Defending Evolution from ID Distortions

Posts tagged “Atheist

Darwin’s Dilemma: My Take on the Discovery Institute’s Claims

I know it’s several months late, but I just got through watching a film done by the Discovery institute, on the Cambrian “explosion,” called “Darwin’s Dilemma: The Mystery of the Cambrian Explosion.” There are a few details that should be addressed about it. But, before I go into any kind of detail, yes, it should be pointed out that this is mostly the same kind of Creationist bull that I thought it would be, just a bit more sophisticated than the usual Creationist arguments made about the Cambrian radiation.

At first, typical of Creationist claims, Jonathan Wells makes the well-worn claim about life forms before and during the Cambrian. He compares the entire 3.8 to 4 billion years of life to a twenty-four hour day saying that for the first 21 hours, there were only unicellular life forms, and then the Cambrian life forms came into existence on the scale of a two minutes. This is an attempt to make the Cambrian radiation appear “sudden” A few minutes later, Wells then says something on the lines of that it could have happened over night which is complete bogus because it lasted at least 10 to 25 million years. Though there are higher estimates that go as high as 35 million years or more. The film says that fossil evidence shows that those estimates are too high, but it doesn’t give convincing details.

The film, however does mention the existence of other life forms, like the Ediacaran fauna which existed before the Cambrian, as well as fossil embryos. . . . Oh, about the fossil embryos, the film uses them to address the idea that pre-Cambrian fossils are not preserved because they were too soft. It is pointed out that these embryos were from soft-bodied organisms, and that they existed tens of millions of years before the Cambrian. From that, it is reasoned that if the appeal to pre-Cambrian organisms being too soft for preservation cannot be used. As the film argues this, the Discovery Institute seems to have missed a major implication of fossil embryos several millions of years before the Cambrian “explosion.” Think about it: Those embryos had to have come from precursor ancestors, and that would therefore show that the Darwinian prediction of the existence of simpler pre-Cambrian life. It shows, therefore, that such organisms did in fact exist, but that they were rarely ever fossilized. Fossilization is already a rare enough occurence without the organisms being much softer than is accustomed. But, another detail the DI seems to have missed: I do not remember any scientist ever saying that soft-bodied, pre-Cambrian fossils could never be preserved. They can be, it’s just much more of a novelty. Correct me if I am wrong, but I think the Discovery Institute is attacking a strawman.

Something I find exceptionally interesting is the interest that the film takes in fossils from southern China. All along, citing these fossils as evidence for their conclusion, I’m left to wonder why other fossils from China are ignored. In pre-Cambrian deposits dating from the Doushantou Formation, evidence of animal life in the form of adult Cnidirians was found. Among the finds were fossilized embryos and larvae tat resembled Anthrozoans. Not to mention, there s also evidence of cnidirian body plans with anthozoan affinity. An implication of this find is that  stem groups of bilaterians were also present between 25 to 45 million years before the Cambrian “explosion.” — Then, also there is more recent evidence from the same formation that complex, bilatarians existed between 40 to 55 million years before the Cambrian. — These fossil finds I cited were made in the first half of the last decade, between 2002, and 2005. These finds alone would show that the Cambrian “explosion” was likely less explosive. In contrast, the film Darwin’s Dilemma was released in September, 2009. Why didn’t the Discovery Institute include these fossil finds? Because of ignorance or bias? You make the call. — I go into more detail in my previous post entitled “The Truth on the Cambrian ‘explosion.’

Between scenes, the Discovery Institute indulges in the usual Creationist quote mining from well-known scientists about the appearance of the Cambrian fauna in the fossil record, but prominently Stephen Gould. Personally, I found that somewhat disrespectful since he is dead with his statements still being hijacked. Then also, they use a very selective quote from Richard Dawkins about the Cambrian’s abruptness in which he says, “It’s as though they were just planted there, without any evolutionary history.” You just have to realize that Dawkins is an Atheist and a major anti-Creationist to realize that he ultimately was not endorsing that view.  Besides, as he proposes a little later that “it might be that many of these animals had only soft parts to their bodies: no shells or bones to fossilize,” a view which the film goes out of its way to attempt refuting.  — The Quotes from Charles Darwin can be dismissed since they are 151 years out of date, and do not reflect the research accomplished since he published his theory.

A final claim made is on genetic information, and questioning whether or not Darwinian mechanisms can produce it. After deciding that it cannot, they resort to their typical “designer did it” cop-out. They try to rationalize their logic by saying that information is the product of intelligence, yada, yada . . . .  I’m not going to even bother to refute the typical argument from ignorance.

Basically, the film really doesn’t address anything that hasn’t been debunked before, it just seems to be a bit more sophisticated, and a bit more informative than other pieces of Creationist propaganda, but that’s probably because it admits to the existence of some fossils from before the Cambrian. I guess from that, it is the “best” Intelligent Design film I’ve ever seen, but that isn’t saying much. Mostly, the only real thing this film has going for it is its graphics, though I have seen better. I guess one of its goals is to dazzle the uninformed layperson with its computer graphics?  Who can tell? The Discovery Institute may accept the scientific age of the earth, but other than that, they aren’t much better than ICR.

References:
Precambrian Animal Life: Probable Developmental and Adult Cnidarian Forms from Southwest China, by Jun-Yuan Chena, Paola , Feng Gaoa, Stephen Q. Dornbos, Chia-Wei Lid, David J. Bottjer and Eric H. Davidson. From Science Direct, and Developmental Biology.
The Early Evolution of Animals by David J. Bottjer, from Scientific American.

Recommended Reading:
Transitional Forms and the Evolution of Phyla, by Glenn R. Morton, from American Scientific Affiliation. Published in Perspectives on Science and Christian Faith.
Cambrian Explosion, from SkepticWiki

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Evolution, Mutation and Misconceptions

A common objection to the Evolutionary model is the idea that Mutations are a driving force for change. It is seen all over Creationist literature that mutations destroy information, and never add anything, or have any benefits. — For example, the Muslim Creationist Harun Yahya claims,

The direct effect of mutations is harmful. The changes effected by mutations can only be like those experienced by people in Hiroshima, Nagasaki, and Chernobyl: that is, death, disability, and sickness. […] Not surprisingly, no useful mutation has been so far observed. All mutations have proved to be harmful. (The Evolution Deceit, page 55)

A few months ago, while I was debating with a creationist, I found myself having to correct a major misunderstanding he had. He repeated an argument  about Natural Selection, saying that Natural Selection is not the same as Evolution because it produces nothing new. It just “selects'” — As soon as he said this, I remembered hearing the same thing from a Kent Hovind debate. 

As soon as he said that, I quickly corrected him. Nobody says that Natural Selection “creates” anything new. When I took History of Life in Biology, that was one of the things I was taught: “Natural Selection doesn’t create new traits.” Mutations create new traits, and natural selection then determines if the new trait is favorable or good enough for a living organism to survive in a certain enviroment.  — He then interrupted saying, “Mutations are always harmful!” When I corrected him on that, he then said, “Well, cancer is a mutation! . . So, you’re telling me that if we get a whole population with cancer — “ At that, I kept repeating myself that wasn’t what I was saying and told him to stop attacking a strawman.

 He then defied me to name one beneficial mutation, just one. At that, I gave the (probably over cited) anti-bacterial resistance. He then said that didn’t count because the bacteria didn’t pass on the newly acquired resistence to its descendants, and the new traits have to be heritable. — But Creationists who make that claim are demonstrably wrong. The fact is that newly resistant bacteria do pass on their newly acquired resistance to new generations. I also pointed out the evolution of the HIV virus -the “ultimate evolver”- which didn’t seem to  make even the slightest dent, as if I expected it to.

One often cited case of a beneficial mutation is the sickle-cell anemia. Kent Hovind, in a debate with Michael Shermer, mocked this example by comparing it to being beneficial in the sence of cutting off your feet so you do not get athlete’s foot. — But it’s not so simple. Kent Hovind apparently is ignorant of the qualifiers that determine whether or not the sickle-cell mutation is beneficial or not. If the mutation is in the heterozygous state, then the mutation is detrimental causing disease and early death. However, if the mutation is heterozygous, then that causes its carriers to be resistent to infection and malaria.

One really famous example of a beneficial mutation is the CCR5-Delta 32. This mutation occurs in chromosome three in the human genome. Individuals that carry this particular mutation are resistent to the HIV virus. The heterozygous variant of this mutation is able to slow down the progression of the HIV virus while the homozygous version of the mutation causes immunity to the virus. — It is obvious that the claim made by Harun Yahya in his writings is wrong. There are several examples of beneficial mutations. It has even gotten to the point that some Creationists now admit that they in fact exist, but they then try to put qualifiers on it.

Anyway, now that Creationists have accepted that mutations can be beneficial, they now changed tactics in order to salvage their ever evolving creation model. — One creationist from CMI, while talking about the CCR5-Delta 32, tries to work his way out by saying,

However, it clashes irreconcilably with the evolutionary view that the accumulation of mutations over time brings about upward evolution (increasing functional complexity).

 . . . And then later, he then cites a paper from Nature which mentions a downside to this particular mutation. The implication he seems to be trying to give is that because it can be associated with primary sclerosing cholangitis, then therefore it cannot be count as evidence. — Creationists make similar claims about antibiotic resistence of bacteria, saying that these mutations lead to a “loss of function.”

What these excuses show is a lack of understanding of how Evolution works with mutations. As I have already pointed out in a previous post, evolution doesn’t necessarily lead to increased complexity, though it may. But there is no pre-ordained goal. All that matters is if the change is heritable, and if it is, then that works as evolutionary change. — Also, no one has ever said that mutations that lead to evolutionary change cannot have a downside. There will always be a downside. What matters is if the variation is beneficial or good enough to survive in a certain environment. In an enviroment where there is plenty of AIDS, the CCR5-Delta 32 mutation would be beneficial. Natural Selection will favor those particular individuals that carry it.

Finally, there is Gene Duplication. I know that Creationists would love to pounce on this example and say “It’s just duplicated information.” — I wonder if these same Creationists would be interested in the fact that over 97% of human genes are duplicates. Anyway, gene duplication offers raw material for Evolution and mutation, though it is true that high rates of duplication often lead to high rates of gene loss also, (a fact that would be useless for Creationists to hijack for reasons mentioned above.) What happens is, a gene gets duplicated, and then the duplicate copy has no selection pressures, so it is now free to evolve and mutate on its own, though the gene doesn’t always survive.  

I’m sure that Creationists would love to object to new function ever being derived from duplicated genes, but the fact is that it does happen. A good example is the Eosinophil Cationic Protein (or the ECP) which is toxic to bacteria by making their cell mambranes porus. Also, it is useful in the management of Asthma, despite it’s limitations. — Then there is the Eosinophil-Derived Neurotoxin (the EDN) which helps to prevent viral infections, though it’s accumulation in the intestine is associated with tissue loss.

Furthermore, observations in the genomes of bacteria only aid the conclusion that gene duplication is a viable mechanism for Evolutionary change, as the divergence of duplicated enzymes seems to have been a main contributor -though not no only one-  to the causation of new species of bacterium.

One need not be a geneticist to research the claims of anti-evolutionists to come to the realization that almost everything they claim about mutations is spurious. Even though it is true that most mutations are harmful, it is also true that in certain environments some can be quite beneficial in which cases natural selection will favor them. Some gene duplicates also show neofunction completely debunking the idea that nothing new arises from mutation.

References:
Evolution and Disease, from ChemHeritage.org
Genetics Demystified, page 151. By Edward Willett
Beneficial Mutation, by Ningthoujam Sandhyarani. From Buzzle.com
Beneficial Mutations, from SkepticWiki.
Examples of Beneficial Mutations in Humans, from The Evolution Evidence Page.
Almost all human genes resulted from ancient duplication, by Roy J. Britten, from the Proceedings of the National Academy of Sciences.
Gene Duplication and Evolution of Gene Function, from Evolution and Developement Group.
Evolution by Gene Duplication, by Jianzhi Zhang, from TRENDS in Ecology and Evolution. Also see Positive Darwinian Selection after gene duplication in primate ribonuclease genes, by Jianzhi Zhang, Helene F. Rosenberg, and Masatoshi Nei, from the Proceedings of the National Academy of Sciences.
Eosinophil cationic protein: Is it useful in asthma? A systematic review, by Gerald C.-H. Koha, Lynette P.-C. Shekb, Daniel Y.-T. Gohb, Hugo Van Beverb, David S.-Q. Koha.
Eosinophil Derived Beurotoxin (EDN)
Evolution by leaps: gene duplication in bacteria, by Margrethe H Serres, Alastair RW Kerr, Thomas J McCormack, and Monica Riley. From Biology Direct.


A New Challenge to a Creationist

Lately, I have been commenting on  a Creationist blog, defending Evolutionary theory from Creationist distortions. Of course, one may wonder why I would take the time, and endure the headache of defending the fact of Evolution when arguing with Creationists is often a futile crusade. Well, I guess my reasons are that 1) somebody has to do it, and 2) I’m a glutton for punishment. I like to argue my case.

For the last few months, Eelco, who often comments on the Creationist blog has been issuing a few questions to Michael (the Creationist blogger) who has completely ignored them. In fact, Michael rarely ever — if even ever — engages in discussion with anyone who disagrees with him. The questions Eelco asks Michael on every post are,

(1) Blog readership numbers ?

(2) Your qualifications to discuss any scientific subject, in response to the challenge to Olorin.

(3) A substantive review of Signature in the Cell, promised for August 2009.

(4) outstanding question from Upson Downes on mitochondrial Eve.

Sounds fair enough, no? — Olorin, who Eelco mentions in number two was another frequent commenter who always took Michael to task, and who seems to now been blocked from posting comments anymore.  Personally, I am waiting for Michael to answer Eelco, but I’m not holding my breath.

UPDATE: Olorin was banned from posting on the blog temporarily. He now has been unblocked, I imagine because of preasure that Michael has been feeling about banning him in the first place.

But now I have my own separate challenge to Michael. I refuted Irreducible complexity in my comments on his blog, and I never have gotten him to respond to me. All he did was respond to a fellow Creationist by quoting the long-refuted Michael Behe, and then he attacked the Science Talk.Origins website saying,

Talking origins is out dated piece of bias and will continue to be outdated while we learn more about nature like the FLAGELLUM.

Just pointing out, Michael couldn’t even get the name of the website right — He called it “Talking origins.” It’s Talk Origins. But I digress…

Realizing that he completely ignored EVERYTHING I said, and every argument made against Irreducible Complexity, all he does is attack a science website, and then pull out the obvious “We’re learning more about the flagellum!!” — Well, no dip!! And for some reason, he wants to treat any new discovery about the flagellum as bad for Evolution, and therefore good for Creationism, which he has no basis for.

Well, anyway, I responded to him saying,

The only bias Talk.Origins has is in favor of real scientific research.

I already showed in an earlier comment that flagellum is NOT irreducible. . . Earlier, I pointed out,

An Important fact that ANYONE here has yet to mention is that the flagellum IS NOT EVEN IRREDUCIBLE. — In 1988, G. Kuwajima was able to remove ONE-THIRD of the 497 amino acids from the flagellum, AND IT STILL WORKED PERFECTLY!!!!! . . . Also, we know that the L and the P-rings can be taken away from the flagellum, and it will STILL work. . . .

Michael, if you want to cry “BIAS!!!” then you should do so ONLY AFTER refute this fact that I pointed out.

From now on, i will be issuing a similar challenge to you that Eelco has issued to you, and one you have FAILED to take on. . . except it will be awaiting your refutation of the facts I pointed out about the REDUCIBILITY of the flagellum.

That’s my challenge to him. Will he take me up on it? I’m not holding my breath. Probably like a good Creationist, he will just pretend that it isn’t there, like he does with Eelco’s challenge.


The Truth on the Cambrian “Explosion”

The fifty-three million year period known as the Cambrian is important to the fields of geology and biology because that was when many major groups of kinds of creatures with hard parts and shells, appear in the fossil record. This has been called the “age of trilobites” which were marine arthropods. — During this period of time, there was a unique episode in the history of  life, an apparent evolutionary radiation in which life seems to “explode” in the fossil record. Complex marine animals with hard, preservable parts appear over a rapid span of time in the geological record. This event has been called the Cambrian “explosion.”

At the time Charles Darwin published Origin of Species in 1859, the fossils in the Cambrian were the oldest known ancient life, and paleontology and research in the fossil record hadn’t advanced as much as it has recently. — Darwin himself commented on it saying,

To the question why we do not find rich fossiliferous deposits belonging to these assumed earliest periods prior to the Cambrian system, I can give no satisfactory answer. . . . Nevertheless, the difficulty of assigning any good reason for the absence of vast piles of strata rich in fossils beneath the Cambrian system is very great, and may be truly urged as a valid argument against the views here entertained.

Darwin’s statement, that the lack of fossils before the Cambrian, could be used as “a valid argument” against his theory has struck a chord with critics of Evolutionary theory into the present. In fact, it is hard to find many Intelligent Design and Creationist publications that do not talk about the apparent lack of fossil life before the Cambrian, using it as a “refutation” of Darwinian Evolution — “Darwinism,” as they call it.  The apparent radiation of life that occurred called the Cambrian “explosion” is what they appeal to saying that this was the fauna in this strata appeared “all of a sudden, with no evolutionary ancestors.”

If it could be shown that animal species, in fact, appeared without any kinds of evolutionary ancestors, then Evolutionary Theory would be in trouble. That is a fact. However, if the scientific literature were to show that these fauna had viable ancestors, then there is no problem for the scientific consensus.

First of all, it should be pointed out that the Cambrian “explosion” was only explosive in geologic terms. It is usually estimated to have lasted between 10 to 25 million years —- which is a far cry from the impression that Intelligent Design proponents attempt to give when they say that phyla appear “all of a sudden.” Though rapid in geologic terms, it is hardly rapid on the time scale, and it is not far-fetched to allow plenty of evolution within that time period. It would appear that Antievolutionists are confused by the usage of the word “explosion.”

The claim that phyla appeared “all of a sudden with no viable ancestors” would also be damaging . . . if it were true. But it is not. There is sufficient evidence for animal life before the Cambrian explosion:

  • Complete fossil embryos pre-dating the Cambrian “explosion” by 10 million years were discovered in 2006, and show that animal complexity was already starting to bloom. Fossil embryos are a rare enough find without them being complete.
  • There are plausible pre-Cambrian ancestors for trilobites. For example, there are the Spriggina floundersi, the so-called “Soft-bodied trilobite,” as well as Parvancorina. — Parvancorina is classified, interestingly enough in the Kingdom Animalia, and was possibly even an arthropod. — Also, to make matters worse, there are many transitions between trilobites which are extremely diverse and themselves indicate plenty of Evolution, not just during the 300 million years of their existence, but also during the Cambrian period.
  • Even if non of the examples listed in the last example above were not arthropods or ancestral to trilobites, there is still proof that arthropods did in fact exist before the Cambrian period. Arthropod trace fossils have been found in Nevada in strata dating to 30 million years before the Cambrian, proving that there were animals with legs much earlier than once thought. — Amusingly, some Creationists have attempted to use this one example to refute the Evolution timeline not realizing that this find did more harm to the Creationist argument of the Cambrian “explosion.”
  • There is new fossil evidence of bilateral animals which was recovered from the Doushantuo Formation in China dating from between 40 and 55 million years before the Cambrian. The specimen, called Vernanimalcula, had features like a mouth, a gut, an anus as well as surface pits. This would itself show the Cambrian was not the starting point for complex life.
  • Newly discovered “chemical fossils” have demonstrated evidence that Sponges, as the first Animal life, had already existed around 635 million years ago, or between 90 to 100 million years before the Cambrian “explosion.”
  • The Cambrian “explosion” just doesn’t stand up to the genetic evidence. Molecular clocks indicate a more ancient starting point from between 800 million to 1.2 billion years. This indicates that the fossil record has plenty of gaps, though genetics seems to compensate for what is lacking to a certain extent.

Another detail to consider is that it is plausible that, even though speciation seemingly did pick up during the radiation, it is may in fact not be anything special when compared to other similar radiations that occurred. — Using trilobites as a statistical basis, Bruce S. Lieberman concluded that “speciation rates among olenellid trilobites in the Cambrian radiation were not unusually high.”  He then also said that if these results can be extended to other groups, then special rules aren’t necessary to explain the Cambrian “explosion.”  — This, in my opinion, falsifies the Creationist impression of  rapid and sudden appearance.

Since it is widely agreed by biologists that the Cambrian “explosion” was a real event, there remains the problem of  attempting to explain what caused it, and these explanations are controversial in the scientific community. Plenty of them have to do with environmental changes such as “Snowball Earth”, and also some have proposed that an increase in levels in oxygen in the atmosphere allowing big-bodied animals to thrive. This second proposal could fail assuming that the big-bodied Ediacaran fauna (existing 30 million years before the Cambrian) are in fact animals. One model indicates it -as well as other radiations- may have “changes in the pattern of gene regulation.” On the other hand, indications show that Hox and other developmental control genes were already in existence before the radiation, though genomic repattering during the early Cambrian which involved some key genes and regulators.

But then again, there are scientists that are starting to question whether or not it was even a real event based pre-Cambrian fossil evidence as well as genetics, a lot of which is given above. Naturally, if this is the case, then there is no need to explain it, much less resort to the supernatural.

Any objective look at the Scientific evidence shows that the so-called Cambrian “explosion” cannot be used as evidence for a “creation event” because of its suddenness.  As a matter of fact, some of the fossil finds would seem to muffle the “explosiveness”  since it is now clear that complex life existed at least around 40 to 55 million years before. The implications of this is that there are possible evolutionary ancestors to the Cambrian multicellular life.  — Antievolutionists should update their claims if they want to retain any credibility.

References:
The Cambrian Period: An Explosion of Life, from fossils-facts-and-finds.com
Trilobites, from C&J Fossils.
Frequently Asked Questions About Evolution, from PBS.org.
Embryo Fossils Reveal Animal Complexity 10 Million Years Before Cambrian Explosion, from Physorg.org
Origins of Trilobites by S.M. Gon III. From Trilobites.info.
Earliest Footprints Ever Found, from RESEARCH.
Signs point to sponges as earliest animal life, from MIT News.
Evolutionary Trends in Trilobites, by S.M. Gon III, From Trilibites.info.
Small Bilaterian Fossils from 40 to 55 Million Years Before the Cambrian, by Jun-Yuan Chen, David J. Bottjer, Paola Oliveri, Stephen Q. Dornbos, Feng Gao, Seth Ruffins, Huimei Chi, Chia-Wei Li, and Eric H. Davidson. From Science. Also, see The Early Evolution of Animals by David J. Bottjer, from Scientific American.
Molecular Clocks Do Not Support the Cambrian Explosion, by Jaime E. Blair and S. Blair Hedges, from Oxford Journals.– Also see Testing the Cambrian explosion hypothesis by using a molecular dating technique, by Lindell Bromham, Andrew Rambaut, Richard Fortey, Alan Cooper, and David Penny. From the Proceedings at the National Academy of Sciences.
Taking the Pulse of the Cambrian Radiation, by Bruce S. Lieberman From  Integrative and Comparative Biology
Explaining the Cambrian “Explosion” of Animals, by Charles R. Marshall, from Annual Reviews.
Adaptive walks in a gene network model of morphogenesis: insights into the Cambrian explosion, by Solé RV, Fernández P,  and Kauffman SA. From the International Journal of Developmental Biology.
Fossils, molecules and embryos: new perspectives on the Cambrian Explosion, by James W. Valentine, David Jablonski and Douglas H. Erwin.
Plant and Animal Evolution.

Recommended Reading:
Transitional Forms and the Evolution of Phyla, by Glenn R. Morton, from American Scientific Affiliation. Published in Perspectives on Science and Christian Faith.
The Precambrian to Cambrian Fossil Record and Transitional Forms, by Keith Miller, from American Scientific Affiliation. Published in Perspectives on Science and Christian Faith.
Re:Cambrian Explosion, by Keith Miller, from the American Scientific Affiliation.


Debates Between Scientists and Creationists

Scientists have overwhelming evidence to demonstrate that Evolution is not only a theory, but also a fact. So considering that, how is it that Creationists seem to win the debates? — Of course, a Creationist may simply assume that the Creationist wins because the Evolutionist is wrong. But a better look at the subject shows that this isn’t the case at all. There are several reasons Creationists seem to carry the day, and none of them have anything to do with being on the right side. And there are several reasons why Scientists are reluctant to debate with Creationists, and it isn’t because they are on the “wrong” side either.

If you have studied Evolution and know the scientific method, then you will know how Evolution works — I hope, at least. Therefore, I would also hope that you would also be able to pick out arguments made by Creationists that are totally absurd, though they may seem reasonable to the lay person. I see this happen a lot in Kent Hovind debates. — I just watched one, and I found myself getting a headache when he made an illustration about the “evolution of silverware.” Knowing what was coming, I simply fast forwarded through that. In another video I saw, he debated  Ben Waggoner from the University of Central Arkansas who, although he undoubtedly knew his stuff, was not prepared for the beating he received.  — In fact, the only hostile audience that he had that I know about was when he spoke at Berkley University in which several students called him out.

A major important reason why Creationists seem to win debates is that they seem to usually debate in front of friendly audiences. In other words, most people in the audience have already decided that Evolutionary theory is false, and the reason they are there is to see the “lost” evolutionist get trounced by their champion. — Donald  Prothero, a leading professor of Geology, described a time when he accepted a challenge to debate Duane Gish. In the end, during the questions and answers segment, he received several irrelevant and offensive questions such as “Are you going to hell?” or “Are you a sexual pervert?” The audience was not interested in the evidence, but only in seeing the Evolutionist get defeated. Ultimately, he decided not to debate Gish again since it was a waste of time.

Another reason is that Creationists tend to dominate the debate. They have better debating skills than most Scientists because they have more practice at it. Scientists are usually busy with research, so they don’t have as much time to go out and debate. — Creationists also tend to shoot out too much drivel in only a few seconds which is very difficult to refute as quickly as it gets said. And due to the formats and time limits of these debates, the poor scientist is not free to give an adequate answer.

Creationists shoot out arguments like “Life could not have originated by chance,” and “the big bang is false.” — The bull of Creationists using these arguments is that they are not part of Evolutionary theory, even though Creationists don’t seem to see the difference between Biology and Cosmology.  These arguments are made to leave the impression that the Evolutionist has no basis for his acceptance of Biological Evolution, and that the theory of evolution is therefore nonsense or “stupid,” as Kent Hovind puts it. — Were I to debate a Creationist who brings these two subjects up, I would simply say “I am here to defend Evolution, not the Big Bang, and not Abiogenesis.”

On the occasions that I do talk with Creationists, I usually run into arguments made against strawman versions of evolution rather than the recognized theory at all. One of them is the idea that evolution “must” lead to increasing complexity, and that the Uniformitarian principle (of Geology, not of evolutionary biology) means that accumulation of all geologic layers was all done slowly with no exception. These arguments are common in the Young Earth Creationist community in particular, however they are based on false premises. Evolutionary theory does not make the prediction that everything has to become more complex, and the principle of uniformitarianism (which is Geology, not evolution) does not dictate that all layers took long periods of time to form.

There is also the fact that it is near impossible to give enough information about how evolution works in just one day. There are reasons why evolution related classes such as Biology and Physical Anthropology take whole semesters. It takes whole semesters to teach the basics of these classes. So the playing field for debates is hardly even at all.

Then there is the fact that Creationists tend to move the goal posts on the scientists. — Kent Hovind’s $250,000 challenge is a great example of this. His challenge pretty much says that even if we could produce evolution, abiogenesis, and the big bang in the lab, it still wouldn’t count because we would still have to prove God had nothing to do with it. Considering that I am a Christian, and therefore believe in God, I see this as ludicrous. The requirements are so unreasonable, it is no wonder not many (if any) scientist has even bothered with this challenge. –Also when given antibacterial resistence as an example, he simply said that no matter what, that bacteria would still not be immune to a sledge-hammer, as if Evolutionary theory makes any such prediction.

Then when it comes to the fossil record, he says “Fossils can’t be used as evidence for evolution because you can’t prove they had any kids.” In other words, no evidence is good enough. Also, it demonstrates he has no understanding about why and how fossils are used. Nobody is saying that a particular fossil is our ancestor, but that it has traits we would expect of what a potential ancestor would have. Hovind was positioning himself in a way that he could be able to dismiss any and all evidence for that abominable theory that he despises so that he wouldn’t have to truly deal with it.

The final reason why Scientists don’t debate with Creationists is they just don’t think it’s worth it. — Richard Dawkins, for example, refused to debate with the Muslim Creationist Harun Yahya when he was challenged saying he didn’t want to give him status.  — Also, Kenneth Miller, another top scientist described a time when he accepted a Creationist challenge and asked Steven Gould for help,

I called Steve up and then I explained to him that I was preparing for a debate with a scientific creationist. And I asked him if he could help me out with a couple of arguments. And to my amazement, he stopped me short. And he said, `Ken, I’d like to remain your friend. I’d like to be on good terms with you, but I don’t think it’s wise to debate these guys. I don’t think it’s appropriate to give them a platform for their misguided and misleading views. And if you’re going to debate this fellow, I won’t help you, I won’t provide any assistance, and I won’t even talk with you.’

The truth is, Scientists don’t want to debate Creationists simply because they don’t want to give Creationists status where status is not due. It is not because they are “wrong” and have no evidence to support their claims. It is that the playing field is hardly level which, by the way, also doesn’t make for a good debating forum when you have a whole audience that is intellectually hostile to the scientist.  — Also, another reason why they may not want to debate with them is because it may create the impression that Evolutionary theory is controversal in the scientific community.

References:
29+ Evidences for Macroevolution: The Scientific Case for Common Descent, by Douglas L. Theobald, Ph.D. From the Talk.Origins Archive
Evolution: What the Fossils Say and Why it Matters, pages 46 and 47, by Donald R. Prothero.
Kent Hovind’s $250,000 Offer, by John Pieret, From the Talk.Origins Archive
Scientists Hesitant to Debate Intelligent Design, from National Public Radio.