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? view · edit Frequently asked questions

Many of these questions are rephrased objections to evolution that users have argued should be included in the text of Evolution. The reason for their exclusion is discussed below.

The main points of this FAQ can be summarized as:

  • The process and theory of evolution are both uncontroversial among biologists.
  • Misplaced Pages:Neutral point of view requires that minority views not be given undue emphasis.
  • Therefore it is against Misplaced Pages policy for views without scientific support, such as all known objections to evolution, to be interjected into a science article like Evolution.

More detail is given on each of these points, and other common questions and objections, below.

To view the response to a question, click the link to the right of the question.

Q1: Why won't you add criticisms or objections to evolution in the Evolution article? A1: This is essentially mandated by Misplaced Pages's official neutral point of view policy. This policy requires that articles treat views on various subjects proportionally to those views' mainstream acceptance in the appropriate academic field. For example, if two contradictory views in physics are held by roughly an equal number of physicists, then Misplaced Pages should give those views "equal time". On the other hand, if one view is held by 99% of physicists and the other by 1%, then Misplaced Pages should favor the former view throughout its physics articles; the latter view should receive little, if any, coverage. To do otherwise would require, for example, that we treat belief in a Flat Earth as being equal to other viewpoints on the figure of the Earth.

Due to the enormous mainstream scientific consensus in support of modern evolutionary theory, and pursuant to Misplaced Pages's aforementioned policies, the Evolution article references evolution as an observable natural process and as the valid explanation for the diversity of life on Earth. Although there are indeed opposing views to evolution, such as Creationism, none of these views have any support in the relevant field (biology), and therefore Misplaced Pages cannot, and should not, treat these opposing views as being significant to the science of evolution. On the other hand, they may be very significant to sociological articles on the effects of evolutionary theory on religious and cultural beliefs; this is why sociological and historical articles such as Rejection of evolution by religious groups give major coverage to these opposing views, while biological articles such as Evolution do not.

Further information: Misplaced Pages:Neutral point of view § Undue weight Q2: Evolution is controversial, so why won't you teach the controversy? A2: As noted above, evolution is at best only controversial in social areas like politics and religion. The fact that evolution occurs and the ability of modern evolutionary theory to explain why it occurs are not controversial amongst biologists. Indeed, numerous respectable scientific societies, such as the American Association for the Advancement of Science and the National Academy of Sciences, have issued statements supporting evolution and denouncing creationism and/or ID. In 1987 only about 0.15% of American Earth and life scientists supported creationism.

Thus, as a consequence of Misplaced Pages's policies, it is necessary to treat evolution as mainstream scientific consensus treats it: an uncontroversial fact that has an uncontested and accurate explanation in evolutionary theory. There are no scientifically supported "alternatives" for this view.

However, while the overall theory of evolution is not controversial in that it is the only widely-accepted scientific theory for the diversity of life on Earth, certain aspects of the theory are controversial or disputed in that there actually are significant disagreements regarding them among biologists. These lesser controversies, such as over the rate of evolution, the importance of various mechanisms such as the neutral theory of molecular evolution, or the relevance of the gene-centered view of evolution, are, in fact, covered extensively in Misplaced Pages's science articles. However, most are too technical to warrant a great deal of discussion on the top-level article Evolution. They are very different from the creation–evolution controversy, however, in that they amount to scientific disputes, not religious ones.

Further information: Teach the Controversy and Level of support for evolution Q3: Why is evolution described as though it's a fact? Isn't evolution just a theory? A3: That depends on if you use the words evolution, theory, and fact in their scientific or their colloquial sense. Unfortunately, all of these words have at least two meanings. For example, evolution can either refer to an observed process (covered at evolution), or, as a shorthand for evolutionary theory, to the explanation for that process (covered at modern evolutionary synthesis). To avoid confusion between these two meanings, when the theory of evolution, rather than the process/fact of evolution, is being discussed, this will usually be noted by explicitly using the word theory.

Evolution is not a theory in the sense used on Evolution; rather, it is a fact. This is because the word evolution is used here to refer to the observed process of the genetic composition of populations changing over successive generations. Because this is simply an observation, it is considered a fact.

Fact has two different meanings: in colloquial usage, it refers to any well-supported proposition; in scientific usage, it refers to a confirmed observation. For example, in the scientific sense, "apples fall if you drop them" is a fact, but "apples fall if you drop them because of a curvature in spacetime" is a theory. Gravity can thus either refer to a fact (the observation that objects are attracted to each other) or a theory (general relativity, which is the explanation for this fact). Evolution is the same way. As a fact, evolution is an observed biological process; as a theory, it is the explanation for this process. What adds to this confusion is that the theory of evolution is also sometimes called a "fact", in the colloquial sense—that is, to emphasize how well supported it is.

When evolution is shorthand for "evolutionary theory", evolution is indeed a theory. However, phrasing this as "just a theory" is misleading. Theory has two different meanings: in colloquial usage, it refers to a conjecture or guess; in scientific usage, it refers to a well-supported explanation or model for observed phenomena. Evolution is a theory in the latter sense, not in the former. Thus, it is a theory in the same sense that gravity and plate tectonics are theories. The currently accepted theory of evolution is known as the modern evolutionary synthesis.

Further information: Evolution as fact and theory Q4: But isn't evolution unproven? A4: Once again, this depends on how one is defining the terms proof and proven. Proof has two meanings: in logic and mathematics, it refers to an argument or demonstration showing that a proposition is completely certain and logically necessary; in other uses, proof refers to the establishment and accumulation of experimental evidence to a degree at which it lends overwhelming support to a proposition. Therefore, a proven proposition in the mathematical sense is one which is formally known to be true, while a proven proposition in the more general sense is one which is widely held to be true because the evidence strongly indicates that this is so ("beyond all reasonable doubt", in legal language).

In the first sense, the whole of evolutionary theory is not proven with absolute certainty, but there are mathematical proofs in evolutionary theory. However, nothing in the natural sciences can be proven in the first sense: empirical claims such as those in science cannot ever be absolutely certain, because they always depend on a finite set of facts that have been studied relative to the unproven assumptions of things stirring in the infinite complexity of the world around us. Evolutionary science pushes the threshold of discovery into the unknown. To call evolution "unproven" in this sense is technically correct, but meaningless, because propositions like "the Earth revolves around the Sun" and even "the Earth exists" are equally unproven. Absolute proof is only possible for a priori propositions like "1 + 1 = 2" or "all bachelors are unmarried men", which do not depend on any experience or evidence, but rather on definition.

In the second sense, on the other hand, evolutionary theory is indeed "proven". This is because evolution is extremely well supported by the evidence, has made testable confirmed predictions, etc. For more information, see Evidence of evolution.

Main article: Evidence of evolution Q5: Has evolution ever been observed? A5: Evolution, as a fact, is the gradual change in forms of life over several billion years. In contrast, the field of evolutionary biology is less than 200 years old. So it is not surprising that scientists did not directly observe, for example, the gradual change over tens of millions of years of land mammals to whales. However, there are other ways to "observe" evolution in action.

Scientists have directly observed and tested small changes in forms of life in laboratories, particularly in organisms that breed rapidly, such as bacteria and fruit flies. A famous experiment was developed in 1992 that traced bacterial evolution with precision in a lab. This experiment has subsequently been used to test the accuracy and robustness of methods used in reconstructing the evolutionary history of other organisms with great success. Evolution has also been observed in the field, such as in the plant Oenothera lamarckiana which gave rise to the new species Oenothera gigas, in the Italian Wall Lizard, and in Darwin's finches.

Scientists have observed significant changes in forms of life in the fossil record. From these direct observations scientists have been able to make inferences regarding the evolutionary history of life. Such inferences are also common to all fields of science. For example, the neutron has never been observed, but all the available data supports the neutron model.

The inferences upon which evolution is based have been tested by the study of more recently discovered fossils, the science of genetics, and other methods. For example, critics once challenged the inference that land mammals evolved into whales. However, later fossil discoveries illustrated the pathway of whale evolution. So, although the entire evolutionary history of life has not been directly observed, all available data supports the fact of evolution.

Main article: Evidence of evolution Q6: Why is microevolution equated with macroevolution? A6: The article doesn't equate the two, but merely recognizes that they are largely or entirely the same process, just on different timescales. The great majority of modern evolutionary biologists consider macroevolution to simply be microevolution on a larger timescale; all fields of science accept that small ("micro") changes can accumulate to produce large ("macro") differences, given enough time. Most of the topics covered in the evolution article are basic enough to not require an appeal to the micro/macro distinction. Consequently, the two terms are not equated, but simply not dealt with much.

A more nuanced version of the claim that evolution has never been observed is to claim that microevolution has been directly observed, while macroevolution has not. However, that is not the case, as speciations, which are generally seen as the benchmark for macroevolution, have been observed in a number of instances.

Further information: Microevolution and Macroevolution Q7: What about the scientific evidence against evolution? A7: To be frank, there isn't any. Most claimed "evidence against evolution" is either a distortion of the actual facts of the matter, or an example of something that hasn't been explained yet. The former is erroneous, as it is based on incorrect claims. The latter, on the other hand, even when accurate, is irrelevant. The fact that not everything is fully understood doesn't make a certain proposition false; that is an example of the argument from ignorance logical fallacy. Examples of claimed evidence against evolution:
  1. There aren't any transitional fossils, or there aren't enough.
    There are many transitional fossils, including Archaeopteryx (earliest and most primitive bird known), Thrinaxodon (a cat-sized mammal-like "reptile"), Tiktaalik (fish with many features akin to those of four-legged animals), Acanthostega (first vertebrate animal to have recognizable limbs), and Ambulocetus (early whale that could walk as well as swim). See also List of transitional fossils. That there are not more is explained by the rarity of fossilization and by punctuated equilibrium. Furthermore, technically all fossils are transitional fossils, because no species is fixed and unchanging. For example, you can argue that Homo erectus is a transitional fossil between Homo sapiens and Homo habilis. But in the same line of thought, you can say Homo habilis is a transitional fossil between A. afarensis and Homo erectus, and so on.
  2. Evolution violates the second law of thermodynamics, "the entropy of an isolated system not in equilibrium will tend to increase over time, approaching a maximum value at equilibrium".
    Organisms are not isolated systems. Rather, they are open systems; they exchange energy with their environment, and thus their entropy can either increase or decrease. Specifically, the main fuel source for evolution is the Sun, which is continually adding energy to the Earth ecosystem. See also Entropy and life.
  3. Evolution can't create "irreducibly complex" structures like the eye, or the bacterial flagellum.
    Both the vertebrate eye and the bacterial flagellum are well understood to have evolved from simpler structures. Indeed, simpler eye-like structures (such as the sea squirt's ocellus) can still be found in existing species. Complex biological traits can also evolve as exaptations, where ancestral structures that evolved for different reasons become coopted for new functions. "Irreducible complexity" is, in any case, neither a scientific concept nor a coherent argument: A less than full understanding of the evolutionary history of a biological structure is not evidence against evolution, any more than a less than full understanding of the gravitational orbit of every astronomical body is evidence against gravity. The empirical evidence for evolution is substantial, whereas no evidence has ever been provided for irreducible complexity.
  4. Evolution can't create new information.
    New information is created every time a mutation occurs. Even random "noise" is a form of information. (This random information is then non-randomly propagated by natural selection.) Examples of the evolution of completely new information include the enzymes of nylon-eating bacteria, which can digest nylon, a polymer that didn't exist before 1935.
With regard to the Misplaced Pages Evolution article, if there is any evidence against evolution, it has yet to be accepted by any peer-reviewed scientific publication. This means that even if every editor on Misplaced Pages knew that there was evidence against evolution, we could not add that information to the article without violating Misplaced Pages's official policies of no original research and neutral point of view. Whether editors think that evolution has evidence against it or not is irrelevant; what matters are the noteworthy scientific views on this issue. Q8: How could life arise by chance? A8: If by "arise", one means "develop from non-organic matter through abiogenesis", then this is a question that is not answered by evolutionary theory. Evolution only deals with the development of pre-existing life, not with how that life first came to be. The fact that life evolves is not dependent upon the origin of life any more than the fact that objects gravitate towards other objects is dependent upon the Big Bang.

On the other hand, if by "arise" one means "evolve into the organisms alive today", then the simple answer is: it didn't. Evolution does not occur "by chance". Rather, evolution occurs through natural selection, which is a non-random process. Although mutation is random, natural selection favors mutations that have specific properties—the selection is therefore not random. Natural selection occurs because organisms with favored characteristics survive and reproduce more than ones without favored characteristics, and if these characteristics are heritable they will mechanically increase in frequency over generations. Although some evolutionary phenomena, such as genetic drift, are indeed random, these processes do not produce adaptations in organisms.

If the substance of this objection is that evolution seems implausible, that it's hard to imagine how life could develop by natural processes, then this is an invalid argument from ignorance. Something does not need to be intuitive or easy to grasp in order to be true. See also Past discussions

For further information, see the numerous past discussions on these topics in the archives of Talk:Evolution:

The article is not neutral. It doesn't mention that evolution is controversial.

The article should mention alternative views prominently, such as in a criticism section.

Evolution is just a theory, not a fact.

There is scientific evidence against evolution.

References
  1. See List of scientific societies rejecting intelligent design.
  2. As reported in Newsweek magazine, 29 June 1987, Page 23: "By one count there are some 700 scientists with respectable academic credentials (out of a total of 480,000 U.S. Earth and life scientists) who give credence to creation-science..." See also Public beliefs about evolution and creation, Robinson, B. A. 1995. for a discussion on acceptance of evolution.
  3. ^ The Origin of Whales and the Power of Independent Evidence
  4. Dobzhansky T, Pavlovsky O (1971). "An experimentally created incipient species of Drosophila". Nature. 230 (5292): 289–292. doi:10.1038/230289a0. PMID 5549403.
  5. DM Hillis; JJ Bull; ME White; MR Badgett; IJ Molineux (1992). "Experimental phylogenetics: generation of a known phylogeny". Science. 255 (5044): 589–592. doi:10.1126/science.1736360. PMID 1736360.
  6. Crandall, K. (1994). "Intraspecific cladogram estimation: Accuracy at higher levels of divergence" (PDF). Systematic Biology. 43 (2): 222–235.
  7. Gates, Reginald Ruggles (September 1909). "The Behavior of the Chromosomes in Oenothera lata x O. gigas". Botanical Gazette. 48 (3): 179–199. doi:10.1086/329990. JSTOR 2467513.
  8. Herrel, A.; Huyghe, K.; Vanhooydonck, B.; Backeljau, T.; Breugelmans, K.; Grbac, I.; Van Damme, R.; Irschick, D. J. (2008). "Rapid large-scale evolutionary divergence in morphology and performance associated with exploitation of a different dietary resource". Proceedings of the National Academy of Sciences. 105 (12): 4792–5. doi:10.1073/pnas.0711998105. PMC 2290806. PMID 18344323.
  9. Cressey, Daniel (2009). "Darwin's finches tracked to reveal evolution in action". Nature. doi:10.1038/news.2009.1089.
  10. Hunt, Kathleen (1997). Transitional Vertebrate Fossils FAQ. TalkOrigins Archive.
  11. Elsberry, Wesley R. (1998). Missing links still missing!?
  12. Lambert, Frank (2002). "Disorder — A Cracked Crutch For Supporting Entropy Discussions". Journal of Chemical Education. 79: 187–192. Retrieved 15 July 2015.
  13. Does Life On Earth Violate the Second Law of Thermodynamics?
  14. Lamb, Trevor D.; Collin, Shaun P.; Pugh, Jr, Edward N. (2007), "Evolution of the vertebrate eye: opsins, photoreceptors, retina and eye cup", Nature Reviews Neuroscience, 8: 960–976
  15. Isaak, Mark (2005). Index to Creationist Claims, Claim CB200: Irreducible complexity. TalkOrigins Archive.
  16. Robison, Keith (1996). Darwin's Black Box: Irreducible Complexity or Irreproducible Irreducibility?. TalkOrigins Archive.
  17. Musgrave, Ian & Baldwin, Rich, et al (2005). Information Theory and Creationism. TalkOrigins Archive.
  18. "Evolution and Information: The Nylon Bug". New Mexicans for Science and Reason.
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WarningWARNING: This is not the place to discuss any alleged controversy or opinion about evolution and its related subjects. This page is for discussing improvements to the article, which is about evolution (not creation science, not creationism, and not intelligent design to name a few), and what has been presented in peer-reviewed scientific literature about it. See Misplaced Pages:No original research and Misplaced Pages:Talk page guidelines. Some common points of argument are addressed in the FAQ above, which represents the consensus of editors here. If you are interested in discussing or debating over evolution itself, you may want to visit talk.origins or elsewhere.
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How do I get permission to edit this article?

There are lots of things that need fixing but I have to become an "autoconfirmed user" in order to edit this article. How do I do that?

The first thing that need to be changed is the second sentence which now reads, "These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction."

This is misleading since gene expression refers to the molecular gene while this article is talking about the Mendelian gene. Evolution can be due to changes in the allele frequencies of junk DNA so we need to make sure people understand that we aren't restricting evolution to changes in the frequencies of alleles in molecular genes.

I suggest, "These characteristics are traditionally referred to as Mendelian genes or changes in DNA sequences that are passed on from parent to offspring during reproduction." Genome42 (talk) 19:01, 14 July 2023 (UTC)

@Genome42 You are already autoconfirmed, having made well over the threshold for that status. (See WP:AUTOCONFIRMED.) So you can go ahead and be WP:BOLD but should be prepared to discuss your changes here if reverted (per WP:BRD). This is a featured article, so it has been extensively reviewed by experienced editors but that doesn't mean it can't be improved! Mike Turnbull (talk) 19:13, 14 July 2023 (UTC)
P.S. You are proposing a change to the WP:LEAD of the article, which as that link explains should be a section which is a concise overview of the content given in full detail later on. Hence you need to check that your new text is consistent with what is written in the main part. Mike Turnbull (talk) 22:01, 14 July 2023 (UTC)
The most important problems with this article are: (1) it focuses too much on "genes" as the only target of evolutionary change, (2) it ignores or dismisses molecular evolution and even makes the false claim that the neutral theory has been "abandoned," (3) it ignores population genetics and doesn't describe any of the fundamental equations that form the basis of modern evolutionary theory, (4) it fails to make a clear distinction between evolution as a process and the history of life, which is explained by evolution, (5) it doesn't deal with the issue of adaptationism, which is responsible for much of the misunderstanding of evolution, (6) it does not explain macroevolution correctly, (7) it gets the history of evolutionary theory wrong and ignores the real controversy over the modern synthesis, (8) it doesn't mention levels of selection and hierarchy theory.
The lead is bad for several reasons but the most important is that it doesn't put enough emphasis on the current definition of evolution. It also emphasizes natural selection and downplays random genetic drift in spite of the fact that drift is the main mechanism of evolution. It has a paragraph devoted to the history of life which contains data, not a summary. It is too long - the second paragraph should be deleted.
The figure at the top of the page is incorrect. It depicts the history of life according to the Three Domain Hypothesis but that view was discarded more than 20 years ago. We now know that eukaryotes arose as a fusion between a protobacterium and a species within the Archaea.
According to Misplaced Pages, "Featured articles are considered to be some of the best articles Misplaced Pages has to offer, as determined by Misplaced Pages's editors." I don't think this qualifies as the best we can do. Let's make it better. Genome42 (talk) 22:09, 15 July 2023 (UTC)

Change the lead

@Efbrazil Please see my suggestions above for changing the lead. I think they are reasonable and necessary. There are two kinds of genes: Mendelian and molecular. The Mendelian gene is any bit of DNA that plays a role in evolution. It includes things like regulatory sequences, origins of replication, centromeres, and chromosome rearrangements. The molecular gene is the DNA sequence that is transcribed to produce a functional RNA (see Gene).

When you talk about “expression” of a gene you are referring to the molecular gene but the lead is actually talking about the Mendelian gene, not the molecular gene. Later in the article we should be discussing molecular evolution, which can be changes in alleles in junk DNA so perhaps we should avoid any mention of gene in the lead and only refer to changes in allele frequency. Maybe we should define heritable changes correctly as any change in DNA sequence? Genome42 (talk) 09:48, 16 July 2023 (UTC)

Anybody who is coming here to learn about the basics of what "evolution" is certainly isn't going to have any clue what "Mendelian" means. We need to keep the reading level of the lead in a basic article like this at an elementary school level, especially the first paragraph or two, which is all most people will ever read or understand. If you believe substance needs to be changed, please suggest text that is jargon free and could be understood by most english speaking fifth graders. If you want to write something below I could look to wordsmith it with you. Efbrazil (talk) 18:52, 16 July 2023 (UTC)
Also, to be clear, the existing lead already has too much jargon. I just went in and tried to cut some of the most unnecessary bits out. Readability checkers say the text requires a college graduate level of education to understand. Here is how ChatGPT rewrites the lead at a middle school level. I'm not saying we adopt this, but it has some interesting simplifications:
Evolution is a process in biology where characteristics in living things change over time. These characteristics come from genes that are passed down from parents to their offspring. Genetic variation happens because of mutations and recombination. Evolution occurs when things like natural selection and genetic drift act on this variation, causing certain traits to become more or less common in a population over generations. This process of evolution is responsible for the diversity of life we see in different levels of biology.
The theory of evolution by natural selection was developed by Charles Darwin and Alfred Russel Wallace in the mid-19th century. They observed certain facts about living organisms that support this theory. First, more offspring are produced than can survive. Second, individuals have different traits in terms of their physical characteristics, how their bodies work, and their behavior. Third, these traits affect how likely individuals are to survive and have offspring. Finally, traits can be passed on to future generations. This means that over time, individuals with favorable traits are more likely to have offspring, replacing those with less favorable traits. In the early 20th century, other ideas about evolution were disproven as scientists found evidence that supports Darwin's theory.
All life on Earth, including humans, shares a common ancestor that lived billions of years ago. This can be seen in the fossil record, which shows a progression from simple life forms to more complex organisms. The diversity of life we see today is a result of new species forming, changes happening within species, and species going extinct throughout Earth's history. Similarities in physical and biochemical traits can tell us how closely related species are and help us create family trees.
Evolutionary biologists continue to study different aspects of evolution by making hypotheses, testing them, and creating theories based on evidence from the field or lab. Their discoveries have had a big impact not only on biology but also on other fields like agriculture, medicine, and computer science. Efbrazil (talk) 20:18, 16 July 2023 (UTC)
There’s no way we can write this article for fifth graders. Evolution is a controversial topic and there are lots of misconceptions that we have to deal with. Let’s start with the definition. The two most important points are change in heritable characteristics and the fact that it is populations that evolve. The correct definition should be in the first sentence. (ChatGPT doesn’t understand the correct definition.)
“Heritable characteristics” requires expansion but we need to avoid confining them to genes because that’s not correct. How about just saying “heritable characteristics are changes in the DNA sequence”?
We also need to avoid phrases like “characteristics are passed down from parents to their offspring.” That doesn’t make a lot of sense when you are talking about bacteria, algae, mushrooms, and maple trees. There no reason to perpetuate such misleading baby talk in a scientific article on Misplaced Pages. Genome42 (talk) 20:47, 16 July 2023 (UTC)
Sorry, I don't think I was clear. I'm not trying to suggest we rewrite the whole thing to be fifth grade level or adopt chatgpt's take on things. I just think we should try to take out jargon and shorten sentences whenever possible. Adding a distinction between molecular and Mendelian genes is not really where this article needs to start.
Going back to the edit you made previously, we could strike out "traditionally referred to as Mendelian genes or ". That would leave your edit as changing this:
These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction.
to this:
These characteristics are changes in DNA sequences that are passed on from parent to offspring during reproduction. The most important points in the modern definition of evolution are that changes have to be heritable (genetic) and that it is populations that evolve and not individuals.
There are still problems in that new text. First, it is longer and the lead is overlong already. Second, you say "These characteristics are changes in DNA sequences", but I don't think DNA sequence changes can be equated to characteristics like that, so we could change that to say "These characteristics are caused by changes in DNA sequences", but then it feels like we are dancing around saying the word "genes", and the following sentence in the existing text begins with genetics.
The second new sentence you wrote is a major claim and pretty long winded. I don't see the value in including it except in defining the word "genetic", which is grounding the following sentence needs. All you say though is genetic = heritable, which is pretty iffy. The existing wording is better I think, even if it lacks the precision you want. The statement that populations evolve and not individuals is I think pretty self evident and not worth mentioning at the outset like this.
So that's why I'm asking for a proposal and I'm trying to frame what I'll be looking for in your proposal. First, please don't add jargon. Second, please try and make things more concise than they are today rather than adding content.
Note I don't disagree with any of the high level points you are making in your critique of the article. We just need to be careful with the text in the lead. It may be more productive to start your work by making article modifications, then revisit the lead. You won't get nearly as much second guessing if you attack the article text :) Efbrazil (talk) 23:09, 16 July 2023 (UTC)
I’m not sure if you understand the problem. What we’re talking about is changes of frequencies of alleles in a population. Alleles are not genes and they are not confined to genes. Alleles are DNA sequences. Calling them “characteristics” is confusing but I understand the necessity of avoiding the proper scientific term (allele). What do you mean when you say that “I don’t think DNA sequences can be equated to characteristics”? What do YOU think these characteristics are if they aren’t alleles? Genome42 (talk) 03:29, 17 July 2023 (UTC)
In terms of defining characteristics, the lead in the second paragraph equates characteristics with traits, where it says traits are attributes of organisms that impact their ability to survive and reproduce- their behavior, morphology, or physiology. I think that is also the definition that most people opening this article will assume. Oxford dictionary defines an allele as "one of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome." Efbrazil (talk) 22:01, 17 July 2023 (UTC)
The second paragraph is a description of natural selection. It should not be in the lead, especially since random genetic drift isn’t explained as well. This paragraph uses an incorrect definition of traits and doesn’t explain how they relate to the heritable characteristics mentioned in the first paragraph.
The Oxford dictionary definition of allele is incorrect, see allele. Alleles are not restricted to genes.
These are exactly the kinds of misconceptions that Misplaced Pages was designed to correct. Genome42 (talk) 04:36, 18 July 2023 (UTC)
Misplaced Pages is designed to distill information from authoritative sources, like the oxford dictionary for instance. If there's more authoritative sources then I'm all for using those. Regardless, let me know if you can come up with new text that addresses your concerns while considering the issues I raised. Efbrazil (talk) 17:49, 18 July 2023 (UTC)
Do you intend to revert my edits unless I get your approval beforehand? Why? Do you think my suggestions aren’t scientifically accurate? Genome42 (talk) 18:07, 18 July 2023 (UTC)
If you submit the same text you did before then I'll revert it for the reasons I listed above. While small changes can just be made on wiki, large changes need to be wordsmithed and get buy in before they go live. What I recommend is you start a new section here on the talk page with the text changes you think are needed for the lead, so we can get to consensus. For more, see: Misplaced Pages:Dispute_resolution. Efbrazil (talk) 18:30, 18 July 2023 (UTC)
How about this for the complete new lead?
"In biology, evolution is the change in heritable characteristics of biological populations over successive generations. Genetic variation occurs within any given population as a result of mutation and recombination giving rise to a population where different individuals have different sequences of DNA at any one site on their chromosomes. These different variants are called alleles.
Evolution occurs when evolutionary processes such as natural selection (including sexual selection) and genetic drift act on this variation, resulting in certain alleles becoming more or less common within a population over successive generations. It is this process of evolution that has given rise to biodiversity at every level of biological organisation.
All life on Earth shares a last universal common ancestor (LUCA), which lived approximately 3.5–3.8 billion years ago. The fossil record shows a change from early biogenic graphite to microbial mat fossils to fossilised multicellular organisms. Existing patterns of biodiversity have been shaped by repeated formations of new species (speciation), changes within species (anagenesis), and loss of species (extinction) throughout the evolutionary history of life on Earth. Morphological and biochemical traits are more similar among species that share a more recent common ancestor, and these traits can be used to reconstruct phylogenetic trees." Genome42 (talk) 21:43, 18 July 2023 (UTC)
You need a new section for this proposal, and I think you should break it down into digestible changes rather than taking on the entire lead all at once. Clearly state your goal, then show how you want the text to change to meet that goal, then ask for support.
The current lead was the result of many editors working together over many weeks. See here for a history of lead discussion- it is in archives 59 to 64, and is quite endless: https://en.wikipedia.org/Talk:Evolution/Archive_64
My personal view is that the current lead is better than the text you are proposing for somebody who does not know what evolution is. Concepts need to be built up one after the other for an introductory article to a major topic like this. I think that ifGenome42 (talk) 21:04, 24 July 2023 (UTC) the text you are proposing was taken to a middle schooler they would not understand it. This article needs to be as accessible as possible. Efbrazil (talk) 18:33, 23 July 2023 (UTC)

@Efbrazil This is the thread where I proposed changes to the lead. Nobody but you has responded to my suggestions in the last 8 days. I stated my objections to the current version and I proposed changes to fix the mistakes.

You referred me to old discussions on changes to the lead but those discussions were not productive or informative. What's clear is that there have been many editors who objected to the older versions of the lead and even the current version. Clearly, there's a problem. There are many editors who point out that the definition "changes in allele frequency in a population" is the correct minimal scientific definition of evolution. They repeatedly make the point that words like "traits" and "heritable characteristics" are not suitable synonyms for "alleles." These objections are usually ignored or rejected on the grounds that the word "allele" is too technical for the average reader.

I see their point, so I tried to find a middle ground by keeping the current version but then immediately expanding it by introducing the word allele to explain heritable characteristics. I don't think there's any way to avoid the word "allele" in the lead since it is a necessary part of the article later on and because the term "heritable characteristics" can be very mispleading.

On Aug. 28, 2018 Danielkueh made extensive changes to the lead, mostly by reverting to the description that was used 20 years ago. He added the following sentence to the first paragraph of the lead, "These characteristics are the expressions of genes that have been passed on from parent to offspring during reproduction. " This was an attempt to further describe "heritable characteristics" but rather than use the acceptable scientific term "alleles" they used a different explanation that is indefensible as I explained above.

This is not really controversial if you know anything about the minimal definition of evolution. Alleles are NOT the expression of genes no matter how you define "gene."

I do not understand why anyone would object to removing this incorrect statement. Here is my proposal for the first two paragraphs. It explains that heritable characteristics are alleles and it eliminates the misleading "expression of genes" statement. It then describes evolution as a change in allele frequency. I'm anxious to hear from any editor who has serious objections to my proposal. I'd like to point out that the most important goal in a scientific article is accuracy and we should never sacrifice scientific accuracy for readability.

"In biology, evolution is the change in heritable characteristics of biological populations over successive generations. Genetic variation occurs within any given population as a result of mutation and recombination giving rise to a population where different individuals have different sequences of DNA at any one site on their chromosomes. These different variants are called alleles.
Evolution occurs when evolutionary processes such as natural selection (including sexual selection) and genetic drift act on this variation, resulting in certain alleles becoming more or less common within a population over successive generations. It is this process of evolution that has given rise to biodiversity at every level of biological organization."

Genome42 (talk) 21:04, 24 July 2023 (UTC)

Thanks for reviewing the lead editing history. I think the new text you are proposing is better as you are defining the word allele, but I think the first paragraph is the wrong spot to put that idea.
What is more relevant to someone learning about evolution- the ideas of heredity and natural selection, or the idea of alleles? The more relevant and accessible ideas should be put first. We can either hand wave dna and genetics in the first paragraph as happens now, or get more technical with that content and put it later in the lead.
If you want input from more people, you can use the ping template. Typically once there is a long discussion like this people don't just jump in. That's why I was suggesting a new section with a proposal, particularly if you disagree with my critiques or want a fresh perspective. Efbrazil (talk) 17:59, 26 July 2023 (UTC)
You ask an important question, "What is more relevant to someone learning about evolution- the ideas of heredity and natural selection, or the idea of alleles?"
The answer is not as straightforward as you might think. The idea of "heredity" is important but it's just as important to explain what it is that's inherited. It's not things like zebra stripes, big brains, and the size of finch beaks. It's the DNA that's responsible for those characteristics that's inherited as well as many other segments of DNA that don't even express a phenotype. It's alleles that are inherited.
Most of our readers don't know this because they have been taught simplified and misleading information about evolution. That's why it's important to start correcting this misinformation right from the start.
Same with natural selection. Most people think that the only mechanism of evolution is natural selection but that's something that we have to correct as soon as possible in this article. In order to do that, we have to steer readers away from the old-fashioned, and incorrect, view that evolution is only concerned with very visible phenotypic changes in animals.
I will start a new thread to see if anyone else wants to comment. Genome42 (talk) 21:08, 26 July 2023 (UTC)

New proposal for the first two paragraphs of the lead.

I propose to change the lead to,

"In biology, evolution is the change in heritable characteristics of biological populations over successive generations. Genetic variation occurs within any given population as a result of mutation and recombination giving rise to a population where different individuals have different sequences of DNA at any one site on their chromosomes. These different variants are called alleles.

Evolution occurs when evolutionary processes such as natural selection (including sexual selection) and genetic drift act on this variation, resulting in certain alleles becoming more or less common within a population over successive generations. It is this process of evolution that has given rise to biodiversity at every level of biological organization."

Genome42 (talk) 21:11, 26 July 2023 (UTC)

To clarify, it looks like you are suggesting replacing the first paragraph that is there now with these two paragraphs (you are not suggesting we replace the first two paragraphs of the lead). I hope more people comment. If not, I encourage you to submit an RfC or use the ping template.
  • Oppose: My main concern with this proposal is that the second sentence is a jumble of ideas that doesn't connect back to the first sentence the way the current text does. I don't think someone unfamiliar with evolution is going to be able to handle a sentence with genetic variation, mutation, recombination, dna, "giving rise to a population", and chromosomes all at once. What is currently on site does a good job of building up concepts one at a time. It goes from characteristics --> genes, then genes --> genetic variation, then genetic variation --> natural selection, and finally natural selection --> biological diversity. Regarding your core idea of talking about alleles instead of genes and genetic diversity, I have no basic objection, but it does complicate the lead to introduce jargon like that. Genes are the more common term and connect to genetics. An alternative would be to omit all mentions of genes and alleles and genetics and chromosomes simply talk in terms of DNA. That other stuff can come later.
Efbrazil (talk) 20:21, 28 July 2023 (UTC)
Let me try one more time to explain why your reasoning is scientifically inaccurate.
You like the idea of describing “characteristics” as the expression of genes as in the current lead. This is not correct and it’s embarrassing to see this in a Misplaced Pages article on evolution. I have explained this many times. The best way to argue in favor of the current lead is for you to find an scientific source that says evolution is restricted to changes in the expression of genes. Good luck with that.
You like the idea of a progression of concepts that lead to natural selection and then “natural selection —-> biological diversity.” But this is scientifically incorrect in the sense that there’s more to evolution than natural selection. In fact, the rest of the article explains that random genetic drift is an important mechanism of evolution. That concept is even in the current lead. Most biological diversity at the molecular level is due to neutral alleles and random genetic drift. One could make a good case that a lot of biological diversity at the gross phenotypic level is also not adaptive (i.e. not due to natural selection).
One of our goals should be to explain the correct scientific concepts and not to cater to the standard misconceptions that most people have about evolution. Genome42 (talk) 10:37, 29 July 2023 (UTC)
"These characteristics are the expressions of genes" can be interpreted to include which genetic variant is being expressed. It doesn't necessarily mean which genes are turned on and off.
Having said that, I'm really not defending the current text. I care primarily about having any changes be more accessible, not less. Shorter sentences, less jargon, connected ideas that build up a mental model.
If you want text that is both accessible and less open to misinterpretation, we could simply cut those two sentences from the first paragraph. For instance, the first paragraph could be changed to this:
In biology, evolution is the change in heritable characteristics of biological populations over successive generations. Evolution occurs when evolutionary processes such as natural selection (including sexual selection) and genetic drift act on heritable characteristics, resulting in certain characteristics becoming more or less common within a population over successive generations. It is this process of evolution that has given rise to biodiversity at every level of biological organisation.
We could then cut the last parargaph of the lead entirely (it's fluff) and create a new paragraph beginning with "In the early 20th century, other competing ideas of evolution were refuted as the modern synthesis concluded Darwinian evolution acts on Mendelian genetic variation." That would give us the opening to talk about genetics. Efbrazil (talk) 17:39, 31 July 2023 (UTC)
I don’t think you are paying attention to what I’ve been saying. A lot of evolution is due to the fixation of neutral alleles and in many organisms these neutral alleles are not in genes. Thus, there’s no way that heritable characteristics can be defined as which genetic variant is being expressed because nothing is being expressed.
I agree with your proposed change to remove the incorrect sentence. It’s too bad that it took so long to reach agreement on such an obvious correction to the current lead. Genome42 (talk) 00:32, 1 August 2023 (UTC)
Yes, junk DNA is not junk, but it's also true that genetic variation is what leads to variability in heriditary characteristics. I don't agree that the current sentence is incorrect, it's just that you're determined to read it that way.
Maybe as a path forward you could take what I suggested as a compromise and make a new proposal along those lines. If you can get people agreeing with your proposal it could move forward. So far, you don't have people agreeing with you. And again, if you want more voices because you think I'm off base, use the ping template. Efbrazil (talk) 03:17, 1 August 2023 (UTC)
I note that you don’t have people agreeing with you either. In fact, only one other person even cares to participate in this discussion. I don’t know what the “ping template” is or how to use it.
You seem determined to avoid reading the word “express” as in “expression of genes” and determined to avoid defending the idea that heritable characteristics can be defined as the expression of genes when we’re talking about the fixation of SNPs in junk DNA. Please try and come up with a scientific argument to defend the current lead. Find a scientific source that supports your view. Genome42 (talk) 08:52, 1 August 2023 (UTC)
Ping template Efbrazil (talk) 17:55, 1 August 2023 (UTC)
I agree with your suggestion to delete the second and third sentences of the lead. I will make the change. Genome42 (talk) 18:44, 3 August 2023 (UTC)
Good, progress! I tried to build on what you did by adding in a variant of your wording into that spot in the lead I was previously talking about. Take a look and make changes as you see fit. I think it is best if we simply talk DNA and try to avoid "allele", "gene", and "chromosome". All those words are really just about how DNA gets converted into physical characteristics. Efbrazil (talk) 19:32, 3 August 2023 (UTC)
  • I still don't get the aversion to the word "gene". An allele is a variant of some gene, so calling it a gene is not exactly incorrect, maybe less specific sure. And if we're not using the word "allele", then there's no reason to further complicate the word "genetics" with Mandelian or molecular genetics or population genetics, etc., since the entire thing boils down to just how many alleles a gene could have, which is really outside the scope of at least the lede Dunkleosteus77 (talk) 01:46, 29 July 2023 (UTC)
    A lot of evolution at the molecular level takes place outside of genes. Even phenotypic changes are often due to changes in regulatory sequences and they are not part of the molecular gene. Alleles are not only found in genes but in all kinds of DNA sequences, including junk DNA. It’s the frequency of alleles that change and not just the frequency of (molecular) gene variants.
    Some of the major misconceptions in evolution have to do with confusion over the meaning of “gene,” as in “gene-centric” view of evolution, and over the role of random genetic drift. It will be far easier to correct these misconception if we introduce the correct scientific terms as soon as possible. Genome42 (talk) 10:12, 29 July 2023 (UTC)
None of these are opposing concepts Dunkleosteus77 (talk) 21:21, 29 July 2023 (UTC)
I have no idea what you mean by “opposing concepts.” If you say that the heritable characteristics are the expression of genes and I say that’s not correct then those seem to be opposing concepts to me.
If you say that evolution is defined as changes in genes and I say that’s not true then those sure seem like opposing concepts to me.
If you define an allele as a gene variant and I say that you can have alleles that are outside of genes then how are those not opposing concepts? Genome42 (talk) 03:03, 30 July 2023 (UTC)
  • Maybe we should just use the words of an expert by quoting the definition/description in the leading textbooks. Here's an example from one of the best textbooks on evolution. Does anyone object to putting this in the opening paragraph of the lead? Later on in the article we can explain that alleles aren't confined to genes and that evolution embraces other slight changes that are outside genes?
"Biological (or organic) evolution is change in the properties of populations of organisms ..., over the course of generations. The development, or ontogeny, of an individual organism is not considered evolution: individual organisms do not evolve. The changes in populations that are considered evolutionary are those that are ‘heritable' via the genetic material from one generation to the next. Biological evolution may be slight or substantial; it embraces everything from slight changes in the proportions of different forms of a gene within a population, such as the alleles that determine the different human blood types, to the alterations that led from the earliest organisms to dinosaurs, bees, snapdragons, and humans."
Douglas J. Futuyma (1998) Evolutionary Biology 3rd ed., Sinauer Associates Inc. Sunderland MA p.4
I gather that many editors would be uncomfortable with the definition used by one of the best biology textbooks of all time even though this is the definition that was taught to generations of undergraduates.
"In fact, evolution can be precisely defined as any change in the frequency of alleles within a gene pool from one generation to the next."
Helena Curtis and N. Sue Barnes, Biology, 5th ed. 1989 Worth Publishers, p.974
Keep in mind that our goal is to define/describe evolution in a way that encompasses all forms of evolution. It's especially important to include molecular evolution since that's the focus of much scientific activity these days and because it's the form of evolution that's the least understood by the general public (and creationists).
The experts in molecular evolution (population geneticists) all agree with a definition similar to this,
"Evolution, according to this definition, is the process of change in the genetic makeup of populations, that is, a change in genotype and allele frequencies. By providing an exact and measurable definition of evolution we can apply strict scientific methodology to what is essentially a historical process."
Gruar, Dan (2016) "Molecular and Genome Evolution" Sinauer Associates Inc.
I don't understand why some editors are objecting to the proper scientific definition of evolution.
Genome42 (talk) 14:52, 29 July 2023 (UTC)

Citation for assertion that blending inheritance is incompatible with natural selection

I've seen this assertion repeatedly, but it is far from self-evident and I would like to see a citation to a proper quantitative analysis. The article on Blending inheritance cites a Guardian article by Richard Dawkins that dismisses a straw-man version of the model -- one that does not include the possibility of mutation. My intuition is that it may require strong selection to overcome the high mutation rate needed to maintain variation -- but that it would still work find under some circumstances. AdamChrisR (talk) 01:35, 3 August 2023 (UTC)

The statement is backed by 3 sources in the blending inheritance article, not just dawkins, but also and . I can't verify either source, but I admit I find the claim to be self evident. Do either of those sources work for you? Efbrazil (talk) 02:41, 3 August 2023 (UTC)
I agree with AdamChrisR that the statement in the article is far from self-evident (i.e. probably wrong). It's not true that variation would be "rapidly lost" by blending inheritance and I can easily imagine how natural selection selection could act on individuals in a population with differing blends of inherited alleles.
But that's not the main problem. The statement on blending inheritance doesn't belong in the introduction to a section on "Sources of variation" and it doesn't even belong elsewhere in the article. There's not much point in bringing up ideas that were rejected more than 100 years ago. Somebody should put it in the section on "History of evolutionary thought" if you think it's important.
I will delete the two sentences that refer to blending inheritance along with the following sentence that makes an incorrect statement about the Hardy-Weinberg equilibrium. The Hardy-Weinberg equation allows you to test whether the frequencies of two alleles that are present in a diploid population show evidence of selection on homozygotes and/or heterozygotes. The current statement in the article says, "The Hardy–Weinberg principle provides the solution to how variation is maintained in a population with Mendelian inheritance" and that's totally false. The only way to maintain variation is a population is by some form of balancing selection. In all other cases variation will be eliminated by selection and/or drift. Genome42 (talk) 18:16, 3 August 2023 (UTC)
That's a good point -- blending inheritance is really tangential to the topic. It may fit in the history section; I'll see if I can put it in there when I get down there. Regarding the other sources, I've only looked at the Larson source which quotes the Jenkin argument. The problem is that the Jenkin argument does not compare blending inheritance to Mendelian inheritance; the scenario presented by Jenkin would play out the same way under either model of inheritance. Specifically, according to modern theory, a single copy of an adaptive allele is still likely to go extinct -- if one migrant brings a set of adaptive alleles into a population, most of those alleles will go extinct rather than replacing everything. AdamChrisR (talk) 21:20, 12 August 2023 (UTC)

References

  1. Bowler 1983, pp. 23–26, 196–253. sfn error: no target: CITEREFBowler1983 (help)
  2. Larson 2004, pp. 105–129. sfn error: no target: CITEREFLarson2004 (help)

Removing description of natural selection from the lead

I mentioned earlier that the lead contained a description of natural selection and this shouldn't be there. I deleted it but Efbrazil immediately reverted my edit. They did not try to defend putting a description of natural selection in the lead while ignoring the other mechanisms of evolution that are described in the article.

Instead, Efbrazil says, "Undid revision 1168878355 by Genome42 (talk) This is too large a change to not run through the talk page first. Also, consider how a fifth grader will read what you have written in this edit- it is far too advanced for someone without background to understand. At least what was there was a hook for a fifth grader to begin to understand the concepts involved." That's a bizarre statement since I only added two extra words to what was already in the lead. Furthermore, this is a science article in an encyclopedia, not a book for fifth graders. Britannica and other encyclopedias do not write for fifth graders.

I'd also like to note, for the record, that the current description of natural selection is not very good in spite of the fact that this is supposed to be a featured article.

I intend to restore my edit unless someone can come up with a good reason why we should be explaining (poorly) the mechanism of natural selection in the lead to a large article on evolution that discusses many aspects of the subject. I'm confused about why Efbrazil is resisting the effort to make the article better without engaging in a serious discussion about the issues. Genome42 (talk) 21:25, 5 August 2023 (UTC)

Misplaced Pages is an educational tool that is used worldwide, principally on smartphones to look up basic facts. That is particularly true for a foundational article like this. We need to offer accessible content to someone new to evolution.
The existing text makes the foundational element of evolution clear to people without scientific education. Jumping straight into Mendelian inheritance, mutation, gene migration, and genetic drift without that grounding is going to confuse and alienate our audience.
Restoring reverted edits is warring, see WP:WAR. Efbrazil (talk) 16:25, 6 August 2023 (UTC)
I don't understand your reply. The text you are objecting to was already in the lead. (It's still there.) All I've done now is add "population genetics" and moved genetic drift to second place in the list. Do you want to remove that entire paragraph? Why?
Why haven't you replied to my proposal to delete the bad description of natural selection from the lead? That was the most important part of my edit - the one that you just reverted because it's not suitable for fifth graders.
I propose to remove it unless you can come up with a good reason for keeping it in the lead while ignoring random genetic drift, mutations, and gene flow.
Reverting reasonable edits with no attempt to discuss the science is warring. Please stop. Genome42 (talk) 17:09, 6 August 2023 (UTC)
Natural selection is foundational for understanding evolution and a clear description was put there for good reason. I don't see what is "bad" about the description. It just appears you want to see other evolutionary mechanisms more prominently discussed.
I am fine with mendelian genetics being talked about after we lay down the basics of natural selection. I have no objection to you adding a sentence on mendelian genetic mechanisms to that 3rd paragraph of the lead if that scratches your itch.
Again (and again), if you think I am off base then see WP:DR. Efbrazil (talk) 21:08, 6 August 2023 (UTC)
There are three kinds of natural selection: positive, negative (purifying), and balancing (see natural selection. The description in the lead only describes "favourable" selection. It lists four "facts" but only three principles are mentioned in the section on natural selection. The point about more offspring being produced than can possibly survive is not required for selection. Think about what happens when a growing population of bacteria is treated with a drug. (This needs to be corrected in the main body of the article.)
I'm not asking for the other mechanisms of evolution to be described in the lead. That would be just as inappropriate as picking only one of them. That kind of detail does not belong in the introduction to a comprehensive article on evolution - it will be covered in considerable detail in the rest of the article.
But there's a more important issue at stake. Most people have only a rudimentary understanding of evolution. They think that the only important thing worth knowing is some simplistic fifth grade understanding of positive natural selection. But evolutionary biology is much more sophisticated and complex than that and we owe it to our readers to disabuse them of their misconceptions. You can't fully understand evolution if you think that positive natural selection on big animals is all there is and you certainly can't challenge the facts of evolution if you think that's how real evolutionary biologists view evolution. Creationists make this mistake all the time and we need to correct that false view of evolution and teach everyone how scientists really think about evolution.
The current lead feeds into the common misconceptions of evolution by presenting a simplistic description of natural selection right up front in the lead, giving the impression that this is just about all you need to know. We can, and should, do better than that. Genome42 (talk) 15:16, 7 August 2023 (UTC)
I'm worried about your to and fro with Genome42 in relation to this article on Evolution, because I think you need to explain why you disagree with him. I should declare an interest as I agree with what he says, but even if I didn't I think he should be allowed make edits without having them reverted for no clearly stated reason. Genome42 is a highly respected Emeritus Professor of Biochemistry at the University of Toronto, the author of a major textbook, and of a more recent book on the genome. Your user page is extremely vague about your qualifications, but on your Talk page I read "I'm a liberal who lives in Seattle that has a graduate degree from UW and all that good stuff". OK, but a graduate degree at what level and in what subject? That doesn't of course mean that Genome42's opinion needs to be accepted without question, but it does mean that it should be taken seriously, not only by you but also by other editors of unknown qualifications who have reverted his edits to other pages. Athel cb (talk) 17:41, 8 August 2023 (UTC)
Please let's not get off track by reporting or calling for information about anyone's private lives. Misplaced Pages aims to report what experts have published. Qualifications should not be part of the discussion because that would mean we are talking about something beyond that mission, i.e. this is not the place to publish new research. Clearly the above discussion is however within our normal mission, and it is about how to report published information. No one seems to be debating complex technical matters. What I see is a discussion about how to present and break up the information.--Andrew Lancaster (talk) 19:18, 8 August 2023 (UTC)
Genome42, are you talking about Modern synthesis (20th century)? Dunkleosteus77 (talk) 01:39, 9 August 2023 (UTC)
@Dunkleosteus77 I’m talking about two things. (1) whether a description of positive natural selection needs to be in the lead, and (2) whether that description is the best we can do. So far, nobody has come up with a good reason for keeping a description of positive natural selection in the lead while ignoring other kinds of selection and other mechanisms of evolution. Do you have a good argument for keeping it?
We should have an explanation of the Modern Synthesis in the main body of the article along with a discussion about whether it is the current best model of evolutionary theory. Genome42 (talk) 03:17, 9 August 2023 (UTC)
@Andrew Lancaster Thank-you for joining the discussion. Please feel free to give us your opinion on how to improve this article. Genome42 (talk) 14:02, 9 August 2023 (UTC)
Thanks. At this stage I have neither taken a side nor come up with a proposal. I think I sort of understand why positive natural selection has a privileged position. If we think about how to write a lesson for example, we typically start with whatever concepts we think the students will be best able to lock onto as a starting point. Does that make any sense? Again, I am not taking a side, but just trying to think through the pros and cons.--Andrew Lancaster (talk) 15:20, 9 August 2023 (UTC)
@Andrew Lancaster Thank-you for taking sides and expressing an opinion. If I understand you correctly, you think we should retain a description of positive natural selection in the lead because that's what students expect to see when they consult the Misplaced Pages article on evolution. That only makes sense if the version that students can "lock onto" is the correct view of evolution.
Do you believe that's the best scientific view of evolution that we should be presenting in this article? What evidence do you have that this is the view described by experts in textbooks of evolutionary biology? The next paragraph in the lead says that evolution is a process that changes DNA in a population and the mechanisms are natural selection, genetic drift, mutation, and gene flow. Do you think that will confuse students who think that positive natural selection in animals is the only mechanism they expect to hear about?
If the rest of the article goes out of its way to describe other mechanisms of evolution then what's the point of emphasizing just one of them in the lead? Don't you think this could reinforce a common misunderstanding of evolution; namely, that it's all about positive natural selection? I've actually taught evolution and that's not how I wrote the lesson plan.
I believe that one has to have a deep understanding of the correct scientific view of a subject in order to edit/write a Misplaced Pages article. Do you agree or do you think we should cater to the common beliefs and not write articles that might challenge what students expect to hear? Genome42 (talk) 16:50, 9 August 2023 (UTC)
No, I did not take a side, and that's because I think the core of your concern is reasonable. The practical question is whether you are being so principled that it is counter productive. (Please also consider your talk page style. Your post is filled with leading questions and attempts to pin ideas on me which have nothing to do with anything I said. Don't treat people like idiots.) OTOH I'm not sure we need to take a side. A lead is different from the body. Whatever we write in the lead, it is not the body of the article and so I think we all agree that the lead does not need to explained everything. The most important thing is that the lead should not mislead or give a wrong impression.
Is this correct? You want readers of the lead to be alerted to the fact that there is more than one way in which natural selection works. You want us to be saying that "you might already know about X, but that is only one example". --Andrew Lancaster (talk) 21:27, 9 August 2023 (UTC)
Discussion of the editor's identity and qualifications is entirely appropriate in this case. He lists it on his User: and it's directly relevant to this article and questions of paedogogy. Invasive Spices (talk) 19:15, 9 August 2023 (UTC)
I don't see how this makes such sophistic debate strategies useful to the discussion. It is a distraction at best, and looks a bit deliberate. Let's just think through what is best for the article, as editors? I don't see anything particularly technical about this discussion.--Andrew Lancaster (talk) 21:27, 9 August 2023 (UTC)
@Andrew Lancaster I apologize. I though you were defending the idea that positive natural selection should have a “privileged position.” Are you okay with removing it from the lead and alerting readers that there are several important mechanisms of evolution?
BTW, do you agree that I’m not trying to publish new research in this article? I’m simply trying to explain basic principles that have been around for half a century. Genome42 (talk) 21:53, 9 August 2023 (UTC)
I wanted to say that I could understand and empathize with both ideas. (1) The idea that we use the most well-known example as a hook to open the article without making the lead too complex. (2) The argument that this might encourage a traditional over-simplification and misunderstanding. I don't see any reason (apart from polarizing styles of discussion) that both aims can't be considered, and possibly even used at the same time. For example in an article about early Frankish kings the lead might say "Frankish emperors, such as Charlemagne" (who is particularly well-known example). The wording here alerts readers to the fact that this is only an example. Such use of well-known examples does not need to create misunderstandings if the wording is well-chosen? Using illustrative examples is quite a normal way of writing even in academia.--Andrew Lancaster (talk) 22:01, 9 August 2023 (UTC)
This article is on an extremely broad subject that is introduced early in education. Our primary audience for this article is not graduate students, it is middle schoolers. If your concern is how qualified an editor is, I would suggest the best qualification would be a middle school science teacher. This article needs to be an appropriate WP:TECHNICAL level, favoring clarity over jargon. I do not want to see this article turn into Modern synthesis (20th century).
The article has already been through WP:FAR so it was very carefully constructed and reviewed. I did not write much of any of the content, but I think it should be protected against narrow perspectives demanding a complete rewrite. The changes Genome42 has demanded so far have been almost exclusively focused on the lead, ignoring the content of the article and holding previous lead content in contempt. I have been trying to guide them towards constructive inputs. Efbrazil (talk) 21:27, 9 August 2023 (UTC)
@EfbrazilCan you give me an example of an important science article on Misplaced Pages that’s written at the level of middle schoolers? Can you give me an example of a middle school science teacher who understands evolution well enough to write an encyclopedia article for Britannica or any other encyclopedia?
Also, I challenge you to find an evolutionary biologist who thinks this article is carefully constructed and accurate. I’ve already corrected a number of serious errors. I will continue to do so in order to make this article scientifically accurate unless I’m blocked by other editors. Genome42 (talk) 21:44, 9 August 2023 (UTC)
FWIW I agree that there is no need to write at middle school level. We should avoid errors, and simplifications are errors. Please let's not make unreasonable demands on each other. This discussions seems to be more difficult than it needs to be?--Andrew Lancaster (talk) 21:53, 9 August 2023 (UTC)

Fixing the lead (again)

The discussion is going nowhere so here are some small changes that will improve the lead a little bit.

The first paragraph has been fixed by removing the incorrect statement. The second sentence now reads, " Evolution occurs when evolutionary processes such as natural selection (including sexual selection) and genetic drift act on genetic variation, resulting in certain characteristics becoming more or less common within a population over successive generations."

The second paragraph emphasizes natural selection. It begins with, "The theory of evolution by natural selection was conceived ..." This is misleading because it confuses evolutionary theory with the mechanism of natural selection. By saying "The theory of evolution" we create two problem: (1) it plays into several common misconceptions such as natural selection is a theory (it's a fact) and there's only one theory of evolution, and (2) it conflicts with the third paragraph (see below).

I suggest we avoid these problems by just saying, "Natural selection was conceived ..." Please let me know if you object to this change and your reasons for objecting.

The third paragraph begins with, "In the early 20th century, competing ideas of evolution were refuted ..." This is confusing because genetic drift was not refuted - it was added to evolutionary theory along with mutation and gene flow. I realize that the existing sentence was referring to other ideas about evolution that were discarded but we don't really need to go there in the lead. The important point is that other ideas besides natural selection were added in the 20th century including the Neutral Theory and the Nearly-Neutral Theory. Also, it's not clear that mutationism has been refuted.

I suggest we edit this sentence so that the entire paragraph reads,

"In the early 20th century, natural selection was combined with Mendelian inheritance and population genetics and expanded to give rise to modern evolutionary theory. In this synthesis the basis for heredity is in DNA molecules that pass information from generation to generation and the processes that change DNA in a population include natural selection, genetic drift, mutation, and gene flow."

This has the added advantage of avoiding the misleading term "THE theory of evolution." Please let me know whether you agree with this change; if not, please offer another suggestion that will make the history more accurate. Genome42 (talk) 16:28, 10 August 2023 (UTC)

In your proposed paragraph, natural selection is being used a noun. Shouldn't it be an adjective? Something "natural selection theory"?--Andrew Lancaster (talk) 13:59, 13 August 2023 (UTC)
@Andrew Lancaster
Natural selection, genetic drift, mutation, and gene flow are all nouns and they are used as nouns in the main article; for example, "Natural selection can act at different levels of organisation, such as genes, cells, individual organisms, groups of organisms and species."
Chapter 4 of "Origin of Species" is titled "Natural Selection." Here's what Charles Darwin said, "This preservation of favourable variations and the rejection of injurious variations, I call Natural Selection."
Also, natural selection is a well-demonstrated fact, not a theory. Evolutionary theory proposes that populations evolve by the mechanisms of natural selection and random genetic drift (and other things).
Someone above suggested that, "This discussions seems to be more difficult than it needs to be?" and I agree with him. Genome42 (talk) 21:08, 13 August 2023 (UTC)
I think you have missed my point. In the sentence I am referring to you are not referring to the phenomenon, but rather the scientific narrative. Your word use is a kind of short hand, but I think technically wrong, not good for encyclopedic writing. Perhaps you missed my point because you seem very distracted about trying to avoid the word "theory". (Strangely "evolutionary theory" is ok for you, but not "theory of evolution".) Isn't this going along with the way creationists over-interpret that word? Why bother? Science does not demand finality about facts. It is made up of various types of narratives. I see no reason to apologise for using the word theory. Anyway, if you don't like the normal term for this narrative find another one but please distinguish the natural phenomenon from the accounts people make of it.--Andrew Lancaster (talk) 08:13, 14 August 2023 (UTC)
@Andrew Lancaster I think everyone needs to step back and look at the entire lead. I think it's too long, it contains information, such as a partial history of evolutionary theory, that doesn't belong in the introduction.
With the recent addition of adaptation it's even longer and the emphasis on the 18th century view of evolution has been strengthened.
The first paragraph correctly describes the current view of evolution and correctly identifies the two main mechanisms of allele frequency change; natural selection and genetic drift.
The next paragraph describes the 18th century history and contains a simplistic 18th century view of evolution by natural selection.
The third paragraph begins by stating that in the early 1900s competing ideas of evolution were refuted. What does that mean? The only idea other than natural selection that has been mentioned is genetic drift and it certainly wasn't refuted. It then says "evolution was combined with Mendelian inheritance and population genetics." What does "evolution" mean in this context? Does anyone think that makes sense? If not, why hasn't it been corrected and why is everyone being so critical of my attempt to fix it by saying "natural selection was combined with ..."?
We need to be very careful about saying "THE theory of evolution" (note the emphasis on "the"). That's because evolutionary theory is complex and controversial. It includes things like the neutral theory, the nearly-neutral theory, kin selection, the drift-barrier hypothesis, constructive neutral evolution, the gene-centric view of evolution, and many others. There is no single theory of evolution that justifies referring to THE theory of evolution.
In addition, by referring to "THE theory of evolution" we play into a major misconception that views the whole idea of evolution as just a theory. That's the view of evolution critics but it's also common among the rest of the general public. We know that evolution (change in allele frequencies) is a fact, not a theory, and I believe we have an obligation to explain this in the article. Genome42 (talk) 17:10, 14 August 2023 (UTC)
I actually can't parse the second sentence as it is proposed. Should the word 'include' be 'including', and perhaps be preceded by a comma? Girth Summit (blether) 15:15, 13 August 2023 (UTC)
That sentence does the reader no favors, running on at great enough length to obscure who does which, and with what, and to whom. A comma after "generation to generation" might make it clearer that "the processes ... include "
Just plain Bill (talk) 15:39, 13 August 2023 (UTC)
@Girth Summit,@Just plain Bill
Okay let's revert to the two sentences that are currently in the main article. I didn't think it was clear that the new modern evolutionary theory also proposed the inclusion of genetic drift, mutation, and gene flow. If you read it that way then it's okay. The paragraph will now read,
"In the early 20th century, natural selection was combined with Mendelian inheritance and population genetics and expanded to give rise to modern evolutionary theory. In this synthesis the basis for heredity is in DNA molecules that pass information from generation to generation. The processes that change DNA in a population include natural selection, genetic drift, mutation, and gene flow."
Genome42 (talk) 20:54, 13 August 2023 (UTC)
No complaint from me about carving that sentence into two digestible pieces. cheers! Just plain Bill (talk) 21:18, 13 August 2023 (UTC)

Adaptation

Shouldn't there be more emphasis on adaptation early in the article? It's the most obvious consequence of evolution and the one most people will think of, yet it isn't even mentioned until the section on the evolution of sexual reproduction. It's also missing from the introductory paragraphs of the Introduction to Evolution article.

I'm thinking of a first-paragraph sentence such as "The most dramatic outcome of evolution is adaptation, the fine-tuning of an organism's characteristics that enables it to grow and reproduce." Rosieredfield (talk) 21:19, 12 August 2023 (UTC)

Good point. I edited the second paragraph to note that natural selection was proposed as an explanation for adaptation (confirmed in the Intro of "Origin" that Darwin was motivated to explain "the coadaptations of organic beings to each other and to their physical conditions of life"). It may require more attention, but this is a start. AdamChrisR (talk) 23:36, 13 August 2023 (UTC)
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