make a link between natural selection and speciation. Hence, we can shorten the intro from

Natural selection is the metaphor Charles Darwin used in 1859 to name the process he postulated to drive the adaptation of organisms to their environments and the origin of new species.

to

Natural selection is the metaphor Charles Darwin used in 1859 to name the process he postulated to drive the adaptation of organisms to their environments.

Correct? - Samsara _contrib ^talk 18:40, 12 February 2006 (UTC)[reply]

...although he may have done in subsequent publications? - Samsara _contrib ^talk 18:44, 12 February 2006 (UTC)[reply]

be this as it may, darwin did not "forget" the origin. it is obvious that he knew that one needn't be a rocket scientist to figure out that populations would diverge adaptively and become different species. are we kidding here? are we all bookish sophists? to the very least one should write that the origin followed from his treatment of adaptation. and the mere title justifies one saying that he proposed selection as the driver of speciation. Marcosantezana 18:51, 12 February 2006 (UTC) 18:50, 12 February 2006 (UTC)[reply]

• My understanding of Origin is that the mechanism CD proposed that the combination of NS with natural variation and lots and lots of time was indeed what brought about new (that is, divergent from previous and other) species. But he was fuzzy about whether NS brought about new species or whether it merely selected them for survival. One line from Origin which I hope is not too much of a quote out of context: "...I think it inevitably follows, that as new species in the course of time are formed through natural selection, others will become rarer and rarer, and finally extinct."[2] (emp. mine) --Fastfission 21:20, 12 February 2006 (UTC)[reply]

It seems like that quote is addressed more to chronospecies than what we would now call allopatric speciation. Also, I think it was implicitly acknowledged by the founders of the modern synthesis that Darwin really didn't solve the problem of the origin of species more generally (which is why there are so many books entitled something and the origin of species). And yet, as that quote shows, Darwin certainly made some connections between natural selection and speciation.--ragesoss 22:27, 12 February 2006 (UTC)[reply]