Talk:Macroevolution

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[edit] Comments from 2004

The biggest questions I have about this concept is are:

  1. Is macroevolution intended to mean a single big change that happens, or rather a series of microevolutions that when added up result in macroevolution?
  2. Why do the small changes not, over time, add up to a big one?
  3. How many microevolutions do there have to be before it becomes a macroevolution?
  4. Do creationists accept that most microevolutions are going to be harmful, but a few are beneficial?
  5. Do creationists accept that the beneficial microevolutions can replace the original organism (survival of the fittest)?
  6. How, within this theory, is a species defined? As two groups that can not breed?
  7. If so, what about organisms that do not have sexual reproduction (e.g., bacteria)?


I think these issues should be addressed in the article. --Dmerrill

I'm new to this article, so I won't edit it directly right now, but I'll answer some of your questions:

1) Macroevolution is distinguished from microevolution because it is different than just "a lot of microevolutions". Those who think that "macroevolution" is just the sum of many "microevolutions" don't use the terms...to them it is all just "evolution" and the same mechanisms work at all scales, from sub-species all the way to domains.

2) This is not just a debate between scientists (Darwinists) and creationists. There are several scientists who are just as Darwinist as anyone else, yet they believe that macroevolution must occur by different mechanisms than microevolution. One of my professors portrays it as a debate between population geneticists (who see all evolution as being equivalent) and developmental geneticists (who distinguish between micro and macro). He thinks this issue is very important, and he is going to address it at the end of this semester. I'll return in a month or so after I've studied it more.

--adam

Based solely on the article, it seems to me that "macroevolution" is not a theory at all but a concept, and that the conceptual distinction between micorevolution and macroevolution is important in the theory (or theories) of "intelligent design." If I am correct, the article should be changed. If I am incorrect, I for one would appreciate the article making the point clearer and explaining the theory (as opposed to the concept).

By the way, this conceptual distinction relies on an underlying assumption about the nature of "species." Darwinian evolutionary theory does not make this distinction largely because it views species more as statistical rather than ontological phenomena. The diference between how Darwinianists and non-Darwinianists view "species" is central to understanding why Darwinianists do not distinguish between micro and macro evolution, and why non-Darwinianists do, so I think the article would be improved if this underlying view were explained.

Although I am willing to do this myself I'd like to invite those who have already been working on the article to respond/try this first, SR

Seeing that this page largely recaps discussion held on other pages (such as the evolution page) and really needs discussion in the broader context of evolutionary theory rather than as a standalone topic, I would argue that this page should basically point to the relevant other pages. --Robert Merkel

I disagree -- there is much to be said about macroevolution which isn't really useful in the evolution article. My general biology textbook has several chapters that is mostly on macroevolution. --mav

Anyway, macroevolution and microevolution should definitely be combined into one article. These concepts are as interconnected as light and dark. --adam

Can I ask, why aren't there any arguments for or against macroevolution in this article? I'm not a creationist, but I'm not an evolutionist, either. Why are there no arguments for or against it?

The link to the '29+ evidences for macroevolution' had a critique written which was described by the original authour as "well-written, very thorough, and quite lengthy (the criticism is longer than the original article)". I linked both the critique and the critique of the critique!

Can I note that from a philosophy of science perspective, scientific dismissal of creationism as 'untestable' is a good demonstration of why science is open to postmodern critique and shouldn't be seen as telling absolute truth. Science has developed rules to determine whether or not knowledge is 'scientific', such as repeatability, testability, disprovability and thus religious knowledge and belief is inherently unscientific by the definition of the field.

-Psychobabble

The reason there are no arguments for or against seems to me to be based on the fact that there is no clear definition of the boundary between microevolution and macroevolution. The definition cited in the article is based on the word "species", a word which in itself has become increasingly clear to be an artifical concept induced by man which does not model nature. Modern systematic genetics have given us a wide variety of examples of populations of animals to which no species boundaries can be drawn, or where such boundaries clearly contradict the separation of micro and macroevolution. boxed

[edit] Testable

History is testable; It's done all the time in court. The relationship between species is also testable; if species are related in particular manners, then we expect certain patterns to exist in their DNA, in their physiology, and in the fossil record. The relationships of species and structures is constantly tested in evolution studies that look for evidence of homology vs. convergent evolution.

Living (and fossilized) organisms show a lot of patterns that match up with the hypotheses that they share common ancestors. Many of these patterns were predicted beforehand, based on these hypotheses. There may be a better explanation for these patterns, but it hasn't been proposed yet.

I suggest reading this booklet from the NAS [1]. It's called "Teaching evolution and the nature of science" AdamRetchless 14:27, 18 Apr 2005 (UTC)

i agree that this is a viewpoint held by many who ascribe to evolution. however, the viewpoint held by creationists is that it is not. the sentence in question is attributed to that source. if you'd like to add a counter to the "history is not testable" argument, feel free, but the argument is attributed, widely made, and so should be left intact. Ungtss 14:29, 18 Apr 2005 (UTC)
Umm...this is not a matter of point of view, this is a matter of factural accuracy. Macroevolution is testable, is regularly tested. Hypotheses are proposed, tested, and accepted or rejected. This is not a question of whether or not one agrees with (macro)evolution - documenting the existence of skepticism is within the scope. But stating that macroevolution is untestable is denying that a wealth of scholarship exists. Guettarda 14:40, 18 Apr 2005 (UTC)
i'm afraid that even given all this, the creationists still assert otherwise, in great detail. please, sir, i don't want to debate you. the assertion is noted, attributed and then summarily dispatched by the NAS. this is what npov is made of. is this not acceptable? Ungtss 14:43, 18 Apr 2005 (UTC)
Factually incorrect points of view may and must be attributed to their proponents, and then dispatched by others. you are violating this rule in the name of your ideology, and the confusion of fact and interpretation of fact. however, six months of experience have taught me that there is a tacit "don't enforce npov" rule at wikipedia on any topic related to creationism. you are directly violating wikipedia policy. carry on. Ungtss 14:52, 18 Apr 2005 (UTC)

Are you saying that a "rebuttal" that doesn't rebut should be given? I don't understand. It's like saying "X says that the sky is blue. However, Y rebuts this by saying that the sea is orange." The factual accuracy isn't the issue here - what I have a problem with is that the rebuttal does not rebut. How is that ideology, pray tell? Guettarda 15:06, 18 Apr 2005 (UTC)

if your complaint is with the quality of the rebuttal, then feel free to fix the rebuttal. my complaint is with your deletion of an attributed, widely held, and relevent point of view. it is that deletion that smacks of ideology. the factually accurate and attributed refutation of that point of view would smack of npov. Ungtss 15:10, 18 Apr 2005 (UTC)
It was not a deletion - it was the removal of a factually inaccurate insertion. I would not have deleted something from the article that was there before without discussion. However, an anon (who has not bothered to enter this discussion) made the assertion. If it could be sourced (to say "creation scientists" is not a sourced assertion per se) I might look at it differently, although I owuld still take issue with wording. As it stand (or stood) the assertion says that CS's say that history is untestable, and thus macroevolution is a pseudoscience. That statement implies (i) that macroevol depends on history, and (ii), if history is untestable, then macroevol is untestable, and therefore pseudoscience. One of the many sources for macroevol is the historical record. But to test hypotheses using historical data is not to test history as such. In addition, there is a lot more than history - there are experimental studies. The statement is factually inaccurate, but that is the least of my concerns with it. It's unattributed - no source is provided. Can you attribute it to any one person who calls himself/herself a "creation scientist"? But more importantly, it is logically flawed - whether macroevolution is a pseudoscience or not does not depend on the falisifiability of history. In summary:
  • it is not attributed;
  • no evidence is given for how widely it is held;
  • it is not relevent, since it does not rebut anything because it does not address tha issue at hand

Guettarda 15:36, 18 Apr 2005 (UTC)

You're asking for more detail on a topic you manifestly want excluded from the page. i had hoped to keep the text short to minimize impact on the page. would you support the introduce a cited, sourced, attributed, and more detailed discussion on the topic?
Irony of this just hit me - creation scientist as empiricist? Hmmm... Guettarda 16:15, 18 Apr 2005 (UTC)
There's nothing more empirical than creationism, sir. we know what we know, and we know what we don't know. evolutionists, on the other hand, explain nothing by virtue of explaining everything. Ungtss 20:48, 18 Apr 2005 (UTC)

From Empiricism: Empiricism (greek εμπειρισμός, from empirical, latin experientia - the experience) is generally regarded as being at the heart of the modern scientific method, that our theories should be based on our observations of the world rather than on intuition or faith. Guettarda 21:07, 18 Apr 2005 (UTC)

Yep. And to my mind, belief in abiogenesis and universal common ancestry require a lot more faith than creationism. Ungtss 21:11, 18 Apr 2005 (UTC)

I disagree on content. I don't see ID as disputing macroevolution (merely the drivers thereof) while panspermia merely disputes abiogenisis on earth, it does not dispute macroevolution (speciation). As I understand it, even baraminology only disputes the degree to which macroevolution occurs. Only YECs seriously dispute macroevolution. Guettarda 21:18, 18 Apr 2005 (UTC)

panspermists, old earth creationists, intelligent design. Ungtss 21:27, 18 Apr 2005 (UTC)
  • The ID link says that "[w]hat intelligent design does reject that the notion that mutation and natural selection (combined with any other natural mechanism) is sufficient to produce or explain all aspects of life - this has nothing to do with whether ID accepts or does not accept macroevolution.
    • the second full sentence on the page, in the "short anser:" "Most intelligent design proponents accept microevolution but question if macroevolutionary changes are possible."
  • Panspermia link - does not deal with panspermia. Please see panspermia.
    • you need to read further down. particularly, the section "Does Microevolution Explain Macroevolution?"
  • OEC - you provided one link. Nonetheless, the created kinds article, together with other material I have read on baraminology allows for macroevolution. They can always define macroevolution out of their scope of acceptance, but that does not mean that they reject speciation. You have to reject speciation to reject macroevolution. ID and panspermia do not reject macroevolution. Guettarda 21:45, 18 Apr 2005 (UTC)
    • you've redefined macroevolution as requiring speciation. there is no such requirement. virtually all panspermists, yec's, and ider's acknowledge speciation, but not macro. Ungtss 21:51, 18 Apr 2005 (UTC)

I am not defining macroevolution as "requiring speciation" - macroevolution is (by definition) speciation or above. Microevolution is anything that takes place within species. Macroevolutiion is everything else - starting with speciation. Reject macroevolution, you reject speciation. Do not reject speciation and you do not reject macroevolution. Simple distinction, and utterly crucial. Guettarda 21:59, 18 Apr 2005 (UTC)

I have never seen that definition before. i don't even see it on this page. I see: "Macroevolution is the concept that evolution of species and higher taxa is the result of large-scale changes in gene-frequencies over time." i could therefore accept evolution to the level of species, but reject it at the level of genus or phylum. that is, in fact, what the above groups do. Ungtss 22:05, 18 Apr 2005 (UTC)
But this is arguing that speciation is not sufficient for macroevolution (as thusly defined), not that it's not necessary. I think there's some confusion on terms and/or direction of implication, here... BTW, some of said groups seem also to be happy with "genusification", "familyisation", and even "orderisement" in some cases, on the basis of discussions elsewhere. (To neologise in the style of a certain UK Dubya parody.) Alai 22:52, 18 Apr 2005 (UTC)
Excellent analysis, Alai. i agree. since speciation is a necessary but not sufficient condition for macroevolution, one can reject macroevolution without rejecting speciation. Ungtss 22:57, 18 Apr 2005 (UTC)

[edit] Criticism of Criticism of Criticism...

Maybe we should add a few more sections of criticisms! It would be better if someone restructured the section on Criticism to get rid of the apparent desire to fight on the issue rather than describe it. --ChadThomson 14:07, 24 November 2005 (UTC)

[edit] Rejecting macroevolution

How could you reject evolution at the genus level but not at the species level, pray tell? Genus/species borders are subjective - to do that would be to put your faith in systematists. Anyway, speciation is both sufficient (inasmuch as speciation=macroevolution) and necessary (since you cannot have stable divergence without some sort of reproductive barrier). I think you are shifting the goal posts to support your own view of things. You are re-defining macroevolution as those aspects of evolution with which I disagree. Speciation is both sufficient for macroevolution, and necessary. Anything other than evolution within a species is macroevolution. Or have you just invented mesoevolution? Guettarda 13:15, 19 Apr 2005 (UTC)

<How could you reject evolution at the genus level but not at the species level>>
From the creation biology paradigm, speciation occurs through the loss of capacity to interbreed, and the loss of genetic characteristics through genetic drift. it is a negative view of speciation -- certainly not your macroevolutionary paradigm. Ungtss 13:30, 19 Apr 2005 (UTC)
This argument could all be avoided if you would merely clarify the basis for creationist rejection of macroevolution. That would determine both why, and what the indicated meaning of macroevolution is. Graft 14:31, 19 Apr 2005 (UTC)
You're right. thanks for defining the issue. i tried to rewrite with your suggestion in mind. how did i do? Ungtss 14:49, 19 Apr 2005 (UTC)
Um. Lost me, that's for sure. Irreducible complexity is not necessarily an attack on macroevolution per se, and macroevolution need not involve violating irreducible complexity. Graft 16:02, 19 Apr 2005 (UTC)
all true. but both specified + irreducible complexity are used to argue against macroevolution. irreducible, for instance, in the case of the enzymes involved in human blood clotting. specified in the case of the increased genetic information required to get us from proto-weasel to human. i'm having a hard time figuring out what you're looking for. any suggestions on making it clearer? Ungtss 16:05, 19 Apr 2005 (UTC)
Human blood-clotting is an example of macroevolution? And I was under the impression that specified complexity is predicated on irreducible complexity. Graft 16:13, 19 Apr 2005 (UTC)
No sir. human blood-clotting is an asserted instance of irreducible complexity[2], and specified complexity is often used in conjunction with irreducible complexity, but it's a different concept. specified complexity is about information theory. irreducible complexity is about functionality. Ungtss 16:28, 19 Apr 2005 (UTC)
Blood clotting would almost certainly be microevolution - it would probably have developed within a single species. At what point do we see a split between clotters and bleeders (and I'm not talking about haemophilia)? Within species = microevolution. Guettarda 16:19, 19 Apr 2005 (UTC)
Also, I don't understand how specified complexity and irreducible complexity can be used against macroevolution - doesn't Behe say he has no problem with macroevolution per se? Guettarda 16:21, 19 Apr 2005 (UTC)
He has no problem with certain aspects of macroevolution, but he draws limits. perhaps that's the best way to articulate the objection: it's not an objection to "macroevolution" per se, but an assertion that there are limits to it. what do you think? Ungtss 16:28, 19 Apr 2005 (UTC)
You need to be more explicit. What are the limits, and why? Also, blood clotting has surely undergone a progressive development over the course of the evolutionary history of blood. Since it's multifactor and varies amongst vertebrates, it seems probable that it was built on incremental improvements over time. Some modifications to the clotting process must have happened within a species, but "clotting" as a whole must have developed across many hundreds of millions of years of evolution. Whether this makes it "macroevolution" or "microevolution", i'm not sure. Graft 17:10, 19 Apr 2005 (UTC)
I'll do that. thanks. and the argument from irreducible complexity is that blood clotting cannot have undergone such variation, because any variation would cause they entire system to fail. Ungtss 17:20, 19 Apr 2005 (UTC)

[edit] Quick policy tip

Once you've started discussing on talk, you don't need to revert again. The only reason you reverted in the first place was because the person in question hadn't explained anything yet. Your changes are still in history, you can always revert later. Just talk with people and take your time, people will see the discussion if they're really interested in the topic anyway. Once the discussion is finished you can always revert or edit as nescesary. This also saves you getting into trouble with the 3 revert rule. See also WP:HEC.

Kim Bruning 15:56, 18 Apr 2005 (UTC)

[edit] Distinction Between Microevolution and Macroevolution

No-one seems willing to attempt to describe this distinction, so I'll have a go:

Microevolution describes changes within a species, such as variations in finch beak lengths (as observed by Charles Darwin on his trip on the Beagle). Such changes may be explained in terms of variations within a population of organisms of the one species, which over time may cause a survival advantage to certain individuals, and not to others. The result, of course, is that some individuals die out, and others (with the advantageous variation) go on to survive and reproduce. Over time such variations can be 'selected' by natural processes of predation and general survival (natural selection), resulting in a 'new' strain or variant of the species, all having a particular characteristic. The crucial point to be noted is that this is a result of the filtering of the available gene pool for that species, resulting in fewer variations in the population. Given long enough (and it doesn't need to be more than a few generations), there may be no organisms other than the 'new' variant. This is exactly what is done by human animal and plant breeders, who deliberately select individuals with certain desirable characteristics, and allow only those individuals to mate or reproduce. Of course, this is not true evolution, since it does not take place via inguided natural forces, but requires human intervention.

Macroevolution, by comparison, is the emergence of new species, over presumably a very long period of time, caused at the genetic level by the introduction of new genetic material, or new information in the DNA of the organism. In other words, what might be called 'true evolution', or macroevolution, requires that natural, unguided forces cause new information to be added to existing DNA, resulting in viable changes in an individual organism, giving that organism a survival advantage over others of that species, and that that individual then goes on to reproduce, thus passing the new DNA onto the next generation. Plainly just one new organism is unlikely to result in a new species, and so the parent organism with the new DNA would have to reproduce several times in order for a viable next, 'improved' generation to emerge.

Arguments that macroevolution has been observed, and is therefore a proven event, are IMHO disingenuous. They are based on evidence that various species exist, which are hypothesised to have come from other, simpler, common ancestors. The evidence of this variation is taken to 'prove', then, that macroevolution must have taken place, plainly a circular argument. --User:Hiflyer 10:01, 4 October 2005 (UTC)

I've added the pov-boiler. This article doesn't begin to mention that macroevolution is a term created by creationists. There are other points as well. -- Ec5618 10:48, 4 October 2005 (UTC)
  1. To Ec - Are you sure macroevolution is a creationist term? That would need to be sourced. I suspect it isn't.
  2. To Hiflyer - I think you have some major misconceptions about evolution. Most simply, speciation and incipient speciation have been observed and a lot of speciation mechanisms are quite well understood; there is nothing more "real" about speciation than there is about evolution within species; natural selection is an incredibly strong "guiding force". Your last paragraph is simply wrong. Guettarda 12:57, 4 October 2005 (UTC)
Thanks for the boiler (I'm new to Wikipedia and hadn't heard of it before). I agree on re-reading that my additions to the article were not really NPOV. I still believe that a clear distinction can be made between the two terms, so I have removed some biased language, and left the main 'Criticim' section. I hope others will agree that it adds usefully to the page.
Guettarda: I do not accept that speciation is as clearly evidenced as change within species; the difference in changes required in DNA surely show that there is a fundamental distinction between them, to the extent that one of the terms could really do with changing, since they sound so similar.--Hiflyer 21:01, 4 October 2005 (UTC)
Speciation can occur with only limited genetic change - for example, through polyploidy (as in the evolution of wheat), or through alteration of mating behaviour (once these are genetically rooted) - for example, there are bird "populations" which differ in mating calls, and which do not recognise the mating calls of other populations currently classified within the same species - technically, these are different species (since they have achieved pre-zygotci isolation), but, at present, there is no way to distinguish them morphologically. Speciation can be a trivial even, but it frees species to diverge evolutionarily. That's really the whole difference between mico- and macro Guettarda 21:35, 4 October 2005 (UTC)
Agreed. If you accept the basic premise of functional genetic variation, which I think nearly everyone does, then speciation is an almost direct implication. Consider an obvious mechanism of speciation, which is gonadal incompatibility (i.e., the male and female organs are physically unable to interface in order to complete insemination). Dobzhansky described a simple ratcheting mechanism that can result in speciation (genotypically, but which can be illustrated phenotypically as follows). It ought to be obvious that genetic variation can exist in this regard, and in an isolated population genetic drift will eventually result in the population subtly changing over time - normal, interspecific variation. Meanwhile, consider a separate population that, by mere chance, drifts in a different direction. Size is probably easy to imagine. Now, when these two sub-populations encounter one another, they are unable to interbreed. Speciation has occurred, and subsequently the general drift of evolution will take them further and further apart. Graft 21:50, 4 October 2005 (UTC)
But if speciation includes examples such as this, then a distinction is still needed between the sort of "filtered DNA pool" type change, and the "added information in DNA" type - the differences go in opposite directions, and so cannot be considered as the same thing. I expect we can all imagine geographically-separated populations of birds of one species which develop over time incompatible mating calls. Is this really a new species - has the DNA changed through the addition of new information? This seems unlikely. Sure, this is "trivial speciation", but as for "[freeing] species to diverge evolutionarily"? The statement again assumes that micro- and macroevolution are different only in degree, but does not demonstrate evidence to support this conjecture. --Hiflyer 09:22, 7 October 2005 (UTC)
I don't understand what you mean by "filtered DNA pool" type change, and the "added information in DNA" type. But with regards to the second parts of your question, if the mating calls are genetically programmed (which is the case in most bird species), then yes, of course, the DNA must have changed. Of course this is speciation, as species are usually defined. See species (and I'm serious, there's a discussion there about what "species" means. As for "The statement again assumes that micro- and macroevolution are different only in degree" - yes, of course it does. They are the same. It's just a matter of terminology. I can't picture how you would make the distinction. Say, species A splits into two groups, A1 and A2. They meet back up, and they can no longer interbreed - so they are species. So differences between them could be studied as "macroevolution" (since it involved change between what are now two species) but differences between any two ancestral populations in the A1 lineage (and in the A2 lineage) and their ancestors would only be micrevolutionary. The difference between the two is more semantic than anything else. Guettarda 13:09, 7 October 2005 (UTC)

[edit] the first line and definitions

Macroevolution is the concept that evolution of species and higher taxa is the result of large-scale changes in gene-frequencies over time.

Can we shoot for something a little more accessible to the common reader? gene-frequencies is not a well known concept...heck...I'll admit I don't even know what it means. The ID debate in the US has been big news the past few months and more than a few curious soulds might make their way here trying to figure out what all the terms mean.

There also seem to be two definitions in the air:

- The first is that macroevolution occurs when "new species" appear. Supposedly this has never been witnessed. This seems to be a definition supported by intelligent design -- I've heard it personally from ID adherents. Evolutionary scientists would probably argue that the dividing line between species is fuzzy and often only "micro"scopic. - The second has more to do with morphology -- not just new species appearing, but species that look substantially different from each other (the "higher taxa" mentioned above) due to changes in homoebox-related genes. It seems that at least some evolutionary scientists would accept this as a definition.

Is my understanding of this correct?

These dual definitions, and the multiple definitons of species (there are seven on the species page), leads to a neverending rat's nest of intelligent design vs evolution confusion. For instance "We've never seen macroevolution" or "yes we have!" could mean over ten different things. -Justforasecond 02:29, 12 December 2005 (UTC)

I haven't gone through this silly debate to see if it has been mentioned, but there is a clear difference between microevolution and macroevolution. Microevolution is reversable (gene frequencies, etc.), whereas macroevolution is not.

[edit] on the context flag

I put the context flag up because the intro is too hard for anyone to understand. In particular "large-scale changes in gene-frequencies" is tough for a newcomer. In wiki we have:

- Macroevolution is the concept that evolution of species and higher taxa is the result of large-scale changes in gene-frequencies over time.

Compare to google "define", where some of the definitions are much simpler [3]:

  1. Large scale change in organisms resulting in new species, genera, families, etc.
  2. Evolution on the grand scale resulting in the origin of higher taxa. In evolutionary theory it thus entails common ancestry, descent with modification, the genealogical relatedness of all life, transformation of species, large scale functional and structural changes, etc.
  3. Larger changes in evolution, such as when a new species is formed or a mass extinction.
  4. The study of evolutionary changes that take place over a very large time-scale. Contrast to microevolution. Macroevolutionary change is usually recognised as change in gross morphology in a series of fossils. There is some controversy over whether macroevolutionary change is fundamentally just cumulated microevolutionary change, or whether the two are `decoupled' and driven by fundamentally different kinds of process.
  5. The branching of new species from existing species.

The other thing about these definitions is that its odd that the wiki definition is different than all of these. It should express at least most of what the internet says.

-Justforasecond 02:58, 29 December 2005 (UTC)

Regarding Cyde's edit - I disagree with the "over a long period of time" - speciation can occur over a short period of time. I don't think we should have an unsourced summary of what macroevolution is.
Regarding JFAS's comments - google is not a good place to define scientific concepts. The existing defintion was pretty accurate, if not as "accessible" as some might like. Guettarda 03:36, 29 December 2005 (UTC)
The current intro is unsourced and out of line with the numerous definitions online. -Justforasecond 03:45, 29 December 2005 (UTC)
It agrees with (1) and (5); (2) is a general statement on evolution; (3) is incomplete (and thus, inaccurate), (4) is inaccurate. Guettarda 03:55, 29 December 2005 (UTC)
I think maybe we should lengthen the intro to more than one sentence. I agree that it is confusingly worded as it is now. I know a lot about the subject and I can only puzzle out the meaning because I know what the meaning should be and because I know what every other word in the sentence means. I just don't have a good verbalization of the meaning. Gahhhrr. --Cyde Weys votetalk 03:48, 29 December 2005 (UTC)
I've merged the one-sentance intro with the "overview", since the intro is supposed to be an overview of the topic. It still needs work, of course. Guettarda 03:55, 29 December 2005 (UTC)
Looks a lot better guys. It could be impoved...but so can everything else. I'm removing the flag -Justforasecond 16:03, 29 December 2005 (UTC)

[edit] Macroevolution and transitional forms

The lack of transitional forms in the fossil record leads many to question macroevolution. I think this would be a helpful addition to the topic. Picture animals evolving from having exoskeletons to endoskeletons. Picture animals evolving from having open cirulatory systems to closed ones. Picture the process of animals with no limbs, evolving fins, and then other functioning appendages. Why do scientists get excited when they find one supposed transitional form? Given the number of species on the earth today, there would necessarily be thousands and thousands of transitional forms that would reflect macroevolutionary change. The only clear evidence in the fossil record is that of the Cambrian explosion, which disproves Darwin's phylogeny. I also agree that mutations and natural selection are insufficient to produce macroevolutionary change, given the assumption that such changes are gradual. Scientists that recognize this insufficiency and the lack of transitional forms are forced to create new theories that support their naturalistic bias. I don't understand why reputable scientists more readily accept something like the punctuated equilibrium theory rather than admit the logic and scientific evidence of irriducible complexity and the Cambrian explosion. LAInquiry

What lack of transitional forms? The fossil record is full of them. Guettarda 02:04, 2 January 2006 (UTC)
I may be misreading your post, LAInquiry. Are you suggesting that, while the idea of a closed circulatory system evolving from an open circulatory system may seem incredible, it isn't really. Are you suggesting that we should make the context of such examples, the 'Eureka'-ness if you will, more clear in the article?
Or are you suggesting that since you do not find the idea of such evolution plausible, we should add to the article that it is in fact highly improbable?
For the record, the fossil record is indeed quite large, and shows many creatures that seem to be evolutionary ancestors of other creatures. Creatures with rudimentary feathers, for example, used them to keep warm. And to suggest that the incompleteness of the fossil record is any way indicative of problems with evolution is naive, as it suggests that there should be fossilised remains of every creature that ever walked the Earth. What is amazing, is that no fossils have ever been inconsistent with evolutionary theory. -- Ec5618 02:26, 2 January 2006 (UTC)
Thanks for the thoughtful reply, Ec5618. I want to respond to your last comment, that "no fossils have ever been inconsistent with evolutionary theory." Is it even hypothetically possible to produce a fossil that could disprove the evolutionary theory, given that the lack of fossils is the problem? Also, my questions go beyond an intuitive sense of the implausibility of macroevolution, though they definitely include that. I don't believe that the fossil record is merely "incomplete," but rather sorely lacking in necessary evidence of the gradualism of macroevolution. Steven J. Gould agrees:
“The history of most fossil species include two features particularly inconsistent with gradualism:
1) Stasis - most species exhibit no directional change during their tenure on earth. They appear in the fossil record looking much the same as when they disappear; morphological change is usually limited and directionless;
2) Sudden appearance - in any local area, a species does not arise gradually by the steady transformation of its ancestors; it appears all at once and 'fully formed'.”
"Evolution's Erratic Pace." Natural History, vol. 86, May 1977
Michael Denton continues this idea while alluding to the Cambrian explosion:
"It is still, as it was in Darwin's day, overwhelmingly true that the first representatives of all the major classes of organisms known to biology are already highly characteristic of their class when they make their initial appearance in the fossil record. This phenomenon is particularly obvious in the case of the invertebrate fossil record. At its first appearance in the ancient paleozoic seas, invertebrate life was already divided into practically all the major groups with which we are familiar today."
Evolution: A Theory in Crisis (1986)
I am new to Wikipedia so I don't know if there is a place for these sorts of quotes on the evolution page, or whether they fit better under Macroevolution, or if they are not "factual" enough to be included. I noticed under the Intelligent Design page (among others) there was more of a discussion of the nature of the controversy than there was a presentation of facts supporting the issue. So I am a little confused as to what is considered fair game for posting.LAInquiry 08:43, 4 January 2006 (UTC)
This isn't the place to debate whether evolution or some other theory is best (though it might be fun to do it on the talk page ;). Get some notable sources about MACROEVOLUTION, gather information from them, insert it into the article and cite it. I found it to be pretty messy territory. Just for starters...try defining "species" in a way that works for fossils, dogs, bacteria, and ligers -Justforasecond 07:59, 2 January 2006 (UTC)
For the record, yes, theoretically a fossil could disprove evolution. But the odds of that happening are now rediculously small, not because the odds of finding that one fossil are small, but because virtually all fossils should then disprove evolution.
If evolution didn't happen, we should have found glaring inconsistencies in the fossil record; cows next to dinosaurs, 40 metres tall ferns next to house cats. We haven't. We have found thousands of fossils, all of which fit with established theory. And we keep finding new fossils, which all fit with established theory.
On top of which, every scientist knows that if ve could disprove evolution, ve would be remembered for generations, and would be rich beyond belief. If is, in a way, the holy grail of science: everyone is looking for it, yet no-one has found it. Let that be enough. -- Ec5618 01:52, 6 January 2006 (UTC)

[edit] Dichotomy

The article is currently worded to suggest that either evolution is a slow process, or it moves in spurts. Shouldn't we make it clear that even if some evolutionary processes may move quickly, the overall process is/may still be/ gradual? I can imagine insects growing in length quite quickly, as individual body segments are added, but that doesn't mean all of evolution must be a quick and erratic road to nowhere. -- Ec5618 01:29, 6 January 2006 (UTC)

The gradualism vs. punctuated equilibrium debate you bring up here belongs elsewhere - perhaps on those pages. This debate, however, is a topic within the scope of the study of macroevolution. There is a real debate between these viewpoints - even though some lineages and characters may evolve either way - because of a history. Eldridge and Gould in a sense set up a straw man of gradualism to be knocked down by punc eq... but this my opinion.

What should be discussed more clearly in this article (as has been discussed with intermittent clarity on this talk page) is the real debate about whether there are truly different processes occuring at the macro (above species) and micro (within species) levels. Just because the species concept is problematic doesn't mean that we can't talk about speciation and processes that may occur on deeper evolutionary timescales. Safay 07:53, 25 January 2006 (UTC)

[edit] Intro still needs rewriting

Check this out:


The term macroevolution refers to the emergence of new species and higher taxa through evolution, which, according to some cannot be explained using the gradual changes inherent in evolution. It is often used in the creation evolution controversy to refer to the part of evolution that cannot be directly observed, and contradicts scripture. The term 'species' has atleast six conflicting definitions making speciation difficult to define.
Most evolutionary biologists, among whom Charles Darwin and those subscribing to the modern synthesis, see the only difference between microevolution and macroevolution as being one of scale. Other evolutionary biologists, including Gould , Schmalhausen, and Waddington, hold that microevolution and macroevolution are fundamentally different processes. They essentially hold that sudden developmental 'spurts' are more important to the overall process of evolution than small incremental changes are.


Ignoring the mispellings, here are some problems I see with it.

  1. From the first sentence, "gradual changes inherent in evolution" is clumsy and perhaps factually incorrect. And the "according to some" needs to be more specific ... only evolution deniers would say that small changes cannot add up into larger changes.
  2. Macroevolution has been observed in the laboratory (See TalkOrigins), so saying it "cannot be directly observed" is simply false.
  3. "Contradicting scripture" here is irrelevant, but even if a decision is made that it must stay, this needs to be a lot more clear exactly what it's talking about. How about at least referencing the Book of Genesis of the Bible.
  4. I don't think it's correct to characterize Gould's punctuated equilibrium as saying that micro and macro evolution are different processes. Punctuated equilibrium merely says that evolution speeds up in spurts in times of fast environmental flux. He's not talking about an actually different kind of evolution. As for Schmalhausen and Waddington, I don't know anything about them ... are they even notable?

Well that's enough beating up on the intro for now. I just wanted to bring this here so we could discuss first. --Cyde Weys votetalk 03:26, 6 January 2006 (UTC)


As current definition seems to be saying that macroevolution is closely linked to speciation, how about something along these lines: "Macroevolution is the process of speciation (the emergence of species and higher taxa) through large-scale changes in gene frequencies, in a population, over a geological time period". And make sure this article says things that aren't already covered in the Speciation article, otherwise why should it exist? PiCo 10:20, 15 January 2006 (UTC)
Most of the definitions online don't include anything about "large scale changes in gene frequencies". Also, it is tough to word, but there is a sense that macroevolution results in taxa that have distinct appearance (morphological concept of species). This has been dismissed before, but I think these definitions are a good place to start: [4] . -Justforasecond 17:36, 15 January 2006 (UTC)
If most definitions don't mention "large scale changes" etc, then you'd better tell the folks over on the Microevolution page :). 203.221.81.154 02:45, 16 January 2006 (UTC)

I'm new here, but I'll have a go.

Macroevolution refers to evolution that occurs above the level of species. In contrast, microevolution refers to smaller evolutionary changes (generally described as changes in genotype frequencies) in populations that, in the Modern Synthesis of evolutionary thought, are the "normal" mode of evolution. Thus the process of speciation is the link between macroevolution and microevolution, and it falls within the perspective of either. Paleontology and evo-devo contribute most of the evidence for the patterns and processes that can be classified as macroevolution.
Some examples of subjects whose study falls within the realm of macroevolution:
Macroevolution is controversial in two ways:
  • It is disputed among biologists whether there are macroevolutionary processes at all. Some will assert that there are no evolutionary processes that are not described by classical population genetics. This view is becoming less tenable as the role for genome-wide changes and developmental processes in evolution become clearer.
  • The concept of macroevolution has been coopted by creationists. They use its controversy in evolutionary theory as a supposed "hole" in the evidence for deep-time evolution.

I have to admit I don't know too much about the creationist use of this term, but I don't think there needs to be much mentioned about creationism in this article, except maybe a bit more about how they have coopted it for their purposes. However, surely it's a hotbutton issue and I'd hate to get embroiled in a debate here on wikipedia over it.

Please have a look at this and make suggestions on how to improve it. With a bit more time I think I can find the proper references, i.e., first use of the term, etc. I am mostly concerned about using too much jargon - I'm a biologist and this is a subject I have studied, so my perspective is tainted. Is this clear?

You know what, I just had another look at the page itself, and am going to be bold and change the intro to this. Sorry if I am being presumptive... And please edit my awful prose.

Safay 08:58, 25 January 2006 (UTC)

[edit] The 'Cambrian Explosion' exploded.

Regarding the 'Cambrian explosion'. The entire basis for this interpretation of the fossil evidence (that new phyla of metazoan animals all developed over a short time period of 30-40 million years) has been shown to be seriously flawed by the discovery of new Precambrian fossils in Australia:

http://www.pandasthumb.org/archives/2006/01/steve_steve_sli.html

[edit] History of Macroevolution

Most of the material currently in this section can be found on the history of evolutionary thought page. I feel that it instead needs to be honed in on the key points of macroevolutionary thought vs. modern synthesis thought.

"Today, the synthetic model of evolution and punctuated equilibrium are alternative models for the theory of evolution."

Please note that macroevolutionary thought is not exclusive of population genetics. It only says that there are processes that occur above the level of genotype frequency change and "normal" speciation. It adds on top of the Modern Synthesis, it doesn't supplant it.

This erroneous view that macroevolutionary theory is in opposition to the Modern Synthesis is precicely the thing that the creationists have latched onto. No evolutionary biologist would ever assert that Modern Synthesis processes like genotype frequency change and allopatric speciation are unimportant in evolution - some would just like to assert that there are additionally other processes occuring at higher levels. The problem with the Modern Synthesis is that it was not truly whole synthesis - yes, it reconciled evidence from population genetics and Darwin (which is why it is also called "neo-Darwinian") but it left out evidence from developmental biology and paleontology that could not be explained through simple genotype frequency changes.

Sorry for the rant. This page needs a lot of work. I have to take a look at the Microevolution page before attempting any other changes - a wholesale reworking is in order.

Safay 19:22, 25 January 2006 (UTC)

Hello, I'm RKM (Norway), I'm new to this, but I take the chance of making an absolute fool of myself. The term "macroevolution" is unsatisfactory, because it means too much, and too little. When non-darwinists talk about "macroevolution", they mean much more than just the appearance of new species. They mean the appearance of whole new classes, and this should be called megaevolution. I believe the whole editing talk about macroevolution will become a lot easier if you introduce the word megaevolution. The word macroevolution will then loose a lot of the significance and the ambiguity that it has today. Thanks!

Wikipedia is not in the business of defining words, I'm afraid. The goal is to catalogue knowledge, not shape it. -- Ec5618 10:55, 1 February 2006 (UTC)
The term is unsatisfactory, but the fact is, it exists and it is used. Defining words is sometimes unavoidable in order to discuss or describe concepts and ideas, as Wikipedia tries to do. I don't have time to work on this article but there are a couple of important things that should be noted. First, the term "macroevolution" is defined very differently by evolutionary biologists and by creationists; this leads to endless confusion and the two groups tend to talk past each other because of this. Second, the term "macroevolution" as used by biologists has changed over time; in the older sense it meant something closer to how creationists now use the term, i.e., changes from one major group to another, such as the evolution of tetrapods from fish, or birds from dinosaurs, whereas biologists now use it to mean virtually any evolution above the level of species, including speciation itself. The flip side of this is that evolutionary biologists generally use "microevolution" to refer to changes occurring within species, whereas creationists regard as "microevolution" the evolutionary radiation of species within an entire genus (e.g., Equus). The differing usages of such terms must be noted for the articles to make any sense. MrDarwin 14:01, 6 February 2006 (UTC)


Thanks MrDarwin. I tried to outline this by indicating that there are two seperate controversies, the one between the Modern Synthesis folks and evo-devo/paleo folks (i.e., whether there exist processes above the level of species that drive evolution), and the creationists vs. evolutionists, but it can be much clearer. You outline a third distinction that recognizes the historical change of the term (that is, it emerged from the paleo people and has now reached a broader focus in the context of the levels of selection debate) that should be included in the history section. It's interesting to see the various contributors' points of view get fed into this page as it develops. This is the first time I've been involved in a (albeit mildly) controversial page in its earlier stages of "evolution." Frustrating but fascinating on its own level. Clearly this topic requires research beyond online resources or just a single printed reference. My next task is to try to put together a reference list. Thanks again.
Safay 19:20, 9 February 2006 (UTC)

[edit] Merging

One is a fact and one is a theory, why merge them? They're two related but seperate ideas. It'd be like if we merged the pages for England and Scotland. --Scorpios 18:46, 12 February 2006 (UTC)

Scorpios, I am glad you have started a thread on this.
I don't quite follow your analogy between England and Scotland and this issue of macro- and microevolution merger. England and Scotland exist quite well each as their own entity; the existence of one as a geographic object does not depend on the other. The idea of "microevolution" does not exist on its own, it only exists in contrast to the idea that there are macroevolutionary patterns and processes. See adam's comments above.
Can you show how the understanding of one is not contingent upon the other?
As another point, you bring up that one is a "fact" and the other a "theory." I would argue that both are facts and theories. The patterns we observe are "facts," if you want to use the word "fact" at all; most scientists would prefer to just call them observations. We observe both macro- and microevolutionary patterns. The scientific explanations for the processes underlying these patterns are all based on theory. This is how science works; there is no getting around that. With both macro- and microevolutionary thought, the explanations are theory. That theory is tested with both historical and experimental evidence. There are some evolutionary biologists who would assert that we need invoke no more than microevolutionary processes to explain the evolution of life; there are others who would invoke macroevolutionary processes. This is a debate independent of any creationist/evolutionist debate.
Safay 00:43, 13 February 2006 (UTC)
Should we merge good and evil while we're at it ;) Justforasecond 03:35, 31 March 2006 (UTC)

[edit] Creationism

Cut:

  • A misunderstanding about this biological controversy has allowed the concept of macroevolution to be coopted by creationists. They use this controversy as a supposed "hole" in the evidence for deep-time evolution.

The article does not clarify what "misunderstanding" this might be. In fact, the article is so vague in its use of the technical term "allele frequencies" that the distinction between microevolution and macroevolution is lost. Or is that the point?

Are their writers (scientists, I hope) who assert that macroevolution is in no way different from microevolution?

Anyway, how has the concept been "coopted"? And who asserts that there is no hole in the evidence (or that there is a hole)?

Should this discussion be linked to Evidence for evolution? --Uncle Ed 19:59, 23 August 2006 (UTC)

[edit] Criticisms of macroevolution

I read through this and counted the number of "scholarly" (non-religous) criticisms, then I read through again to tally up the number of reliable sources provided for the criticisms. At no point in this process was I required to remove my shoes to perform advanced calculations on my toes. In both cases, the number is zero. Frankly, I think it is simply absurd to include religous criticisms on a scientific topic. Compared to the number of "qualified" opinions on the subject, Creationists are a miniscule minority, and to mention them at all, even briefly, is to give them undue weight. It simply isn't relevant here. I'm going to cut this back severely, and we might consider removing it entirely. If anyone objects to my action, I'm more than willing to discuss it here. Doc Tropics 18:37, 1 December 2006 (UTC)

Strike it down, boyo. Adam Cuerden talk 18:39, 1 December 2006 (UTC)
Done. I really don't think it merits any more detail than it has now; the so-called criticisms are nonsense and there is no need to accord them further mention.

[edit] modern synthesis -- 2x

the modern synthesis is cited as being coined in the 30s and the 60s....which is it?

Amarilloarmadillo 07:41, 4 December 2006 (UTC)


Hi Armadillo, the way you organized the sections looks good, but I'm curious why you removed half of Gould's quote. Was that perhaps accidental? Doc Tropics 07:47, 4 December 2006 (UTC)

[edit] Macroevolution Impossible?

There are many points of macroevolution which could be called an "unconfirmed hypothesis". Why not include how it is unknown whether a species can microevolve to a point where the number of alleles changes. I am new at wikipedia but I don't understand why such a large and controversial topic remains a medium sized article. Aidepolcycne eerf 04:21, 11 January 2007 (UTC)

Can you explain what you mean? Macroevolution is scientifically uncontroversial. Guettarda 04:58, 11 January 2007 (UTC)

[edit] NPOV template

This article focusses heavily on the "contraversy" of the subject matter without any focus on other relevant areas. Specifically the science of the term macroeveolution, and the history of its usage. The tone(e.g. word choices such as "evolutionist") of the article seem to be originated from creationist attacks on the theory of evolution rather than proper scientific terminology. As a counter-example, compare this article to the one on Microevolution. i kan reed 22:58, 26 March 2007 (UTC)

What word do you think should be substituted for 'evolutionist'? And should the term 'creationist' not be used also? 69.211.150.60 12:55, 27 March 2007 (UTC)
Well it does depend on the context. Scientists have particular titles. Evolutionary biologist for those who study evolution in life. Particular focuses have different names. i kan reed 15:55, 27 March 2007 (UTC)
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