Talk:Evolution/FAQ

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This is a list of Frequently Asked Questions relevant to Wikipedia's Evolution article. This page was created in response to certain topics being brought up again and again on Talk:Evolution, wasting many editors' time and energy by forcing them to respond repeatedly to the same issues. The FAQ serves to address these common concerns, criticisms, and arguments by answering the various misconceptions behind them. 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.

Contents

[edit] Why won't you add criticisms or objections to evolution in the Evolution article?

Further information: Wikipedia:Neutral_point_of_view#Undue_weight

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, Evolution 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 creation-evolution controversy give major coverage to these opposing views, while biological articles such as evolution do not.

[edit] Evolution is controversial, so why won't you teach the controversy?

Further information: Teach the Controversy, Level of support for evolution

As noted above, evolution is at best only controversial in social areas like politics and religion. Evolutionary theory is not controversial in biology itself. 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 evolutionary theory as mainstream scientific consensus treats it: an uncontroversial, uncontested, enormously widely-accepted explanation with no scientifically supported "alternatives".

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, or the gene-centered view of evolution, are, in fact, covered extensively in Wikipedia's science articles. However, most are too minor or 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.

[edit] Why is evolution described as though it's a fact? Isn't evolution just a theory?

Further information: Evolution as theory and fact

That depends on what one means by evolution, by theory, and by fact. All of these words have at least two meanings. For example, evolution can either refer to an observed process (covered at evolution), or, as 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 gravity" is a theory. Gravity can thus either refer to a fact (the observation of objects being attracted to heavy objects) or a theory (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 modern evolutionary synthesis.

[edit] But isn't evolution unproven?

Main article: Evidence of evolution

Once again, this depends on how one is defining proof. Proof has two meanings: in logic and mathematics, it refers to a proposition that has been shown to be 100% certain and logically necessary; in other uses, it simply refers to a proposition that is well-supported (much like the colloquial meaning of fact).

In the former sense, evolutionary theory is not proven. However, this is trivially true, because nothing in natural sciences can be proven in the former sense: empirical claims such as those in science cannot ever be absolutely certain, because they always depend on unproven assumptions about the world around us. To call evolution "unproven" in this sense is true, but meaningless, because propositions like "the Earth revolves around the Sun" and even "the Earth exists" are equally unproven. 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.

In the latter 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.

[edit] Has evolution ever been observed?

Main article: Evidence of evolution

The process of evolution has been observed countless times in numerous situations. For example, both micro and macro evolution has been observed and tested in laboratories, particularly in organisms that breed rapidly, such as bacteria and fruit flies.[3] Evolution has also been observed in the field, such as in the fish tilapia, the plant Oenothera lamarckiana which gave rise to a new species of plant Oenothera gigas[4] and the peppered moth.[5] A new species of mosquito has evolved in the London Underground system since it opened.[6]

However, while the process of evolution has been observed many times, not every aspect of evolutionary theory, and particularly of the evolutionary history of life, has been directly observed. For example, non-avian dinosaurs have never been observed; their existence has only been inferred from their remains, in the form of fossils. However, these inferences are extremely well-supported by the mountains of evidence testifying to them. 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. In the same way, although the entire evolutionary history of life has not been directly observed, all available data supports the evolutionary model.

[edit] Why is microevolution equated with macroevolution?

Further information: Microevolution, Macroevolution

The article doesn't equate the two, but merely recognizes that they are largely or entirely the same process, just on different scales. 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 become large ("macro") ones, given enough time. Most of the topics covered in Evolution 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 that microevolution has been directly observed, while macroevolution has not. However, this is not the case, as speciations, which are generally seen as the benchmark for macroevolution, have been observed in a number of instances.

[edit] What about the scientific evidence against evolution?

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, Tiktaalik and Ambulocetus. That there are not more is explained by the rarity of fossilization and by punctuated equilibrium.[7][8]

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 source for the energy that fuels evolution, and most other reactions on the Earth, is the Sun. See also Entropy and life.[9][10]

3. Evolution can't create complex structures like the eye, or the bacterial flagellum.

The evolution of the eye and the evolution of flagella are well-understood, and irreducibly complex structures can arise through mechanisms such as exaptation, in which a structure is adapted to serve a different function. Moreover, the fact that the evolutionary history of every single biological structure in existence is not fully understood is not evidence against evolution, any more than the fact that the gravitational orbit of every astronomical body is not fully understood is evidence against gravity.[11][12]

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 new, random information is then processed by natural selection, which non-randomly favours beneficial variation. This turns the initially random information (created by mutations) into useful information that allows organisms to become better adapted. 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.[13][14]

More to the point, if there is any evidence against evolution, it is 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 Evolution 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.

[edit] How could life arise by chance?

If by "arise", one means "develop from non-organic matter through abiogenesis", then this is irrelevant to evolutionary theory. Abiogenesis is not an aspect of evolution, as 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 anymore than the fact that objects gravitate towards other objects is dependent upon the Big Bang. This is also an argument from ignorance.

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 distinctly non-random process. Mutation is random; natural selection is the very opposite of randomness. Natural selection occurs because organisms with beneficial characteristics survive and reproduce more than ones with harmful characteristics, and if these characteristics are heritable they will mechanically increase in frequency over generations. Although there are certain random aspects of evolution, such as genetic drift, this randomness is filtered through natural selection to lead to the non-random process of evolution.

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

[edit] See also

[edit] 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.

[edit] 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. ^ T. Dobzhansky, & O. Pavlovsky, "An experimentally created incipient species of Drosophilia", Nature 23, P. 289-292 (1971)
  4. ^ http://links.jstor.org/sici?sici=0006-8071(190909)48%3A3%3C179%3ATBOTCI%3E2.0.CO%3B2-Y
  5. ^ Franck et al, 1990; M. Losseau-Hoebeke, 1992
  6. ^ Byrne, Katharine & Nichols, Richard A., Heredity January 1999, Volume 82, Number 1, Pages 7-15
  7. ^ Hunt, Kathleen (1997). Transitional Vertebrate Fossils FAQ. TalkOrigins Archive.
  8. ^ Elsberry, Wesley R. (1998). Missing links still missing!?
  9. ^ Disorder — A Cracked Crutch For Supporting Entropy Discussions
  10. ^ Does Life On Earth Violate the Second Law of Thermodynamics?
  11. ^ Isaak, Mark (2005). Index to Creationist Claims, Claim CB200: Irreducible complexity. TalkOrigins Archive.
  12. ^ Robison, Keith (1996). Darwin's Black Box: Irreducible Complexity or Irreproducible Irreducibility?. TalkOrigins Archive.
  13. ^ Musgrave, Ian & Baldwin, Rich, et al (2005). Information Theory and Creationism. TalkOrigins Archive.
  14. ^ Evolution and Information: The Nylon Bug. New Mexicans for Science and Reason.