April 30, 2007

Appearance of Design: Intuition or Illusion?

A couple of years ago I happened to catch a musical performance on Fox News. One of the general assignment reporters, Kelly Wright, was sharing a Christian song that he had written. It was called "I Believe," and its message was captured in the very first verse.

Whenever I see a newborn baby cry
Or see the birds flying high in the sky
That lets me know there's a God somewhere

While this is hardly a convincing apologetic for the existence of God, it does harbor an extremely important point. The vast majority of people believe in some sort of Supreme Being. If you ask them why this is so, you will hear a very common answer. To the average man, it is just a matter of common sense: "Look around you; look at the world; look at the beauty and wonder of life; it all had to come from somewhere!"

Life is remarkable and complex, and the more we learn the more amazing it all becomes. The default reaction is to be captivated by it – simply note any child's wonder on a visit to the zoo or a peer into the microscope. People just seem to have this notion that life is special, and the impression of intentionality and design presses hard upon them. For many, to insist that life is a fluke of nature is as absurd as trying to convince them that Mount Rushmore was carved by wind and rain.

This is not merely an emotional response to nature, but an inference from experience as well. The only experience we have of functional complexity originates from the minds and hands of intelligent designers, like humans. It is the same principle that NASA would use to infer the existence of alien life if a mere bolt were found on Mars, and it is the underlying assumption of SETI as they look for extraterrestrial radio signals containing even simple patterns.

Such ideas about life had been the bane of atheism for the better part of history until Darwinian theory arrived to exorcise these intuitions from our consciousness. Prior to Darwin, there were various speculative theories about the origin of life, like spontaneous generation, but they had to be satisfied with being classed more as philosophy than science. Darwin gave atheism the intellectual respectability that it had long sought. One of Darwinian evolution's chief apologists, Richard Dawkins, said it well in his book, The Blind Watchmaker.

An atheist before Darwin could have said, following [David] Hume: 'I have no explanation for complex biological design. All I know is that God isn't a good explanation, so we must wait and hope that somebody comes up with a better one.' I can't help feeling that such a position, though logically sound, would have left one feeling pretty unsatisfied, and that although atheism might have been logically tenable before Darwin, Darwin made it possible to be an intellectually fulfilled atheist.

Dawkins implies that biological design begs for an explanation. He's just averse to permitting God to serve as that explanation. But unless some alternative explanation can be offered, the intuition that complex order is best explained by a designer – the essence of Intelligent Design – stands unmolested. If I discover in the morning that my fresh-cut wood has been mysteriously stacked by my shed, then I would certainly be justified in thinking that some benevolent person has intentionally done the deed. Perhaps I would be mistaken, and it is in reality the work of a tornado, but until that case can be made I would be in my rights to stick with my initial assumption.

When Richard Dawkins tells us in The Blind Watchmaker that "biology is the study of complicated things that give the appearance of having been designed for a purpose," he outright admits to the default impression of design. However, he then goes on to explain why this is only a false impression, and that the order and purpose found in nature can actually be explained by evolutionary processes.

It may theoretically be the case that genetic variation and natural selection are the true authors of biology, but that is the alternative explanation offered in answer to the mystery of life. The theory of evolution has prevailed long enough that its supporters now believe it to be the natural and default victor. It may indeed be the reigning paradigm, but with each generation it must labor anew to suppress our intuitions. And this is why, in spite of all the academic and media hype, the purely random and materialist version of the theory continues to be rejected by the majority of the population.

I would propose, then, that the defeat of evolution would put design back onto center stage. Intelligent Design advocates are often criticized for trafficking in the flaws of evolutionary theory rather than offering positive evidence for design. But a critique of evolution is a case for Intelligent Design. As Dawkins admits, nature appears to be "designed for a purpose," and "design" implies a designer of some intelligence. If evolutionary theory fails at making the case that this appearance is merely an illusion, then we are justified in taking the appearance of design at face value. Intelligent Design lies just beneath the waxy veneer of evolution. It only remains to be seen what can truly be scratched off where there is liberty to do so.

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April 25, 2007

Cosmological vs. Biological Evolution

I just listened to a short radio debate between Eugenie Scott, director of the National Center for Science Education, and Hugh Ross, president of Reasons to Believe. The focus of the debate was evolution. Of course, their differences were numerous, since Eugenie is a notorious advocate for evolution, and Hugh is a well-traveled champion of various flavors of design arguments.

In the closing minutes, the two of them shared their agreement over the idea of an old universe and that galaxies, stars, and planets had formed by way of physical forces, even while they differed over the origin of biological life. Eugenie made a point of including cosmological history in her overall definition of "evolution," and one of her final remarks rested upon her liberal usage of the term. Her parting challenge to Hugh was this: "If the physical universe can evolve, why can't the biological universe?"

Now, Hugh would probably be okay with the idea that God had trumped the "natural" order of things and shaped our solar system just exactly how, when, and where He wanted it. In fact, I sometimes think that Hugh is implying this when he labors the point that our own Sun, Earth, and planetary system are exceptionally unique in their composition and arrangement. However, had Hugh been able to respond to this he probably would have pointed out the principle difference between cosmological and biological "evolution."

The origin of the universe may be a profound mystery, but the formation of galaxies and stars within this universe depend upon established laws of physics intrinsic to it. Of course, gravity is a key player in the cosmic drama, and it is a tangible force that we personally experience and can measure and test. Based on our calculations, we can predict what might be expected of galaxy and star formation, lifespan, and death, and when observing the universe we find confirmation of our understanding. The fact that light travels at a finite speed allows us to see the universe as it was at various ages, according to the distances we observe. We have, in effect, a very complete cosmological "fossil record."

So, in cosmology, there are known laws that deterministically act upon matter to shape it into certain kinds of forms, from simple to complex elements and objects. It is not a problem to imagine that God has used such secondary causes to shape our world. Even if God did not specially create our star and planet, it would appear that the forces He has ordained would yield things like them, just as we now observe other stars and planets forming. Perhaps it might be argued that there is not enough time and matter out there to yield by pure chance the very special life-sustaining attributes that our planetary system exhibits, but there are at least adequate materials and mechanisms to grant such opportunities.

Contrast this with biological evolution, which says that simple chemistry yielded life, and that simple life progressively underwent change to become complex life.

In chemistry, there are no gravity-like laws that will take chemicals lying about and form cells out of them. Even if you poured out all the complex molecules of which a simple prokaryotic cell consists they would still not self-assemble in a deterministic way. Indeed, it has been challenging enough to identify processes by which even the simplest molecules of life are formed. And it is not enough to simply propose that the right existing elements be available upon which chance might work its magic. There must be valid chemical pathways that obey the laws of physics, which can take elements through the necessary stages to produce target molecules. This is the world of roadblocks and rabbit trails in which origin-of-life researchers live.

Mainstream evolutionary theory is in slightly better shape. It at least proposes a process by which life advances. Unfortunately, that process involves, at its core, a very un-predictable and un-orderly element: mutation. These random corruptions and process failures are an exception to the functional rule of the cell, which is an otherwise law-abiding citizen. Evolution is ultimately dependent upon chance, along with the assumption that increased complexity is the preferential direction for natural selection to take. Contrary to what sci-fi movies might suggest, you cannot drop a mutagen into a vat of bacteria and yield a superbug like you can drop an apple and watch it fall. It may be argued that these random mutations are simply an indirect and roundabout process nonetheless, but that is the very questionable assertion on which the debate hangs.

Chance is a far different creature than deterministic physical law, and therein lies the difference between cosmological and biological evolution. This difference, and the chance/probability issues, have even led some to look for more common ground between the two. As Hugh Ross pointed out in his parting statement, prestigious scientists, like those at the Santa Fe Institute, have begun to propose an undiscovered law of self-organization to support the idea that the appearance of life is as inevitable as the gravitational collapse of matter into stars. If that were ever proved, then we'd certainly have a new topic to debate, but for the committed materialist it would only add one more incredibly odd and fortuitous law to the heap already begging for explanation.

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April 18, 2007

Punc Eq: Hide and Seek in the Fossil Record

"Geology assuredly does not reveal any such finely-graduated organic chain; and this, perhaps, is the most obvious and serious objection which can be urged against the theory. The explanation lies, as I believe, in the extreme imperfection of the geological record."
Charles Darwin, Origin of Species.

The prediction of a mounting inventory of transitional fossils was first made by Charles Darwin, who was well aware of the inadequacy of the existing fossil record to prove his theory of evolution. The optimistic task of fleshing out that fossil record was the prime directive for like-minded paleontologists for more than a century afterward. But by the second half of the 20th century it became increasingly clear that the paucity of fossil intermediates was not primarily due to the fragmentary nature of the fossil record (indeed, it was quite adequate in a variety of places); rather, it was reflective of the way that life itself had progressed.

It was after this disappointment of Darwin's largely failed prediction that the theory of Punctuated Equilibrium (courtesy of Stephen J. Gould and Niles Eldridge) was erected. This theory (PE) began with the admission that the fossil record is characterized by long periods of little or no change to species punctuated by the dramatic and sudden emergence of new species. It then added the rationale that the actual work of evolution must typically occur rapidly in isolated population groups, all this being too quick and geographically confined to grant much chance at fossil preservation.

Originally, some were skittish about the theory, because it was the first formal and tacit professional admission that the fossil record had failed to yield the hoped for intermediates, which was seen to lend aid and comfort to creationists. Even though there are notable dissenters to the theory, like Richard Dawkins and Daniel Dennett, it is now largely accepted in some form by supporters of evolution, and is regularly employed as a rebuttal to those filing a grievance against the fossil record.

As a reply, PE is primarily an explanatory device to fill a void, not a description of a proven phenomenon. PE can never be leveraged as evidence for evolution, since claiming PE is merely putting a name to the absence of evidence and adding a companion story. However, that does not stop the theory from being rhetorical genius: "Sure there are few intermediates. Don't be naïve; that's not how evolution works. I should be surprised if you did find them in abundance!" Evolutionists will simply have to bear with those of us who are skeptical of such a reply.

Now, I'm not suggesting there is no story to go behind PE. As I've said, it relates to the supposed accelerated evolution of isolated populations, which are then released into the larger domain where they might have a chance to flourish and be captured in the fossil record. This may have a certain plausibility to it, but, unfortunately, this narrative behind the theory is itself highly problematic.

Let us now look at some of the problems inherent in the "punctuation" scenario.

1) The smaller populations would also mean fewer creatures to yield mutations, beneficial or otherwise. Consequently, you would not expect increased evolutionary opportunities in such isolated groups. Even if the smaller demographics would somehow spread the new genes more quickly, this may be a no better scenario in comparison to the increased odds afforded by a more abundant mainstream population.

2) Evolutionary change begins with fortuitous mutations upon which "natural selection" may act. Isolated populations and environmental pressures do not mean increased rates of mutation, beneficial mutations, or "beneficial" mutations in the direction that would make a difference for a given creature within its given environment (e.g., a mole doesn't need wings and a tree climber doesn't need gills). Evolutionists often speak of the environment and new ecological niches as though they invite certain mutations. This is fallacious language. Need does not cause any random event to occur with a greater frequency or to yield the desired result at any higher rate; it could only cause a fortuitous thing to be preserved if it did happen to occur. For example, my urgent need to get to work on time will not cause the traffic lights to change any faster. And if I need a 4-of-a-kind to win a poker hand it will not increase the odds that I will draw one; but if I happen to be dealt 3 kings you can bet I won't choose any of those for my discard.

3) Even if it is somehow demonstrated that such isolated populations undergo an increased rate of mutation, then this proportionally increases the chances of detrimental mutations, which are vastly more common. And since it is said that mutations are better preserved in limited populations, then this means that there is an increased chance of tainting the entire genetic stock. The same "inbreeding" that is supposed to afford a beneficial mutation the chance to catch hold in the population is perhaps more likely to take down the entire group.

4) On a related note, the inbreeding of smaller populations actually results in genetic erosion, which is just as likely to lead to extinction due to loss of the genetic diversity that permits a species to survive environmental changes. The liability of population bottlenecks such as these has actually been observed and recorded (see here, here, and here for examples).

5) Quite often, the "punctuations" in the fossil record involve a broad spectrum of plants and animals that would not even be related by ecosystem, e.g., air, land, deep water, shallow water, etc. In this case, are we to assume that numerous isolated populations were all busily working in tandem and then were at once released onto the world stage? The biggest single example of this is the Cambrian Explosion, where nearly every phylum (major body plan) suddenly appeared in the fossil record after a long reign of nothing more complex than algae, sponges, and sea cucumbers. And to make matters worse, the Cambrian fauna was primarily warm-loving, but the period immediately preceding it was icy cold, from equator to pole, which doesn't lend much ground for breeding a whole biota of tropical species.

6) The hundreds of millions of years of geological history are often appealed to as grounds for optimism toward what chance can accomplish. But if real evolution can only happen in these periodic, isolated venues, which are interspersed with long spans of stasis, then this dramatically reduces the timeframe in which chance can do its work.

7) Since each of the millions of species would have had to undergo numerous of these "punctuation" surges to reach its present level of complexity, this means that such PE laboratories would need to be occurring at countless times and places. There should then be enough separate sites that we might hope to find at least one such incubator in the geological strata. PE should be, in principle, if not in all likelihood, an empirically verifiable theory if true.

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April 11, 2007

Evolution's Credibility Problem (part 3)

(Part 3 in a 3 part series)

We cannot just magically say that a mutation happens to produce the code for a new protein. The mutation must happen somewhere. If it happens over the top of an existing gene, then you've lost your original gene. And no matter how impressive the new gene sequence is, if the old sequence was important you may have just killed your organism. This means that the new gene must either supersede unused gene material (assuming such a thing exists), appear within an appended section of DNA, or be an improvement in line with the gene it is replacing. All three reduce the odds of a good mutation's survival, and the latter constraint would limit the scope of novelty.

Additionally, the mutation must either create or be contained within its proper domain. This is where it gets too complicated to continue describing things in detail, but suffice it to say that a gene must have certain controlling sequences in place for it to be effectively translated. For instance, there are start and stop codons, which define the boundaries of the gene. Within this there are things like promoters and ribosomal binding sequences to be considered. And even the best gene instruction is useless unless it has the proper signal sequence defined at its start to act as a sort of mailing address so that the machinery of the cell can know where the resulting protein is to be shuttled and deployed.

So, a workable mutation not only must result in sensible coding for the protein, it must include all of the logistical elements as well. If it does not produce these or happen in a way to make use of those which exist, then it is worthless. Worse, the mutation could easily manage to overlap these controlling sequences in such a way that it not only destroys an existing gene, but also could damage a gene next door if the overlap crosses the domain boundary.

Another consideration is based on the stunning recent discovery that many genes actually overlap by frame shifting of nucleotides or by inverse coding (up to 6 possible genes could be theoretically coded in the same physical space). This means that a change to even one nucleotide in the overlapping region could damage more than one gene. Risking damage to such a code base is one thing, but producing such a thing in the first place is a whole new dimension of incredible. To come close to understanding what I mean, simply imagine creating a palindrome more than 100 letters long (which is grammatically correct), even by design! Evolutionists would have us believe that this has happened countless times by mere chance.

Something else that I would point out: when we are dealing with creatures that sexually reproduce, a favorable mutation in one of the many cells of the organism (e.g., humans have trillions) is meaningless in evolutionary terms. This is because only germ cells are passed on to the next generation. Only mutations that happen in the few eggs or sperm that result in offspring are even candidates for evolution's "descent and natural selection." This means that the higher-order creatures that sexually reproduce, have fewer offspring, and longer generation cycle times, should theoretically evolve slower. But guess what: the quiet reign of single-cell organisms, which exist in vast quantities and reproduce fast and furiously, supposedly lasted more than 2 billion years; whereas the entire history of the relatively slower, fewer, and more diverse plant and animal kingdoms has occupied only a quarter of that time. And humans, some of the slowest breeders of all, appeared in a geological flash.

But back to my lactose-handling enzyme. Even this conceptually simple protein adaptation is far more complex than I suggest. In reality, beta-galactosidase consists of 1023 amino acids and actually functions in a larger structure composed of 4 of these proteins fit together. There are very few simple jobs in the cell. The protein "machines" to do the work are often quite complex, sometimes involving numerous independently designed proteins working in cooperation where the absence or poor design of even one would completely cripple the entire machine. And the machines generally require separate helper and regulating proteins to allow them to either do any work at all or to suppress them when they are not needed.

In the case of the relatively simple beta-galactosidase, it needs at least two other proteins: a permease that permits lactose entry into the cell (not just any 'ole thing is allowed in or out), and a repressor that works to inhibit the production of beta-galactosidase when there is no lactose in the neighborhood (there's no advantage in wasting precious resources). To further complicate things, each of these three components is found in the DNA in sequential order and is packaged together as a single unit, called an "operon."

Aspects of the cell are much like a factory, and just like in a real factory no single machine does much work in isolation. For example, in the case of the bacterial flagellum, a microscopic rotary motor, there are over 40 unique proteins that are involved in its architecture, and many more that are involved in its assembly and operation. As complex as individual proteins may be, establishing their place in the economy of the cell adds greatly to this complexity and cannot be overlooked. All of biology is characterized by interdependent systems — it is the norm.

In summary, the "small," incremental steps proposed by evolutionary theorists are astonishingly non-trivial and, in practice, can be as interdependent at the molecular level as a bat's various features are at the higher morphological level. What I describe is only the beginning of the many incredible things in the world of biology that evolution claims to explain. The more we learn and the more deeply we look at nature — into the microscopic world that Darwin could not have imagined — the more numerous and profound the required work of evolution seems to become. As I've said elsewhere, "Evolution gives fat chance a full time job."

Is there no room, then, for grace toward those who are unconvinced by the evolutionary story? Skeptics should be able to reserve the right to exercise the same principle of credulity that evolutionists themselves apply elsewhere. There is no denying that circumstantial evidence exists for the theory, but the explanatory work that evolutionists are seeking to do with it needs a mighty big engine to push this load over the hill of plausibility. And the fact that the theory itself is immune to reconsideration, in spite of the constantly pounding waves of unexpected and complex new biological discoveries, only fuels suspicion that there is something more than objective science behind it.

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April 10, 2007

Evolution's Credibility Problem (part 2)

(Part 2 in a 3 part series)

At this point I could mention the vast range of astonishingly complex things that evolution is said to have delivered (e.g., sentient life, metamorphosis, sexual reproduction, symbiosis, convergence, molecular machines), but none of these things is really much more incredible than the sub-cellular biochemical changes on which they each depend. Since ignorance is the chief ally of credulity, let me begin with a short lesson in cellular biology.

Nearly every structure in the cell and every chemical reaction that it spawns is dependent upon one or more large molecules called "proteins" (proteins facilitating chemical reactions are called "enzymes"). These molecules are composed of chains of smaller amino acid molecules (out of a possible choice of 20 amino acids), which are folded into various functional arrangements. Only a miniscule number of all possible arrangements of amino acid chains could serve a functional purpose in organisms. The arrangement of the final protein is dependent upon the position of the individual amino acids in the chain, since the right ones need to be in place to provide the necessary cross-linkages in the folds, as well as to result in the right group of chemicals being positioned together to form reaction sites. The final form is much like a custom crafted tool that is designed for a certain task.
SIDEBAR - Most proteins contains at least 100 amino acids. Given that there are 20 possible amino acids for each position within the protein chain, the total possible combinations is 20^100. That works out to a number close to 1 with 130 zeros after it. By comparison, the number of atoms in the entire universe is only around 10^80 (1 with 80 zeros). The largest proteins contain more than 2000 amino acids.
Amino acids are assembled into these important sequences by organelles called ribosomes. How do the ribosomes know what arrangements of amino acids to link together in order to make a desirable protein? They work off of a template provided to them by messenger RNA molecules (mRNA). So, how does mRNA arrive at its templates? It gets them by transcribing them from the DNA library. The buck stops at the DNA.

DNA is an unfathomably long double-helix shaped molecular ribbon whose primary job is to store blueprints for proteins. The design instruction for every protein the organism makes is found in some subsection of the DNA. These instructional units are called genes, and they have been likened to a language, with each "letter" representing an amino acid. Each gene would then be informationally equivalent to anything from a long sentence to a page of text.

So, how does this relate to evolution? For an organism to change form or acquire some new function, from the largest to smallest scale, it will require one or more new or altered proteins to do the trick. And since protein design is dependent upon the DNA, then DNA gene sequences must be either added or modified to pull this off. Since there is no established mechanism to introduce such changes evolution is dependent upon chance corruptions or copy mistakes (mutations) to deliver these "enhancements."

Mutations are not very common occurrences, since the cell contains a host of attendant proteins whose jobs are to proofread copy results, repair incorrect gene sequences, and reconnect broken strands of DNA. However, the occasional error does happen. This is the heart and soul of the biological change upon which natural selection is said to do its work: weeding the bad changes from the good, and favoring the better designs over the merely adequate existing designs. The problem now for evolution is to come up with beneficial mutations, but even evolutionists will admit that it is far more probable that a mutation be deleterious than desirable. Establishing exactly how improbable is the playground of heroic denial.

To be honest, it is not a precise statistical problem because there are some flexibilities and things as yet unknown in the biochemistry of the cell. However, there is enough that is understood to paint a very black picture for evolutionary probabilities. Let us take as an example a fairly "simple" problem that one bacterium supposedly faced in its evolutionary march toward complexity.

E. coli's primary food source, as with most organisms, is glucose. At some point in its history it would have encountered lactose (milk sugar) and would be at an advantage if it were able to process this, especially when glucose was not available. For this trick it would need an enzyme such as beta-galactosidase (which it does indeed employ) in order to convert lactose into glucose for its direct use. For now, let us assume that evolution needs just this one thing to make a big difference in this one organism. What, then, would it take to get such a thing?

Remember, in order to construct a protein we need a gene to describe it. This means that some mutation(s) must occur to arrange a stretch of DNA nucleotides into the necessary blueprint for beta-galactosidase, or something like it. Just to be generous, let's say that it is possible to make such a protein out of just 100 amino acids. So, how many possible arrangements of the amino acids could make something to do the trick? Just one? One hundred? One million? Let's be generous and say that one trillion trillion different arrangements (one with 24 zeros after it) could make a useful protein.

The problem is that compared with the number of possible combinations for the 20 amino acids in 100 various positions, this still means that there is not enough time in all of cosmic history to arrive at one of our arrangements, even if we convert every atom in the universe into copies of genes and randomly rearrange their sequences once per second! And the issues only begin here.

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April 07, 2007

Evolution's Credibility Problem (part 1)

(Part 1 in a 3 part series)

"The extreme rarity of transitional forms in the fossil record persists as the trade secret of paleontology — we fancy ourselves as the only true students of life’s history, yet to preserve our favoured account of evolution by natural selection we view our data as so bad that we never see the very process we profess to study."
Gould, Stephen J., "Evolution's erratic pace", Natural History, vol. 86, May, 1977

"No wonder paleontologists shied away from evolution for so long. It never seemed to happen. Assiduous collecting up cliff faces yields zigzags, minor oscillations, and the very occasional slight accumulation of change--over millions of years, at a rate too slow to account for all the prodigious change that has occurred in evolutionary history. When we do see the introduction of evolutionary novelty, it usually shows up with a bang, and often with no firm evidence that the fossils did not evolve elsewhere! Evolution cannot forever be going on somewhere else. Yet that's how the fossil record has struck many a forlorn paleontologist looking to learn something about evolution."
Eldredge, Niles, Reinventing Darwin, 1995

"To this day, excuses for the incompleteness of the fossil record, as in the fable of the emperor's clothes, overshadow the inescapable: The expression of novelty in nature arises suddenly."
Schwartz, Jeffrey H., "Adaption and Evolution." (Book Review). History & Philosophy of the Life Sciences, 2001, Vol. 23 Issue 3/4

"Given the fact of evolution, one would expect the fossils to document a gradual steady change from ancestral forms to the descendants. But this is not what the paleontologist finds. Instead, he or she finds gaps in just about every phyletic series."
Mayr, Ernst, What Evolution Is, 2001

Critics of evolutionary theory often point to the inadequacy of the fossil record to support Darwin's claim that life has been one slow progression from a common ancestor to the diverse species we witness today. The above quotes by supporters of evolution, along with many others that could be employed, make it abundantly clear that this criticism is no idle claim. For whatever reason, the fossil record continues to offer a paucity of support for the Darwinian notion of gradual change over time. While it might theoretically still be true, this is not the place to which one must look for a primary defense of the idea.

Apparent transitional fossils — the Holy Grail of evolution — are few and far between, and the geological strata is characterized by sudden appearance of new forms followed by long periods of limited diversity within those forms (i.e., stasis). This leads one to wonder if the transitionals are elusive by nature (as Gould argued) or if they are scarce because there were no such transitions.

If one were committed to the evolutionary hypothesis, and were guided by the fossil evidence alone, then it would seem reasonable to consider the possibility that biological change did not progress in a small stepwise fashion, but instead made great leaps forward ("saltations") at key points in the history of earth. This is the "hopeful monster" scenario advanced by Berkeley geneticist Richard Goldschmidt, which received only ridicule from his peers.

Why, though, should the consideration be so foreign to evolutionary theorists that life has bridged the great functional gaps between species all in single great leaps? Isn't the evidence pointing here, and aren't scientists concerned to follow the evidence wherever it leads? Isn't saltationism even a conceptual possibility? What is the principled objection to such an idea that keeps the theory trained primarily on the gradualistic model?

I submit that it is a matter of credulity.

To accept that the numerous and unique attributes that make up a newly appeared species, genus, family, etc. can come together at once to produce such a novelty is simply beyond the ability for even the most optimistic evolutionist to believe. For example, the bat appears suddenly in the fossil record, essentially in its modern form, complete with echolocation capability, yet no one would presume to suggest that the accompanying bone length and density adjustments, skin arrangement, cardiovascular alterations, and echolocation system all came together in one freak confluence of fortuitous mutations. That is too absurd even to imagine.

Additionally, the theory that the first organism to appear on earth was a single celled creature, like bacteria, has fallen out of favor in modern times. It is now assumed that there must have been some cascading series of "proto-cells" leading up to our ultimate cellular ancestor. And why is this assumed, in spite of the lack of geological or experimental evidence to support the idea? Because now that we have come to grasp the astonishing complexity of the cell it is simply too incredible to believe that it has appeared all at once.

The ironic thing is that critics of evolutionary theory have actually been accused of a "failure of imagination." In explanation of living organisms or their biochemical systems, which are too complex and interdependent to have come about in a stepwise fashion, evolutionists often appeal to imaginative scenarios. Rather than producing fossil intermediates and reproducible chemical pathways, which might settle the question, they offer just-so stories instead. However, an abstract theoretical framework is no substitute for empirical verification, and cannot be considered more than a hypothesis until such verification is forthcoming.

But if incredulity is a valid reproach to an idea, then why can we not also apply it to the supposed smaller steps of the gradualistic theory? Is the theory automatically plausible simply because it is alleged to occur in smaller increments? Are critics so irrational if they fail to be convinced by the evolutionary story even in this form? As it turns out, Intelligent Design (ID) theorists make the point that 1) the "small" steps are not all that trivial and 2) that small steps just won't get you where you need to go in most cases.

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