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WARNING: 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 Wikipedia:No original research and Wikipedia:Talk page guidelines. Some common points of argument are addressed in the FAQ below, 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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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.
Wikipedia:Neutral point of view requires that minority views not be given undue emphasis.
Therefore it is against Wikipedia 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 [show] 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 Wikipedia'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 Wikipedia 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 Wikipedia 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 Wikipedia'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 Wikipedia 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.

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.^[1] In 1987 only about 0.15% of American Earth and life scientists supported creationism.^[2]

Thus, as a consequence of Wikipedia'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 Wikipedia'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.

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.

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.

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.^[3] 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.^[4] 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.^[5]^[6] Evolution has also been observed in the field, such as in the plant Oenothera lamarckiana which gave rise to the new species Oenothera gigas,^[7] in the Italian Wall Lizard,^[8] and in Darwin's finches.^[9]

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.^[3] So, although the entire evolutionary history of life has not been directly observed, all available data supports the fact 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.

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:

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.^[10]^[11]
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.^[12]^[13]
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.^[14] 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.^[15]^[16]
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.^[17]^[18]

With regard to the Wikipedia 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 Wikipedia knew that there was evidence against evolution, we could not add that information to the article without violating Wikipedia'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.

Suggestion and question

Suggestion: Lead: "...and can be used to reconstruct evolutionary histories, using both existing species and the fossil record." To: "...and can be used to reconstruct evolutionary histories, using traits from existing species and those of the fossil record."

Question: If: "Evolution is the change in the inherited characteristics of biological populations over successive generations." Then: "all change is the change of something: change presupposes something that changes. And it presupposes that, while changing, this something must remain the same. We may say that a green leaf changes when it turns brown; but we do not say that the green leaf changes when we substitute for it a brown leaf. It is essential to the idea of change that the thing that changes retains its identity while changing. And yet, it must become something else: it was green, and it becomes brown; it was moist, and it becomes dry; it was hot, and it becomes cold." (Popper, 1958-59, Proceedings of the Aristotelian Society) So: If inherited characteristics of biological populations change, such as brown transitioning to blue, how do the populations retain their identity while changing? I think evolution is both the retention of some characteristics and the change of others. If it was just change, then everything would fall apart over successive generations and obviously we still have populations of living fossils that evolved over successive generations. — Preceding unsigned comment added by 50.98.220.238 (talk) 04:06, 16 February 2013 (UTC)[reply]

Charles Darwin wrote: "Talking of “Natural Selection”, if I had to commence de novo, I would have used <natural preservation>"[1] If Darwin were to re-write the origin of species he would have used natural preservation over natural selection. If this twist of history had occurred, would the emphasis still be so high on change? If Darwin perceived preservation to be of such pivotal importance to his theory of evolution, why all the emphasis on change? Evolution is more the preservation of things, which is why Darwin focused on studying principles of heredity later in life. Evolutionary biologists study things that are preserved, i.e., homogenous:

"Structures which are genetically related, in so far as they have a single representative in a common ancestor, may be called homogenous. We may trace an homogeny between them, and speak of one as the homogen of the other...[homoplasy] includes all cases of close resemblance of form which are not traceable to homogeny, all details of agreement not homogenous, in structures which are broadly homogenous, as well as in structure having no genetic affinity" (Lankester, 1870; Annals and Magazine of natural History, 6, 35-43).

This means that evolutionary biologists study evolutionary theory (common ancestry) primarily through reference to homogens (homos=same, gen=kind) to trace lineal relations. Homoplasy is the stuff that changes and too much of it makes evolutionary trees intractable; e.g. [2]"Tests for Excessive Homoplasy (“Saturation”)". Far more traits are preserved than lost in the evolutionary process. Is this change? How are traits inherited (i.e., preserved) in the evolutionary process? By means of natural selection? Watson-Crick base-pairing? Varieties also do not imply change, because varieties may also be preserved (stabilizing selection), which is also part of evolution and has little to do with change. Several neutral varieties of cytochrome b may exist, they are neutral with respect to each other, which is unlike non-coding alleles or synonymous transitions that are neutral with respect to their phenotypic effect.

If: "Evolution is the change in the inherited characteristics of biological populations over successive generations" as stated in the lead, then how do evolutionary biologists account for the homogeny of inherited characterstics of biological populations? They do not reference a causal theory of change - that's for certain. "‘Change’ is not the pertinent quality of interest in evolution..."[3] It is the case of close resemblance (where change is not the thing of interest) that captures the imagination of evolutionary biologists and the rest of us. Take a look at our ape ancestors and the first thing you will find at a zoo is people chattering about how closely we resemble them - look at how similar we are!? The evolutionary transition of whales is so fascinating, because you can see the cline of preserved traits amongst fossilized relatives. The evolutionary intuition and fascination is not understood through reference to change, but to the natural preservation of things. This is how Darwin envisioned the theory (in his own words!), since when did it change and by whom?50.98.220.238 (talk) 06:17, 26 February 2013 (UTC)[reply]

Please do not delete edits of contributors making a sincere effort on the improvement of this article. Wikipedia is not to be censored. The above posts all provide citable reference material to back up the claims. They do not contest evolution - I am an evolutionary biologist by training. Darwin's concept of natural preservation is well known in the literature. The concept of change by Popper and other evolutionary biologists has been debated for many years in the primary and secondary literature. The post contains reliable information on evolutionary theory - it is not a creationst rambling about the unscientific nature of evolution. STOP THE CENSORSHIP.184.71.102.86 (talk) 22:21, 26 February 2013 (UTC)[reply]

Lankester was referenced above because he was the evolutionary biologist who derived the concept of homoplasy that is used so extensively in phylogenetics. The lead sentence can be literally translated into: "Evolution is homoplasy in the inherited characteristics of biological populations over successive generations" - because that is what the change refers to if read logically. The logic is inconsistent.184.71.102.86 (talk) 23:58, 26 February 2013 (UTC)[reply]

I don't have a problem with your argument but this article isn't about Darwinian evolution nor is there a discussion of his idea of pangenesis and gemmules. We presnt Natural Selection because that is what the literature associates with Darwin's contribution to evolution theory (that and common descent)-not natural preservation. You could argue common descent implies commonalities too. Then discuss the Modern Synthesis. But I agree "change" can be ambiguous. While populations exhibit commonalities you can also argue it is difficult to assign a defintion to a stereotypical species because variation is also just as obvious as commonalities. However I agree a phylogenetic perspective would strengthen this article-I would love for you and Thompsma to write a phylogenetic section for the article where you could address some of your concerns. The lead sentence has always been problematic so it always gathers critiques (I've done the same). Regards, GetAgrippa (talk) 02:38, 27 February 2013 (UTC)[reply]

"originated"

Just something to discuss. First sentence of second paragraph in lead: "Life on Earth originated and then evolved from a universal common ancestor approximately 3.8 billion years ago." It occurs to me that this sentence goes just a little bit out of its way for a lead sentence, concerning origins, and secondly that the question of origins of life and evolution are often mixed up by the less well read. We could consider changing to "Life on Earth ~~originated and then~~ evolved from a universal common ancestor approximately 3.8 billion years ago." Might that be more to the point?--Andrew Lancaster (talk) 20:39, 19 February 2013 (UTC)[reply]

Andrew, I have no problems with that suggestion. danielkueh (talk) 20:45, 19 February 2013 (UTC)[reply]

I like it. thx1138 (talk) 20:53, 19 February 2013 (UTC)[reply]

OK, discussion is of course never closed, but 2 votes makes me "bold" enough to put the edit in before retiring for the day.--Andrew Lancaster (talk) 21:20, 19 February 2013 (UTC)[reply]

Worthy NIH Study? => Life Began "10 Billion Years Ago"?

Should the following text/ref (or equivalent?) be included in the Evolution article?

In a National Institutes of Health study, the authors hypothesize that if biological complexity increased exponentially during evolution, life in the universe may have begun "10 billion years ago"< ref name="NIH-20060612">Sharov, Alexei A. (12 June 2006). "Genome increase as a clock for the origin and evolution of life". Biology Direct. 1: 1–17. doi:10.1186/1745-6150-1-17. PMC 1526419.{{cite journal}}: CS1 maint: unflagged free DOI (link)</ref> - more than 5 billion years before the Earth existed.

Related text and references may be found HERE - Thanks in any regards - and - Enjoy! :) Drbogdan (talk) 02:39, 1 March 2013 (UTC)[reply]

I don't really see that this specific speculation is notable enough to be in the lead. It is not even really about evolution per se.--Andrew Lancaster (talk) 11:53, 1 March 2013 (UTC)[reply]

To me, it reads a bit like a way to shoehorn a reference to life possibly not having begun on Earth into an article that isn't really concerned with that. I'd need to be convinced of the notability of the hypothesis for it to be included anywhere, but here notability isn't the issue - it's just not relevant to evolution. Cheers, Dawn Bard (talk) 16:40, 1 March 2013 (UTC)[reply]

Dawn, my feelings exactly. Aside from stylistic concerns, this hypothesis does not appear to be mainstream yet and I wonder if if qualifies as a fringe view. Plus it is primary source, which WP does not encourage. This reverted sentence has also been copied, verbatim, into several other articles (Life, Panspermia, Astrobiology) without much scrutiny. danielkueh (talk) 16:52, 1 March 2013 (UTC)[reply]

FWIW - the NIH study and related studies (also related, perhaps(?), my NYT comment) seem to be peer-reviewed and worthy to me at the moment - at least as a mention in appropriate articles - or - at the very least - worthy of discussion - re "not relevant to evolution" => seems to presume life began on earth - this may (or may not) be the case - if life began elsewhere - why would evolution no longer be relevant? - I agree, the material may not be "mainstream" at the moment - but then - neither were (as several examples) heliocentrism, continental drift or even evolution itself - at least at one time (and perhaps even currently for some?) - nonetheless, please understand that my position w/ this material is flexible - *entirely* ok w/ me to rv/mv/ce the material of course - in any case - Enjoy! :) Drbogdan (talk) 19:37, 1 March 2013 (UTC)[reply]

This is highly fringe and WP:PRIMARY, even the reviewers comments are not entirely convinced and some outright say it's flawed. To even CONSIDER adding this you're going to need WP:SECONDARY sources, i.e. academic reviews. — raeky t 22:52, 1 March 2013 (UTC)[reply]

Thank you for your comments - seems present consensus may be that the NIH Study may not be sufficiently settled at the moment to present - at least in the Evolution article - as before, rv/mv/ce the material is *entirely* ok with me - affected articles (mostly ledes) include: Abiogenesis, Astrobiology, Biogenesis, Extraterrestrial life, Life and Panspermia - although the original write-up in the Panspermia article may still be ok I would think - nonetheless (and if interested) several *possibly* relevant references may be as follows:

< ref name="SSR-201010">Wesson, Paul S. (October 2010). "Panspermia, Past and Present: Astrophysical and Biophysical Conditions for the Dissemination of Life in Space". Space Science Reviews. 156 (1–4): 239–252. doi:10.1007/s11214-010-9671-x. Retrieved March 2, 2013.</ref>
< ref name="SP-20110114">Vieru, Tudor (January 14, 2011). "Life Is 10 Billion Years Old". Softpedia. Retrieved March 1, 2013.</ref>
< ref name="TDG-20110131">Kazan, Casey (January 31, 2011). "When Did Proto-Life Emerge in the Universe?". "The Daily Galaxy". Retrieved March 1, 2013. {{cite web}}: Italic or bold markup not allowed in: |publisher= (help)</ref>

In any regards - Thanks Again - and - Enjoy! :) Drbogdan (talk) 03:16, 2 March 2013 (UTC)[reply]

Actually there was a Science article a few years back looking at tRNA and molecular clock of the genetic code and they found it to be about the same age as the origin of earth-which predates life on earth by fossil record of bacteria. But that influences abiogenesis and isn't related to evolution. GetAgrippa (talk) 23:00, 2 March 2013 (UTC)[reply]

Regarding user feedback requests for simpler information

I see that there's a notice at the top pointing towards Introduction to evolution as a "generally accessible and less technical" introduction to this topic. Would it be prudent to suggest readers also try reading "Simple English" Evolution? E.g., add something like For a simpler version of this page, consider reading in Simple English.

My thought is that the simple English version would satisfy the requests to make this more accessible to children. Havensfire (talk) 13:19, 8 March 2013 (UTC)[reply]

Maybe not a bad idea, but probably this is something not so relevant to this talk page but perhaps to the broader community somewhere: All articles with a simple English version do of course show a link indicating this, but should technical article positively advertise it a bit more? (Perhaps in the way that we advertise that wikisource or wiktionary have relevant materials?) Maybe discuss at WP:VP.--Andrew Lancaster (talk) 13:32, 8 March 2013 (UTC)[reply]

I'd like to suggest this, but don't know which section of Village Pump to put it in (new to taking a more active role in wikipedia). Should this go to the "Idea Lab?" Havensfire (talk) 15:50, 8 March 2013 (UTC)[reply]

Edit request on 10 March 2013

This edit request has been answered. Set the |answered= or |ans= parameter to no to reactivate your request.

Please include Theory of Evolution as the title. Still not proven there is a lot of guess work and assumptions thrown about when evoluitionary scientists speak about the subject. Mur838 (talk) 01:14, 10 March 2013 (UTC)[reply]

Not done. See FAQ #3. Acroterion (talk) 01:24, 10 March 2013 (UTC)[reply]

Al-Jahiz and the Arab contribution

My addition of Al-Jahiz in the history of evolution section has been deleted twice now. I was directed to talk about it here.

The first deletion had the reason that quality secondary sources had to be given. I created a new edit with quality secondary sources, and then it was deleted again, this time with no actual reason given.

I note that the Arab contribution has been completely omitted in this article, and my attempts to rectify this are currently being resisted.

Here is my latest addition, which was deleted with no actual reason given.

The 9th century Afro-Arab scholar Al-Jahiz, in his "Kitab al-Hayawan" ("The Book of Animals") introduced the idea of food chains and the struggle for existence.^[1]^[2]^[3]^[4]^[5]

I'm not sure if all the references will show up, so here are the references I provided, without the (ref)(/ref) tags.

C. Zirkle, "Natural Selection before the 'Origin of Species'", Proceedings of the American Philosophical Society, 84: 71 (1941).
M. Bayrakdar, "Al-Jahiz and the Rise of Biological Evolution", Islamic Quarterly, 21: 149 (1983).
F. N. Egerton, "A History of the Ecological Sciences, Part 6: Arabic Language Science—Origins and Zoological Writings", Bulletin of the Ecological Society of America, April 2002, p. 142.
P. S. Agutter and D. N. Wheatley, Thinking About Life: The History and Philosophy of Biology and Other Sciences, p. 42 (Springer, 2008).
H. Chaabani, "Insights on the history of Anthropology: its emergence in the wider Middle East before it existed as a discipline", International Journal of Modern Anthropology, 5: 80 (2012).

Here is a partial translation from Al-Jahiz's book of animals, where he talks about food chains and the struggle for existence. (I did not include this in my edit; I just include it here as further illustration of Al-Jahiz's ideas.)

C. Zirkle writes the following in the Proceedings of the American Philosophical Society.

"Here Al-Jahiz describes the struggle for existence:

"The rat goes out to look for its food, and is clever in getting it, since it eats all animals inferior to it in strength, such as little animals and small birds, the eggs and the young of the latter, and in general, the vermin which do not live in burrows or whose nests are flush with the earth. In its turn, the rat has to avoid snakes and birds and serpents of prey, who look for it in order to devour it. It must also be skillful in defending itself from the lizard and from the herizo, which are stronger than it is. The lizard is clever in hunting the snake and the fox. The latter in its turn, hunts all animals inferior to it. The mosquitoes go out to look for their food as they know instinctively that blood is the thing which makes them live. As soon as they see the elephant, hippopotamus or any other animal, they know that the skin has been fashioned to serve them as food; and falling on it, they pierce it with their probosces, certain that their thrusts are piercing deep enough and are capable of reaching down to draw the blood. Flies in their turn, although they feed on many and various things, principally hunt the mosquito which is the food which they like best. If it were not for the flies, the hum of mosquitoes during the day would be much greater. The star-lizard and the spider, called ant-lion, go out and hunt flies with the cleverest technique and greatest dexterity. But in addition, flies disappear also through the medium of other causes, for example, they die upon eating in competition over the sweet morsels. All animals, in short, can not exist without food, neither can the hunting animal escape being hunted in his turn. Every weak animal devours those weaker than itself. Strong animals cannot escape being devoured by other animals stronger than they. And in this respect, men do not differ from animals, some with respect to others, although they do not arrive at the same extremes. In short, God has disposed some human beings as a cause of life for others, and likewise, he has disposed the latter as a cause of the death of the former."

(Quoted from C. Zirkle, "Natural Selection before the 'Origin of Species'", Proceedings of the American Philosophical Society, 84: 71 (1941) - this is specifically from p. 85.)

P. S. Agutter and D. N. Wheatley say the following. "In biology, Al-Jahiz (c.781-868) introduced the concept of food chains, which had no known precedent in Greek or Persian thought, and also proposed a scheme of animal evolution that entailed natural selection, environmental determinism and (possibly) the inheritance of acquired characteristics." (Quoted from P. S. Agutter and D. N. Wheatley, Thinking About Life: The History and Philosophy of Biology and Other Sciences, p. 42 (Springer, 2008).)

F. N. Egerton writes the following in the Bulletin of the Ecological Society of America. "Bayrakdar's case for al-Jahiz being an evolutionist is unconvincing, but his narrower claim that he 'recognized the effect of environmental factors on animal life' (1983:151) seems valid. Apparently, al-Jahiz was the first to discuss food chains, although his details are not always accurate." Egerton then goes on to further quote part of the translation from Zirkle, which I quoted above, then says, "This is the earliest known description of a food chain." (F. N. Egerton, "A History of the Ecological Sciences, Part 6: Arabic Language Science—Origins and Zoological Writings", Bulletin of the Ecological Society of America, April 2002, p. 142 - this quote is specifically from p. 143.)

In the International Journal of Modern Anthropology, H. Chaabani writes the following. "In fact the general idea of biological evolution was advanced more than 1,000 years before Darwin by the Iraqi thinker and writer Amr ibn Bahr Al Jahis (800-868) in his famous work presented in his book "Book of Animals", in which he was the first to discuss food chains, and was an early adherent of environmental determinism, arguing that the environment can determine the physical characteristics of the inhabitants and that the origins of different human skin colours is the result of the environment. He was also the first to describe the struggle for existence and an early theory of evolution by natural selection and considered the father of evolutionary theory." (H. Chaabani, "Insights on the history of Anthropology: its emergence in the wider Middle East before it existed as a discipline", International Journal of Modern Anthropology, 5: 80 (2012) - this quote is specifically from p. 84.)

Why the "knee-jerk" reaction and deletion, without any reason given, against the idea of that there were Arab scholars who wrote on related ideas? Why can we accept a Greek and Roman contribution, but then cannot apparently accept that the Arabs wrote on related topics too - despite the scholarly evidence, published in academic journals?

Fariduddien - March 11, 2013.

But do any of these citations actually describe evolution? The Greek and Roman contributions we mention describe humans descending from non human ancestors for example, and that is clearly evolution. The idea that people in hot countries are blacker, is extremely ancient, for example found in Herodotus, but not an explanation of evolution.--Andrew Lancaster (talk) 20:06, 11 March 2013 (UTC)[reply]

My concern here is a potential WP:SYNTH issue. Dbrodbeck (talk) 20:52, 11 March 2013 (UTC)[reply]

My sentence only had two components, that of Al-Jahiz mentioning food chains, and mentioning the struggle for existence. It would seem to me that your concern could be allayed by simply having separate references for each concept, rather than putting all the references at the end of the sentence as I did. Would that be correct? - Fariduddien, 11 March 2013

The struggle for existence is clearly an important component of Darwin's theory of evolution, and thus I believe Al-Jahiz is relevant.

I don't think anyone expects anyone prior to Darwin to have a fully-fledged theory of evolution - certainly the Greeks and Romans did not.

My first edit which was deleted also included a brief mention of the writings of Ibn Khaldun (14th century), which includes something closer to what you are asking about (though admittedly I did not provide scholarly references in my initial edit).

Here is a quotation from the Muqaddimah of Ibn Khaldun.

"It should be known that we - May God guide you and us - notice that this world with all the created things in it has a certain order and solid construction. It shows nexuses between causes and things caused, combinations of some parts of creation with others, and transformations of some existent things into others, in a pattern that is both remarkable and endless. [...]

"One should then look at the world of creation. It started out from the minerals and progressed, in an ingenious, gradual manner, to plants and animals. The last stage of minerals is connected with the first stage of plants, such as herbs and seedless plants. The last stage of plants, such as palms and vines, is connected with the first stage of animals, such as snails and shellfish which have only the power of touch. The word 'connection' with regard to these created things means that the last stage of each group is fully prepared to become the first stage of the next group.

"The animal world then widens, its species become numerous, and, in a gradual process of creation, it finally leads to man, who is able to think and to reflect. The higher stage of man is reached from the world of the monkeys, in which both sagacity and perception are found, but which has not reached the stage of actual reflection and thinking. At this point we come to the first stage of man after (the world of monkeys). This is as far as our (physical) observation extends."

(From Ibn Khaldun (translated by F. Rosenthal), "The Muqaddimah: An Introduction to History, Volume 1" (Princeton University Press, 1967), pp. 194-195.)

One thing I find surprising and remarkable about this quote is that, after talking about "transformation" of lower plants to higher plants, and lower animals to higher animals, Ibn Khaldun proceeds to say, "The higher stage of man is reached from the world of the monkeys..."

Fariduddien - March 11, 2013

The struggle for existence was a common concept among those who believed in creation rather than evolution, in particular the Reverend Thomas Malthus who influenced Darwin directly. The quotes you describe indicate a form of sequential creation, which ain't evolution, so we need a really good secondary source for that extrapolation. . dave souza, talk 21:52, 11 March 2013 (UTC)[reply]

There seems to be a double standard here. Aristotle did not describe evolution either, yet he is somehow relevant. The reference for Titus Lucretius Carus appears to be a primary source, not a secondary source, yet somehow it seems if the contributor is European, these details can be overlooked. It sounds like the mentions of Aristotle and Titus Lucretius Carus should be deleted from the article, if you held these mentions to the same standards you are holding up mentions of Arab contributions.

Malthus is mentioned in the article, though you seem to be arguing against his inclusion. Should he be deleted too, if we are to have consistent standards? Note that Malthus came around 900 years after Al-Jahiz.

Regarding Ibn Khaldun, I am still in the process of researching the secondary sources at present (they exist, but of course, it's a matter of tracking down the relevant papers or books and ensuring accuracy). Fariduddien (talk) 22:10, 11 March 2013 (UTC)[reply]

Not a bad point. We could probably give less space to Aristotle and certainly to Plato. But the chief opponents and influences of very important figures like Darwin are obviously hard to avoid mentioning? Darwin was himself influenced by Aristotle, and Aristotle was the originator of some standard anti-evolution arguments which are important to the story. One of the unfortunate notability issues for the great Arab scientists is that their work became marginalized except in the cases where they became popular in Europe. But concerning biology I am not sure that Arab science and philosophy made anywhere near as much progress as it did in areas like maths and astronomy and medicine.--Andrew Lancaster (talk) 22:16, 11 March 2013 (UTC)[reply]

It sounds like I have to write an essay to get it included, but then it would be rejected for being too long. That's why I only wrote one sentence.

According to Bayrakdar (see reference above), Al-Jahiz's Book of Animals was not directly translated into European languages, but he was quoted or had his ideas repeated by other Arab scholars who were translated into European languages. Bayrakdar states the example of the Life of Animals of Al-Damiri, which he says contained many passages from Al-Jahiz's The Book of Animals and which was partially translated into Latin and published in 1617 (Darwin could read Latin). He mentions other examples as well. Fariduddien (talk) 22:54, 11 March 2013 (UTC)[reply]

Indeed, someone not only needs to write an essay showing the connection to Evolution (not just biology) but it also needs to get published somewhere. That is a basic requirement for something getting into Wikipedia.--Andrew Lancaster (talk) 10:45, 12 March 2013 (UTC)[reply]

Thanks Andrew, good point. Please see my comment on this further down the page. Fariduddien (talk) 23:59, 13 March 2013 (UTC)[reply]

<ec> The standard is high quality secondary sources covering the whole topic rather than promoting an agenda. As it happens, Aristotle is credited by CD with foreshadowing natural selection, but failing to fully comprehended the evolutionary principle. . . dave souza, talk 22:27, 11 March 2013 (UTC)[reply]

It sounds like you may be disparaging my sources. If there's something you don't like about any of the sources I have listed, please explicitly say why you are opposed to these sources. Four of my five listed sources are academic journals, three of which are science-related. The other source is a book on the history of biology published by a well-respected academic publisher (Springer). Fariduddien (talk) 23:01, 11 March 2013 (UTC)[reply]

There are industries promoting views that various cultures had various insights, however reliable secondary sources are required to show that material satisfies WP:DUE for an article like this. For an example of such an industry, see http://www.muslimheritage.com/, and for one example of a previous discussion see Talk:Evolution/Archive 54#Misuse of sources. Johnuniq (talk) 21:53, 11 March 2013 (UTC)[reply]

I have provided secondary sources for Al-Jahiz, and even provided extensive quotations here on this "Talk" page. Four of my references for Al-Jahiz are from scientific sources (three academic journals, and one book by a respected academic publisher, Springer). The other reference is from an Islam-related refereed academic journal, but I included it because it contains additional English translations from Al-Jahiz which I haven't found elsewhere (though I haven't quoted from it here as of yet, as that one seems to be the least conservative of my references). You are free to look any of these up independently, of course, if you don't trust my quotes. Many of them can be found online in some form (e.g. the Zirkle article is available for free on JSTOR if you register). I am still working on the secondary sources for Ibn Khaldun, which exist, but as I said elsewhere, it takes time to track papers and books down and to ensure accuracy. Fariduddien (talk) 22:22, 11 March 2013 (UTC)[reply]

But do any of the sources show evolution being proposed by Al-Jahiz? Please believe me, I am not just asking this question for no reason. It really is relevant, don't you think?--Andrew Lancaster (talk) 10:45, 12 March 2013 (UTC)[reply]

Thanks Andrew, I think your point (in this comment and in particular in your previous one) is a good one. I've taken a couple days to think about this further, and you're right - while the support is there to a degree in the academic literature (as shown by the sources I listed), it is probably at a stage where further work can be done. This doesn't seem to be an area of high priority for research for experts in the history of science (at least not as of yet), as they seem to prioritize other areas, though I think it is moving forward in small steps. There are also various claims by non-academics, but what I have read of their work usually leaves much to be desired from the viewpoint of objectivity (which is why I haven't referenced any of these websites and articles). Perhaps, as you seem to be suggesting, it is a matter for the research in this area to become better established.

I'll just mention that one of my motivations for this is that, as you may (or may not) know, it wasn't that long ago that it was de rigueur for anything in the history of science to jump from the ancient Greeks and possibly Romans straight to Roger Bacon and onwards. The assumption was that the Arabs, Persians, etc., had just "preserved" Greek knowledge without contributing anything to it. That view is becoming less and less common, as the Arab contribution is being more greatly recognized, including in such fundamental areas such as the scientific method (particularly the contribution of Ibn al-Haytham/Alhazen).

However, this article in its history section, seems to preserve this "jump" - straight from the Greeks to the European Middle Ages. From what I have seen in other fields, that usually suggests that the Arab contribution is being completely overlooked.

The evidence appears to be there that this is so. However, perhaps this is an area in which further research needs to be done (and published in scholarly journals). The evidence of precursors to Darwinian ideas certainly seem to be there (such as in the quotes from Al-Jahiz), and this is recognized in scholarly journals (as referenced above). The weakness in our present state of knowledge may perhaps be knowledge about the "chain of influence" from these Arab scholars (and others) to European scientists, or directly to Darwin himself. The only paper to explicitly address this in my references is the one by Bayrakdar, however, he has a good "plausibility argument" in his paper, but it could be further solidified. I'm sure further research will be done, and published, in future. I'll try to keep an eye on it, and possibly revisit this topic here at some point in the future! Fariduddien (talk) 23:25, 13 March 2013 (UTC)[reply]

Andrew Lancaster said, "But do any of the sources show evolution being proposed by Al-Jahiz?" In reply, I'll point out that Bayrakdar provides the following quote from Al-Jahiz in his paper.

"People said different things about the existence of al-miskh (= original form of quadrupeds). Some accepted its evolution and said that it gave existence to dog, wolf, fox and their similars. The members of this family came from this form (al-miskh)."

This certain sounds like evolution - the idea that an earlier quadruped prototype gave existence to different forms, such as dogs, wolves, foxes, etc.

However, having said that, I do think the state of history of science research could use some further advancing in this area, more specifically with researching the specific "chains of influence" from the Arab scholars to European ones. Fariduddien (talk) 23:51, 13 March 2013 (UTC)[reply]

Well it sounds like you see the point that "sounding like" evolution is not enough, because if that was enough then Wikipedia would be more full of people's personal thoughts on things. It will be interesting to see what scholarship comes up with in this area. Obviously accepting early medieval Arab influence in the development of many scientific fields is normal today. (I would say that the big gap in many stories now is the whole Roman period.)--Andrew Lancaster (talk) 07:56, 14 March 2013 (UTC)[reply]

Questions and Suggestion

Question 1: Do I add my bit to the top or the bottom? (Sorry if this is incorrect; I could not tell based on previous posts since there seemed no particular order.)

Question 2: Why when viewing the main page and clicking on the image (under "Part of a series on Evolutionary biology") do I not get a larger image instead of being redirected to some other page that does not contain the image? (i.e., How do I get to the large image so that I can actually see it?)

Suggestion: Improve the clarity of the image referred to in Question 2 above to include a separate link to the "redirect" page as well as a link to the image (or the page where the image can be found). Please make it clear to viewers how to get to where they want to go.

Thanks. Jdevola (talk) 01:29, 16 March 2013 (UTC)[reply]

1) Bottom :)

2) It looks like the image is part of the template: Template:Evolutionary_biology. It looks like there's a Template_talk:Evolutionary_biology#The_image_should_be_openable discussion at that talk page. I agree, it's very odd. TippyGoomba (talk) 01:39, 16 March 2013 (UTC)[reply]

A TED Talk by Stewart Brand, titled, "The dawn of de-extinction. Are you ready?" suggests another section should be added to this page, called De-Extinction.

See: http://www.youtube.com/watch?v=XKc9MJDeqj0

66.25.90.158 (talk) 11:05, 21 March 2013 (UTC) Edwin Earl Ross, edearl@satx.rr.com[reply]

^ C. Zirkle, "Natural Selection before the 'Origin of Species'", Proceedings of the American Philosophical Society, 84: 71 (1941).
^ M. Bayrakdar, "Al-Jahiz and the Rise of Biological Evolution", Islamic Quarterly, 21: 149 (1983).
^ F. N. Egerton, "A History of the Ecological Sciences, Part 6: Arabic Language Science—Origins and Zoological Writings", Bulletin of the Ecological Society of America, April 2002, p. 142.
^ P. S. Agutter and D. N. Wheatley, Thinking About Life: The History and Philosophy of Biology and Other Sciences, p. 42 (Springer, 2008).
^ H. Chaabani, "Insights on the history of Anthropology: its emergence in the wider Middle East before it existed as a discipline", International Journal of Modern Anthropology, 5: 80 (2012).

[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.

[OriginOfWhales-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.

[Hillis92-5] 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.

[Crandall94-6] 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!?

[crutch-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.

[19] C. Zirkle, "Natural Selection before the 'Origin of Species'", Proceedings of the American Philosophical Society, 84: 71 (1941).

[20] M. Bayrakdar, "Al-Jahiz and the Rise of Biological Evolution", Islamic Quarterly, 21: 149 (1983).

[21] F. N. Egerton, "A History of the Ecological Sciences, Part 6: Arabic Language Science—Origins and Zoological Writings", Bulletin of the Ecological Society of America, April 2002, p. 142.

[22] P. S. Agutter and D. N. Wheatley, Thinking About Life: The History and Philosophy of Biology and Other Sciences, p. 42 (Springer, 2008).

[23] H. Chaabani, "Insights on the history of Anthropology: its emergence in the wider Middle East before it existed as a discipline", International Journal of Modern Anthropology, 5: 80 (2012).

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]

[12]

[13]

[14]

[15]

[16]

[17]

[18]

[1]

[2]

[3]

[4]

[5]