Friday, January 28, 2011

Evolutionary Pressures

I was recently asked a few questions about evolutionary pressures in Darwinism. Here’s the majority of my response (certain personal parts have been removed from the original, and some of the grammar has been edited):

When it comes to evolutionary pressures, it is important to keep in mind that even Darwinists must acknowledge the limitations of such pressures. While you listed the example of a giraffe’s neck or a cheetah’s speed, even those run into the problem of “islands” of fitness. While we think of evolution as progressing to better and better organisms, the fact is that this sort of concept is highly anthropomorphic because even secularists want humans to occupy the “highest” niche. For ease of understanding, however, I believe it’s better to reverse the direction.

Suppose that you have a ball on the top of a steep hill. If you release the ball, it will roll down the hill because of the force of gravity. For this illustration, let’s assume that the ball is a species’ genetic characteristics, gravity is evolutionary pressures (such as the environment, competition, and anything else that would result in survival of the fittest), and the farther down the hill you progress the more highly suited the species is for the environment.

Now, if the hill was perfectly smooth, the ball would roll all the way to the base and you’d have the perfect organisms being produced at sea level. But that’s not a realistic perspective. I live in Colorado, and in my backyard stands Pikes Peak. Suppose we were to start with a ball on the top of Pikes Peak and we were going to try to roll the ball to the ocean using nothing but gravity. Would that work?

Obviously not. For while the ball could roll quite some distance from the top of the Peak, eventually it will encounter a section that is uphill in all directions before it gets to the ocean. In fact, there are countless uphill sections from Pikes Peak to the sea, no matter which way you try to roll the ball. If you’re lucky, you might be able to get the ball to roll from the summit (at just over 14,000 feet elevation) down to maybe 10,000 feet, although in most cases you probably wouldn’t get it to roll more than a few dozen feet before it would be stopped by some rocks creating a local valley.

While the actual distance isn’t really that important, the point is that eventually the ball will settle into a localized valley where every direction around the ball is uphill. Let’s stipulate the ball we drop runs into this problem at 10,000 feet elevation. Now obviously, 10,000 feet is long way above sea level, where the ball “wants” to go. If it had the means, it would roll down to sea level—but locally, it is trapped. Every direction is uphill. It cannot go lower using gravity alone, because it is stuck in its valley.

Evolution runs into the same problems. There are valleys that a species will fall into, where they could develop into an even more “advanced” species, but they are so adapted to their niche that any movement the species makes is against natural selection. That is, once in the valley, natural selection will keep the organism in the valley, and ultimately natural selection itself will select AGAINST further evolution.

Ernst Mayr pointed this out when talking about gene flow and genetic drift:

Gene flow is a conservative factor that prevents the divergence of only partially isolated populations and is a major reason for the stability of widespread species and for the stasis of populous species.

...

In a small population alleles may be lost simply through errors of sampling (stochastic processes); this is known as genetic drift. Indeed, such a random loss of alleles may occur even in rather large populations. This is usually of no consequence in widespread species, because such locally lost genes will be quickly replaced by gene flow in subsequent generations. However, small founder populations, beyond the periphery of the range of a species, may have a rather unbalanced sampling of the gene pool of the parental population. This may facilitate a restructuring of the genotype of such populations.

(Mayr, Ernst. 2001. What Evolution Is . New York: Basic Books. p 98, 99).
Notice, therefore, that in the vast majority of populations, natural selection will seek to keep organisms AS THEY ALREADY ARE. In fact, Mayr says:

With drastic selection taking place in every generation, it is legitimate to ask why evolution is normally so slow. The major reason is that owing to the hundreds or thousands of generations that have undergone preceding selection, a natural population will be close to the optimal genotype. The selection to which such a population has been exposed is normalizing or stabilizing selection. This selection eliminates all of those individuals of a population who deviate from the optimal phenotype. Such culling drastically reduces the variance in every generation. And unless there has been a major change in the environment, the optimal phenotype is most likely that of the immediately preceding generations. All the mutations of which this genotype is capable and that could lead to an improvement of this standard phenotype have already been incorporated in previous generations. Other mutations are apt to lead to a deterioration and these will be eliminated by normalizing selection.

(ibid, 135)
So, on the one hand, natural selection is supposed to be the driving force behind evolution, but on the other hand, natural selection is the very thing keeping organisms from changing. Indeed, as far as the second method goes, I firmly accept the validity of natural selection! We can actually observe that process in work. Natural selection reduces variety; it does not create it. Indeed, Mayr acknowledges this, calling selection “an elimination process”:

Selection is not teleological (goal-directed). Indeed, how could an elimination process be teleological?

(ibid, 121)
So, whether one accepts Darwinism or Creationism, it only makes sense that organisms right now are as close to their “peak” (or, given our illustration, as close to sea level) as possible. Under Creationism, it’s because they were created that way; under Darwinism, it’s because they’ve had millions of years to evolve to their environment. In both instances, natural selection now seeks to keep organisms the way they are, because they are already as adapted as they can be to their environment. The only way to change this is to change the environment in some radical way.

But notice that most of the radical alterations of an environment do not grant us any new species, but rather only makes certain other species go extinct. For instance, the dodo bird was easy prey when Westerners arrived with their pets. The dodo didn’t evolve—it died out. On the other hand, when rabbits were introduced into Australia, their population exploded. In the process, they’ve driven several native species to the brink of extinction too. But notice that neither the rabbit themselves, nor the organisms that are dying out, have significantly altered their genotype in the face of this extremely different environment. The changes are too abrupt, and even granting Darwinism every advantage, there simply isn’t enough time for the species to garner sufficient mutations to avoid doom. The only way they could would be to have the environment slowly change, giving each species time to adapt to the slowly changing environment. Abrupt changes only result in mass extinction.

As far as your argument from incredulity, that it’s unlikely that “mistakes” would result in these types of happy occurrences, I believe that is a fairly strong argument, actually. First of all, life looks like it is designed. This is the strength of Paley’s watch argument. The default assumptions any reasonable person would make, when looking at life, would be to conclude that it is designed. As a result, the impetus really is on the Darwinist to prove that this sort of thing can happen without teleology. When something appears to be designed, the default is to assume that it is designed until it is proven otherwise, so the Darwinism does have the burden of proof here.

Furthermore, the Darwinist himself cannot escape teleological terminology. In fact, Darwinism is seeped with teleological terms. The very fact that they say, “Nature selects the fittest organism” is itself a teleological claim. First of all, there is the claim that nature is actually doing a selection, and selection implies a choice. Secondly, what is selected is the “fittest” and “fittest” implies that the organism has a specific role to play, and it plays that role “the best.” So, “natural selection” itself is a term loaded with teleology—it is claiming that nature is choosing the best organism to play a specific role. But that simply IS an affirmation of design. Darwinists try to get around this by claiming they are just using language metaphorically, but I have yet to find anyone who can explain Darwinism without resorting to teleological statements. And I daresay that if you cannot describe a process without reference to design, then you’re better just admitting that what you’re looking at IS design.

I mean, put it this way. There are certain crystals that have properties that make them take on very cool geometrical shapes and patterns. We know that these processes occur naturally without any apparent design in nature, and we can mimic this in a lab and create these crystal shapes ourselves, etc. A physicist may use teleological language at some point to talk about it—say, “A salt crystal wants to be cubic.” But the same physicist can also describe the chemical bonds and how the sodium and chlorine react to create this structure without using any teleological language at all, if the physicist so chooses.

But I have yet to read a biologist who can explain Darwinism in that way. Now, some may very well claim that trying to explain an entire ecosystem is vastly more complicated than trying to explain the interactions of two elements forming a salt crystal, so the biologist is forced to use teleological metaphors. But given that biology needs to deny teleology, the impetus really is on them to stop using teleological language.

So, as I said, I see nothing wrong with you arguing from incredulity. You are perfectly justified in being incredulous. The Darwinist has told you a counter-intuitive story that he supports with language that he specifically says is disallowed. Why shouldn’t you be incredulous?

More to the point, there are many examples that seem to affirm Behe’s irreducibly complexity argument. It is incumbent upon the Darwinist to explain how those types of systems can arise. The Darwinist likes to just assume Darwinism is true, and then fit all observation into that theory. But that is begging the question. To be scientific, he must derive his theory from the observations, not force the observations to fit his theory.

42 comments:

  1. "No potential example of a supposed irreducibly complex system can, even in theory, demonstrate that it did not evolve from less complex components. One can only demonstrate how a system can be reduced, or claim ignorance as to how it can be. Irreducible complexity is therefore an argument from ignorance and, more specifically, a God of the gaps argument." (wiki.ironchariots.org)

    Even if a Darwinist could not explain how these systems arise, that wouldn't make your magic wand any more likely.

    ReplyDelete
  2. TAM said:
    ---
    "No potential example of a supposed irreducibly complex system can, even in theory, demonstrate that it did not evolve from less complex components."
    ---

    I'm surprised that the fact this sentence renders Darwinism impossible to falsify slipped past your intellect.

    You also said:
    ---
    Even if a Darwinist could not explain how these systems arise, that wouldn't make your magic wand any more likely.
    ---

    Using pejorative language instead of interacting with an issue is a sure sign that you've lost the debate and are too dishonest to admit it.

    ReplyDelete
  3. BTW, your quoted statement is also flat out false. It would be like arguing, "You cannot rule out that the body found with a bullet in the brain did not occur by spontaneous natural causes. It is an argument from ignorance, and, more specifically, a human agency of the gaps argument."

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  4. Peter, Darwinism is easly falsifiable. If I may borrow a quote from Jerry Coyne: "Every day, hundreds of observations and experiments pour into the hopper of the scientific literature. Many of them don't have much to do with evolution - they're observations about the details of physiology, biochemistry, development, and so on - but many of them do. And every fact that has something to do with evolution confirms its truth. Every fossil that we find, every DNA molecule that we sequence, every organ system that we dissect, supports the idea that species evolved from common ancestors. Despite innumerable possible observations that could prove evolution untrue, we don't have a single one. We don't find mammals in Precambrian rocks, humans in the same layers as dinosaurs, or any other fossils out of evolutionary order. DNA sequencing supports the evolutionary relationships of species originally deduced from the fossil record. And, as natural selection predicts, we find no species with adaptations that benefit only a different species. We do find dead genes and vestigial organs, incomprehensible under the idea of special creation. Despite a million chances to be wrong, evolution always comes up right. That is as close as we can get to a scientific truth" [my emphasis]

    There are many arguments in support of theism and, no doubt, many arguments in support of your preferred flavor but "irreducible complexity" is not one of them. It is a pure synonym for the argument from ignorance. It is simply arriving at a point (any point, take your pick) and deciding that science can't drill down any further. Good luck with that and I'll look forwad to visiting this blog after life is finally created from inanimate elements in a lab setting. But .... wait a minute. We already know that all life is cerated from inanimate elements - don't we? We just don't know how the first replicating molecules arose. Once that question is answered (and, rest assured, it will be answered within the next century if religious fanatics don't blow us all up first) what will be your answer? "I guess we now know how God did it"?

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  5. I should add that creationism does an excellent job of creating Christian apostates. No outside interference required. Just wind it up and let it go ...

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  6. For your next post, please explain how human biology permitted Methuselah to live for 969 years.

    This is like shooting fish in a barrel.

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  7. AM,

    What books by ID theorists have you actually read?

    ReplyDelete
  8. The Atheist Missionary said...

    "For your next post, please explain how human biology permitted Methuselah to live for 969 years."

    For your next comment, please explain how human biology didn't permit Methuselah to live for 969 years.

    I assume that you're a biogerontologist by training, who does cutting-edge research on the mechanisms of aging.

    ReplyDelete
  9. The Atheist Missionary,

    The fact that you would cite the Iron Chariots web site, then cite Jerry Coyne so uncritically and without any documentation, doesn't reflect well on your knowledge of the issues, your research, or your respect for the people you're disagreeing with, among other things. In a previous discussion that you left, I directed you to a thread in which we discussed the unreliability of the Iron Chariots site. Peter has already responded to Coyne's book, and has said a lot about the alleged evidence for evolution in other threads at this blog. See here, for example. You're ignoring most of what Peter has said here and nearly everything he's said elsewhere.

    What you keep doing, in one thread after another, is raising common objections that we and others have answered many times. You make little or no effort to interact with the responses. As Peter said, that's not just pathetic. It's also dishonest.

    ReplyDelete
  10. Gentlemen, first of all, let me make it clear that I (like probably 99% of those who visit this site) am not a professional biologist. I've read Darwin, Dawkins and Coyne explain how the theory of evolution works. I've read Meyer’s Signature in the Cell and I didn't discern any argument aside from "there are things which science can't yet explain and I consider those things to be irreducibly complex". I haven't read Behe but I have heard him speak and he is more vague than Meyer. If anyone here discerns a more focused thesis from these fellows, I would be obliged if you could share it with me.

    As far as asking me to explain how human biology would prevent someone from living to be over 900 years sold, I will throw an easy lob back at anyone who care to answer it: please give me the name of one person on this planet with a Ph.D. in the natural sciences who has written a peer reviewed paper supporting this hypothesis. Just one please. A cite would be greatly appreciated.

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  11. That's not an intellectually serious summary of Meyer's argument.

    And even Philip Kitcher admits that peer review is a sociological convention, not a scientific criterion.

    By your own admission, you're not qualified to evaluate Methuselah's longevity even from a naturalistic standpoint.

    Yes, it's easy for you to try to lob the ball back into our side of the court. But you don't get to treat the burden of proof so one-sidedly.

    As far as Methuselah is concerned, we don't need alternative evidence to establish his longevity. Rather, if our source of information is reliable, then that validates the claim.

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  12. The Atheist Missionary wrote:

    "I will throw an easy lob"

    You don't do much else.

    You're still ignoring most of what we've said, as you've done in previous discussions, and you're moving the goalposts again by asking for a peer-reviewed paper about people living a patriarchal lifespan. You aren't just evading the issues Peter was discussing. You're also drifting away from your own original claims. You change the subject, then change it again. You expect other people to do far more to support their own views than you do to support your own. Your behavior is shameful.

    It's not much different than the behavior of a lot of non-Christians who post here.

    ReplyDelete
  13. A shameful pitcher throws a lob and ... a swing ... and a miss. Anyone else care to try?

    ReplyDelete
  14. My original claim was that evolution is easily falsifiable and I, not being a professional biologist, relied on Coyne's quote in support of that assertion. Specifically, does anyone contest the following claim: "Every fossil that we find, every DNA molecule that we sequence, every organ system that we dissect, supports the idea that species evolved from common ancestors" and, if so, on what basis? Cites please. I like those.

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  15. You could start with Henry Gee's critique of evolutionary genealogies.

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  16. ID theorists like Behe and Dembski set forth criterion for detecting intelligent design. They've defined the criterion and argued for its reasonableness by pointing to similar methods in other sciences (like forensic science and SETI).

    A GoG argument says "I don't know how this works so God must have done it." But ID theorists are saying "Given what we know about Darwinian mechanisms, Darwinism can't account for this fact. Given what we know about intelligent agency, it can account for this fact."

    If that constitutes a GoG argument, then I don't see how the entire field of science isn't one big gaps argument. Every theory in science is just a gap argument, since every theory in science discounts theories based upon how well it fits the scientist's understanding of the data and adopts theories based on how well it fits into what a scientist knows another theory is capable of accounting for.

    Doesn't ignorance factor into every postulation, since scientists are always going to be ignorant of whether some new bit of data will support a theory and their supporting one theory over another will inevitably rest (at least in part) upon that ignorance?

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  17. The Atheist Missionary said:

    "No potential example of a supposed irreducibly complex system can, even in theory, demonstrate that it did not evolve from less complex components. One can only demonstrate how a system can be reduced, or claim ignorance as to how it can be. Irreducible complexity is therefore an argument from ignorance and, more specifically, a God of the gaps argument." (wiki.ironchariots.org)

    Even if a Darwinist could not explain how these systems arise, that wouldn't make your magic wand any more likely.


    In addition to what others have said:

    1. I don't know if you have a problem with basic reading comprehension, but irreducible complexity wasn't Peter's sole argument against evolution in his post. So it's not as if this is a "magic wand" argument against evolution. Or to put it another way: even if the irreducible complexity argument isn't a good argument, it wasn't the only argument Peter raised against evolution in his post.

    2. The quote you cite cuts both ways. If it's an argument from ignorance for the contra-evolutionist, then it's similarly an argument from ignorance for the pro-evolutionist. If the contra-evolutionist can't say an irreducibly complex system wasn't due to evolution, then a pro-evolutionist can't say an irreducibly complex system was due to evolution.

    3. Moreover, ID proponents don't necessarily always use irreducible complexity to argue for ID, per se, but against evolution as well.

    Gentlemen, first of all, let me make it clear that I (like probably 99% of those who visit this site) am not a professional biologist

    I wouldn't be so sure about that. There are at least a couple of people here who do have a significant background in biology. People who do work in the field. People in doctoral programs conducting research. People in medical school too. You'll see them comment from time to time. They can make themselves known if they'd like.

    please give me the name of one person on this planet with a Ph.D. in the natural sciences who has written a peer reviewed paper supporting this hypothesis. Just one please. A cite would be greatly appreciated.

    1. There are plenty of scientists who have published papers and articles in peer reviewed scientific and medical journals which lay the groundwork for the possibility that human lifespans might be prolonged beyond what we'd consider "normal" these days. For example, Valter Longo. Or Cynthia Kenyon. Or Tom Kirkwood. Even last year's Nobel Prize winners in physiology or medicine, Elizabeth Blackburn, Carol Greider, and Jack Szostak, who may or may not necessarily think it's possible (I don't know their personal views), nevertheless have published work that could potentially lend support to such a possibility.

    I'm not suggesting I necessarily agree with their work. But it's a more than adequate response to your supposed challenge.

    2. Besides, what do you know about senescence and aging anyway? Are you conversant in topics like the Hayflick limit, telomerase and telomere shortening, oxidative stress, free radicals like reactive oxygen species (e.g. superoxides, hydroxyls) and mitochondrial damage (e.g. such as in the electron transport chain), pharmaceuticals which attempt to mimic caloric restriction (e.g. 2-deoxyglucose which blocks glucose metabolism), etc.? This is just for starters. We haven't even talked about other topics such as aging in neurological diseases like Alzheimers, or oncology which is relevant given that cancer cells essentially "live forever," genetic defects like Cockayne's syndrome or Werner's syndrome which involves a mutated gene (WRN) thus accelerating the aging process, and much, much more.

    ReplyDelete
  18. The Atheist Missionary said:

    Cites please. I like those.

    Why don't you do the legwork yourself? Just search PubMed or Web of Science or somesuch. Look for your own journal articles.

    ReplyDelete
  19. I am happy to commend Henry Gee for your readers' continuing education on the fact of evolution: http://www.nature.com/nature/newspdf/evolutiongems.pdf?gclid=CMuynbKpuZgCFQaA3godSxLYZQ

    ReplyDelete
  20. "please give me the name of one person on this planet with a Ph.D. in the natural sciences who has written a peer reviewed paper supporting this hypothesis. Just one please. A cite would be greatly appreciated."

    Of course, anyone who's had the misfortune of trying to discuss these kinds of issues with unbelivers knows what goofy smokescreen this is. For as soon as a skeptic encounters a creationist or ID opponent who has a degree in biology or any other sciences, they dismiss them as nutcases anyways. You'd have to be truly naive to think that we haven't seen this kind of evasion before.

    ReplyDelete
  21. The Atheist Missionary said:

    I am happy to commend Henry Gee for your readers' continuing education on the fact of evolution: http://www.nature.com/nature/newspdf/evolutiongems.pdf?gclid=CMuynbKpuZgCFQaA3godSxLYZQ

    I can't believe you work in the legal field given the paucity of your reading comprehension let alone logical reasoning.

    If someone positively cites Christopher Hitchens condemning fundamentalist Islam, does that mean the same person would also commend Hitchens' atheism? No, not necessarily.

    Likewise Steve citing Gee's critique of evolutionary genealogies doesn't mean Steve commends other positions for which Gee has argued (e.g. Gee's pro-evolutionism).

    ReplyDelete
  22. AM,

    Nice bait-and-switch. What does Gee have to say about evolutionary genealogies?

    ReplyDelete
  23. Patrick:

    "Perhaps the only fact that all those engaged in aging research will agree on is that the individual lifespan of animals (or at least of mammals) - and of man - is limited by biological factors. It has not required modern experimental science to uncover this fact, it is, for example, stated expressis verbis in Christoph Wilhelm Hufeland's admirable and still contemporary treatise 'Macrobiotics': The Art of Prolonging Life, first published in Jena, 1798. The great physician states clearly and as accepted fact that for each animal species and for mankind there is an upper limit to lifespan, that this limit is fixed, is different and specific to each species and that for man it has not changed since the earliest written records of human history. Recent careful study by phylogenetic analysis, with the help of an empirical equation using brain - and body weight estimations from fossils, has led to the conclusion that for Homo sapiens the maximum potential lifespan (Hufeland's 'absolute' lifespan as opposed to 'relative' or average lifespan of a selected population) has remained unchanged at around 95 years for the past 100,000 years": The biological aging process, H. P. von Hahn, Cellular and Molecular Life Sciences, Vol. 39, No. 1, pp. 47-49.

    Please don't embarass yourself by naming scientists who are engaged studying how the aging process might be prolonged or by regaling me with biological topics you already know that I am not conversant with. Just answer one simple question: are you aware of one PH.D. expert in the natural sciences who has written one peer reviewed paper to suggest that the human lifespan has ever exceeded, say, more than 150 years? You seem to be a smart guy. I'm sure you can answer this simple challenge.

    ReplyDelete
  24. Notice that AM indulges in the framing fallacy, where he tries to win the argument by framing the question in terms favorable to his own position. That's just a rhetorical ruse.

    ReplyDelete
  25. The Atheist Missionary said...

    "I am happy to commend Henry Gee for your readers' continuing education on the fact of evolution."

    Of course, that's a typically addlebrained response from AM. Since he's too dense to get it, let's explain it for him:

    The fact that Gee is a Darwinian is hardly a defeater for my position. I cited him precisely because he is a Darwinian. That makes his concessions all the more significant.

    ReplyDelete
  26. The Atheist Missionary said:

    Please don't embarass yourself by naming scientists who are engaged studying how the aging process might be prolonged or by regaling me with biological topics you already know that I am not conversant with.

    1. Since you admit you're not conversant with "biological topics" let alone a cross-disciplinary topic like cellular senescence and aging which integrates multiple fields and ranges across a wide spectrum, then what's the point? It'd be like trying to explain algebra (or, in fact, more advanced mathematical subjects) to someone who admits they don't know any math. First go and learn some basic addition and subtraction. Learn some multiplication and division. Just for starters. Then come back here and maybe we can talk.

    2. Not to mention you don't appear at all to know how to pick a reliable journal article out from an unreliable journal article. As far as you're concerned, any journal article published by any academic journal is worth citing. It's obvious you don't even know how to conduct a literature review to vet the wheat from the chaff.

    3. Otherwise, yes, you're embarrassing yourself.

    Just answer one simple question: are you aware of one PH.D. expert in the natural sciences who has written one peer reviewed paper to suggest that the human lifespan has ever exceeded, say, more than 150 years? You seem to be a smart guy. I'm sure you can answer this simple challenge.

    1. Once again, you're moving the goalpost. You're asking a subtly but significantly altered version of what you originally asked. Astute readers can compare this question with his previous one.

    2. I cited several secular scientists above. Not to mention gave you resources so you can do your own searching (e.g. PubMed). Put the two together and do your own research.

    3. Okay, fine, I'll lend you a huge helping hand. See here for starters. Check this out too, part of which sums up some of the research:

    "The prospect of halting or at least slowing down the body's ageing processes is not so far-fetched. Several promising scientific developments may lead to interventions that could extend human life expectancy beyond the longest lifespan observed so far: 122 years, a record held by a French woman. Researchers are trying to use the enzyme telomerase to overcome the limit of somatic cell divisions to stop or slow cell senescence (Flanary, 2002; Hayflick, 2003). Others are searching for substances that mimic the effects of caloric restriction, which has been shown to extend the lifespan of mice by up to 30% (Ingram et al, 2004). The Human Genome Project has also provided new targets for pharmaceutical therapies that could slow ageing or prevent various age-related diseases (Guarente, 2003). On the basis of such developments, intervening in the biological process of ageing is now discussed in the scientific literature as a real future possibility (Aaron & Schwartz, 2004; de Grey et al, 2002a)."

    4. So I've called your bluff. Now it's your turn. Why don't you answer the questions we've raised in this combox - if you can.

    ReplyDelete
  27. The Atheist Missionary excerpts the following:

    "Perhaps the only fact that all those engaged in aging research will agree on is that the individual lifespan of animals (or at least of mammals) - and of man - is limited by biological factors. It has not required modern experimental science to uncover this fact, it is, for example, stated expressis verbis in Christoph Wilhelm Hufeland's admirable and still contemporary treatise 'Macrobiotics': The Art of Prolonging Life, first published in Jena, 1798. The great physician states clearly and as accepted fact that for each animal species and for mankind there is an upper limit to lifespan, that this limit is fixed, is different and specific to each species and that for man it has not changed since the earliest written records of human history. Recent careful study by phylogenetic analysis, with the help of an empirical equation using brain - and body weight estimations from fossils, has led to the conclusion that for Homo sapiens the maximum potential lifespan (Hufeland's 'absolute' lifespan as opposed to 'relative' or average lifespan of a selected population) has remained unchanged at around 95 years for the past 100,000 years": The biological aging process, H. P. von Hahn, Cellular and Molecular Life Sciences, Vol. 39, No. 1, pp. 47-49.

    Speaking of "embarrassment," your use of this article is a case in point. Among other problems, this article dates from 1983 (see here or here). We're in 2011. There's been a considerable amount of scientific advance in the intervening years. Advance which in particular challenges the view that "there is an upper limit to lifespan, that this limit is fixed." I've cited some of the challenges above.

    Of course, I'd reiterate I don't necessarily agree with any of this myself. Rather what I've simply done is call your bluff.

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  28. THE ATHEIST MISSIONARY SAID:

    "Just answer one simple question: are you aware of one PH.D. expert in the natural sciences who has written one peer reviewed paper to suggest that the human lifespan has ever exceeded, say, more than 150 years."

    This illustrates AM's chronic inability to think for himself. All he can do is to mindlessly regurgitate the clichés he picked up from Panda's Thumb, Pharyngula, et al.

    Modern scientists can only examine post-Adamic bodies, which are degraded by the curse. They don't have access to the Adamic prototype to furnish their standard of comparison. So AM isn't attempting to engage the Christian position on its own grounds.

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  29. steve writes: Modern scientists can only examine post-Adamic bodies, which are degraded by the curse

    Ah, the curse. Sooner or later the academic debate devolves to an appeal to superstitious munbo jumbo.

    OK, I'll drink your kool-aid. Let's assume that there is an Adamic prototype. Just find one fossilized example and you will throw 150 years of evolutionary theory on its ear.

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  30. THE ATHEIST MISSIONARY SAID:

    "Ah, the curse. Sooner or later the academic debate devolves to an appeal to superstitious munbo jumbo."

    That's not an academic response. It's just one of your cutesy rhetorical one-liners.

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  31. steve, expecting an academic response to "the curse" is like expecting an academic response to the suggestion that there are fairies in my garden. Both assertions are gibberish and devoid of even a scintilla of evidence.

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  32. The Atheist Missionary said:

    OK, I'll drink your kool-aid. Let's assume that there is an Adamic prototype. Just find one fossilized example and you will throw 150 years of evolutionary theory on its ear.

    You're wasting our time.

    You don't respond to our questions. Why should we bother continuing to respond to yours.

    Not to mention you're hardly asking in earnestness. You'd just find yet another ill-conceived objection once we respond anyway.

    All this is in addition to your utter unreasonableness and intellectual poverty.

    Or to put it in words you might better grasp: hey bubba, i reckon yer thinking yer one high falutin' fella, but doggone it if it ain't the truth, you ain't even got peas for brains, that's fer sure!

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  33. "Please don't embarass yourself by naming scientists who are engaged studying how the aging process might be prolonged or by regaling me with biological topics you already know that I am not conversant with."

    This is the punchline to this entire thread.

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  34. The Atheist Missionary wrote:

    “A shameful pitcher throws a lob and ... a swing ... and a miss. Anyone else care to try?”

    I wasn’t swinging at your latest change of subject. I was swinging at your shameful behavior, and I hit it.

    Why are we supposed to follow you down every tangential trail you open up, yet you can ignore our arguments and change the subject as much as you want?

    You write:

    “Cites please. I like those.”

    Like a citation from Iron Chariots? Or posting a quote from Jerry Coyne without any documentation? You don’t come across as somebody who has much interest in evidence.

    ReplyDelete
  35. Good grief, see what I miss when I sleep in on a Saturday?

    The Atheist Missionary, if you don't actually begin to interact with the arguments that have been presented and only continually spout off your stupid one-liners, I'm going to begin deleting all your subsequent posts in this thread.

    Don't worry, I'll leave what you've written so far, because you did such a bang-up job of proving how stupid the average Darwinist is; but this is not your blog, and I'm not going to let you waste my time further.

    ReplyDelete
  36. The Atheist Missionary writes:

    “steve, expecting an academic response to ‘the curse’ is like expecting an academic response to the suggestion that there are fairies in my garden. Both assertions are gibberish and devoid of even a scintilla of evidence.”

    Go read the "No Evidence?" post I’ve linked for you at least three times now. When you’re interacting with people who have argued for the reliability of the Bible as much as we have, it’s frivolous and dishonest to make dismissive comments like the ones you’ve made above. You’re assuming what you haven’t demonstrated. We’ve argued for our view of the Bible at length, and your response is to make vague references to “fairies” and “gibberish”. That’s irresponsible and unconvincing.

    ReplyDelete
  37. The Atheist Missionary said...

    "OK, I'll drink your kool-aid. Let's assume that there is an Adamic prototype. Just find one fossilized example and you will throw 150 years of evolutionary theory on its ear."

    i) Since there was only one prototype, why would we expect to find the fossilized prototype?

    Even from a Darwinian standpoint, how many fossilized prototypes of various species survive? Any?

    ii) Suppose we found a fossilized bone of Methuselah. What do you think that would prove or disprove?

    If the rate of aging was slower before the flood, would the bone of a prediluvian 900-year-old appear different from the bone of a modern 90-year-old?

    Compare the skeleton of a dog that died of old age at 20 with the skeleton of a man that died of old age at 90.

    ReplyDelete
  38. THE ATHEIST MISSIONARY SAID:

    "steve, expecting an academic response to 'the curse' is like expecting an academic response to the suggestion that there are fairies in my garden. Both assertions are gibberish and devoid of even a scintilla of evidence."

    i) That's an argument from analogy minus the argument.

    You use rationalistic rhetoric as a substitute for rational argument. There's nothing behind the pose.

    ii) There's no "scientific" evidence for the existence of abstract objects like numbers or possible worlds. Which doesn't mean there's no such thing.

    iii) I used to walk my dog to a local park. That was years ago, before she died, and I moved away. I have no "scientific" evidence that I used to walk my dog to a local park. Just my memory of doing so on numerous occasions. Should I disbelieve that event in the absence of "scientific" evidence?

    ReplyDelete
  39. TAM,

    You don't have the intellectual right to bring the 'God of the gaps' argument up with out engaging the refutation of it that has been done by ID theorists. See this key book before spouting out tired objections, it is a comprehensive source for arguments against ID:

    http://www.amazon.com/exec/obidos/ASIN/0830823751/qid=1089415677/sr=2-2/ref=sr_2_2/104-7208934-4273535

    Until you can engage with these arguments you are just shaming yourself by your ignorance of where the debate actually is and thereby discrediting your atheism.

    ReplyDelete
  40. TAm, also see this book by an atheist,

    http://www.amazon.com/Seeking-God-Science-Atheist-Intelligent/dp/1551118637/ref=sr_1_1?ie=UTF8&s=books&qid=1296426670&sr=1-1

    ReplyDelete
  41. TAM,

    you seem to have gone rather quiet. But if you are still listening, chapters 30 & 31 in the book I linked to in my earlier comment specifically address the 'God of the gaps' charge.

    If you ever bring up that charge again without engaging those answers, then it will be even clearer to everyone that you are not interested in truth.

    ReplyDelete
  42. Halo, thanks for recommending Dembski's book. I have been remiss in not reading that one and just ordered it. Thor bless you, TAM.

    ReplyDelete