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Objections to evolution have been raised since various evolutionary ideas came to be debated around the start of the nineteenth century.Johnston, Ian C. (1999). Section Three: The Origins of Evolutionary Theory. . . . And Still We Evolve. Liberal Studies Department, Malaspina University College. Retrieved on 2007-07-25. The ideas gained vast popular audiences, and when Charles Darwin brought out his 1859 book The Origin of Species he gradually convinced most of the scientific community that evolution was true. In the 1930s Darwin\'s theory of natural selection came to be seen as the primary explanation of the process of evolution.van Wyhe, John (2002-7). Charles Darwin: gentleman naturalist: A biographical sketch. The Complete Work of Charles Darwin Online. University of Cambridge. Retrieved on 2007-07-25. The existence of evolutionary processes, and the ideas of the modern evolutionary synthesis that explain them, although opposed by Young Earth Creationists, have since been uncontroversial among biologists.IAP STATEMENT ON THE TEACHING OF EVOLUTION, Interacademy Panel
Since then, nearly all criticisms of evolution have come from religious, rather than scientific, sources.In his comprehensive treatise on Creationism, The Creationists, historian Ronald Numbers traces the religious motivations, and often slim scientific pretensions, of prominent creationists from George Frederick Wright through George McCready Price, Harry Rimmer, John C. Whitcomb, Henry M. Morris and his Institute for Creation Research (and many lesser figures) to Phillip E. Johnson and the Intelligent design movement.
Numbers, Ronald (November 30, 2006). The Creationists: From Scientific Creationism to Intelligent Design, Expanded Edition. Harvard University Press, 624 pages. ISBN 0674023390. However, most Christians believe in God as Creator, while also accepting scientific evolution as a natural process.Godfrey, Laurie R. Scientists Confront Creationism. Pg 8. W. W. Norton & Company (1984). ISBN 0393301540. A minority of Christians rejected evolution from its outset as "heresy", but most attempted to reconcile scientific evolution with Biblical accounts of creation.D\'Souza, Dinesh. What\'s So Great about Christianity. Pg 144. Regnery Publishing (2007). ISBN 1596985178. Islam accepts the natural evolution of plants and animals, but the origin of man is contested and no consensus has emerged.Emerick, Yahiya. The Complete Idiot\'s Guide to Islam. Pg 81. Alpha Books (2001). ISBN 0028642333. The resultant creation-evolution controversy has been a recurring point of conflict between religion and science, most prevalent in certain, generally more conservative, regions of the United States.
In contrast to earlier objections to evolution that were either strictly scientific or explicitly religious, recent objections to evolution have frequently blurred the distinction. Movements such as Creation Science and Intelligent Design attack the scientific basis of evolution and argue that there is greater scientific evidence for the design of life by God or an intelligent being. Many of the arguments against evolution have become widespread, including objections to evolution\'s evidence, methodology, plausibility, morality, and scientific acceptance. However, these arguments are not accepted by the scientific community.Statement on the Teaching of Evolution. American Association for the Advancement of Science (2006). Retrieved on 2007-03-20.
Look up evolution in Wiktionary, the free dictionary.
One of the main sources of confusion and ambiguity in the creation-evolution debate is the definition of evolution itself. In the context of biology, evolution is simply the genetic change in populations of organisms over successive generations. However, the word has a number of different meanings in different fields, from evolutionary computation to chemical evolution to sociocultural evolution to stellar and galactic evolution. It can even refer to metaphysical evolution, spiritual evolution, or any of a number of evolutionist philosophies. When biological evolution is mistakenly conflated with other evolutionary processes, it can result in errors such as the claim that modern evolutionary theory says anything about abiogenesis or the Big Bang.Moran, Laurence (1993). What is Evolution?. The TalkOrigins Archive. Retrieved on 2007-03-24.
In colloquial contexts, evolution can refer to any sort of progressive development, and often bears a connotation of gradual improvement: evolution is understood as a process that results in greater quality or complexity. This common definition, when misapplied to biological evolution, leads to frequent misunderstandings. For example, the idea of devolution ("backwards" evolution) is a result of erroneously assuming that evolution is directional or has a specific goal in mind (cf. orthogenesis). In reality, the evolution of an organism does not entail objective improvement other than increasing "fitness" in its environment; and its suitability is only defined in relation to this environment. Biologists do not consider any one species, such as humans, to be more "highly evolved" or "advanced" than another.Ask the experts:Biology-Is the human race evolving or devolving?. Scientific American (1998). Retrieved on 2007-03-24.
Nor does evolution require that organisms become more complex. Although the history of life reflects a gradual trend towards a larger number of increasingly complex organisms, this is no more a necessary consequence of evolution than the existence of Mars is a necessary consequence of gravity; rather, it is a consequence of the specific circumstances of evolution on Earth, which frequently made greater complexity advantageous, and thus naturally selected for. Depending on the situation, organisms\' complexity can either increase, decrease, or stay the same, and all three of these trends have been observed in biological evolution; indeed, decreasing complexity is exceedingly common.
Creationist sources frequently define evolution according to its colloquial, rather than scientific, meaning. As a result, many attempts to rebut evolution are actually straw men that do not address the claims of evolutionary biology. This also means that advocates of creationism and evolution often simply speak at odds with each other.Doolan, Robert (1996). Oh! My aching wisdom teeth!. Answers in Genesis. Retrieved on 2007-03-24.
Even as it gained increasing scientific acceptance, Darwin\'s theory of evolution met strong religious resistance.
The earliest objections to Darwinian evolution were both scientific and religious. Although most of Darwin\'s contemporaries came to accept the transmutation of species based upon fossil evidence,[citation needed] the specific evolutionary mechanism which Darwin provided, natural selection, was actively disputed by alternative theories such as Lamarckism and orthogenesis. Darwin\'s gradualistic account was also opposed by saltationism and catastrophism. Additionally, the specific hereditary mechanism Darwin provided, pangenesis, lacked any supporting evidence. In the early 20th century, pangenesis was replaced by Mendelian inheritance, leading to the rise of the modern evolutionary synthesis. Darwinism, in its revised form as "Neo-Darwinism", rose to universal acceptance among biologists with the help of new evidence, such as genetics, which confirmed Darwin\'s predictions and refuted the competing theories.Bowler, PJ (2003). Evolution: The History of an Idea, Third Edition, Completely Revised and Expanded. University of California Press. ISBN 978-0520236936.
Since then, although disagreements and new ideas have continued over certain specific points, such as punctuated equilibrium, evolutionary theory itself has been entirely uncontested in the field of biology, and indeed is commonly described as the "cornerstone of modern biology".Overton, William (1982). McLean v. Arkansas Board of Education. The TalkOrigins Archive. Retrieved on 2007-03-24.Colby, C (1996). Introduction to Evolutionary Biology. The TalkOrigins Archive. Retrieved on 2007-03-24.
Many early religious objections to Darwin\'s theory, in contrast, continue to thrive to this day. The idea that species had developed over time by natural processes from a common ancestor seemed to contradict the Genesis account of Creation. Many believers in Biblical infallibility thus attacked Darwinism as heretical. The most common early religious arguments against evolution were Paley\'s watchmaker analogy, an argument from design still heavily utilized by the modern creationist movement. The idea of organs developing incrementally was also objected to, in the form of questions like "what use is half a wing?" or "what use is half an eye?" This, however, is a \'straw man\' argument: evolution does not postulate half an eye, but an eye that is half as efficient. The incremental improvement refers to an organ\'s ability, rather than its structure.
In the 20th century, the wide acceptance of evolution by the scientific community led to frequent conflicts between creationism and evolution, comprising the creation-evolution controversy. Most of these conflicts have centered on the objections of Christian fundamentalists in the United States to the teaching of evolution in public schools. Although early objections simply dismissed evolution for seeming to contradict the Bible, this argument was invalidated when the Supreme Court ruled in Epperson v. Arkansas that forbidding the teaching of evolution on religious grounds violated the Establishment Clause.
Since then, many creationists have developed more sophisticated objections to evolution, alleging that it is unscientific, that its teaching infringes on creationists\' religious freedoms, that belief in evolution is religious, or that belief in God is scientific. Creationists have appealed to democratic principles of fairness, arguing that evolution is controversial, and that science classrooms should therefore "Teach the Controversy" and let students decide what to believe for themselves. These objections to evolution culminated in the intelligent design movement in the 1990s, which has gained significant public support in the United States.National Science Teachers Association Disappointed About Intelligent Design Comments Made by President Bush. National Science Teachers Association Press (2005). Retrieved on 2007-03-24.
Many recent objections to evolutionary theory have focused on downplaying its scientific acceptance, attempting to discredit or invalidate it in order to advocate creationism as an equally good, or superior, explanation for life\'s diversity. Creationists often argue, for example, that evolution is unproven, non-factual, or controversial.
Critics of evolution frequently assert that evolution is "just a theory", with the intent of emphasizing evolution\'s unproven nature, or of characterizing it as a matter of opinion rather than of fact or evidence. This reflects a misunderstanding of the meaning of theory in a scientific context: whereas in colloquial speech a theory is a conjecture or guess, in science a theory is simply an explanation or model of the world that makes testable predictions. When evolution is used to describe a theory, it refers to an explanation for the diversity of species and their ancestry. An example of evolution as theory is the modern synthesis of Darwinian natural selection and Mendelian inheritance. As with any scientific theory, the modern synthesis is constantly debated, tested, and refined by scientists. There is an overwhelming consensus in the scientific community that it remains the only robust model that accounts for the known facts concerning evolution.Moran, Laurence (1993). Evolution is a Fact and a Theory. The TalkOrigins Archive. Retrieved on 2007-03-24.
Critics also state that evolution is not a fact. In science, a fact is a verified empirical observation; in colloquial contexts, however, a fact can simply refer to anything for which there is overwhelming evidence. For example, in common usage theories such as "the Earth revolves around the Sun" and "objects fall due to gravity" may be referred to as "facts", even though they are purely theoretical. From a scientific standpoint, therefore, the theory of evolution may be called a "fact" for the same reason that gravity can: under the technical definition, this applies to the observed process of evolution occurring whenever a population of organisms genetically changes over time, whereas under the colloquial definition, this applies to evolutionary theory\'s well-established nature. Thus, evolution is widely considered both a theory and a fact by scientists.Isaak, Mark (2003). Five Major Misconceptions about Evolution. The TalkOrigins Archive. Retrieved on 2007-03-24.Gould, SJ (1994). Hen\'s Teeth and Horse\'s Toes. W. W. Norton & Company, 253-262. ISBN 0393017168. Retrieved on 2007-03-24. Lenski, RE (2000). Evolution: Fact and Theory. ActionBioscience.org. Retrieved on 2007-03-24.
Similar confusion is involved in objections that evolution is "unproven";Morris, HM (1985). Scientific Creationism. Master Books. ISBN 978-0890510025. strict proof is possible only in logic and mathematics, not science, so this is trivially true, and no more an indictment of evolution than calling it a "theory" is. The confusion arises, however, in that the colloquial meaning of proof is simply "compelling evidence", in which case scientists would indeed consider evolution "proven". The distinction is an important one in philosophy of science, as it relates to the lack of absolute certainty in all empirical claims, not just evolution.Theobald, Douglas (2004). 29+ Evidences for Macroevolution: Scientific "Proof", scientific evidence, and the scientific method. The TalkOrigins Archive. Retrieved on 2007-03-24.
One of the most recent major objections to evolution is in a sense self-fulfilling: it argues that evolution is controversial or contentious. Unlike past creationist arguments which sought to abolish the teaching of evolution altogether, this argument makes the weaker claim that evolution, being controversial, should be provided alongside other, alternative views, and students should be allowed to evaluate and choose between the options on their own.Meyer, SC. "Teach the controversy", Cincinnati Enquirer, 2002. Retrieved on 2007-03-24. This appeal to "fairness" and a more democratic, "balanced" approach in which conflicting views are given "equal time" appeals to many American creationists, and has been endorsed by President George W. Bush.Isaak, M (2004). Index to Creationist Claims, Claim CA040: Equal time. The TalkOrigins Archive. Retrieved on 2007-03-24.
This objection forms the basis of the "Teach the Controversy" campaign, an attempt by the Discovery Institute to promote the teaching of intelligent design in public schools. This in turn forms a major part of the Institute\'s "wedge strategy", an attempt to gradually undermine evolution and ultimately to "reverse the stifling materialist world view and replace it with a science consonant with Christian and theistic convictions".A copy of the Discovery Institutes Wedge Strategy document can be found here: Wedge Strategy. Discovery Institute (1999). Retrieved on 2007-03-24.
Scientists and U.S. courts have rejected this objection on the grounds that science is not based on appeals to popularity, but on evidence. The scientific consensus of biologists, not popular opinion or "fairness", determines what is considered acceptable science, and it is argued that although evolution is clearly controversial in the public arena, it is entirely uncontroversial among experts in the field.
In response, creationists have disputed the level of scientific support for evolution. The Discovery Institute has gathered over 600 scientists since 2001 to sign "A Scientific Dissent From Darwinism" in order to show that there are a number of scientists who dispute Darwinian evolution. This statement did not profess outright disbelief in Darwinian evolution, but expressed skepticism as to the ability of "random mutation and natural selection to account for the complexity of life." Several counter-petitions have been launched in turn, including A Scientific Support for Darwinism, which gathered over 7,000 signatures in four days, and Project Steve, a tongue-in-cheek petition that has gathered 864 (as of January 28, 2008) evolution-supporting scientists named "Steve".
Creationists have argued for over a century that evolution is "a theory in crisis" that will soon be overturned. This is based on a variety of objections to evolution, including that it lacks reliable evidence or violates natural laws. These objections have been rejected by most scientists, as have claims that intelligent design, or any other creationist explanation, meets the basic scientific standards that would be required to make them scientific "alternatives" to evolution. It is also argued that even if evidence against evolution exists, it is a false dilemma to characterize this as evidence for intelligent design.Morton, GR (2002). The Imminent Demise of Evolution: The Longest Running Falsehood in Creationism. Retrieved on 2007-03-24.
A similar objection to evolution is that certain scientific authorities — mainly pre-modern ones — have doubted or rejected evolution. Most commonly, it is argued that Darwin "recanted" on his deathbed, a myth originating from the Lady Hope Story. These objections are generally rejected as appeals to authority. Even if this myth were true, it would hold no bearing on the merit of the theory itself.
A common neocreationist objection to evolution is that evolution does not adhere to normal scientific standards — that it isn\'t genuinely scientific. It is argued that evolution does not follow the scientific method, and therefore should not be taught in science classes, or at least should be taught alongside other views (i.e., creationism). These objections often deal with the very nature of Darwinian evolution and the scientific method.
Creationists commonly argue against evolution on the grounds that "evolution is a religion; it is not a science".Ham, K (1987). The Lie: Evolution. Master Books. ISBN 0-89051-158-6. Retrieved on 2007-03-24. see Evolution is Religion, Chapter 2 The purpose of this criticism is to undermine the "higher ground" biologists claim in debating creationists, and to reframe the debate from being between science (evolution) and religion (creationism) to being between two equally religious beliefs — or, in some cases, even to argue that evolution is religious, while some form of creationism (typically intelligent design) is not.Dembski, WA (2006). The Design Inference: Eliminating Chance through Small Probabilities (Cambridge Studies in Probability, Induction and Decision Theory). Cambridge University Press. ISBN 978-0521678674. Morris, HM (2001). "Evolution Is Religion—Not Science". Impact: Vital Articles on Science/Creation 332. Those that oppose evolution frequently refer to supporters of evolution as "Evolutionists" or "Darwinists".
The arguments for evolution being a religion generally amount to arguments by analogy: it is argued that evolution and religion have one or more things in common, and that therefore evolution is a religion. Examples of alleged similarities include claims that evolution is based on faith, that supporters of evolution revere Darwin as a prophet, and that supporters of evolution dogmatically reject alternative suggestions out-of-hand.Wiker, BD (2003). Does Science Point to God? Part II: The Christian Critics. Crisis Magazine. Retrieved on 2007-03-25. These claims have become more popular in recent years as the neocreationist movement has sought to distance itself from religion, thus giving it more reason to make use of a seemingly anti-religious analogy.Scott, EC (2004). Evolution vs. Creationism: An Introduction. University of California Press. ISBN 0520246500.
In response, supporters of evolution have argued that no scientist\'s claims, including Darwin\'s, are treated as sacrosanct, as shown by the aspects of Darwinism that have been rejected or revised by scientists over the years, forming "Neo-Darwinism".Isaak, Mark (2004). "Index to Creationist Claims, Claim CA611: Evolution Sacrosanct?". TalkOrigins Archive. The claim that evolution relies on faith, often based on the idea that evolution has never been observed, is likewise rejected on the grounds that evolution has strong supporting evidence, and therefore does not require faith.
In general, the argument that evolution is religious has been rejected on the grounds that religion is not defined by how dogmatic, closed-minded, or zealous its adherents are, but by its spiritual or supernatural beliefs. In addition to disputing the idea that evolution is dogmatic or based on faith, thus, supporters of evolution accuse creationists of equivocating between the strict definition of religion and its colloquial usage to refer to anything that is enthusiastically or dogmatically engaged in. U.S. courts have also rejected this objection:
Assuming for the purposes of argument, however, that evolution is a religion or religious tenet, the remedy is to stop the teaching of evolution, not establish another religion in opposition to it. Yet it is clearly established in the case law, and perhaps also in common sense, that evolution is not a religion and that teaching evolution does not violate the Establishment Clause.McLean v Arkansas Board of Education, 529 F.Supp. 1255 (US District Court 1982).
A related claim is that evolution is atheistic; creationists sometimes merge the two claims and describe evolution as an "atheistic religion" (cf. humanism). This argument against evolution is also frequently generalized into a criticism of all science; it is argued that "science is an atheistic religion", on the grounds that its methodological naturalism is as unproven, and thus as "faith-based", as the supernatural and theistic beliefs of creationism.Cline, A (2006). Myth: Science is a Religion for Atheists that Requires Faith. about.com. Retrieved on 2007-03-25.
A statement is considered falsifiable if there is an observation or a test that could be made that would demonstrate that the statement is false. Evolution is considered falsifiable because it makes many predictions which, if they were contradicted by the evidence, would falsify evolution. In contrast, many religious beliefs are not falsifiable, because no testable prediction has been made about the supernatural.Wilkins, JS (1997). Evolution and Philosophy:Is Evolution Science, and What Does \'Science\' Mean?. The TalkOrigins Archive. Retrieved on 2007-03-25.
Many creationists (for example Henry M. MorrisScientific Creationism, Henry M. Morris, 1974 Master Books, Arkansas, pp. 6-7) have claimed that evolution is unfalsifiable. They claim that any fact can be fit into the evolutionary framework, and that therefore it is impossible to demonstrate evolution is wrong.TalkOrigins Claim CA211, Mark Isaak, editor, Index to Creationist Claims, TalkOrigins, Copyright © 2006 Evolution is not in fact unfalsifiable, but it may appear to be so because it is so widely confirmed, and so foundational, that the likelihood of any evidence disproving it wholesale (as opposed to merely refining it) has become increasingly improbable and difficult to the point of virtual impossibility - as is the case with theories such as gravitation.
Others claim that past events of speciation are not observable and repeatable, and therefore evolution is not falsifiable. In 1976, Popper himself said that "Darwinism is not a testable scientific theory but a metaphysical research programme".Popper, K (1985). Unended Quest: An Intellectual Autobiography. Open Court. ISBN 978-0087583436. However, Popper later recanted, and offered a more nuanced view of its status:
However, Darwin\'s own most important contribution to the theory of evolution, his theory of natural selection, is difficult to test. There are some tests, even some experimental tests; and in some cases, such as the famous phenomenon known as \'industrial melanism\', we can observe natural selection happening under our very eyes, as it were. Nevertheless, really severe tests of the theory of natural selection are hard to come by, much more so than tests of otherwise comparable theories in physics or chemistry.Popper, K (1978). "Natural selection and the emergence of mind". Dialectica (32). Misquoted Scientists Respond by John R. Cole quoting Popper: "I have changed my mind about the testability and logical status of the theory of natural selection, and I am glad to have the opportunity to make a recantation."
In response to this criticism of evolution, numerous examples of potential ways to falsify evolution have been proposed. J.B.S. Haldane, when asked what hypothetical evidence could disprove evolution, replied "fossil rabbits in the Precambrian era"Ridley, M (2003). Evolution, Third Edition. Blackwell Publishing Limited. ISBN 978-1405103459. (more recently, Richard Dawkins has made a similar observation).Wallis, C. "The Evolution Wars", Time Magazine, 2005, pp. 32. Retrieved on 2007-03-24. Dawkins, Richard (1995). River Out of Eden. Basic Books. ISBN 0-465-06990-8. Dawkins, Richard (1986). The Blind Watchmaker. W. W. Norton & Company, Inc.. ISBN 0-393-31570-3. Numerous other potential ways to falsify evolution have also been proposed.
A related claim, also once used, but then abandoned, by Popper, is that natural selection is tautological. Specifically, it is often argued that the phrase "survival of the fittest" is a tautology, in that fitness is defined as ability to survive and reproduce. However, this phrase was first used by Herbert Spencer in 1864, and has rarely been used by biologists since. Additionally, fitness is more accurately defined as the state of possessing traits that make survival more likely; this definition, unlike simple "survivability", avoids being trivially true.Wilkins, JS (1997). Evolution and Philosophy: A Good Tautology is Hard to Find. The TalkOrigins Archive. Retrieved on 2007-03-24.Arguments we think creationists should NOT use. Answers in Genesis (2006). Retrieved on 2007-03-24.See Survival of the fittest for a more thorough discussion.
Similarly, it is argued that evolutionary theory is circular reasoning, in that evidence is interpreted as supporting evolution, but evolution is required to interpret the evidence. An example of this is the claim that geological strata are dated through the fossils they hold, but that fossils are in turn dated by the strata they are in. However, in most cases strata are not dated by their fossils, but by their position relative to other strata and by radiometric dating, and many strata were dated before the theory of evolution was formulated.MacRae, A (1998). Radiometric dating and the geological time scale: Circular reasoning or reliable tools. The TalkOrigins Archive. Retrieved on 2007-03-24.
In his book, Abusing Science: The Case Against Creationism, philosopher of science Philip Kitcher specifically addresses the "falsifiability" question by taking into account notable philosophical critiques of Popper by Carl Gustav Hempel and Willard Van Orman Quine that reject his definition of theory as a set of falsifiable statements is wrong Hempel. C.G. 1951 “Problems and Changes in the Empiricist Criterion of Meaning” in Aspects of Scientific Explanation. Glencoe: the Free Press. Quine, W.V.O 1952 “Two Dogmas of Empiricism” reprinted in From a Logical Point of View. Cambridge: Harvard University Press . As Kitcher points out, if one took a strictly Popperian view of “theory,” observations of Uranus when first discovered in 1781 would have “falsified” Newton’s celestial mechanics. Rather, people suggested that another planet influenced Uranus’ orbit – and this prediction was indeed eventually confirmed. Kitcher agrees with Popper that “there is surely something right in the idea that a science can succeed only if it can fail” Philip Kutcher 1982 Abusing Science: The Case Against Creationism. Page 45 Cambridge: The MIT Press. But he insists that we view scientific theories as consisting of an “elaborate collection of statements,” some of which are not falsifiable, and others – what he calls “auxiliary hypotheses,” which are.
According to Kitcher, good scientific theories must have three features: (1) unity: “A science should be unified …. Good theories consist of just one problem-solving strategy, or a small family of problem-solving strategies, that can be applied to a wide range of problems” (1982: 47). (2) Fecundity: “A great scientific theory, like Newton’s, opens up new areas of research. …. Because a theory presents a new way of looking at the world, it can lead us to ask new questions, and so to embark on new and fruitful lines of inquiry …. Typically, a flourishing science is incomplete. At any time, it raised more questions than it can currently answer. But incompleteness is now vice. On the contrary, incompleteness is the mother of fecundity …. A good theory should be productive; it should raise new questions and presume that those questions can be answered without giving up its problem-solving strategies” (1982: 47-48). (3) auxiliary hypothesis that are independently testable: “An auxiliary hypothesis ought to be testable independently of the particular problem it is introduced to solve, independently of the theory it is designed to save” (1982: 46) (e.g. the evidence for the existence of Neptune is independent of the anomalies in Uranus’s orbit).
Like other definitions of theories, including Popper’s, Kitcher makes it clear that a good theory includes statements that have (in his terms) “observational consequences.” But, like the observation of irregularities in Uranus’s orbit, falsification is only one possible consequence of an observation. The production of new hypotheses is another possible – and equally important – observational consequence. Kitcher’s account of a good theory of course is based not only on his understanding of how physical sciences work. He is also taking into account the way the life sciences work.
From Kitcher’s point of view, Darwinian theory not only meets the three conditions for a good scientific theory; it is without question an extraordinarily successful theory:
Objections to evolution\'s evidence tend to be more concrete and specific, often involving direct analysis of evolutionary biology\'s methods and claims.
Transitional species such as the Archaeopteryx have been a fixture of the creation-evolution debate for almost 150 years.
A common claim of creationists is that evolution has never been observed.Kent Hovind. The Dangers of Evolution [DVD]. USA: Creation Science Evangelism. Challenges to such objections often come down to debates over how evolution is defined. Under the conventional biological definition of evolution, it is a simple matter to observe evolution occurring. Evolutionary processes, in the form of populations changing their genetic composition from generation to generation, have been observed in many different scientific contexts, including the evolution of fruit flies and bacteria in laboratory settings, and of tilapia in the field.
In response to such examples, many creationists specify that they are objecting only to macroevolution, not microevolution:Questions frequently asked about the TBSEF, Texans for Better Science Education FoundationKansas Evolution Hearings Part 10, Kansas evolution hearings most creationist organizations do not dispute the occurrence of short-term, relatively minor evolutionary changes, such as that observed even in dog breeding. Rather, they dispute the occurrence of major evolutionary changes over long periods of time, which by definition cannot be directly observed, only inferred from microevolutionary processes and the traces of macroevolutionary ones.
However, as biologists define macroevolution, both microevolution and macroevolution have been observed. Speciations, for example, have been directly observed many times, despite popular misconceptions to the contrary.Boxhorn, Joseph (1995). Observed Instances of Speciation. The TalkOrigins Archive. Retrieved on 2007-03-24. Additionally, modern evolutionary synthesis draws little distinction between macroevolution and microevolution, considering the former to simply be the latter on a larger scale.Wilkins, J (2006). Macroevolution: Its Definition, Philosophy and History. The TalkOrigins Archive. Retrieved on 2007-03-24.
Additionally, past macroevolution can be inferred from historical traces. Transitional fossils, for example, provide plausible links between several different groups of organisms, such as Archaeopteryx linking birds and dinosaurs, or the recently-discovered Tiktaalik linking fish and amphibians. Creationists dispute such examples in a variety of ways, from asserting that such fossils are hoaxes or that they belong exclusively to one group or the other, to asserting that there should be far more evidence of obvious transitional species.Hunt (1997). Transitional Vertebrate Fossils FAQ. The TalkOrigins Archive. Retrieved on 2007-03-24. Darwin himself found the paucity of transitional species to be one of the greatest weaknesses of his theory: "Why is not every geological formation and every stratum full of such intermediate links? Geology assuredly does not reveal any such finely graduated organic chain, and this perhaps is the greatest objection which can be urged against my theory."Darwin, C (1859). The Origin of Species. John Murray. However, the number of clear transitional fossils has increased enormously since Darwin\'s day, and this problem has been largely resolved with the advent of the theory of punctuated equilibrium, which predicts a primarily stable fossil record broken up by occasional major speciations.Elsberry, WR (1998). Missing links still missing!. The TalkOrigins Archive. Retrieved on 2007-03-24.
Creationists counter that even observed speciations and transitional fossils are insufficient evidence for the vast changes summarized by such phrases as "fish to philosophers" or "particles to people".A faithful man takes on faith-based teaching. Answers in Genesis. Retrieved on 2007-03-24. As more and more compelling direct evidence for inter-species and species-to-species evolution has been gathered, creationists have redefined their understanding of what amounts to a "created kind", and have continued to insist that more dramatic demonstrations of evolution be experimentally produced.Wieland, C (1991). "Variation, information and the created kind". Journal of Creation 5 (1): 42-47. Retrieved on 2007-03-24. One version of this objection is "Were you there?", popularized by Ken Ham. It argues that because no one except God could directly observe events in the distant past, scientific claims are just speculation or "story-telling".Ham, Ken (1989). Were You There?. Institute for Creation Research. Retrieved on 2007-03-24.Isaak, M (2005). Index to Creationist Claims, Claim CA221: Were you there?. The TalkOrigins Archive. Retrieved on 2007-03-24.
In fields such as astrophysics or meteorology, where direct observation or laboratory experiments are difficult or impossible, the scientific method instead relies on observation and logical inference. In such fields, the test of falsifiability is satisfied when a theory is used to predict the results of new observations. When such observations contradict a theory\'s predictions, it may be revised or discarded if an alternative better explains the observed facts. For example, Newton\'s theory of gravitation was replaced by Einstein\'s theory of General Relativity when the latter was observed to more precisely predict the orbit of Mercury. Einstein, Albert (1916). "The Foundation of the General Theory of Relativity" (PDF). Annalen der Physik 49: 769-822. Retrieved on 2006-09-03.
Haeckel\'s embryo drawings are an example of debunked past evidence for evolution; many critics of evolution claim that modern demonstrations of evolution are similarly erroneous or fraudulent.
A related objection is that evolution is based on unreliable evidence. This objection goes further than the less substantial "evolution isn\'t proven" arguments, claiming that evolution isn\'t even well-evidenced. Typically, this is either based on the argument that evolution\'s evidence is full of frauds and hoaxes, that current evidence for evolution is likely to be overturned because some past evidence has been, or that certain types of evidence are inconsistent and dubious.
Arguments against evolution\'s reliability are thus often based on analyzing the history of evolutionary thought or the history of science in general. Creationists point out that in the past, major scientific revolutions have overturned theories that were at the time considered near-certain. They thus claim that current evolutionary theory is likely to undergo such a revolution in the future, on the basis that it is a "theory in crisis" for one reason or another.Isaak, M (2004). Index to Creationist Claims, Claim CA110: Evolution will soon be widely rejected.. The TalkOrigins Archive. Retrieved on 2007-03-24.
Critics of evolution commonly appeal to past scientific hoaxes such as the Piltdown Man forgery. It is argued that because scientists have been mistaken and deceived in the past about evidence for various aspects of evolution, some or all of the current evidence for evolution is likely to also be based on fraud and error. Much of the evidence for evolution has been accused of being fraudulent at various times, including Archaeopteryx, peppered moth melanism, and Darwin\'s finches; these claims have been subsequently refuted.Nedin, C (1997). On Archaeopteryx, Astronomers, and Forgery. The TalkOrigins Archive. Retrieved on 2007-03-24.Wells, J (2002). Icons of Evolution. Regnery Publishing, Inc.. ISBN 978-0895262004. Icons of Evolution FAQs. The TalkOrigins Archive (2006). Retrieved on 2007-03-24.
It has also been claimed that certain former pieces of evidence for evolution which are now considered out-of-date and erroneous, such as Ernst Haeckel\'s 19th-century embryo drawings, were not merely errors but frauds; biology textbooks have drawn significant criticism from both opponents and supporters of evolution for continuing to reproduce such evidence after it has been debunked.
Creationists claim that evolution relies on certain types of evidence that do not give reliable information about the past. It is argued, for example, that radiometric dating, the technique of evaluating a material\'s age based on the radioactive decay rates of certain isotopes, generates inconsistent, and thus unreliable, results. Radiocarbon dating, based on the Carbon 14 isotope, has been particularly criticized. It is argued that radiometric decay relies on a number of unwarranted assumptions, such as the principle of uniformitarianism, consistent decay rates, or rocks acting as closed systems. This argument has been scientifically dismissed on the grounds that a variety of independent methods have confirmed the reliability of radiometric dating as a whole; additionally, different radiometric dating methods and techniques have independently confirmed each other\'s results.Isaak, M (2004). Index to Creationist Claims, Claim CD010: Radiometric Dating. The TalkOrigins Archive. Retrieved on 2007-03-24.
Another form of this objection is that fossil evidence is not reliable. This is based on a much wider range of claims. These include that there are too many "gaps" in the fossil record, that fossil-dating is cyclic (see evolution is unfalsifiable), or that certain fossils, such as polystrate fossils, are seemingly "out of place". It is argued that certain features of evolution support creationism\'s catastrophism (cf. Great Flood), rather than evolution\'s gradualistic punctuated equilibrium.Isaak, M (2004). Index to Creationist Claims, Claim CC363: Requirements for fossilization. The TalkOrigins Archive. Retrieved on 2007-03-24.
Some of the oldest and most common objections to evolution dispute whether evolution can truly account for all the apparent complexity and order in the natural world. It is argued that evolution is too unlikely or otherwise lacking to account for various aspects of life, and therefore that an intelligence—God—must at the very least be appealed to for those specific features.
Because the theory of evolution is often thought of as the idea that life arose "by chance", design arguments such as William Paley\'s watchmaker analogy have been popular objections to the theory since Darwin\'s day.Wilkins, J (1997). Evolution and Chance. The TalkOrigins Archive. Retrieved on 2007-03-24.
An exceedingly prevalent objection to evolution is that it is simply too unlikely for life, in all its complexity and apparent "design", to have arisen "by chance". It is argued that the odds of life having arisen without a deliberate intelligence guiding it are so astronomically low that it is unreasonable to not infer an intelligent designer from the natural world, and specifically from the diversity of life.Battern, D (1995). Cheating with chance. Answers in Genesis. Retrieved on 2007-03-24. A more extreme version of this argument is that evolution cannot create complex structures. The idea that it is simply too implausible for life to have evolved on Earth is often encapsulated with a quotation that the "probability of life originating on earth is no greater than the chance that a hurricane sweeping through a scrap-yard would have the luck to assemble a Boeing 747" (a claim attributed to astrophysicist Fred Hoyle and known as Hoyle\'s fallacyLies, Damned Lies, Statistics, and Probability of Abiogenesis Calculations).
This view is thus invariably justified with arguments from analogy. The basic idea of this argument for a designer is the teleological argument, an argument for the existence of God based on the perceived order or purposefulness of the universe. A common way of using this as an objection to evolution is by appealing to the 18th-century philosopher William Paley\'s watchmaker analogy, which argues that certain natural phenomena are analogical to a watch (in that they are ordered, or complex, or purposeful), which means that, like a watch, they must have been designed by a "watchmaker" — an intelligent agent. This argument forms the core of intelligent design, a neocreationist movement seeking to establish certain variants of the design argument as legitimate science, rather than as philosophy or theology, and have them be taught alongside evolution.
This objection is fundamentally an argument by lack of imagination, or argument from incredulity: a certain explanation is seen as being counter-intuitive, and therefore an alternate, more intuitive explanation is appealed to instead. Supporters of evolution generally respond by arguing that evolution is not based on "chance", but on predictable chemical interactions: natural processes, rather than supernatural beings, are the "designer". Although the process involves some random elements, it is the non-random selection of survival-enhancing genes that drives evolution along an ordered trajectory. The fact that the results are ordered and seem "designed" is no more evidence for a supernatural intelligence than the apparent design of snowflakes is.News | The Hoya It is also argued that there is insufficient evidence to make statements about the plausibility or implausibility of abiogenesis, that certain structures demonstrate poor design, and that the implausibility of life evolving exactly as it did is no more evidence for an intelligence than the implausibility of a deck of cards being shuffled and dealt in a certain random order.
It has also been noted that arguments against some form of life arising "by chance" are really objections to nontheistic abiogenesis, not to evolution. Indeed, many arguments against "evolution" are based on the misconception that abiogenesis is a component of, or necessary precursor to, evolution. Similar objections sometimes conflate the Big Bang with evolution.
Christian apologist and philosopher Alvin Plantinga, a supporter of intelligent design, has formalized and revised the improbability argument as the evolutionary argument against naturalism, which asserts that it is irrational to reject a supernatural, intelligent creator because the apparent probability of certain faculties evolving is so low. Specifically, Plantinga claims that evolution cannot account for the rise of reliable reasoning faculties. Plantinga argues that whereas a God would be expected to create beings with reliable reasoning faculties, evolution would be just as likely to lead to unreliable ones, meaning that if evolution is true, it is irrational to trust whatever reasoning one relies on to conclude that it is true.Plantinga, A (1993). Warrant and Proper Function. Oxford University Press. ISBN 0-19-507864-0. This novel epistemological argument has been criticized similarly to other probabilistic design arguments. It has also been argued that rationality, if conducive to survival, is more likely to be selected for than irrationality, making the natural development of reliable cognitive faculties more likely than unreliable ones.Fitelson, B; Sober, E (1997). Plantinga\'s Probability Arguments Against Evolutionary Naturalism. Retrieved on 2007-03-24.Isaak, M (2005). Index to Creationist Claims, Claim CA120: Mind\'s fallibility. The TalkOrigins Archive. Retrieved on 2007-03-24.
It is frequently argued that a great weakness of evolutionary theory is that it does not, or cannot, explain a certain aspect of the natural world. Although there is broad agreement that certain aspects of life remain unexplained, some creationists go one step further and argue that evolution should be abandoned altogether because of the phenomena it doesn\'t explain. Many argue that an alternative explanation, such as intelligent design, can explain the things which evolution cannot. For example, Michael Behe has argued that current evolutionary theory can\'t account for certain complex structures, particularly in microbiology. On this basis, Behe argues that such structures were "purposely arranged by an intelligent agent" (see evolution is too implausible and argument from incredulity).Behe, MJ. "Darwin under the microscope", New York Times, 1996-10-29, p. 25. Retrieved on 2007-03-24.
In addition to complex structures and systems, among the many phenomena that critics variously claim evolution cannot explain are consciousness, free will, instincts, emotions, metamorphosis, photosynthesis, homosexuality, music, language, religion, morality, and altruism (see altruism in animals).Johnson, P (1990). Evolution as dogma: The establishment of naturalism. Retrieved on 2007-03-24. Some of these have, in fact, been well-explained by evolution, while others remain largely mysterious, or only have preliminary explanations. However, supporters of evolution contend that no alternative explanation has been able to adequately explain the biological origin of these phenomena either.
In some cases, creationists argue against evolution on the grounds that it can\'t explain certain non-evolutionary processes, such as abiogenesis, the Big Bang, or the meaning of life. In such instances, evolution is being redefined to refer to the entire history of the universe, and it is argued that if one aspect of the universe is seemingly inexplicable, the entire body of scientific theories must be baseless. At this point, objections leave the arena of evolutionary biology and become general scientific or philosophical disputes.Isaak, M (2004). Index to Creationist Claims, Claim CE440: The origin of it all. theTalkOrigins Archive. Retrieved on 2007-03-24.
This class of objections is more radical than the above, claiming that some major aspect of evolution is not merely unscientific or implausible, but rather impossible, because it contradicts some other law of nature or is constrained in such a way that it cannot produce the biological diversity of the world.
An objection often made by creationists to evolutionary theory is that it allegedly can\'t account for the development of complex organs such as the eye.
Darwinian evolution posits that all biological systems must have developed incrementally from functional simpler systems. Every stage in the development of, for example, a fin into a leg, must have been sufficiently beneficial to be selected for. Both Darwin and his early detractors recognized the potential problems that could arise for evolutionary theory if the lineage of organs and other biological features could not be accounted for by such gradual, step-by-step changes over successive generations; if all the intermediary stages between an initial organ and the organ it will become are not all improvements upon the original, it will be impossible for the later organ to develop. Anticipating early criticisms that the evolution of the eye and other complex organs seemed impossible, Darwin noted that:
[R]eason tells me, that if numerous gradations from a perfect and complex eye to one very imperfect and simple, each grade being useful to its possessor, can be shown to exist; if further, the eye does vary ever so slightly, and the variations be inherited, which is certainly the case; and if any variation or modification in the organ be ever useful to an animal under changing conditions of life, then the difficulty of believing that a perfect and complex eye could be formed by natural selection, though insuperable by our imagination, can hardly be considered real.
Similarly, Richard Dawkins said on the topic of the evolution of the feather in an interview for the television program The Atheism Tapes:
There\'s got to be a series of advantages all the way in the feather. If you can\'t think of one, then that\'s your problem not natural selection\'s problem... It\'s perfectly possible feathers began as fluffy extensions of reptilian scales to act as insulators... The earliest feathers might have been a different approach to hairiness among reptiles keeping warm.
Despite creationist arguments such as "What use is half an eye?" and "What use is half a wing?", subsequent research has confirmed that the natural evolution of such organs is entirely feasible.Gehring, W.J. (2005). "New Perspectives on Eye Development and the Evolution of Eyes and Photoreceptors". Journal of Heredity 96 (3): 171-184. doi:10.1093/jhered/esi027. Eyes, Part One: Opening Up the Russian Doll. The Loom: A blog about life, past and future. Retrieved on 2007-09-22. Creationist claims have persisted that such complexity evolving without a designer is inconceivable, however, and this objection to evolution has been refined in recent years as the more sophisticated irreducible complexity argument of the intelligent design movement, formulated by biochemist Michael Behe.
Irreducible complexity is the idea that certain biological systems cannot be broken down into their consitutent parts and remain functional, and therefore that they could not have evolved naturally from less complex or complete systems. Whereas past arguments of this nature generally relied on macroscopic organ
