Talk:Punctuated equilibrium

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Good article Punctuated equilibrium has been listed as one of the Natural sciences good articles under the good article criteria. If you can improve it further, please do. If it no longer meets these criteria, you can delist it, or ask for a reassessment.
June 27, 2007 Good article nominee Listed
Peer review This article was externally reviewed (December 14, 2005) by Nature. No significant errors or major omissions were found.
Charles Darwin This article is part of WikiProject Evolutionary biology, an attempt at building a useful set of articles on evolutionary biology and its associated subfields such as population genetics, quantitative genetics, molecular evolution, phylogenetics, evolutionary developmental biology. It is distinct from the WikiProject Tree of Life in that it attempts to cover patterns, process and theory rather than systematics and taxonomy. If you would like to participate, there are some suggestions on this page (see also Wikipedia:Contributing FAQ for more information) or visit WikiProject Evolutionary biology.
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[edit] Jerks and creeps

This addition:

evolution by 'jerks and creeps'? is this vandalism or is it really what biologists refer to it as?

by 58.28.156.83, (the latest adddition), Totally addressess my complaints, about "Punctuated equilibrium"(The Article (in wikipedia)) --22:10, 6 December 2006 (UTC)

  1. "Jerks and creeps" –Just a historical part of the definition (?), and is probably pretty much a "skewed" way of analyzing or interpreting this very important concept (of rapid movements of change), (analagous to another concept of: Saltation, recently split by wikipedians, but missing the whole darn point of what satltation implies: a steady–state condition immediately (in a short time) ending at a different steady-state condition.)
  2. Just because the historical part of how this term: Puntuated Equilibrium arose, fits into some new thinkings, or definings of our world, doesn't mean that "We" have it accurate, ... or that it actually is defined well (defined well= defined Not-poorly).
  3. When even looking at the articles-(and the associated articles like Darwin's finches, or Charles Darwin Research Station) for the Galápagos Islands in wikipedia, they mention seeing the "evolution", the changes right in front of them, It pretty much shows that the "time-frames", and that reference-points to time changes, (w/ envionmental condition changes), are all only surmised, or guessed. When I first heard of the term "punctuated equilibrium", I knew finally that the correct term had finally been found. Having studied, or having seen data, on so many interesting "natural selection" species, types, etc., I was so glad that a "correct-term", more appropriate term had been found.
  4. for the above short reasons, (and confer with the concept: Saltation), understand that we can have an article that helps define "Punctuated equilbrium", but even the first sentence in the article may be poor, (or even incorrect in its statement). (I believe the first sentence has "Mis-statements")

So lets just continue on, (and please bypass the puns about the "jerks and creeps", and sometimes notes by the ....people who have another idea). Comments from the ArizonaDesert...--Mmcannis 22:10, 6 December 2006 (UTC)

"Evolution by Jerks". the 'creeps' who coined this phrase never considered the Harm they could do, to trying to understand the the Mechanisms of Evolution. Every, all changes both rapidly and slowly, only the Timeframe is the lens that determines which change is quick, (snap of the finger) of Slow, (Glacial-ly slow). Any way, i personally have always been offended by the Phrase, because it Belittles how difficult it is to organize how changes actually do occur in All Scientific fields over the Time Changes. As for Biology: Thank goodness for Cladistics. (from the SonoranDesert ofArizona-) -Mmcannis 15:59, 27 January 2007 (UTC)

[edit] Archiving. Also, the article is too wordy.

Just cleaning up and archiving here. *swings his feather duster around gaudily*

By the way, the depth of understanding that this article assumes varies, but worse off, the average knowledge on the subject assumed is too deep itself. There are plenty of people out there who want to know what Punctuated Equilibrium is who haven't taken ecology courses, or took their last one a few decades ago. Most people don't know what sympatric, allopatric, and destabilising selection (forget if that's what you call it) are. And they don't want to have to read through 80 links to be "qualified" to read this article, so the solution isn't to put up more links.

This article needs to be put in plain English, boys.

Anyone here who knows the basics of ecology: break down some of the scary words into layman's English. Easy up the language. If you think this current bookish version is too educative to dumb down, move parts of it to the ecology wikibook before you dumb the article. But it does need to be dumbed down in some places (specifically the first three sections.. it seems to get a little easier after that).

Don't forget, your audience is a bunch of people who barely understand what evolution is. You don't need to cater to the ignorant (you don't need to re-explain evolution here), but at least allow them to eat at the table with you (make it so they can follow along).

-Monk of the highest order 06:28, 16 November 2006 (UTC)

[edit] Acquiescence?

Under "Punctuated Equilibrium's History," is "acquiescence" the correct word or should it be "acceptance" or something else?
Monado 11:32, 27 July 2007 (UTC)

[edit] relation to darwinism

I think that this section is somewhat misleading, or at least incomplete. Despite of the Darwin quote stressing the importance of the large areas, and demining somewhat the importance of isolation, "darwinism" as it is known didn't stop with Darwin (which barely knew mendelian genetics, and probably (my guess) haven't taken it into consideration at all), and with the modern synthesis (by 1930, about 40 years before PE), the aggregation of populational genetics with neodarwinism, the importance of peripheral isolates is at least implied, but was even stressed by some, such as Sewall Wright with his shifting balance theory of evolution, and Ernst Mayr emphasized the importance of allopatric speciation, isolation implied.

But also, the quotation in that context constrasts somewhat artificially Darwin's views with PE and its precursors. Much of what he is saying in the quotes, could be recontextualized and seen as an example of how he anticipated not only peripheral isolation as important for species formation, and also the species substitution (and species selection) of PE, to which, I think, isolation is also a hinderance. --Extremophile 06:17, 7 September 2006 (UTC)

[edit] FYI addition to Influenzavirus A

Researchers from the National Institutes of Health used data from the Influenza Genome Sequencing Project and concluded that during the ten-year period examined most of the time the hemagglutinin gene in H3N2 showed no significant excess of mutations in the antigenic regions while an increasing variety of strains accumulated. This resulted in one of the variants eventually achieving higher fitness, becoming dominant, and in a brief interval of rapid Darwinian evolution rapidly sweeping through the human population and eliminatimg most other variants.[1]

WAS 4.250 22:58, 27 October 2006 (UTC)

[edit] Biased article - More Criticism of Punctuated equilibria position needed

I believe if the material below were incorporated in the article it would make it less biased.

First, I found the following quote: "Although uncertainty exists about just how recently the pairs of species diverged and about the relation between range and population size, Anderson and Evenson's data does not support Eldredge and Gould's claim that speciating populations are very small." —*Mark Ridley, "Evolution and Gaps in the Fossil Record," in Nature 286(5772):444-445 (1980). *Anderson and *Evenson did a 1978 study on geographic ranges of North American species which are supposed to have diverged recently.] [1]

I also found this material criticizing punctuated equilibrium: "But why do proponents of the punctuated equilibrium theory insist so much on the concept of restricted populations? The reason is clear: Their aim is provide an explanation for the absence of intermediate forms in the fossil record.

However, scientific experiments and observations carried out in recent years have revealed that being in a restricted population is not an advantage from the genetic point of view, but rather a disadvantage. Far from developing in such a way as to give rise to new species, small populations give rise to serious genetic defects. The reason for this is that in restricted populations individuals must continually mate within a narrow genetic pool. For this reason, normally heterozygous individuals become increasingly homozygous. This means that defective genes which are normally recessive become dominant, with the result that genetic defects and sickness increase within the population.178

In order to examine this matter, a 35-year study of a small, inbred population of chickens was carried out. It was found that the individual chickens became progressively weaker from the genetic point of view over time. Their egg production fell from 100 to 80 percent of individuals, and their fertility declined from 93 to 74 percent. But when chickens from other regions were added to the population, this trend toward genetic weakening was halted and even reversed. With the infusion of new genes from outside the restricted group, eventually the indicators of the health of the population returned to normal.179" [2] ken 11:35, 19 November 2006 (UTC)kdbuffalo

  • Will you please stop spamming ridiculous POV tags. The article is fine at its core, and the two sources you cite fail WP:RS with blazing colors. *Spark* 14:33, 19 November 2006 (UTC)
Removed tag. Just because your creationist POV doesn't fit the article does not mean the article has a problem. POV trolling is the problem. Vsmith 15:46, 19 November 2006 (UTC)
Are Nature and Science forbidden journals to allude to. Because that is what was alluded to here. Putting back POV tag. ken 17:35, 19 November 2006 (UTC)kdbuffalo
You didn't cite Nature and Science. You cited second hand creationists who cite Nature and Science. We've been over this before. They aren't WP:RS and that isn't acceptable. And once again the sources are way out of date. In this case at 26 and 28 years out old they are even more out of date than the ones you wanted to put on the Dawkins page. Now stop, this is getting to be disruptive. JoshuaZ 18:18, 19 November 2006 (UTC)
Disruptive to what? Disruptive to your desire to have biased articles that are propaganda pieces for the evolutionary position? Articles should be NPOV. ken 18:26, 19 November 2006 (UTC)kdbuffalo
Regarding the issue of small population - this illustrates the problem with quote mining quote miners. To begin with, the article was about prairie chickens, not chickens. It appears that the author of "darwinism refuted" doesn't realise that there's a difference between the two. If you actually look at the article, Illinois populations declined from "possibly several million prairie chickens statewide in the mid-19th century" to 2000 birds in 179 populations, to 46 birds in two populations in 1994. So this isn't an article about small populations, it's an article about precipitously declining populations. And that makes a huge difference. Large populations can tolerate fairly large genetic loads. However, when individuals are moved from large populations to small populations, you now have a much higher probability of deleterious alleles coming together (see inbreeding depression). This isn't the case in populations which were small to begin with (or which declined gradually). In cases like that, the genetic load is lower to begin with, so they are more tolerant of inbreeding. Taking one of the most extreme examples (millions to dozens in a century) and trying to generalise it to small populations in general is dishonest. Which, again, leads back to the issue of why you should not quote second hand sources. Guettarda 13:32, 20 November 2006 (UTC)
Regarding the Ridley reference - I don't see how Ridley's statement, from a quarter century ago, which says that Anderson and Evenson's data did not support punctuated equilibrium somehow makes this article non-neutral. The intro to the article contrasts PE with gradualism, and even a cursory glance down the article shows a criticism by Dawkins. So what about the article is non-neutral? Eldridge and Gould proposed to idea to explain trilobites. Anderson and Evenson, according to your source, looked at species which diverged recently. While I don't have a context for what Ridely said, I suppose given that there was still a fairly polarised debate regarding PE back in 1980, it may have been worth pointing out. But, to the best of my knowledge, no one is saying that PE applies in all cases, but rather than it may apply in some cases. Anyway, I still don't understand what any of this has to do with NPOV. Guettarda 13:52, 20 November 2006 (UTC)

[edit] The following critique of the punctuated equilibrium hypothesis should be incorporated in the article

I think the following article clarifies matters further: Punctuated equilibrium: come of age? by Dr Don Batten 136.183.146.158 00:50, 26 November 2006 (UTC)

Can you stop spamming AiG links? I'm failing to see how a "Creationist Agricultural Scientist" can be taken seriously in any meaningful scientific context. *Spark* 02:50, 26 November 2006 (UTC)
I thought the article was quite informative and would give some needed balance to the Wikipedia article. 136.183.146.158 03:00, 26 November 2006 (UTC)
Well Ken, you're wrong. The article is basically balanced as it is, and input from someone who has no business commenting in a scientific article is not warranted. *Spark* 03:23, 26 November 2006 (UTC)

(reset indet) For others reading this and wonder where the heck "Ken" came from, we're suspicious that the IP address 136.183.146.158 is being used by someone called ken/kdbuffalo. See http://en.wikipedia.org/wiki/Wikipedia:Requests_for_comment/Kdbuffalo_2#Evidence_of_disputed_behavior for more and make your own mind up. Pity really as I thought we had someone new, with new ideas and not just the same old stuff. Ttiotsw 05:34, 26 November 2006 (UTC)

[edit] GA Re-Review and In-line citations

Members of the Wikipedia:WikiProject Good articles are in the process of doing a re-review of current Good Article listings to ensure compliance with the standards of the Good Article Criteria. (Discussion of the changes and re-review can be found here). A significant change to the GA criteria is the mandatory use of some sort of in-line citation (In accordance to WP:CITE) to be used in order for an article to pass the verification and reference criteria. Currently this article does not include in-line citations. It is recommended that the article's editors take a look at the inclusion of in-line citations as well as how the article stacks up against the rest of the Good Article criteria. GA reviewers will give you at least a week's time from the date of this notice to work on the in-line citations before doing a full re-review and deciding if the article still merits being considered a Good Article or would need to be de-listed. If you have any questions, please don't hesitate to contact us on the Good Article project talk page or you may contact me personally. On behalf of the Good Articles Project, I want to thank you for all the time and effort that you have put into working on this article and improving the overall quality of the Wikipedia project. LuciferMorgan 02:21, 16 December 2006 (UTC)

[edit] Result of the GAR

[edit] Punctuated equilibrium

result:No consensus (leaning toward keep) 3-3

Warned by me 5 weeks ago regarding lack of inline citations. Delist. LuciferMorgan 02:17, 25 January 2007 (UTC)

  • Delist, no inline cits. Kyriakos 03:01, 25 January 2007 (UTC)
  • Keep , this is silly, the Wikipedia:Harvard referencing is completely acceptable on Wikipedia. / Fred-Chess 13:12, 26 January 2007 (UTC)
  • Comment The referencing doesn't even state what it's specifically referencing. Also, WP:WIAGA requires some form of inline citation. LuciferMorgan 14:48, 26 January 2007 (UTC)
  • I'm sorry, but I don't understand what the problem with the article is... / Fred-Chess 09:53, 27 January 2007 (UTC)
  • Keep I'm not claiming this is a perfect article content-wise, but to delist it because it uses Harvard referencing - which is a form of inline citation - would be silly. Opabinia regalis 05:16, 28 January 2007 (UTC)
  • Keep per Opabinia regalis. Could possibly use some diagrams. - Malkinann 06:16, 29 January 2007 (UTC)
  • Can't someone convert the Harvard referencing then? LuciferMorgan 03:20, 30 January 2007 (UTC)
    • Why does it need converting? (And what to?) Harvard referencing is a perfectly acceptable form of inline referencing on Wikipedia. Converting the article's referencing system without the consensus of the editors of the article is also discouraged in WP:CITE. - Malkinann 04:24, 30 January 2007 (UTC)
      • Convert to cite.php. Or at least have the Wikipedia templates for Harvard referencing, like {{ref}} and {{note}}. Hbdragon88 22:49, 31 January 2007 (UTC)
Conversion to Cite.php would be a lot of work, especially as Harvard referencing is a perfectly acceptable form of inline referencing on Wikipedia. I've put a proposal up on the associated wikiproject to change the method of citation from plain Harvard to Harvard with templates, as seen in Charles Darwin. But without consensus on this change from the wikiproject, I am reluctant to do so myself, as I've previously had very little to do with this article. -Malkinann 23:37, 31 January 2007 (UTC)
Hold on a minute, "Awaiting consensus"? Many GA reviews end with no consensus at all, and this looks like a 3 to 2 vote. Homestarmy 20:39, 7 February 2007 (UTC)
I count 3-3. - Malkinann 08:29, 8 February 2007 (UTC)
  • Delist External jumps, the 3 inline references aren't formatted correctly, does not conform with WP:MOS. M3tal H3ad 08:46, 8 February 2007 (UTC)
  • Delist Per above (reference formatting, lack of conformity). I can't support an article when someone who wishes to keep it says "I'm not claiming this is a perfect article content-wise". If it's not better than the average article, why make it good? A little work on the article and they can easily re-nominate it. Nja247 (talk • contribs) 00:14, 9 February 2007 (UTC)
It is better than the average article. Two years ago, it was checked by the Nature journal and found to be a pretty good article, with no glaring omissions. Isn't there no such thing as a perfect article, anyway? -Malkinann 07:34, 9 February 2007 (UTC)
  • First of all, it should be noted that footnotes can not necessarily be replaced by Harvard references, because footnotes are not always references. However, in this article I do think that the inline citations can all be converted to the harvard references. Why not convert all to Harvard references if you think it is too much work to convert them to cite.php? / Fred-Chess 12:29, 10 February 2007 (UTC)
Ok, I'll give it a go. :) -Malkinann 04:39, 11 February 2007 (UTC)
I've been bold and changed the footnotes to Harvard citation.-Malkinann 06:23, 11 February 2007 (UTC)

[edit] Just a quick question!!

I don't want to sound like I'm stupid or something but could someone clear it up for me... if like a bird hatched from a lizard egg or something and flew off happily ever after, what would it mate with to, erm, make more birds? Thanks!! hope I didn't sound entirely naive or anything LOL 24.231.209.204 23:26, 21 February 2007 (UTC)

Could you guys answer real quick i have a paper to write -- 24.231.209.204

Wikipedia talk pages are not the place to ask questions about the subjects of their associated articles. That being said, the process you described is called saltation, and it doesn't actually happen. Every offspring is the same species as its parent, and they turn into different species slowly over many generations. Consider reading the TalkOrigins article "Introduction to Evolutionary Biology" before writing about the subject, and please don't use Wikipedia talk pages for this purpose. -- Schaefer (talk) 04:53, 28 February 2007 (UTC)

My apologies, then. 24.231.209.204 19:36, 15 March 2007 (UTC)

[edit] Controversy

I will start by saying that I am a supporter of the Modern evolutionary synthesis and an opponent of Intelligent design. However, I believe that the theory of punctuated equilibrium is deeply flawed. Daniel Dennet (well-known as a supporter of Darwinian evolution and atheism) gives a harsh criticique of punctuated equilibrium in Chapter 10 of Darwin's Dangerous Idea. I was surprised that there is no discussion of the controversy in this Wikipedia article. See Dennett's book for further references.--Pdturney 00:48, 2 March 2007 (UTC)

Daniel Dennet's criticism amounts to "what's the big deal?" I imagine it would be difficult to incorporate this "argument" into the body of the article. Miguel Chavez 06:59, 6 April 2007 (UTC)
Your summary of Dennet is accurate but simplistic. "What's the big deal?" is a valid question. And it's a question that Gould was unable to answer. --Pdturney 02:38, 7 April 2007 (UTC)
Of course. But there is a curious aspect of evolution called tempo. For those who study evolution, they are very curious as to how the tempo of evolution behaves. Does it behave uniformly, or on multiple levels? Is it slow, or fast, and is it gradual or sporadic? Paleontologists who study this phenomenon have wondered about the tempo of change even before Darwin published his Origin of Species, and for them--and really for anyone who has an honest curiosity about the nature of evolution--they wonder about such things. Eldredge and Gould proposed a novel answer to this problem (by combining several theories, and applying new statistical techniques to the empiric's of paleontology). They challenged their colleagues to look at their data in a completely inverted way. So for some, this idea might be worthy of some attention. But if you don't care about such things, and all you care about is adaptation, I can see why you might throw your hands up and say "what's the big deal?" Miguel Chavez 07:17, 7 April 2007 (UTC)
I think that Dennet and Dawkins would agree that the issue of tempo is interesting, but argue that Eldredge and Gould do not shed light on the issue; rather, they confuse the issue. --Pdturney 14:41, 7 April 2007 (UTC)
Regarding your latter statement, Dawkins has said just the opposite in The Extended Phenotype (p. 101), and Dennet (I'm not quite sure what particular statement you're referring to) is not remotely qualified to offer an opinion one way or another. He simply has no grasp of the paleontological literature. Best, Miguel Chavez 15:43, 7 April 2007 (UTC)
"What needs to be said now, loud and clear, is the truth: that the theory of punctuated equilibrium lies firmly within the neo-Darwinian synthesis. It always did. It will take time to undo the damage wrought by the overblown rhetoric, but it will be undone." (Dawkins 1986)--Pdturney 21:13, 7 April 2007 (UTC)
Well I agree with Dawkins, but so does Gould. The problem arises when people like Dennet run their mouth and haven't a clue to what they're talking about. When Gould says punctuated equilibrium challenges neo-Darwinism, he means its commitment to gradualistic modes of change. Even Dawkins admits that stasis was unexpected (p. 243). If this article has a problem, and it has many, it stems from a lack of disscussion of the "species as individuals" hypothesis, variable speciation rates, and its implication for a hierarchical theory of selection, etc. If I were you, I would read Gould's original papers, as many as you can, read some of the major reviews (Mayr, Ruse, etc.) and then, and only then, make up your mind. I too started with Dennet and had to work my way out. Best, Miguel Chavez 01:29, 9 April 2007 (UTC)
I've read several of Gould's books (Ontogeny and Phylogeny, Ever Since Darwin, The Panda's Thumb, Wonderful Life, Full House, The Structure of Evolutionary Theory) and several reviews of Gould (Dawkins, Dennet, Papineau, Tooby and Cosmides, Wright, Ruse, Alcock). I agree completely with Dennet's conclusions about Gould in Darwin's Dangerous Idea. It's clear that you and I are not going to agree on Gould, but I think we can agree that this article needs to discuss the controversy in more detail. --Pdturney 15:12, 9 April 2007 (UTC)
Gould's books are a great start, but I meant his original technical papers. And by reviews, I meant both sides of the controversy, and those written by professionals who know what they're talking about. For example, a list of competent critics would include names like Maynard Smith, Stebbins, Gingerich, and Ridley; not Dennet. Best, Miguel Chavez 04:26, 10 April 2007 (UTC)
Lastly, I agree with you on the need to expand on the controversies section, but I don't have the time right now to go through the literature and write up summaries. If you wish I can help you incorporate some of the arguments into the article, in fact, I would be more than happy to do this, but I need to know what criticisms you have in mind (short of Dennet's antipathy). Best, Miguel Chavez 15:27, 10 April 2007 (UTC)
On your advice I incorporated a detailed summary of Dawkins' critique, as expressed in his Blind Watchmaker. There will be more will come as time permits me. Miguel Chavez 02:58, 18 April 2007 (UTC)
Good summary! --Pdturney 12:45, 18 April 2007 (UTC)
Thanks! Miguel Chavez 17:28, 20 April 2007 (UTC)
After having gone back and reread Dennett, I now regret my remarks (with regards to Dan's section on punctuated equilibrium). His analysis is actually quite reasonable, and it is obvious to me that he has taken his time to read the original papers carefully. My apologies, I was brash and unfair. But I think you overestimate Dennett's arguments here. He actually holds a very moderate opinion on the whole issue of Punc Eq. It is far less extreme than the rest of Dennett's book. Best, Miguel Chavez 05:24, 27 April 2007 (UTC).

[edit] Outlining

This article lacks a proper and coherent outline. I've cleaned it up a little, but I was thinking of something along the lines of:

  • Introduction
  • Brief History
  • Mechanisms
  • Tempo and Mode Before 1972
  • Pre-Darwin
  • Charles Darwin
  • 1859-1930s
  • Neo-Darwinian Synthesis
  • Summary of 1972 Paper
  • Reception
  • Summary
  • Positive Reception
  • Detailed list of supporters (possibly in an endnote)
  • Critical Responses
  • Richard Dawkins
  • John Maynard Smith
  • Francisco Ayala
  • Daniel Dennett
  • Philip Gingerich
  • Detailed list of detractors (possibly in an endnote)
  • The Tri-fold history
  • Popular Press
  • Creationists
  • Alternative Support
  • Neo-saltationism
  • Complexity theory
  • Species as individuals
  • Michael Ghiselin and David Hull
  • Gould and hierarchy

Any suggestions would be more than welcome. This list, if implemented, will demand much more work from contributors. Best, Miguel Chavez 03:17, 18 April 2007 (UTC)

[edit] Intro

Most of you who edit this article and such probably already knew what it was so it might be hard to tell. But to someone like me who has no clue what it's about and is just reading it to understand a term from Science class the introduction is very confusing. A lot of terms in that intro that I don't understand, maybe links to an article that explains what they mean would help while a few of the sentences aren't that clear. Just some suggestions. Thanks! Deflagro C/T 01:47, 20 September 2007 (UTC)

I think Deflagro is onto something. The first sentence of the intro is not the right lead for the section. I don't trust my own editiorial powers in this subject area, but I may take a run at it. This should be viewed as a threat because I might botch it. DCDuring 03:11, 20 September 2007 (UTC)
While I hope I've made a small improvement, the lede could be further improved. Verisimilus T 10:09, 20 September 2007 (UTC)

Imported from User_talk:Verisimilus Verisimilus, I like most of your changes to the intro to the article on Punctuated Equilibrium but I wanted you to reconsider one in particular. I am not a bilogist but more of a social scientist so I might be interpreting your changes incorrectly but when the original text described evolution as taking place "in rapid bursts, separated by long periods of stasis, in which little change occurs," I thought that it communicated very well the idea that change happens but not in a progressive way. On the other hand, your new text seems to imply, directly, that punctuated equilibrium states that no change happens, period. I am interpreting this correctly? Do we need to go back to the previous text? Jsarmi 15:04, 16 October 2007 (UTC)

I hope to have addressed this point. Verisimilus T 17:23, 16 October 2007 (UTC)

[edit] Gersicks

Would anyone object to the insertion of a paragraph on gersick punctuated equilibrium model of group development into the social theory section. Its explained pretty well on http://www.misrc.umn.edu/workshops/2006/spring/alan.pdf if anyone want to have a look. So let me know, an addition to this article or a seperate article?

Oops, I didn't see this note when I added the paragraph under "applications to social theory". See if you like it. Based on the PDF maybe a bit more detail might be good but I wanted to stay away from a in-depth discussion because I thought that the article should be accessible enough for people to grasp the general biological idea and some of the applications outside of biology/evolution. Jsarmi 15:38, 16 October 2007 (UTC)

Be bold! Go ahead and get stuck in! You can edit where you like and let the bureaucrats worry about the best place to put it later. Verisimilus T 18:29, 16 October 2007 (UTC)

[edit] Question on diagram description

The comments with the diagram at the top of the article has the tag "verification needed." The tag raises the question "Doesn't genetic change count?"

Of course genetic change counts -- I suppose there could be only little morphological change without genetic change. But, didn't the idea for Punctuated Equilibrium come from looking at the fossil record? It is notoriously hard to obtain genetic information from a fossil.

Also, the ideas for taxonomy, the relationships of species, the "tree of life" predate our ability to analyze genetics. SlowJog (talk) 02:09, 15 February 2008 (UTC)

I think the question I was trying to raise was whether punctuated equilibrium was a consequence of long periods of underlying genetic change, expressed in a sudden burst of morphological variation - as the image caption implies - or whether both genes and mophology undergo a rapid change at once, as I understand the hypothesis to suggest. The hypothesis can be (and I think has been) tested in recent groups for which DNA is available, although the details desert me. Verisimilus T 11:11, 15 February 2008 (UTC)
I didn't interpret the diagram & caption to imply anything -- one way or another -- about the underlying genetics. I simply see the intent of the diagram's creator to illustrate in a simple manner the difference between phyletic gradualism and punctuated equilibrium. SlowJog (talk) 17:28, 16 February 2008 (UTC)
It would be interesting if someone were to add more information about the underlying genetics in the article, though. SlowJog (talk) 17:33, 16 February 2008 (UTC)