So much for signs of Mind. Where are we to look for signs of Purpose? Before 1859, the answer would have been obvious: in the marvelous adaptation of life to its environment. Charles Darwin, by the publication of The Origin of Species, presented us with natural selection as a patient process by which such marvels of “design” could come about, without the intervening purpose of a Designer being at work to bring them into being. At a stroke, one of the most powerful and seemingly convincing arguments for belief in God had been found to be fatally flawed. Darwin had done what Hume and Kant with their philosophical arguments had failed to achieve, abolishing the time-honored form of the argument from design by exhibiting an apparently adequate alternative explanation.

Since then, two important developments have taken place. One is the realization in the late 1920s that the universe itself has had a history and that notions of evolving complexity apply not only to life on Earth, but to the whole physical cosmos. The other is the acknowledgement that when we take this cosmic history into our reckoning, evolution by itself is not sufficient to account for the fruitfulness of the world. Let me explain.

A convenient slogan-encapsulation of the idea of evolution is to speak of it as resulting from the interplay of chance and necessity. “Chance” stands for the particular contingencies of historical happening. This particular cosmic ripple led to the subsequent condensation of this particular group of galaxies; this particular genetic mutation turned the stream of life in this particular direction rather than another. “Necessity” stands for the lawfully regular environment in which evolution takes place. Without a law of gravity, galaxies would not condense; without reasonably reliable genetic transmission, species would not be established. What we have come to understand is that if this process is to be fruitful on a cosmic scale, then necessity has to take a very specific, carefully prescribed form. Any old world will not do. Most universes that we can imagine would prove boring and sterile in their development, however long their history were to be subjected to the interplay of chance with their specific form of lawful necessity. It is a particular kind of universe which alone is capable of producing systems of the complexity sufficient to sustain conscious life.

This insight, called the Anthropic Principle, has given rise to much discussion. [Polkinghorne cites John D. Barrow and Frank  J. Tipler, The Anthropic Cosmological Principle; John Leslie, Universes and his own Polkinghorne, Reason and Reality, chap. 6, and Beyond Science, chap. 6.] Is it no more than a simple tautology, saying that this universe which contains ourselves must be compatible with our having appeared within its history? For sure that must be so, but it is surprising—and many of us think significant—that this requirement places so tight a constraint on the physical fabric of our world. Although we know by direct experience this universe alone, there are many other possible worlds that we can visit with our scientific imaginations, and almost all of them, we believe, would be infertile.

Sometimes the Anthropic Principle is also called the Goldilocks Principle: if all of the physical conditions were not “just right,” there could be no life whatsoever in the universe (source: http://home.netcom.com/~swansont_2/goldilocks.jpg)

John Leslie, who has given a detailed account of the many processes that depend on the precise character of physical law for their ultimately life-generating effects, has also given a careful discussion of what conclusions we might draw from the Anthropic Principle. [Leslie summarizes his position at here.] We are in a realm of discourse where such conclusions depend on the judgment that we have attained a deeper and more comprehensive understanding, rather than that we have deduced a logically unassailable consequence. Leslie believes that it is no more rational to think that no explanation is required of fine anthropic coincidences than it would be to say that my fishing apparatus can accept a fish only exactly 23.2576 inches long and, on casting the rod into the lake, I find that immediately I have a catch, which is simply my good luck -- and that’s all there is to say about it. The end of the matter for Leslie is: “My argument has been that the fine tuning is evidence, genuine evidence, of the following fact: that God is real, and/or there are many and varied universes. And it could be tempting to call the fact an observed one. Observed indirectly, but observed none the less.” [Quoting Leslie, Universes, p. 198. The fishing example is on pp. 9-13 in the same book.] Either there is one world whose fruitful potential is the expression of divine purpose or there are many worlds, one of which just happens to be right for the evolution of life.

Those who wish to avoid any suggestion of a divine purpose manifested in the fruitful fine tuning of physical law will have to opt for the second of Leslie’s alternative explanations. [Here Polkinghorne has a note: “A theist could, of course, combine the two options, but personally I find that unappealing.”] There are a variety of ways in which one might conceive of the existence of such a portfolio of different universes, understood as domains in which different laws of nature are operating. The more plausible accounts will seek to make some appeal to scientific knowledge and will not just rely on the ad hoc assumption that there are a lot of separate worlds that just happen to exist.

Many-worlds quantum theory will not do the trick (even if one believed in it, which I do not), for its parallel worlds are simply ones in which quantum events have different specific outcomes and the basic laws of nature are common to them all. [Polkinghorne cites The Quantum World, pp. 67-68, and Alastair. Rae, Quantum Physics: Illusion or Reality?, chap. 6.] Modern ideas about symmetry breaking offer a little more scope. If there is a Grand Unified Theory of the fundamental forces of the universe, then the particular forces that we actually observe, and which are the concern of the Anthropic Principle, will have crystallized out from this highly symmetric ur-state very early in cosmic history, as expansion cooled the world below the relevant transition temperature. The precise details of this symmetry breaking, and the consequent precise force ratios resulting from it, are spontaneously generated through the amplification of tiny random fluctuations. This process need not be literally universal, and the cosmos may be split into vast domains in which different consequences have been realized. The universe observable by us might be a part of one such huge domain, and, of course, in our particular neck of the woods, the force ratios are “by chance” compatible with our evolution. This account is speculative, but motivated, and I am inclined to consider its possibility as far as it goes. That, however, is not very far. One still needs the right sort of Grand Unified Theory for all this to be feasible, and in that respect our universe is still very special compared to the totality of universes that we can imagine.

Moving up on the scale of bold speculation, one might evoke notions of quantum cosmology which suggest that universes of various kinds are continually appearing as a physical process called inflation blows up microworlds, which have bubbled up as quantum fluctuations in some universal substrate. [Here Polkinghorne has a note: “The quantum vacuum is an active medium owing to fluctuation effects.”] Proponents of this point of view are sometimes moved to describe our anthropic universe as being “a free lunch.” The phrase itself should trigger a cautious evaluation of the offer being made. The cost of this particular cosmic meal is the provision of quantum mechanics itself (a classical Newtonian world would be a perfectly coherent possibility, but a sterile one), and just the right quantum fields to fluctuate in order to produce first inflation and then all the necessary observed forces of nature. This idea is less well established scientifically than the domain option and, in any case, it does not really remove anthropic particularity, for the basic physical laws still have to take certain specific forms which are the necessary foundation of the proposed quantum cosmology.

Beyond this point, speculation becomes rapidly more rash and more desperate. Maybe, the laws of nature themselves fluctuate, so that a vast portfolio of conceivable, or (to us) inconceivable, worlds rise and fall in the relentless exploration of random possibility—occasional patches of transient and varied order in a sea of seething chaos. We have moved far beyond anything that could be called scientific in this exercise of prodigal conjecture. It is time to consider Leslie’s other alternative: that there is a divine purpose behind this fruitful universe, whose fifteen-billion-year history has turned a ball of energy into the home of saints and scientists, and that this purpose has been at work in just one world of consistent physical law (though maybe with domains of different expressions of that law).

Once again the theistic conclusion is not logically coercive, but it can claim serious consideration as an intellectually satisfying understanding of what would otherwise be unintelligible good fortune. It has certainly struck a number of authors in this way, including some who are innocent of any influence from a conventional religious agenda. [Polkinghorne cites two books by Paul Davies, God and the New Physics, and The Mind of God; Hugh Montefiore, The Probability of God; and his own Science and Creation, chaps. 1, 2; and 4.] Such a reading of the physical world as containing rumors of divine purpose, constitutes a new form of natural theology, to which the insight about intelligibility can also be added. This new natural theology differs from the old-style natural theology of Anselm and Aquinas by refraining from talking about “proofs” of God's existence and by being content with the more modest role of offering theistic belief as an insightful account of what is going on. It differs from the old-style natural theology of William Paley and others by basing its arguments not upon particular occurrences (the coming-to-be of the eye or of life itself), but on the character of the physical fabric of the world, which is the necessary ground for the possibility of any occurrence (it appeals to cosmic rationality and the anthropic form of the laws of nature). [For some historical comments on this approach to natural theology, see here.]

This shift of focus has two important consequences. The first is that the new-style natural theology in no way seeks to be a rival to scientific explanation but rather it aims to complement that explanation by setting it within a wider and more profound context of understanding. Science rejoices in the rational accessibility of the physical world and uses the laws of nature to explain particular occurrences in cosmic and terrestrial history, but it is unable of itself to offer any reason why these laws take the particular (anthropically fruitful) form that they do, or why we can discover them through mathematical insight. The second consequence of this shift from design through making to design built into the rational potentiality of the universe is that it answers a criticism of the old-style natural theology made so trenchantly by David Hume. He had asserted the unsatisfactoriness of treating God’s creative activity as the unseen analogue of visible human craft. The new natural theology is invulnerable to this charge of naive anthropomorphism, for the endowment of matter with anthropic potentiality has no human analogy. It is a creative act of a specially divine character.

“Création ex nihilo,” from Charles de Bouelles, Libellus de nihilo (1510). God “inspires” (breathes or blows into) the universe, creating it out of nothing (ex nihilo).

Looking Ahead

In the next excerpt, Polkinghorne turns his attention from physics and teleology to biology and theodicy. Look for it in a couple of weeks.

References and Credits

Excerpts from John Polkinghorne, Belief in God in an Age of Science (1998), copyright Yale University Press, are reproduced by permission of Yale University Press. We gratefully acknowledge their cooperation in bringing this material to our readers.

For further reading on the scientific, philosophical, and theological aspects of modern cosmology, see Hans Halvorson and Helge Kragh, “Cosmology and Theology,” in The Stanford Encyclopedia of Philosophy, ed. Edward N. Zalta (Winter 2011 Edition).

Editorial Policy

Most of the editing for these excerpts involves breaking longer paragraphs into multiple parts, altering the spelling and punctuation from British to American, removing the odd sentence or two—which I indicate by putting [SNIP] at the appropriate point(s)—and sometimes inserting annotations where warranted [also enclosed in square brackets] to provide background information. Polkinghorne uses footnotes a bit sparingly, and I usually find another way to include that information if it’s important for our readers.

Evidence from the Size of the Universe

We’ve already discussed the vastness of the universe earlier in this chapter. We noted that the most distant galaxies are over 10 billion light years away, indicating that the light left these galaxies over 10 billion years ago in order to reach us today. The straightforward interpretation of these data is that the universe must be at least 10 billion years old.

While some people have argued that perhaps these galaxies aren’t really that far away, all of the methods used to measure distance agree that galaxies are billions, not thousands, of light years away. Others have argued that perhaps the light moved much faster when it first left these galaxies, so that it could reach us in much less time than 10 billion years. But this idea conflicts with other data that we have. As described in Chapter 3, ample evidence supports the idea that physical processes such as quantum mechanics and electromagnetism function the same way in distant galaxies as they do on earth. Those physical processes depend on the speed of light and would look very different if the speed of light had changed. Instead, they look the same in distant galaxies as they do on earth, indicating that the speed of light has been constant over the history of the universe.

Evidence from the Moon and Planets

Studies of the Moon and planets also give evidence for great age. Geologists can use some of the same methods to measure the age of rocks on the Moon, Venus, and Mars as they use on Earth. That’s because the asteroid collisions, volcanoes, and erosion they observe on Earth also occur on the Moon and planets. Photos taken by spacecraft while orbiting Mars show channels and gullies on the planet’s surface. Similar channels on Earth are usually made by flowing water. Yet there is no liquid water on the surface of Mars right now.

What does this have to do with age? It is evidence that Mars was much different in the past than it is today. The atmosphere used to be much thicker and warmer, similar to Earth’s, but now it is much colder and thinner. This dramatic change in planet-wide climate took millions or billions of years. Thus the rocks testify that the planet Mars must be at least this old.

Evidence from the Orbits of Asteroids

The orbits of asteroids also show evidence of a long history. When an asteroid is discovered, its path through the sky shows its orbit around the Sun. Once astronomers know the orbit of an asteroid they can calculate its orbit in the past and into the future to see whether it will hit the earth. By calculating the orbits backward, astronomers have found several asteroids that converged at the same location several million years ago. Apparently two larger asteroids collided at this spot and shattered into the smaller asteroids we see today. If God had created asteroids just a few thousand years ago, why would he have put them in orbits that suggest a collision several million years ago? The evidence clearly points to a long history for asteroids.

Evidence from Meteorites

Radiometric dating is used to study rocks on Earth as well as rocks from elsewhere in the solar system. Studies have been done on the rocks that astronauts brought back from the Moon and on asteroids that have fallen to Earth. As with Earth rocks, scientists use multiple radioactive isotopes to cross-check age measurements. At least three different isotopes have been used to measure the age of Moon rocks, and at least five different radioactive isotopes have been used to measure the age of meteorites. The results all agree: the oldest Moon rocks and asteroids are 4.6 billion years old. This is our best measure of the age of the solar system as a whole. The universe itself must be at least this old.

Evidence from Star Clusters

Another important measure of age in the universe comes from star clusters. Because all stars in a star cluster form in the same nebula at about the same time, they all have about the same “birthday.” But they don’t all have the same lifespan. High-mass stars burn bright and fast like a “flash in the pan,” while low-mass stars burn slowly and steadily. Consider how this will look in a star cluster. A cluster starts with many stars with the same birthday but of all different masses. Over time the high-mass stars die off first, leaving behind the low-mass stars. This means that if many high-mass stars are present, the cluster must be young because they haven’t burned out yet. If most of the stars are low-mass, the cluster must be old. Careful studies of star clusters show that some clusters are younger and some are older, with the oldest ones having an age of about 12 billion years.

Multiple Lines of Evidence

The most distant galaxies, the planets and asteroids of our own solar system, and the oldest star clusters all are several billion years old. Astronomers have many different methods for measuring the age of various objects, and they all support ages of billions of years, not thousands. Even if the assumptions of one or two methods were faulty, it is highly unlikely that all of the methods would be affected. Like the geologists in the 1700s, astronomers today have found multiple lines of evidence against a young earth and young universe.

It may seem as though we are once again describing a conflict between science and theology. Scientific results that indicate great age do conflict with the Young-Earth Interpretation of Genesis 1 discussed in chapter 5. But remember that in chapters 5 and 6 we presented many other interpretations of Genesis 1; several of these are not in conflict with the great age found in the book of nature. In chapter 6 we also explained why we believe that the best biblical scholarship, quite independent of modern science, indicates that Genesis 1 was never meant to convey scientific information to the original audience. Its intent for the first listeners, and for us, is to teach the who and why of creation, not the how and when. Taken in this context, there is no conflict between Genesis 1 and the astronomical evidence for great age.

For background on related topics (like the reliability of historical science and interpretations of Genesis), see previous excerpts from this series.

Excerpt from Chapter 7 of Origins: Christian Perspectives on Creation, Evolution, and Intelligent Design (Grand Rapids, MI: Faith Alive Christian Resources), 2011. Reprinted with permission. To purchase a copy of the book or e-book, call 1-800-333-8300 or visit www.faithaliveresources.org.

Want a free copy of Origins?  For a limited time, donations of $50 or more will receive a  copy of the book! Plus, from now through April, your gift will be doubled thanks to a matching grant from a generous donor. You can learn more here.

As is the case in many fields, astronomers are trying to settle questions that the general public thinks little about, often because laypeople are still coming to grips with much more basic questions such as Did the universe appear—poof—all at once or did it evolve into its present state?

These are questions where science crosses into—and sometimes crosses swords with—religion. For many who take an anti-evolutionary stand as a matter of spiritual principle, the word evolution should not be applied to anything having to do with creation, cosmic or otherwise. Yet, if an evolving universe implies a beginning (and it does, for relativistic reasons), science has taken a tremendous leap toward rapprochement with Christian faith on the matter of creation. Traveling backward in time with their shrinking subject, cosmologists can only watch the cosmos disappear at the beginning, pointing to a universe that came out of nothing—a universe that wasn’t there.

No one need ask: “Were you there?” Chuck Steidel has tapped into nature’s own motion picture of past events, now showing in the present. Anyone who cares to view it can now see for himself what was and wasn’t there, at various stages of the deep past.

While other astronomers at first assumed that larger telescopes would be necessary before finding truly primeval galaxies, Steidel began finding dozens of them—and today, thousands of them. His method, called ultraviolet dropout, is based on the fact that intergalactic hydrogen gas absorbs the ultraviolet light of the most distant galaxies, causing them to disappear when seen through an ultraviolet filter. Steidel identified early galaxies that are present in pictures of the cosmos when viewed through red and green filters, but that aren’t there when viewed through an ultraviolet filter.

Visual evidence for a universe that isn’t there starts with the observation of galaxies that aren’t there.

“The way that people have looked for these in the past tended to be looking for particular, spectacular fireworks of stars going off all at once,” Steidel told me. He was only 32—a young-looking 32—and could have passed more easily as a student than as a professor as he talked with me in his Caltech office, surrounded by Hubble Deep Sky images. “So they were looking for relatively rare events, using narrow-band filters tuned to find an emission line that comes from hydrogen atoms. And you have to have the filter exactly tuned to that wavelength to see it.”

“And I’ve heard it’s like trying to find a needle in a haystack,” I offered.

“It’s much more difficult.”

“So rather than try to find something that stands out you’re trying to find something that drops out?”

“That’s correct. It’s a very simple technique, where we take pictures through different filters, very deep images of the sky with CCD detectors, and we take three filters, and we look for objects that are present through two of those filters, and they completely disappear in the third. And the reason they disappear is because they’re at a high redshift.”

The high redshift denotes greater distances—and earlier periods, because of the time required for light to reach us from those greater distances. These young galaxies contain young, hot stars, emitting strongly in the ultraviolet. However, ultraviolet radiation from the most distant galaxies is absorbed by a greater amount of intervening hydrogen gas along the way. Today, Steidel uses the 200-inch Hale Telescope at California’s Palomar Observatory to find these primeval galaxies with his ultraviolet dropout technique, then flies to the 10-meter Keck telescope in Hawaii to measure their redshift, which corresponds to their distance and time period.

And what do these galaxies look like?

“We actually think we’re seeing the central bulge regions of galaxies forming,” said Steidel, “that is, the round part in the middle of a spiral or an elliptical galaxy, where you expect all of the star formation to be happening in a relatively small region. And those parts of galaxies we see today are also the parts that we think are the oldest stars in those galaxies.”

“And you’re saying that modern galaxies have the oldest stars in the bulges, is that right?”

“That’s right …. It’s still somewhat controversial. But there isn’t any doubt that we’re finding a number of things that match fairly closely to the number that you would expect to find if you were looking at the progenitors of the present-day, bright galaxies.”

Steidel’s galaxy surveys have shown that galaxies were already arranged in clusters at that early time. But the individual, primeval galaxies lacked the characteristics of today’s spirals and ellipticals. More recently, Steidel has focused on a slightly later period, from about 10 to 12 billion years ago, when star formation appears to peak. If seeing is believing, then, as Steidel says, the universe “has absolutely changed with time.” His methods have helped astronomers identify populations of galaxies at various stages, where their differences from one to another are unmistakable.

In the years ahead, telescopes beyond our obfuscating atmosphere, like NASA’s James Webb Space Telescope (collecting six times as much light as the Hubble), may begin to give us glimpses of the “Dark Ages,” when the first galaxies began to form. As our improving technologies bring us closer to the beginning, they will lead people to ponder, once again, what happened before that. 

In my interviews with researchers, I usually bring up such crossover questions when the scientists or their studies naturally suggest them. But I worried that I’d crossed over too clumsily into this territory with Steidel when I asked him what he thought about a universe that appeared to come into being out of nothing.

He hesitated and said, “What happened before, you know, it’s …” and his voice trailed off. 

Finally I suggested: “Something must have happened before.”

“I think about that extremely rarely.”

Shoot, I’d gone too far, I thought.

But then he added: “On the other hand, I do have a very wide appreciation for whatever put things there—because it’s just the greatest thing to go out on the catwalk around the dome, in the middle of the night, and just look up there, or look at a picture of the Hubble Deep Field, and see all the things that are out there, and—you know— it’s a beautiful universe out there.”

Indeed, come to think of it, the way it all came together may be an even more impressive fact to ponder than the fact that at one time, that is, before time, the universe wasn’t there.

So, I’ve decided to try a slightly different approach for the next while—one that has these sorts of folks in mind. From time to time, you can still expect those more in-depth, technical articles, or perhaps a discussion of some new research that makes the popular press, or even an analysis of some new argument from the IDM or RTB. These will be breaks from the new routine, however. For the most part, we’re going to stick to the basics, much like you would if you took an introductory evolution course at a university. Don’t worry, though: this course doesn’t have any prerequisites! All that’s needed is a willingness to learn.

What you can expect

The goal of this course is straightforward: to provide evangelical Christians with a step-by-step introduction to the science of evolutionary biology.  This will provide benefits beyond just the joy of learning more about God’s wonderful creation. An understanding of the basic science of evolution is of great benefit for reflecting on its theological implications, since this reflection can then be done from a scientifically-informed perspective. From time to time we might comment briefly on some issues of theological interest (and suggest resources for those looking to explore those issues further), but for the most part, we’re going to focus on the science. For folks interested in the interaction between science and Christianity, I heartily recommend Ted Davis’ recent series as a fabulous introduction to the topic.

You can also expect a slow, patient pace. Since this course is intended for folks with little or no background in biology, we’re going to take our time to make sure no one gets left behind. This might be frustrating to folks who already know a fair bit about evolution. Hopefully even more knowledgeable readers will learn some new and interesting details along the way—but the goal will primarily be to help folks who are less well versed in evolution increase their understanding.

You can also expect a survey of many different areas that have some bearing on evolution. We’ll examine geology, paleontology, biogeography, genetics, and a host of other topics in order to provide a “big picture” overview. This broad-brush approach means that any given individual post will not necessarily be “convincing” to folks who have doubts about evolution. Think about assembling a large jigsaw puzzle: placing any individual piece, on its own, doesn’t convincingly demonstrate what the overall picture will show. This course will be like that. Each topic we cover will put a few pieces in place here and there, slowly building towards the final overall picture.

Since evolution is an active science, this process will also highlight where there are “missing pieces” that are still being sought by scientists. All of this is well and good, since the purpose of this course is not so much to convince anyone of the validity of evolutionary theory, but rather to inform readers about the nature and scope of evolution as a scientific theory in the present day. My goal is to provide readers with a basic understanding of what evolution is and how it works. Given that as the primary goal, if one finds the scope of the evidence ultimately convincing (or not) is somewhat beside the point. The intent here is to provide readers with information they can use to make their own, informed decision.

How you can help

First and foremost, you can help by spreading the word about this series to folks you think would be interested in learning more about evolution in a non-threatening environment. Secondly, you can help me by asking questions in the comments. One of the challenges of being a specialist is having the ability to put oneself in the shoes of someone just starting out. What might seem obvious to me may not seem obvious to you, and I hope you’ll feel that no question is too basic or too simplistic. If you’re wondering about something, it’s almost guaranteed that other folks are, too! So, please don’t be shy. I’ll do my best to answer questions in the comments, though I hope that some of our more skilled commenters will (respectfully!) help out here, as well. Finally, you can help by letting me know what broader areas of evolution you find confusing. I have my own ideas about what areas of evolution are commonly misunderstood, but I’d love to hear from readers about what areas they find difficult to understand. I’ll use this input to shape the topics I will cover as we go forward.

Getting started

In the next post in this course, we’ll dive into the course content by introducing two key areas: how scientific theories work in general, and how evolution in particular works as the current organizing theory of modern biology. 

Antibody fine-tuning

At this moment, millions of B cells are patrolling my spleen and lymph nodes, each sporting a different antibody on its surface. If a foreign molecule from the cold virus happens to stick to an antibody on a particular B cell, the cell can get “activated.”

Pathogens are like cockroaches. If you see one roach, you can bet there are many more lurking under cupboards and between walls. Just as one shoe won’t kill them all, one B cell can’t make enough antibodies to deal with an infection. Activation causes the B cell to reproduce, creating more and more B cells that can produce the same kind of antibody.

As is typical during cell division, most of the DNA in dividing B cells is copied with extremely high accuracy. But in the gene segments coding for the variable region of the antibody, mutations accumulate about a million times more often than normal. Why would this be? Isn’t the point of B cell replication to make more identical antibodies?

Almost. It turns out that these frequent random mutations contribute to optimize the antibody. A shopping story helps to illustrate. I was recently at the mall and found a fabulous pair of shoes on sale. Sadly they were out of my size, but it was such a good sale that I decided to buy the half-size down, figuring the shoes might stretch out a little and grow more comfortable with time. Bad idea! That great bargain turned out to be pretty expensive when I got blisters and never wore the shoes again. Clearly this was not an optimized choice.

Just because you can get your foot into a shoe does not mean it fits. Likewise, just because an antibody binds to an antigen does not mean the two are perfectly complementary. Descendents of the activated B cell have a mechanism to induce mutations so each one can make a slightly different version of the antibody. If one of the resulting B cells makes a better-fitting antibody than its kin, it will have a selective advantage and proliferate. The other cells will not become activated as often and will end up dying by apoptosis, a kind of cellular suicide. This mechanism of mutation and selection, called affinity maturation, produces a highly specific, strong interaction between the antigen and the antibody.

Antibody production and evolution both involve mutation and selection

I believe God is sovereign over all of creation, but I don’t imagine he is presently curing my cold by directly controlling the specific gene rearrangements and optimizing mutations in each of the millions of B cells in my body. Could he do so? Of course! But if that were the case, why bother making billions of antibodies in the first place? The evidence suggests that God has chosen to work through a random process, one which involves the routine creation and destruction of millions of cells that never get used. This is the ordinary means by which God maintains our health. The miracles of healing recorded in the Bible are miraculous precisely because they don’t occur by this normal, natural process.

In my last post, I stated that the generation of antibody diversity is an example in which God uses a “blind” system to sustain and preserve life. I then suggested a link to evolution by asking, “If God uses natural mechanisms that work over short time scales (less than a week) to evolve life-giving solutions to disease, could he also use a similarly elegant approach to create life over long periods of time?”

Some may argue that a small-scale process like antibody production isn’t comparable to the processes of mutation and natural selection that are supposed to have caused macro-evolution. Intelligent Design proponent Michael Behe, for example, accepts that all creatures (including humans) have a common ancestor, but he believes random mutations are not powerful enough to have brought about the diversity of life we see today. He argues that there is an “edge” of evolution: mutation can bring about drug resistance and other small-scale adaptations, but beyond a certain point it can’t really produce anything new.

Clearly, antibody production creates something new: the random recombining of whole gene segments generates highly specific, never-before-seen protein functionality within just a few days. The body can respond to any foreign entity, simply by sorting through billions of ready-made possibilities. Furthermore, a pretty-good solution can be made even better by generating many variations on a theme and sorting through these for the optimal antibody.

Evolution works by the same kinds of mechanisms, except the mutations occur in germ cells (which give rise to egg and sperm) rather than in B cells, and the sorting (selection) process occurs at the population level rather than the cellular level.

Though often neutral or destructive, mutations sometimes create new functionality

Most people are familiar with point mutations, in which a single DNA “letter,” or base, gets changed. However, mutations come in several other varieties. Short sequences of DNA can be inserted or deleted at random. Chunks of DNA can get cut out and inserted in the opposite direction. Individual genes or even whole chromosomes can get lost or duplicated. In rare cases, the entire genome can get duplicated!

The effect of a mutation principally depends on where it occurs, not on the size of the DNA segment affected. A large deletion occurring within a long stretch between two genes may do nothing at all. On the other hand, a single point mutation within a critical gene may cause a devastating disease. There is also a third possibility though: new functionality may emerge as a result of a mutation.

Let’s consider the protein hemoglobin, for example, which binds oxygen and transports it throughout the body in the blood. Hemoglobin is made from two pairs each of two amino acid chains, called α and β (blue and red in the figure at right). The corresponding genes that code for α and β have similar sequences to each other, and are believed to have arisen when an ancestral globin gene (still present in marine worms, insects, and some fish) duplicated and slowly changed over time. While the ancestral form can bind oxygen just fine, the four chains of hemoglobin cooperate to do so even better.

Both the α and β genes have undergone further duplications followed by smaller mutations. As expected, many of the resulting genes have become irreparably damaged by mutations, but they continue to exist in the genome as inert DNA “fossils.” Others, however, remain active and now perform specialized functions. For instance, one set of β genes binds more tightly to oxygen than the others; it becomes active only during development to ensure that the fetus gets enough oxygen from the mother’s bloodstream. A few months after birth, fetal hemoglobin turns off and the adult form turns on.

To summarize, mutations come in many forms (e.g. rearrangements, insertions, deletions, duplications) and can lead to good, bad, or neutral effects within an individual. B cells depend on random mutations to produce novel antibodies. A few are productive, but the vast majority of B cells die unused. Yet the entire process works for our good! In the same way, mutations in germ cells can lead to no effect, disease, or new and better solutions, as we saw in the hemoglobin example. These are the ordinary (but masterful!) means by which God creates and sustains life.

Editor's Note: For more on the evolution of the immune system, read Randy's Isaac's post "Complex Specified Information Without an Intelligent Source" at the ASA website.

My valiant helper, a small-sized tiger
Sleeps sweetly on my desk, by the computer,
Unaware that you insult his tribe.

Cats play with a mouse or
with a half-dead mole.
You are wrong, though: it’s not out of cruelty.
They simply like a thing that moves.

For, after all, we know that only consciousness
Can for a moment move into the Other,
Empathize with the pain and panic of a mouse.

And such as cats are, all of Nature is.
Indifferent, alas, to the good and the evil.
Quite a problem for us, I am afraid.

Natural history has its museums,
But why should our children learn about monsters,
An earth of snakes and reptiles for millions of years?

Nature devouring, nature devoured,
Butchery day and night smoking with blood.

And who created it? Was it the good Lord?

Yes, undoubtedly, they are innocent,
Spiders, mantises, sharks, pythons.

We are the only ones who say: cruelty.

Our consciousness and our conscience
Alone in the pale anthill of galaxies
Put their hope in a humane God.

Who cannot but feel and think,

Who is kindred to us by his warmth and movement,

For we are, as he told us, similar to Him.

Yet if it is so, then He takes pity
On every mauled mouse, every wounded bird.
Then the universe for him is like a Crucifixion.

Such is the outcome of your attack on the cat:
A theological, Augustinian grimace,
Which makes difficult our walking on this earth.

–Czeslaw Milosz,¹
 translated by the author and Robert Hass

The Problem

The poem above communicates in a very poignant and profound way the essence of the theological problem of death, pain, and suffering in the natural world—what has been referred to as “natural evil.” As we will see, it may also point to at least one aspect of a Christian response.

I have become convinced that one of the fundamental issues underlying much of the resistance of many Christians to an ancient, evolving creation is that of the problem of “natural evil.” “Natural evil” is also very often a primary focus of those who reject a personal and compassionate God, as it was for Darwin himself. The issue of theodicy thus seems not only to drive many people of Christian faith away from an acceptance of the conclusions of modern science, but also to drive members of the scientific community away from a serious consideration of the claims of the Christian faith. The topic is important, then not because its solution is central to the validity of the Christian faith, but because it often serves as an unnecessary stumbling block to a productive engagement of both science and faith.

The tension generated by our understanding of God’s character, as revealed in the Bible, and by the reality of the natural world around us has been the focus of much theological and philosophical debate within the Christian church since the first century. This article sets out to examine critically several of the proposed solutions to this problem, viewing them from the perspective of a geologist, paleontologist, and orthodox evangelical Christian.

The theological problem of death and pain emerges from the following propositional statements:

1. Scripture consistently declares the absolute goodness of God and the very goodness of his creation. Furthermore, Scripture declares God’s love and care for creation, and the glory and praise it returns to him.
2. Scripture also confesses a transcendent God who is omnipotent in power, yet immanent in creation as well. God’s creative activity is not described as being confined to some past event at the beginning of time, but as a present and continuing reality. God upholds creation in its being from moment to moment, and is creatively active in its history. This understanding of God’s relationship to creation has been well articulated by Jürgen Moltmann.²
3. In seeming conflict with these confessions of God’s character, we observe death, pain, and suffering as ubiquitous, even integral, aspects of the creation around us.

The apparent conflict between God’s goodness and the presence of pain and suffering is made especially acute when we consider the nonhuman creation.³ How can we accommodate the death and suffering of animals within a theology that declares both God’s omnipotence and goodness? C. S. Lewis forcefully puts the issue before us in his book The Problem of Pain:

The problem of animal suffering is appalling; not because the animals are so numerous ... but because the Christian explanation of human pain cannot be extended to animal pain. So far as we know beasts are incapable either of sin or virtue: therefore they can neither deserve pain nor be improved by it.⁴

Because the issue of animal pain so directly impacts our understanding of the goodness of creation, I will focus particularly on solutions to the problem as posed by Lewis.

How do we then reconcile the goodness of God who is immanent and active in his creation with the death, pain, and suffering we see embedded within it? There seem to be two basic alternative approaches to this dilemma.⁵

1. Natural evil can be attributed to something independent of God and acting against his will. This position threatens to limit God’s power and freedom.
2. Natural evil can be considered a part of God’s good purpose for creation, and either directly willed or permitted by him. Such a view would seem to bring into question God’s goodness and love for his creatures.

The tension between these alternatives—and efforts to avoid their negative theological consequences—surface in many of the proposed solutions to this problem.

In part 2, we start to look at some of the proposed solutions, beginning with the idea that a perfect creation was corrupted by a fall.

Notes

1. This poem was included in a collection of poems that was one of two works by Czeslaw Milosz mentioned in a review article by Michael Ignatieff, “The Art of Witness,” New York Review of Books (March 23, 1995). I thank Carol Regehr for bringing my attention to this work.
2. Moltmann refers to this aspect of God’s creative activity in history as “continuous creation.” Jürgen Moltmann, God in Creation (Minneapolis, MN: Fortress Press, 1993), 206–14.
3. I will not address here arguments concerning the degree to which animals experience pain. This issue is considered by Robert Wennberg in “Animal Suffering and the Problem of Evil,” Christian Scholar’s Review 21 (1991): 120–40. It is obvious to me that, for many animals at least, pain and suffering are a very real conscious experience.
4. C. S. Lewis, The Problem of Pain (New York: Macmillan Publishing, 1962), 129.
5. As stated by John Hick, in Evil and the God of Love, rev. ed. (New York: HarperCollins Publishers, 1977): “For every position that maintains the perfect goodness of God is bound either to let go the absolute divine power and freedom, or else to hold that evil exists ultimately within God’s good purpose” (pp. 149–50).

The script was written by biology student Joy Walters, with help from BioLogos president Darrel Falk.

As we discussed yesterday, the most dramatic innovation yet observed in the E. coli Long Term Evolution Experiment (LTEE) was the ability, acquired by one of the twelve cultures, to use citrate as a carbon source under aerobic conditions. When we last discussed the LTEE in 2011, we noted what was known then about the mutations that eventually combined to produce the Cit+ trait:

Tracking down the nature of this dramatic change led to some interesting findings. The ability to use citrate as a food source did not arise in a single step, but rather as a series of steps, some of which are separated by thousands of generations:

1. The first step is a mutation that arose at around generation 20,000. This mutation on its own does not allow the bacteria to use citrate, but without this mutation in place, later generations cannot evolve the ability to use citrate. Lenski and colleagues were careful to determine that this mutation is not simply a mutation that increases the background mutation rate. In other words, a portion of what later becomes “specified information for using citrate” arises thousands of generations before citrate is ever used.
2. The earliest mutants that can use citrate as a food source do so very, very poorly – once they use up the available glucose, they take a long time to switch over to using citrate. These “early adopters” are a tiny fraction of the overall population. The “specified information for using citrate” at this stage is pretty poor.
3. Once the (poor) ability to use citrate shows up, other mutations arise that greatly improve this new ability. Soon, bacteria that use citrate dominate the population. The “specified information for using citrate” has now been honed by further mutation and natural selection.
4. Despite the “takeover”, a fraction of the population unable to use citrate persists as a minority. These cells eke out a living by being “glucose specialists” – they are better at using up glucose rapidly and then going into stasis before the slightly slower citrate-eaters catch up. So, new “specified information to get the glucose quickly before those pesky citrate-eaters do” allows these bacteria to survive. As such, the two lineages in this population have partitioned the available resources and now occupy two different ecological niches in the same environment. As such, they are well on their way to becoming different bacterial species.

As such, we noted three distinct steps observed by the Lenski group: steps they call potentiation, actualization, and refinement. Potentiation mutations do not themselves result in the ability to use citrate under aerobic conditions, but they are necessary for it to appear later. Actualization is the mutation that first brings about the Cit+ trait, though, as we noted, this step produced only a very weak Cit+ effect. This nascent ability, however, then undergoes refinement through additional mutations and selection to give the final, robust Cit+ trait observed in the culture.

While some things were known about these steps when the Lenski group last published on this topic (in 2008), the precise details remained unclear. What was needed was a complete characterization of the Cit+ bacteria through whole-genome sequencing to help indentify the changes. These long-awaited results are now available in a new paper published last month by the Lenski group, and they shed light on all three stages of the process.

Lights, camera, actualization

The key step - and the one of greatest interest - is of course actualization: the mutation that converted a Cit- cell to a Cit+ one. This is also one of the easiest steps to study, since the mutation provides the cell with a new feature that can be detected experimentally. Though E. coli cannot use citrate as a carbon source in the presence of oxygen, they are capable of using citrate in anoxic conditions (i.e. when oxygen is absent). To do so, they employ a protein that imports citrate in to the cell while at the same time exporting a compound called succinate. Since this protein is already present in the E. coli genome, it was long suspected that a genetic regulatory change that turned on its production in the presence of oxygen could be the key innovation that produced the first Cit+ bacterium in the culture. As we discussed yesterday, Behe notes that this change could result from a loss-of-FCT or a gain-of-FCT mutation:

“If the phenotype of the Lenski Cit+ strain is caused by the loss of the activity of a normal genetic regulatory element, such as a repressor binding site or other FCT, it will, of course, be a loss-of-FCT mutation, despite its highly adaptive effects in the presence of citrate. If the phenotype is due to one or more mutations that result in, for example, the addition of a novel genetic regulatory element, gene duplication with sequence divergence, or the gain of a new binding site, then it will be a noteworthy gain-of-FCT mutation.”

Interestingly, the actualization mutation was indeed a change of regulation of the anoxic citrate / succinate transporter, and it arose through a gain-of-FCT mutation. The mutation turned out to be a side-by-side duplication of the citrate / succinate transporter gene, as well as portions of two genes on either side of it. This imprecise duplication placed a partial fusion of these flanking genes next door to one of the copies of the citrate / succinate transporter gene. This brought the copy under the control of promoter sequences derived from of one of its neighbors, a gene that is active when oxygen is present. The resulting product was a copy of the citrate / succinate transporter gene that was now very weakly expressed in aerobic conditions. Since this is an example of a mutation that duplicates a gene and simultaneously creates a new regulatory element for it (causing significant sequence divergence), this is a clear-cut example of a gain-of-FCT mutation.

Responding to the data

While Behe has not yet, to my knowledge commented on this particular development within the LTEE, one of his colleagues in the Intelligent Design Movement (IDM), microbiologist Ann Gauger, has offered her thoughts. Two themes emerge in her commentary: that the Cit+ trait is “not new”, and that the number of mutations it required were within the bounds set out by Behe and another member of the IDM, structural biologist Douglas Axe:

When is an innovation not an innovation? If by innovation you mean the evolution of something new, a feature not present before, then it would be stretching it to call the trait described by Blount et al. in "Genomic analysis of a key innovation in an experimental Escherichia coli population" an innovation [...]

The total number of mutations postulated for this adaptation is two or three, within the limits proposed for complex adaptations by Axe (2010) and Behe in Edge of Evolution. Because the enabling pre-adaptive mutations could not be identified, though, we don't know whether this was one mutation, a simple step-wise series of adaptive mutations, or a complex adaptation requiring one or two pre-adaptations before the big event.

But does this adaptation constitute a genuine innovation? That depends on the definition of innovation you use. It certainly is an example of reusing existing information in a new context, thus producing a new niche for E. coli in lab cultures. But if the definition of innovation is something genuinely new, such as a new transport molecule or a new enzyme, then no, this adaptation falls short as an innovation. And no one should be surprised.

While Gauger does not speak to the tension between her description of the Cit+ mutation as “not genuinely new” and Behe’s criteria that this should be classified as a gain-of-FCT mutation, it is clear that she views this event as within Behe’s “edge” – i.e. within the bounds of “what Darwinism can do.” Additionally, she sees it as falling within the scope of what is evolutionarily possible as proposed by Axe’s work. In the next installment of this series, we’ll revisit how Behe defines his (claimed) limit of what evolutionary processes can accomplish, with this new evidence in hand. In doing so, a careful examination of the potentiation and refinement phases of the Cit+ transition will be informative.

For further reading:

Blount, Z.D., Barrick, J.E., Davidson, C.J. and Lenski, R.E. (2012). Genomic analysis of a key innovation in an experimental Escherichia coli population. Nature 489; 513- 518.

Michael J. Behe, The Edge of Evolution: The Search for the Limits of Darwinism (New York: Free Press, 2007).

Michael J. Behe (2010). Experimental evolution, loss-of-function mutations, and “The first rule of adaptive evolution”. The Quarterly Review of Biology 85(4); 419-445.

It’s true that physics sounds scary to many people, and it can indeed be a difficult topic to learn. Yet I’ve always loved physics (my degrees are in physics rather than astronomy), because of the way that mathematical equations can describe and predict so much of what we see in the world around us. One reason I got into astrophysics is because the universe contains so many bizarre situations that we can’t reproduce on earth, like ultracold, or extremely high density, or extremely high magnetic fields. It’s a fun challenge to figure out which physical process will be the most important when the situation is so dissimilar to everyday experience. But if the word “physics” makes you shrink in distaste or fear, don’t worry. For the rest of this article, we’ll focus on a more friendly topic: astronomy.

In the last decade or two, our knowledge of the universe has grown dramatically as many new telescopes and spacecraft have come online. In this essay, I’ve selected some of my favorite recent astronomy photographs to share with you. As a professional astronomer and a Christian, I feel God has called me to share these wonders with the Church. Many times, these new discoveries are presented without any mention of God, and sometimes in a context of overt atheism. I want to share these things with you in a Christian context, with God as their creator.

The Milky Way

Have you ever seen the Milky Way? If you live in a rural area, you may have seen it many times. If not, it may have been a dramatic surprise when you first saw it while camping or traveling. On a clear night out in the country, the sky is strewn with brilliant stars—many more stars than you can see under city lights.The faintest stars form a creamy, smoky band from horizon to horizon. Our galaxy contains billions of stars, and thousands of those stars are visible to the naked eye. The stars appear in a band across the sky because we are viewing our galaxy edge-on, like looking at the edge of a dinner plate.

When David looked up at the night sky over Israel thousands of years ago, he may have seen the Milky Way, or a comet, or simply the brilliance of the full moon. Whatever the sky looked like that night, it inspired him to sing:

The heavens declare the glory of God; the skies proclaim the work of his hands. Day after day they pour forth speech; night after night they reveal knowledge. They have no speech, they use no words; no sound is heard from them. Yet their voice goes out into all the earth, their words to the ends of the world. (Ps. 19:1-4a)

The heavens are displaying the glory of God for all people to hear, proclaiming their message to people of every language, tribe, and nation. Just about anyone who looks up at the night sky feels a sense of wonder. Yet as Christians, we feel more than a vague sense of awe; we know the Creator of the heavens personally, as our own loving Father.

The heavens declare more than God’s glory. The universe is God’s revelation of himself to us, and teaches us about his character. As the Belgic Confession says about “The Means by Which We Know God,”

We know him by two means: First, by the creation, preservation, and government of the universe, since that universe is before our eyes like a beautiful book in which all creatures, great and small, are as letters to make us ponder the invisible things of God: his eternal power and his divinity, as the apostle Paul says in Romans 1:20. Second, he makes himself known to us more openly by his holy and divine Word, as much as we need in this life, for his glory and for the salvation of his own. (Article 2)

The natural world teaches us about God’s glory, power, divinity, faithfulness, extravagance, immensity, love, and other attributes. God’s special revelation in scripture is our primary place to learn of God’s character (Ps. 19 goes on to talk about special revelation in vs. 7), but the natural world can bring the message to our senses in a powerful way beyond mere words on a page. The Holy Spirit can use the natural world to get the message past our hardened or weary hearts. Nature illustrates these attributes in ways that enlarge our imaginations to appreciate afresh the glory of God.

The Sun

The Solar Dynamics Observatory was launched into space in 2010, the latest of several spacecraft to photograph the sun in detail. In Figure 2, the upper photo shows the face of the sun with a sprinkling of sunspots. The sun is powered by nuclear fusion reactions deep in its core which heat the hydrogen and helium gas till it glows. A sunspot is a place on the sun’s surface where the gasses are a bit cooler than the surrounding area, so that it glows less brightly and appears dark.

The lower photo in Figure 2 was taken the same day, but in X-ray light. X-rays are invisible to our eyes, but you have experienced them at the dentist’s office. There, the X-rays are produced by a machine, travel through the mouth, and are detected by film to reveal an image of your teeth. In this image, X-rays are produced by the sun, travel to the Solar Dynamics Observatory, and are detected by a camera to show an image of the sun. In X-rays, the sunspots are the brightest part of the image, not the faintest. If you look at the sunspot on the left edge, you can see bands of particles rising out of the sunspot in a looping path above the sun’s surface and falling back down on it. As the particles follow lines of magnetic field, they emit X-rays. The loops you see are not small—they are about the size of planet Earth! Because of modern spacecraft, telescopes, and cameras, we can see so much more in the heavens than what is visible to the naked eye. Thus, we are seeing more of what the heavens have to declare about God. In Psalm 19, David goes on to describe the sun:

In the heavens God has pitched a tent for the sun. It is like a bridegroom coming out of his chamber, like a champion rejoicing to run his course. It rises at one end of the heavens and makes its circuit to the other; nothing is deprived of its warmth. (vs. 4b-6)

If David had lived today, maybe he would have written about other properties of the sun, like the power of God as seen in nuclear reactions and looping magnetic fields. As it is, he makes two important points. One is the universal warmth of the sun, by which God provides for all life on earth. The other is the faithful path of the sun, day after day, unchanging year after year. In the book of Jeremiah, God promises his people that he will not break his covenant with them, any more than he would break his covenant with day and night and the fixed laws of heaven and earth (33:19-26). The sun is a persistent reminder, woven into our lives, of God’s faithfulness to his promises.

As Christians and geologists, we frequently encounter people with stories of storm tossed and shipwrecked faith that started when they began to wrestle with apparent conflicts between science and the Bible. The stories have a common thread. The Bible, they were told, clearly teaches the earth was created a few thousand years ago with life forms fashioned more or less as we find them today. Because the earth is very young, the incredibly complex sequence of rock, sediment, and fossils found on our planet must have been deposited in a very short period of time. Noah’s Flood, as the only plausible causal agent, was obviously a global and violent event. Theories of an ancient earth and adaptation of life forms, they were further informed, have been constructed on flimsy evidence created by atheistic scientists searching for ways to expunge God from modern culture. But as these sojourners began to explore and understand the actual evidence for an ancient earth, they found themselves increasingly convinced of its legitimacy, and thereby increasingly questioning the veracity of their faith – many to the point of relegating Christ to just another wishful myth.

It is our conviction that these stories of strained or lost faith derive not from an inherent unwillingness to trust the Bible, but rather from misguided teaching on the message of Scripture. Those insisting the earth is young are not simply putting their faith in God’s Word, they are putting their faith in their own particular interpretation of that Word. As such, an entirely unnecessary stumbling block to faith is created, where faith in Christ first requires rejection of sound science.

As we have prayed and studied this subject, we have felt God’s call to speak out against this misplaced stumbling block. We are sensitive, however, to the fact that when scientists speak on issues of faith, there is a natural suspicion that science will be regarded as the ultimate arbiter of truth, and Scripture will have to yield whenever conflict arises. It is thus important for us to state here that both of us ascribe to the authority and inspiration of Scripture, the reality and necessity of Christ’s death and resurrection, the existence of genuine miraculous events, and the truthfulness of the Biblical historical narratives. In our understanding, science will never trump Scripture, but by virtue of science being a study of God’s natural creation, it may occasionally assist in our understanding of God’s written Word. Where this has occurred historically and has been accepted by the Church, the invariable result has been the abandonment of an interpretation of some secondary importance, without any change in our understanding of the intended central message.

This phenomenon is illustrated well by the 17th century clash between Galileo’s claims that the earth revolves around the sun, and the multiple passages in Scripture that appear to clearly present a static earth as the physical center of God’s natural creation. The Bible tells us repeatedly that the earth is fixed upon its foundations (Ps 93:1, 104:5) and the sun rises and sets (Eccl 1:5, Ps 19:6). Within the context of the historical narratives (which we are not accustomed to interpreting in any figurative manner) we read statements about “the sun rising over the land” (Gen 19:23), and a miraculous event during a famous battle where “the sun stopped in the middle of the sky and delayed going down a full day” (Josh 10:13). Likewise in the Levitical law, we find commands to complete the Passover sacrifice “when the sun goes down” (Deut 16:6).

God’s people had interpreted these verses for thousands of years to be authoritative statements about both spiritual and physical realms, and 17th century believers understandably struggled with allowing science to alter traditional interpretations. If God says the sun rises and the sun sets, how could it be otherwise?

Fast forward a few centuries, and we are now somehow quite content to have allowed science to alter our thinking on these verses, without abandoning notions of inerrancy or inspiration. The reason is simply because it was eventually recognized that the primary message of these verses was never on the nature of nature, but on the nature of man and his experience with his environment and his God. Solomon and Joshua accurately recorded their experience from an earthly perspective (sun rising and setting), and David praised God for holding the earth fixedly in His hand (Ps 93:1, 104:5), without requiring a meaning of fixity in space. The central message of these verses was apparent to readers before and after Galileo. Only a secondary interpretation, likely never intended by the writers, was cast off after scientific advances.

So what is the issue regarding Noah’s Flood? The modern debate centers around two questions. Was it truly global in extent, and can the Flood account for the earth’s complex geologic record? To address the first, it is worth being reminded of the Apostle Paul’s letter to the church in Rome where he makes a statement that “your faith is being proclaimed throughout the whole world” (Rom 1:8). Entire people groups existed at this time in China, Australia, and North and South America who knew nothing of the church in Rome. Though using wording that literally means the entire world population, Paul is clearly referring to the world known to him and his readers at the time.¹ Paul speaks truthfully from his experience. Allowing for the possibility that Noah’s Flood encompassed all of known humanity without necessarily covering the entire planet is thus consistent with how other passages in Scripture are interpreted by Christians who believe the Bible is authoritative and trustworthy.

Our primary interest in this blog series is the second question, the widely promulgated notion that the Flood can account for the earth’s complex geology, and that all genuine Christians should accept this viewpoint.

Notes

1. Many Biblical scholars define a literal interpretation as one that takes into account the literary genre, figures of speech, context, and author/audience perspective in deriving the intended meaning. By this definition, poetry and allegory are literally interpreted as figurative. In this blog and in our article, our use of literal conforms to its more common definition where a literal interpretation is one that adheres to the precise definition of words without figurative meaning and without requiring additional context to understand.

In his essay for that series, Jeff Schloss addressed the question of whether animal death is a natural evil, but also noted that such theological considerations aside, death does not actually “drive evolution” in the way most people imagine—especially when they think of violence in the natural world. This more complicated sense of death’s role is partially the result of modern evolutionary science recognizing the importance of cooperation and inter-relation among species, rather than just direct competition. But just as important is the knowledge that evolution is significantly shaped not by the deaths of individual creatures, but by extinction, the loss of species over time. In this post, we explore some aspects of how extinction acts as both a destructive and creative force in evolutionary history, including the evolutionary history of mammals.

Sporadic extinction

Extinction is actually a common feature of life on earth when viewed over long (e.g. geological) timescales. By some estimates, over 99% of the species that have ever lived have gone extinct. One factor that promotes extinction is the fact that evolution does not produce species that are optimally adapted to their environment, but only better adapted than their local competitors. Invasive species testify to this fact: local (endemic) species are not always the best-adapted species for their own environment. Examples abound where species from other environments are actually better-suited to out-compete endemic species. Here in my own province, the invasive Himilayan blackberry (Rubis discolor) easily outcompetes many endemic species. If endemic species were optimally adapted to their environment, this would not be possible, as they would outcompete all exotic species. Instead, exotic species, by chance, might be better adapted to an ecosystem they did not evolve in. These exotics may be capable of eliminating endemic species altogether.

Such an extinction event (of a single species, or perhaps a handful of species) alters the environment of other remaining species in an ecosystem. This, in turn, may influence the ability of some of these remaining species to reproduce compared to other species. For example, the extinction of a competitor might allow a species to increase in population size. Conversely, the extinction of a species that provides a benefit (such as a pollinator) may reduce a species in number. As the ecosystem landscape shifts due to loss of species, new biological opportunities, or niches, might arise. These new niches are then available to support new species to fill them.

Extinction, en masse

One way to appreciate how extinction opens up new niches is to examine mass extinction events – geologically brief periods where large numbers of species go extinct at the same time. Over the history of life on our planet there have been several mass extinction events. The largest such event, at the end of the Permian (~250 million years ago) appears to have been caused, at least in part, by intense volcanic activity over several hundred thousand years. This activity likely shifted CO2 levels and eventually led to a “runaway” greenhouse effect that dramatically raised global temperatures and led to anoxic (i.e. oxygen-depleted) oceans, though the exact contributions of these varied factors remains an area of scientific debate. What appears certain is that during this period environmental changes were too rapid for most species to keep evolutionary pace with, and as a result over 90% of the world’s species alive at that time went extinct. Obviously this represents destruction of biodiversity on an unimaginable scale, and the destructive effects of this event are with us to this day.

Speciation, en masse

This destruction, however, is not the whole story. Following on from the Permian mass extinction, we observe a steady increase in new species. These are species previously unknown in the fossil record. In fact, this pattern (a “radiation” of new species following an extinction event) is the rule, not an exception – we see the same effect after every mass extinction in the fossil record. Extinction is a driving force for novelty.

Perhaps the most famous mass extinction event is the Cretaceous – Paleogene (KPg) extinction, and it too follows this standard pattern. This mass extinction took place 65 million years ago when an asteroid ~10 kilometers in diameter struck the Yucatan peninsula. (Note: this event was formerly known as the Cretaceous – Tertiary (K-T) extinction, but that terminology is in decline within the scientific community). This extinction event is famous since it is the one that eliminated the dinosaurs (with the exception of the ancestors of modern birds). As with the Permian extinction, the elimination of so many species shifted the evolutionary landscape for the remaining species, and the result was a burst of speciation that appears rapid when viewed in geological time. Significantly for our own species, following the KPg extinction event is a burst in mammalian speciation, as small mammals that survived the event diverge and fill niches left empty by the dinosaurs. Without this event, the trajectory of mammalian evolution would certainly look very different.

Clearing the deck, and re-filling the niches

One interesting fact to note is that biological features that make a species resistant to usual, sporadic extinction are not necessarily the same features that will be useful during a mass extinction event. While species are continually under selection at the local level, there is no mechanism for (pre) selection to survive a mass extinction. As such, only species that happen to have the right combination of traits will survive, and often spread widely after a mass extinction. These so-called “disaster species” are usually generalists, and will later be displaced by more specialized species as they arise. As such, where sporadic extinction allows for more gradual turnover in species, mass extinction events are major “resets” of evolution that can radically shift what constitutes “well adapted” in a geological eyeblink. For mammals at the KPg boundary, small body size and an omnivorous diet (including the ability to scavenge detritus) were the “winning” combination of traits that allowed them to survive where larger, more specialized animals (think Tyrannosaurus rex) could not. From this rather humble station, mammals would come to dominate the world’s ecosystems over the coming eons – including a lineage that would someday lead to our own species. Far from only a destructive force, extinction is a powerful mechanism to allow evolutionary innovation, and one that was of significant importance to us.

For further reading:

Meredith, R.W. et al (2011). Impacts of the Cretaceous Terrestrial Revolution and KPg Extinction on Mammal Diversification. Science 334; 521-524.

Fastovsky, D.E. (2005). The Extinction of the Dinosaurs in North America. GSA Today (15); 1052-5173.

Benton, M.J. and Twitchett, R.J. (2003). How to kill (almost) all life: the end-Permian extinction event. TRENDS in Ecology and Evolution (18); 358-365.

The Evolutionary Role of Death & Natural Evil

In addition to providing a general theological critique of the endemic—as opposed to post-hoc or intrusive—origins of death in the natural world, John Laing’s imminently fair-minded essay also takes theological aim at the role death and natural evil play in the evolutionary diversification of life. It is one thing to say that death is primordial; it is another to view it not just as an ancient byproduct, but as the central means of creation. The understandable theological uneasiness expressed by John and many others about this issue ultimately rests not just on an understanding of God’s creative activity, but also on a particular representation of evolution. In this regard John makes two important claims:

• a) “…natural selection, with its emphasis on a natural state characterized by competition for limited resources and a general struggle for survival, is the primary means by which speciation takes place…”
• b) “death actually functions as a mechanism for life. Death plays a vital role in natural selection by rooting out weakness and driving evolutionary development.”

For reasons I discussed in the previous section, it is not entirely clear that death constitutes an evil that is incommensurate with divine activity. However, the fact is that the above depiction of evolution—which is not unique to John amongst public commentators and is largely commensurate with Darwin’s own views—does not adequately portray current discussions within evolutionary biology. There are three problems with this portrayal that I’d like to address in turn—three aspects of evolutionary theory that need to be better understood.

First, while there is no uncertainty about common descent or about natural selection as a cause of evolutionary change, there is considerable discussion over the extent to which natural selection is “the primary means” by which speciation takes place. For one thing, there are manifold other agents of evolutionary change: drift, gene flow, systems of mating, mutation itself unfiltered by selection. A tremendous amount of variation may be adaptively neutral, being invisible to natural selection. For another thing, some claim that evolution proceeds most rapidly and speciation occurs most precipitously in the relaxation of selection—when ecological times are good and the culling effects of the environment are minimized. We may see this in the contingency-driven formation or colonization of a new habitat or the exploitation of a new resource that does not displace previous variants. Or, speciation events or species-level innovations may be the results of chromosomal rearrangements or symbiogenesis that are not the cumulative results of selection. Finally, there exist manifold and admittedly controversial proposals that are critical of neo-Darwinism as a whole, claiming that natural selection may be a necessary, but is neither a sufficient nor a primary cause of large-scale evolutionary change.¹

Second, notwithstanding Darwin’s formulation of natural selection in terms of competitive struggle as (accurately) cited by John, the modern understanding of evolution and competition is considerably more differentiated and complicated. For one thing, competition is neither a necessary nor a sufficient condition for natural selection. Natural selection is formally defined as the differential reproduction of genotypes (or information.) Some sets of genes are replicated with greater efficiency than are others. Competition is formally defined as the negative impact of two organisms (or two species) on one another’s fitness. You can have all sorts of competition that does not result in natural selection. And importantly, you can have differential reproduction by natural selection without the negative fitness impacts of competition. Colonists to a new under-exploited habitat, or two species that are partitioned onto separate resources in a way that minimizes competition might well have some variants that leave more offspring than others without displacing them. This is natural selection.

Indeed, imagine an infinite habitat with non-limiting resources and no competition at all: as long as there were adaptively salient mutations, there would be natural selection—some of those new genotypes would reproduce more effectively than others. Competition, to whatever extent it exists in nature, is a consequence of finitude and not a necessary precondition of natural selection. And finally, the role of cooperation in evolution has itself been massively reconsidered in recent years. It would not be entirely unfair to say that on the basis of mathematical models and empirical data, the proposal that cooperation “is now seen as a primary creative force”² and a “fundamental principle of evolution”³ has moved from being a cult-alternative to a widely accepted paradigm. Indeed, cooperation and increasing scales of cooperative interdependence are seen not only as a formative process but also as a recurring product of evolutionary change, which may even be viewed as “progress.”⁴ A biologically significant and theologically salient thematic trend across major evolutionary transitions, is that cooperative interdependence itself – and the wondrous properties of life mentioned in the first installment of this essay – seem to be amplified through selection.⁴ Through evolution, God may be seen to confer life and confer it in greater abundance.

Third, the claim that “death drives evolutionary development” turns out to be problematic. Recent discussions of death and senescence (organismic decay) between various branches of the biosciences are spirited and fascinating. One of the vexing characteristics of living creatures is the internalization of death and senescence: even if an individual is not killed by external forces, it will die from the inside out—virtually no species is immortal.⁶ One account of this—the rate of living theory of senescence—understands it not in terms of selection for reduced mortality but in terms of biophysical or allometric constraints relating rate of metabolism to rate of wearing out. Though it views senescence differently, the prevailing evolutionary theory of senescence, with several variants, does not affirm death or decay—at least the kind of death and decay that is intrinsic to organismic development—as a prerequisite to evolution by natural selection either.⁷

Indeed, internalized death is viewed not as driving but as deriving from, not as a necessary requirement for but as a byproduct of, natural selection. Specifically, mutations or traits with detrimental impacts later in life may not be eliminated by or may even be favored by selection if their contribution to reproduction early in life is sufficient. Now, neither theory completely dismisses the shaping role of death. Under certain but not all conditions, differential mortality may have adaptive import (and it is not even the longer-lived organisms that always have adaptive advantage). Extrinsic sources of death may also shape the internalization of death.⁸ But the view that death drives evolution does not adequately represent emerging scientific understanding of the relationship between natural selection and senescence.

Scientifically death does not “drive” evolution. And theologically, although neither evolutionary change nor ecological interaction “solve” the ultimate puzzle of human death, they may nevertheless mitigate the proximal existence of creaturely death by amplifying the complexity and vibrant abundance of living forms.

Darwin famously closed The Origin by observing “There is a grandeur in this view of life, with its several powers, having been originally breathed by the Creator into a few forms or into one…from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved.”⁹ Unlike John, I do not see anything in evolutionary theory to reduce, and I see much to augment the sense of grandeur and (for that matter) the appreciation of sheer goodness—both earthly and divine—evoked by the wonders of the living world.

Yet grandeur and goodness are not perfection. My Dad is still dying. I still wince at the suffering of clearly sentient animals. And, truth be told, I tremble at the biblical images of universal herbivory: even metaphors are metaphors of something, and in the case of biblical revelation, that something can be taken to be real and important. So like John, I confess to profound gratitude tempered with a lingering unease at the state of nature. Though I believe in a Fall, this unease is not rationally relieved by attributing to an Adam the present state of all nature. Nor is it resolved by the various alternative considerations I’ve described and which, taken together, seem to have considerable merit but not sufficiency. Notwithstanding, I thankfully affirm that “I have known the goodness of the Lord in the land of the living.” And I look to the day when we may say together, “My ears had heard of You, but now my eyes have seen You.” (Job 42:5)

Notes

1. E.g., Salthe, S. 2008. “An Anti-Neo-Darwinian View of Evolution.” Artificial Life. 14:231-233; David Depew and Bruce Weber (eds). Darwinism Evolving: Systems Dynamics and the Genealogy of Natural Selection. 2004. MIT Press
2. Michod, Richard and Denis Roze. 2001. “Cooperation and Conflict in the Evolution of Multicellularity.” Heredity. 86:1-7. Page 2
3. Nowak, Martin. Evolution, Games, and God: The Principle of Cooperation. Martin Nowak & Sarah Coakley, eds. Forthcoming from Harvard University Press.
4. Sigmund, Karl and Eörs Szathmáry. 1998. “Merging Lines and Emerging Levels.” Nature. 392: 439-441.
5. John Maynard Smith and Eörs Szathmáry. 1998. The Major Transitions in Evolution. Oxford University Press. Brett Calcott & Kim Sterelny (eds). 2011. The Major Transitions in Evolution Revisited. MIT Press.
6. “Virtually” is an important qualifier: while senescence has been documented in nearly all organisms examined, there are some cell lines and species in which this may not be the case.
7. Williams, George. 1957. “Pleiotropy, Natural Selection, and the Evolution of Senescence.” Evolution. 11:398-411.
8. This relationship is complex and not invariant. E.g., Williams, Paul and Day, Troy. 2003. “Antagonistic Pleiotropy, Mortality Source Interactions, and the Evolutionary Theory of Senescence.” Evolution. 57(7): 1478-1488.
9. Darwin, Charles. 1876. The Origin of Species By Means of Natural Selection, or the Preservation of Favored Races in the Struggle for Life. 6th Edition. John Murray. p. 429.

Recently, an elegant and powerful experiment was done to further investigate a question of interest to many evangelicals: how is it that we are so different from our closest biological relative (the chimpanzee) when our DNA is so very similar? Even when using estimates that maximize the differences, our genomes are 95% identical. The conclusion, that I have discussed here in the past is that a dispersed set of numerous small changes can have large effects on the form and function of an organism. Of course, small changes are what evolution specializes in: tinkering here and there, one mutation at a time, as we have directly observed in laboratory experiments. Before we discuss how this pivotal new study was done, however, a brief review of how genes work is in order.

Review: gene structure and function

If you’ve been following the ongoing Understanding Evolution series here at BioLogos, you will recall that we discussed gene structure and function not long ago, in the context of discussing non-functional DNA sequences (so-called “junk DNA”):

Genes have a typical structure (obviously simplified here somewhat). First off, there is the actual DNA sequence that specifies the protein product sequence (the so-called “coding sequence”, shown in blue). This sequence is usually broken up into segments in mammalian genes, and these sequences are spliced together when the DNA sequence of the gene is transcribed into a “working copy” called mRNA – a short duplicate of the code that can be used by the cell’s machinery to actually build the specified protein.

In addition to the actual coding sequences, other sequences are needed to tell the cell when and where certain genes should be transcribed into mRNA. Every cell in an organism has the same genes in their chromosomes, but not all are transcribed. Using different genes in different combinations is what makes cells take on distinct roles – for example, cells in your small intestine need different genes (for absorption of nutrients) than do cells of the immune system (for fighting off pathogens). Regulatory sequences make sure any given cell type has the right genes transcribed and made into protein products. Some of these sequences are part of the mRNA transcript (shown in red), and others are not transcribed but only part of the chromosomal DNA sequence (such as the “promoter” region that directs the enzymes responsible for making the mRNA transcript (shown in blue).

With this background in mind, we can now extend our understanding slightly further. DNA in cells is “packaged up” when not in use by winding it around a class of proteins called histones. This packaging keeps the DNA in a compact form, and it is useful in helping cells prevent genes they don’t need from being transcribed. For any given chromosome - which is one long strand of DNA – some regions will be packed away (and the genes there not transcribed), while other regions are unpacked (less tightly associated with histones) with the genes there actively undergoing transcription. The open regions allow for transcription because enzymes and other proteins needed for the process can gain access to the DNA there.

Comparing gene transcription across species at the genomic level

Because of the overwhelming similarity between the human and chimpanzee genomes (and the even greater similarity when examining only their protein-coding regions) it has long been hypothesized that changes in “where and when” genes are transcribed will be a major player in what makes our two species different (in contrast to the idea that we are different because of the relatively tiny changes in the coding regions of our genes). From an evolutionary point of view, there are a few ways to explore how differences in gene transcription arise once species go their separate ways, such as when our ancestors parted ways with our last common ancestor with chimps around 4-6 million years ago. The main idea is to compare the same cell type in both species: human skin cells versus chimp skin cells, for example. Determining what specific genes are transcribed (or not) in human cells and comparing the results to chimpanzee cells gives us an idea of how gene transcription differences arose in the two lineages since they last shared a common ancestor. The challenge, up until now, is that there was no easy way to indentify the changes in regulatory DNA that led to those differences in transcription. The problem arises because of the overwhelming similarities between our genomes: changes in transcription due to changes in DNA sequence are hard to find simply by looking for sequence differences, since in most cases the differences will be very small. There are also many small differences between our genomes that have no effect on gene transcription, so we cannot simply look for any difference at all. What we need is a way to identify which small changes led to differences in gene transcription.

Old hypotheses, new technology

Back in 2008, a method for addressing this issue was devised. As we have seen, DNA undergoing transcription is “unpacked” and accessible to enzymes. Researchers have long known about a certain enzyme, called DNAse I, that can cut exposed DNA but leave histone-packaged DNA alone. This means that DNA from any given cell type can be cut using this enzyme specifically at “DNAse I hypersensitive sites” (DHS’s) where regulatory DNA is unpackaged and a nearby gene is being transcribed. While this technique is decades old, what is new is a way to then go on to sequence the DNA next to each of these sites. This requires what is known as “next-generation” or “deep” DNA sequencing methods that can use a linker sequence to attach to the DNAse I cut sites and then amplify and sequence individual DNA fragments attached to the linker. Since we have the entire genome sequence of humans and chimps it is then trivial to take the sequencing results and map them to either genome. The results are a detailed map of what chromosome regions are unpacked and regulating transcription in each cell type. These maps can then be compared with related species across entire genomes.

It was only a matter of time before these powerful methods were applied to the human-chimp question, and the first results became available last month. The research group was of course interested in differences between the two species, and the results are fascinating. The researchers looked at several different cell types, and found similar results in all cases. The results for any given gene fall into one of several categories when compared to the human-chimp (H-C) last common ancestor:

• No differences in regulatory DNA relative to the H-C last common ancestor (1259 genes)
• Gain of regulatory DNA in humans relative to the H-C last common ancestor (836 genes)
• Loss of regulatory DNA in humans relative to the H-C last common ancestor (286 genes)
• Gain of regulatory DNA in chimpanzees relative to the H-C last common ancestor (676 genes)
• Loss of regulatory DNA in chimpanzees relative to the last common ancestor (211 genes)

While it was not surprising to find a significant percentage of unchanged genes, it was interesting to note the large percentage of differences in regulatory DNA, despite the overwhelming genomic similarity between the two species. Small changes had a large impact on gene regulation. The researchers went on to examine the new regulatory regions they had identified, and found that they showed evidence of being under natural selection. These mutations had not only brought change, but provided an advantage to their hosts.

These results underscore a few important points:

• Species become different because differences accumulate in both lineages once a common ancestral population splits into two. The differences we see in modern species are due to changes both species have accumulated over time.
• Tweaking the regulation of numerous genes appears to be a widespread mechanism for generating evolutionary novelty. Both gaining and losing regulatory sequences is common.
• These gains or losses in regulatory DNA require only very small changes at the DNA sequence level, but they can have profound impacts on how genes are transcribed.
• These changes appear to be widespread in genomes, and able to accrue in short evolutionary timescales.
• Small changes are exactly the sort of thing that evolution is known to be able to accomplish easily, one mutation at a time.
• These small changes bear the marks of natural selection, indicating that they were selected for as they arose.
• Anyone who wishes to call these differences “insignificant” will have to contend with the observation that the biological differences we observe between humans and chimpanzees are significant.
• Small, incremental changes at the genomic level fit nicely with the fossil evidence for human evolution, which, though fragmentary, indicates gradual changes in skeletal morphology over the same timescale.

Of course, this study is just the beginning, and future studies are sure to examine and compare additional cell types found in humans and our evolutionary cousins. These results have already added to the troubles of antievolutionary groups that wish to portray the differences between us as too great for evolutionary mechanisms to bridge. I suspect these troubles will only worsen in the coming years as these new techniques come into their own.

For further reading:

Shibata Y, Sheffield NC, Fedrigo O, Babbitt CC, Wortham M, et al. (2012). Extensive Evolutionary Changes in Regulatory Element Activity during Human Origins Are Associated with Altered Gene Expression and Positive Selection. PLoS Genetics 8(6): e1002789. doi:10.1371/journal.pgen.1002789

http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.1002789

(Click image for full resolution)

In a Nutshell

In Detail

Introduction

Astronomers and geologists have determined that the universe and Earth are billions of years old. This conclusion is not based on just one measurement or one calculation, but on many types of evidence. Here we will describe just two types of evidence for an old Earth and two types of evidence for an old universe; more types can be found under Further Reading. These methods are largely independent of each other, based on separate observations and arguments, yet all point to a history much longer than 10,000 years. As Christians, we believe that God created the world and that the world declares his glory, so we can’t ignore what nature is telling us about its history.

Age of the Earth from seasonal rings and layers

If you’ve ever seen a horizontal slice of a tree trunk, you’ve seen how a tree forms a new growth ring each year. In years of drought, the tree grows less quickly so the ring is narrower; in good growing seasons the ring is thicker. A tree’s age can be found by simply counting its rings. By comparing the pattern of thick and thin rings to weather records, scientists can verify that the method is accurate. This method can even be used on dead trees that fell in a forest long ago. For example, the last 200 rings in the dead tree might match up with 200 rings early in the life of the living tree, so the two trees together can count back many years. In this way, multiple trees can be used to build a master chronology for a forested region. European oak trees have been used to build a 12,000-year chronology.¹

The annual ice layers in glaciers provide a similar method that goes back much further in history. Each year, snowfall varies throughout the seasons and an annual layer is formed. Like the tree rings, this method can be verified by comparison to historical records for weather, as well as to records of volcanic eruptions around the globe that left thin dust layers on the glaciers. Scientists have drilled ice cores deep into glaciers and found ice that is 123,000 years old in Greenland² and 740,000 years old in Antarctica.³ These annual layers go back much farther than the 10,000 years advocated by the young earth creationists. The Earth must be at least 740,000 years old.

How can an old Earth be reconciled with Genesis? See Scripture Interpretation

Age of the Earth and solar system from radiometric dating

In your high school science classroom, you may have seen a large poster of the periodic table hanging on the wall. The periodic table shows the types of atoms that make up the world around us. An element in the periodic table can come in different flavors called isotopes. Some isotopes are unstable, and over time these isotopes “decay” into isotopes of other elements. For example, Potassium-40 is unstable and decays into Argon-40. As time passes, a rock will have more and more Argon-40 and less and less Potassium-40. Radiometric dating is possible because this decay occurs at a known rate, called the “half-life” of the radioactive element. The half-life is the time that it takes for half the radioactive sample to change from one element into the other.

Some isotopes have short half-lives of minutes or years, but Potassium-40 has a half-life of 1.3 billion years. Radiometric dating requires that one understand the initial ratio of the two elements in a given sample by some means. In this case, Argon-40 is a gas that easily bubbles out and escapes when it is produced in molten rock. Once the rock hardens, however, all the Argon-40 is trapped in the sample, giving us an accurate record of how much Potassium-40 has decayed since that time. So, if we find a rock with equal parts Potassium-40 and Argon-40, we know that half the Potassium-40 has decayed into Argon-40, and that the rock hardened 1.3 billion years ago.⁴

It’s hard to find rocks on the surface of the Earth that have not been altered over time. Most old rocks have been eroded by wind and water or submerged by continental plates. The oldest reliably dated rock formation is in Greenland, where several different isotopes were used to find an age of 3.6 billion years.⁵ Scientists also recently dated zircon grains (which resist erosion) in Western Australia to 4.4 billion years old.⁶ To find older rocks that haven’t been eroded, we need to look beyond Earth. Meteorites are rocks from the solar system that have fallen to Earth recently and haven’t suffered much erosion. Their pristine interiors give an age that dates back to their formation at the beginning of the solar system. Nearly all meteorites have the same radiometric age, 4.56 billion years old.⁷ Thus, the solar system, including the Earth, is about 4,560,000,000 years old.

PLEASE READ THE REST OF THE ANSWER HERE.

Notes

1. Davis A. Young, ”How Old Is It? How Do We Know? A Review of Dating Methods – Part One: Relative Dating, Absolute Dating, and Non-radiometric Dating” Perspectives on Science and Christian Faith, Vol 58 No 4 (2006), p. 264. (PDF)
2. Roger C. Weins, "Radiometric Dating: A Christian Perspective", The American Scientific Affiliation (2002). See also North Greenland Ice Core Project Members, “High-resolution Record of Northern Hemisphere Climate Extending into the Last Interglacial Period,” Nature 431 (2004): 147–151, which reports ages back to 123,000 years. (web article)
3. EPICA Community Members, “Eight Glacial Cycles from an Antarctic Ice Core,” Nature 429 (2004): 623–628.
4. Young earth creationists reject radiometric dating methods, including claims that decay rates are not constant. For a critical review, see Randall Isaac “Assessing the RATE Project”, Perspectives on Science and Christian Faith, vol 59, no 2, June 2007, p.143-146. (PDF)
5. See Wiens and references therein. (web article)
6. Wilde et al. “Evidence from detrital zircons for the existence of continental crust and oceans on the earth 4.4 Gyr ago,” Nature (2001) 409, 175-178.
7. See Davis A Young, ”How Old Is It? How Do We Know? A Review of Dating Methods—Part Two: Radiometric Dating: Mineral, Isochron and Concordia Methods” Perspectives on Science and Christian Faith, Vol 59, No 1 (2007) and references therein (PDF)
]]> Sat, 14 Jul 12 05:02:55 -0700 http://biologos.org/blog/what-is-the-higgs-boson?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication http://biologos.org/blog/what-is-the-higgs-boson?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication At a press conference on July 4, 2012, and with 99.99994% confidence (5 sigma), CERN announced the discovery of a particle consistent with that of a Higgs boson (a.k.a. “the God particle”). This is very exciting for elementary particle physicists. But what is the Higgs particle, and what is its meaning? At a press conference on July 4, 2012, and with 99.99994% confidence (5 sigma), CERN announced the discovery of a particle consistent with that of a Higgs boson (a.k.a. “the God particle”). This is very exciting for elementary particle physicists. It is also getting the attention of press and general public. But what is the Higgs particle, and what is its meaning?

It has been widely reported that the moniker “God particle” was not its originator’s first choice. Still, Leon Lederman, director emeritus of Fermilab and Nobel laureate for neutrino research, did accept the nickname “God particle” because the particle is “so central to the state of physics today, so crucial to our final understanding of the structure of matter, yet so elusive.” “God particle” was quickly accepted by the press and general public because it seemed an appropriate title for a particle theorized to give mass to all elementary matter particles and the force carrying W and Z bosons. Serving this mass-giving function since near the beginning of the universe, a Higgs field (more fundamental than the actual Higgs boson ) must necessarily exist everywhere in the universe and be unchanging. With an omnipresent and immutable field, analogies between the Higgs boson and God naturally developed within the press and the public—“God particle” became deeply rooted. Relatedly, the Higgs boson become an excellent source for theological analogies. (See for example this article.)

Nevertheless, as physicists seek to emphasize, neither the Higgs boson particle nor its field have religious properties. Thus, elementary particle physicists are not fond of the “God particle” appellation. In the opinion of Oliver Buchmueller, of CERN’s CMS group, calling the Higgs boson the “God particle is completely inappropriate. It’s not doing justice to the Higgs and what we think its role in the universe is. It has nothing to do with God“. As Pippa Wells, another CERN scientist expressed, “Calling [it] the God particle … confuses people about what we are trying to do at CERN”. (Source: Reuters)

One alternate name for the Higgs particle that is used within the physics community is the “BEH” particle. “BEH” stands for Brout–Englert–Higgs, three of the six authors of 1964 papers that first proposed a mechanism for giving mass to elementary particles. In addition to Peter Higgs, the five other authors are Robert Brout and Francois Englert, and Tom Kibble, C.R. Hagen, and Gerald Guralnik. The process for giving mass to particles is thus sometimes referred to not just as the Higgs mechanism, but as the Brout–Englert–Higgs–Hagen–Guralnik–Kibble (BEHHGK) mechanism. (Saying all six names a couple of times makes it obvious why we most often only call it the Higgs.)



But issues of naming aside, what is the Higgs and why is it so elusive? According to the Standard Model, the particles that compose matter (the quarks and leptons) are in a category called spin-1/2 particles. The force carrying particles (the photon, the W's, the Z, and the gluons) are spin-1 particles. What the physicists above proposed was the existence of a type of spinless, or spin-0 particle. Not only does the Higgs boson form its own class of particles, it also gives mass to itself and to all the other particles that have mass: to all of the leptons and quarks, and to the W's and Z bosons, but not photons or gluons. This set of relationships is shown in the image below, indicated by the lines connecting the Higgs to these other particles. There are no lines directly connecting the Higgs boson to photons and gluons because the Higgs boson does not interact with these force carrying particles and, thus, photons and gluons remain massless.



But the story of the Higgs particle actually begins with the associated Higgs field, an invisible field (something like a generalization of an electric field) that has a non-zero, constant value everywhere throughout the universe. This Higgs field continuously interacts with all matter particles and the W and Z force carrying particles. Matter and massive force particles are slowed down as they move through the Higgs field, just as are balls rolling through thick mud. The Higgs field is sometimes described as a “cosmic molasses”. Different particles interact with the Higgs field to varying degrees—those interacting more, are slowed down more, those interacting less are slowed down less. Slowing down more equates to acquiring more mass. If not for the Higgs field, all particles would be massless, zipping through the universe at the speed of light. The universe would be without structure—no galaxies, no plants, no life. Without the Higgs field, not even atoms could have formed.

It should be noted, however, that the majority of the mass of protons and neutrons (and thus of atomic mass) does not come from interaction with the Higgs field. Each proton and neutron is composed of three quarks, which do receive their mass from their interaction with the Higgs field. However, the masses of protons and neutrons are much greater than the sum of their constituent quarks and are a result of the additional mass contribution from the binding energies of the “trapped” quarks.

It was theoretically possible for elementary particles to have mass without needing to acquire it through interaction with a Higgs-like field. However, as the standard model of elementary particles developed in the 1950’s and 1960’s, elementary particle theorists realized that if particles had their own innate mass, rather than acquiring it, many beautiful symmetries of particle interaction equations would be broken. To keep the beauty and symmetry in the theory was the essential reason the BEHHGK mechanism was developed, which immediately led to the prediction of Higgs bosons.

When there is enough external energy in a given volume, the Higgs field also produces Higgs bosons. But the Higgs bosons are very unstable and quickly decay. This is the process that enabled the discovery of the Higgs boson at CERN. At CERN, protons are accelerated to high energies via electric fields and directed in circular paths via magnetic fields. The protons then collide and release large amounts of energy. When sufficient energy is released in a collision, the Higgs field can use this energy to produce Higgs bosons. The Higgs bosons quickly decay leaving evidence of their existence through particular combinations of leftover particles that they have decayed into. Among those predicted by the mathematics of the Standard model are the muons and electrons identified by the CERN experimenters. The image at the top shows the identities and paths of particles produced in one of the CERN proton-proton collisions whose results fit with what would be expected from the decay of a Higgs boson.



For a proton-proton collision at the CERN LHC, the above diagrams show both the dominant modes for creation of a Higgs with a mass around 125 GeV, and the two dominant decay channels (modes). The creation mechanism (shown schematically in the left half of each diagram above) involves virtual gluons, the carriers of the strong nuclear force (represented by squiggly purple lines) from the protons. The gluons fuse into a virtual top quark loop (medium blue triangle), which then emits a Higgs boson (squiggly yellow line). The top quark couples more strongly to the Higgs than any of the five other quarks, so the top quark contributes the dominant loop.

The Higgs boson then dominantly decays into either (i) 2 gamma ray photons (the squiggly green lines) via another intermediate virtual top quark loop or a virtual W gauge particle loop (dark blue triangle), or (ii) two Z0 gauge particles (squiggly dark blue lines), which each then decay into a lepton (specifically an electron or a muon)/anti-lepton pair (light blue lines).

The likely discovery of the Higgs boson, and its implied existence of the associated Higgs field, is an amazing success for CERN. Past research and experience at Fermilab and by elementary particle physicists throughout the world also contributed to the discovery. The Higgs boson was the remaining particle in the Standard Model of Particle Physics to be found. With it, the Standard Model is in some sense complete. (Nevertheless, many questions about the Standard Model still remain—many inspired once again by beauty and symmetry. In particular, several numeric values associated with particle masses and interactions could only be experimentally measured, as with the Higgs, and not predicted from the Standard Model.)

With the apparent success of these experiments and seeming confirmation that the physical universe is, indeed, reflected by the complex and beautiful mathematics of the Standard Model, the international physics community is eager to keep delving deeper into the structure of creation. In addition to trying to verify that the 125 GeV particle is, indeed, the Higgs spinless particle and not some more exotic, new particle, CERN physicists are simultaneously seeking to discover an entire new class of particles, resulting from a theorized symmetry called supersymmetry. Discovery of the associated particles, if they exist, will likely take a few more years. For these discoveries we can only wait in anticipation.





Updated July 12, 2012.

]]> Wed, 11 Jul 12 11:58:56 -0700 Gerald Cleaver http://biologos.org/blog/naming-the-god-particle?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication http://biologos.org/blog/naming-the-god-particle?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication The discovery of the Higgs boson would certainly be a breakthrough for particle physics and cosmology, but would such a finding also radically redefine theology’s understanding of God or challenge the existence of such a deity? Is there actually any theological or religious significance in Higgs physics at all? The image above describes an "event" (proton-proton collision) recorded in 2012 with the CMS detector at CERN's Large Hadron Collider. According to CERN, "the event shows characteristics expected from the decay of the SM Higgs boson to a pair of Z bosons, one of which subsequently decays to a pair of electrons (green lines and green towers) and the other Z decays to a pair of muons (red lines). The event could also be due to known standard model background processes. ATLAS Experiment © 2012 CERN

Judging from the flurry of headlines over the past week, one might be tempted to think that proof positive of God’s existence (or lack thereof) had just appeared out of a 27-km-tunnel buried beneath the Swiss-French border. This frenzy of news headlines and blog titles hailed the recent news that CERN’s Large Hadron Collider has discovered a brand new particle of a mass of 125-126 GeV, which is assumed to be the Higgs boson, or the so-called “God particle.” The discovery of the Higgs boson would certainly be a breakthrough for particle physics and cosmology, but would such a finding also radically redefine theology’s understanding of God or challenge the existence of such a deity? Is there actually any theological or religious significance in Higgs physics at all?

The short answer is “no,” which becomes apparent when one considers the widely-reported story of how it got named. In 1993, Nobel Laureate physicist Leon Lederman, along with science writer Dick Teresi, wrote a book detailing the history of particle physics starting with Pre-Socratic Greek philosophy Democritus and culminating with the hunt for the Higgs boson. Until this latest discovery, the Higgs boson was the elusive final missing piece of the puzzle known as the Standard Model—a collection of the fundamental particles that constitute our universe and the complex and mathematically-sophisticated relationships between them. Considering how incredibly difficult finding the Higgs boson was proving to be, Lederman wanted to name the book after that “goddamn particle,” according to some of his collaborators. His editor, however, would not allow it and so the name was shortened to “The God Particle: If the Universe Is the Answer, What is the Question?” And thus ‘the God particle’ was born, carrying with it more than enough social baggage for such a miniscule particle.



Particle physicist Dr. Zosia Krusberg (at right) is visiting assistant professor of physics and astronomy at Vassar College and thinks “the term ‘god particle’ is unfortunate. The Higgs boson is no more (or less) divine or spiritually significant than any other elementary particle within the standard model of particle physics.” It may be fundamental to explaining one of the most basic characteristics of the universe—namely the existence of matter and mass in addition to energy—but “it is no more (or less) important than any other physics principle underlying the Standard Model.”

Last week’s discovery was monumental in that it may have finally provided experimental evidence for the Higgs Mechanism and defined the specific energy of the resulting Higgs boson, but even this “breakthrough” for particle physics leaves many scientific questions unresolved. Finding the Higgs boson completes the Standard Model, but it does not do away with many other questions and shortcomings of the current state of particle physics, such as the constituent particles of dark matter, a quantum theory of gravity, and other “mathematically subtle problems.” Not to mention that there is still significant work to be done to determine the exact nature of this newly-found particle. According to Dr. Krusberg, this particle might behave just as the Standard Model predicts or it could instead be “a Higgs-like particle that will serve as a gateway into explorations of physics beyond the Standard Model." Krusberg continued, “And I guarantee that it is this latter scenario that most of us are hoping for: physicists love nothing more than discovering the shortcomings of their theories, since this is the first step toward more fundamental theories with even more predictive power!”

No, finding the Higgs boson does not answer all the questions of particle physics, much less lend insight into the existence (or not) of God. For that reason, Dr. Krusberg (like most physicists) bemoans the term ‘God particle’ and insists, “There really is nothing either literally or metaphorically god-like about the Higgs boson.” Indeed, one writer for the British journal The Guardian reached such a point of frustration about the name that he ran a competition for alternatives. The winner was “the champagne flute boson,” ostensibly because the bottom of a champagne bottle is an excellent and oft-used demonstration of the energy potential of the Higgs Mechanism. Or then again, perhaps it is simply because physicists thought that finally finding this shy particle would call for some of the bubbly.

On the other hand, some science writers and scientists can appreciate the ‘educational benefits’ of such a mysterious and controversial name because it attracts the attention of the general public and puts a relatable face on an extremely esoteric physics concept. Krusberg herself admits that “People are naturally drawn to the mysterious and the controversial, providing educators with great teaching opportunities.” But she worries about the larger social implications involved in “mixing the vernacular of physics and spirituality,” not least because such uncritical mixing can lead the non-scientific community to draw conclusions about the authority and reach of science that are not justified.

Understanding that the Higgs boson is not the literal stuff of God and that it does not prove or disprove God’s existence (as the name seems to suggest) extinguishes the fire under any sort of religious outcry. But this does not mean that its discovery is irrelevant to the discussion of science and faith, nor to the Christian community as a whole. As Dr. Krusberg remarks, “The recent discovery of [this] new boson at the LHC perfectly embodies the scientific process at its best (and thereby illustrates to the public why and how science works).” Scientific exploration of nature is not a fool-proof endeavor; healthy skepticism and accountability to a wide community of other researchers are absolutely critical to its success. But such evidence of the power and finesse of well-executed science as we saw last week is a testament to our ability to explore and understand the ‘how’ of the universe. God has equipped humanity with the desire, the intellectual abilities, and the collective will to recognize and explore the cosmic order and beauty of his creation. God has made our home knowable, and has given us the tools and capacities by which to know it.



At left, Cern researchers present their findings to a few hundred of their colleagues in Melbourne, Australia. Image © 2012 CERN

It is valuable, then, for the Christian community to understand and appreciate how science works, in part to recognize that there are many instances in which science and the church work in tandem in order to better understand and better serve the world. But I think there is something else we can draw from the story of the Higgs boson, too. The nickname ‘the God particle’ has touched nerves in religious communities because it implies that science has the ability to prove or disprove divine existence by physical means. Even though the physics community is by no means claiming insight into the divine, it is sometimes assumed by the religious community that scientists view their work as chipping away at God’s existence when they begin to understand something that was previously unknown, or known only “by faith” in esoteric theories and models.

And yet, regardless of motives or metaphysical interpretations, perhaps physicists' search for the Higgs boson is in fact an apt picture of our own search for God. How many times have we stared up at the starry ceiling in times of crisis and prayed fervently for some kind of sign from God to assure us of his presence? And how many times has that much-desired evidence appeared only in retrospect, when we look back to see God’s hand faithfully and elegantly working in ways inscrutable at the time? It took a community of physicists to discern the presence of the Higgs boson. But even so, they could only do so after the fact from the cascade of particle decays it sparked; they could not observe the particle itself directly. In a similar way, though we often do not see the working of God directly, “in the moment,” we still trust in his presence and providence, often depending on friends, family and the community of the church to help us see his hand in hindsight.

So while the discovery of the Higgs boson does not itself explain God, we rejoice at the subtle yet striking new insight we have into God’s creative genius via the Higgs boson and at the way God gives evidence of his faithfulness in the ordered creation itself. Perhaps, however, the greatest insight we can glean from this breakthrough is an analogy for the way God calls us to seek him and find him together, in the community of those who follow his son.

Tomorrow, Baylor University physicist Gerald Cleaver answers the question, "What is the Higgs boson?"



]]> Tue, 10 Jul 12 09:02:29 -0700 Faith Tucker http://biologos.org/blog/the-transit-of-venus?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication http://biologos.org/blog/the-transit-of-venus?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication Today we have a chance to witness a special moment in history as Venus transits across the disk of the Sun for people across the world to see. Not only is this process of discovery exciting for natural science, but it has profound theological ramifications as well. Today we have a chance to witness a special moment in history as Venus transits across the disk of the Sun for people across the world to see. This rare astronomical occurrence may have been witnessed by Montezuma in 1520, was first predicted by Johannes Kepler in 1631, launched Captain James Cook’s expedition around the world in 1768, helped us determine the Earth's distance from the Sun in the 1882, and will not occur again until 2117.

The astronomy community is particularly interested in this event because exoplanets throughout the Milky Way galaxy regularly transit their parent stars in just the same way. This local example will allow astronomers to test and refine techniques used to determine the composition of these exoplanets' atmospheres, providing insight into whether these distant planets could possibly harbor life.

As Venus begins to cross in front of the disk of the Sun, Venus's atmosphere will refract the Sun's light, illuminating the backlit portion of the planet's atmosphere. Telescopes on the ground and in orbit will be trained on this thin arc of atmosphere lit up by the Sun. Astronomers will use spectrometers to break the light up into its constituent colors, from which they can determine the chemical composition of our over-heated sister planet's atmosphere. Once perfected, this same technique can be used to examine the atmospheres of planets far beyond our own solar system, offering us one of our best clues as to the habitability of these distant worlds.

Not only is this process of discovery exciting for natural science, but it has profound theological ramifications as well. Surely a God capable of orchestrating both the majestic swirls of a spiral galaxy and the intricate language of DNA could bring forth life where and when He chooses, but only now are we on the verge of being able to answer the age-old question: “Did God confine His creative life-giving actions to our own planet, or does His abundant fertility extent far beyond our limited experience?”

In 1882, William Harkness, the Director of the U.S. Naval Observatory, was one of two astronomers to determine from the transit of Venus the distance from Earth to the Sun. Just as previous viewers could never have imagined calibrating the scale of the solar system from such an event, Harkness could not predict its importance in 2004 and 2012 (the most recent Venus transits). As we look to the future, we can hardly imagine what new frontiers the next Venus transit of 2117 will find us exploring.

"We are now on the eve of the second transit of a pair, after which there will be no other till the twenty-first century of our era has dawned upon the earth, and the June flowers are blooming in 2004. . . . What will be the state of science when the next transit season arrives God only knows. Not even our children's children will live to take part in the astronomy of that day. As for ourselves, we have to do with the present ..." ~William Harkness, the Director of the U.S. Naval Observatory, quoted in 1882 (source: NASA.gov)




The image above shows Venus on the eastern limb of the Sun during the 2004 transit. As described in Tucker's essay, the faint ring around the planet comes from the scattering of light through its atmosphere, which allows some sunlight to show around the edge of the otherwise dark planetary disk. The faint glow on the disk is an effect of the TRACE telescope through which the image was captured. For more on the historical significance of the transits of Venus (including the voyage of Captain James Cook), see this article from NASA, which also includes links to several live webcasts of today's transit.


]]> Tue, 05 Jun 12 11:47:56 -0700 Faith Tucker http://biologos.org/blog/the-wonder-of-the-universe-the-wonder-of-water?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication http://biologos.org/blog/the-wonder-of-the-universe-the-wonder-of-water?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication The water that we take for granted was forged in the nuclear furnace of a star that exploded in the suburbs of the Milky Way galaxy billions of years ago. The Wonder of Water

Large stars near the end of their lives regularly explode. With the force of a billion atomic bombs they strew their contents over unimaginably vast regions of space. It is, of course, a once in a lifetime event for the star—a literal “going out with a bang.” And even though recorded history is just a few thousand years long—and stars live for billions of years—we have some examples of such explosions that were noted by careful observers.

In A.D. 1054 what is now the Crab Nebula exploded in a flash of light bright enough to be seen in daylight for weeks. Astronomers in Korea, China, Japan, North America and the Middle East all recorded the supernova, as it is now called, although Europeans did not. It seems that Europeans, convinced that the heavens were perfect and unchanging, managed to delude themselves into not seeing this new star, which must surely have been quite visible.

The great Danish astronomer Tycho Brahe witnessed another supernova in 1572. Like his predecessors, he could not believe that such a dramatic change in the heavens was possible, but, apparently unlike his predecessors, he had enough confidence in his observations to know that he was seeing something remarkable. Brahe’s protégé, Johannes Kepler, witnessed another supernova in 1604, and then there were no more visible from earth until 1987, when a star exploded in a nearby galaxy known as the Large Magellanic Cloud.

A supernova explosion fills a massive region of space with the elements created inside the star; the powerful explosion, though, follows known laws of physics as it distributes its contents about the universe. A vast cloud of chemically enriched material, trillions of miles in diameter, results from the event—an event absolutely critical for enabling life.

The grand cloud that results from the supernova resembles the original cloud out of which the star formed in the first place, with one important difference—it contains a substantial roster of different materials, and not just hydrogen and helium. This time around gravity has more to work with, beginning again to gather the material in the huge cloud back into balls. The largest chunk at the center becomes another star—one that starts out with heavier elements, in addition to hydrogen. It is the ultimate recycling project, but, unlike recycling on earth, the atoms getting recycled remain in mint condition, no matter how many times they are used.

Some of the smaller balls end up orbiting about the second-generation star. These smaller balls contain many different atoms, and some of them have a curious molecular combination of hydrogen and oxygen. In most parts of the universe these molecules are in the form of a solid. In the others they are a gas. But on balls that are exactly the right distance from the central star, the molecules are liquid, an all-purpose, seemingly magical liquid called water.

Water is found in several places in our solar system. Hydrogen is, of course, the most common element in the universe, and while oxygen is far less common it is readily available to combine with hydrogen and form water. Water in the form of ice is a major component in comets and can be found in trace quantities in the atmosphere of Venus, under the surface of Mars and possibly even on some of Jupiter’s moons.

(We have to keep in mind, however, that more than 99 percent of the mass of the solar system is in the sun, so the distribution of elements elsewhere is almost irrelevant from the perspective of the solar system as a whole. The earth has a lot of water, but the earth is a tiny, insignificant speck compared to the sun. And because the water tends to cover so much of the surface, it is easy to overestimate the total amount. Astronomers are not sure exactly where the water on the earth came from. Constructing the early history of our solar system is an enormous challenge.)

From a purely scientific point of view, water is a molecule like any other—and there are lots of molecules. The laws of physics and chemistry describe its behavior, and there are no deep mysteries embedded in its familiar structure. But the laws of physics and chemistry conspire to make water unusual in ways that are critically important for life. Most peculiarly, water expands rather than contracts when it freezes. This makes ice lighter than water, so it floats. Floating ice insulates the water beneath it from the cold temperatures of winter. Absent this layer of insulation, bodies of water all over the earth would freeze solid. If ice were heavier than water, the layer of ice that formed on the top would sink to the bottom and another layer would freeze on top and sink until the entire body of water was a solid piece of ice. This would kill almost every life form in the water.

Water is also an effective solvent. Waste products from our bodies dissolve readily in water and can then easily be expelled. But wait—as they say on television—there is more. Water is also a remarkable coolant capable of absorbing heat and carrying it away from our bodies in the form of sweat. And water stores heat in our bodies, helping keep us warm in cold weather. Magical.

The creation story in Genesis records that God gathered the waters. In the King James Version that I read as a child it says, “God said, Let the waters under the heaven be gathered together unto one place, and let the dry land appear: and it was so.” In ways that the original readers of Genesis could never have imagined, the gathering of the waters was a cosmic process that took billions of years and involved all the laws of physics and chemistry. The water that we take for granted that covers so much of our planet and makes up so much of our bodies was forged in the nuclear furnace of a star that exploded in the suburbs of the Milky Way galaxy billions of years ago.

That water now cycles endlessly through the life process here on earth—cooling, cleansing and nurturing us. It irrigates our crops, nourishes our livestock, cleans our clothes and gets turned into snow at ski resorts. In those parts of the world where it is plentiful, clean and fresh, we take it for granted and play with it. In Quebec City they construct a hotel out of ice every winter to attract tourists and invite hardy souls to hold their weddings there, wearing parkas and snow boots. We think nothing of using thousand of gallons so our lawns will be green rather than brown in the heat of summer. Water is like air—plentiful and useful.

In parts of the world where fresh water is rare, its value is more apparent. There is a school in Bulawayo, Zimbabwe, where children used to walk a quarter mile during their breaks to get a drink of water. I used to walk to the hallway to get a drink when I was in school. World Vision, one of many organizations helping with water problems around the world, installed a well near the school that the children now use to get water. On school days a group of laughing, happy children can be seen working the oversized pump that takes several of them to manage. The water that emerges from its modest faucet is welcomed in ways that few North Americans can appreciate.

For those schoolchildren, the water is simply a welcome part of their diet and lifestyle now. Some of the children that stay in school and go on to university will eventually discover that the precious fluid—summoned from beneath the earth by a few children cranking on a lever—was created billions of years ago, deep in the heart of a star, via processes of unimaginable subtlety. Those that have learned to worship God will no doubt marvel and give thanks.

Water exists because the universe has a set of laws that guide its steady development from the big bang into the present. If we suppose that water and the life it enables are of no consequence, then we can dismiss these laws as irrelevant. On the other hand, if we believe that God is the creator of life and that life has a purpose, then these laws take on a new character. If God is the Creator, then these laws exist because God created them. And these laws work because God upholds them from moment to moment. Viewed by these lights, the origin of water and life are creation events, intentionally enabled by the Creator of the universe.


]]> Sat, 05 May 12 05:30:09 -0700 Karl Giberson http://biologos.org/blog/southern-baptist-voices-a-biologos-response-to-william-dembski-part-ii?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication http://biologos.org/blog/southern-baptist-voices-a-biologos-response-to-william-dembski-part-ii?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication I now respond directly to Dembski’s analysis of “Darwinism” and how BioLogos differs from the view he critiques. Is Darwinism Theologically Neutral?

With the first part of my essay as background, I now respond directly to Dembski’s analysis of “Darwinism” and how BioLogos differs from the view he critiques. He begins by posing a question, “Is Darwinism theologically neutral?” He goes on to describe two contrasting views:

1. Those of the agnostic philosopher, Michael Ruse, who claims Christianity and Darwinian evolution are compatible and,
2. Those of individuals who hold a young earth view and claim Christianity and Darwinian evolution are incompatible.

Dembski suggests that Ruse, in order to claim compatibility (neutrality), redefines Christianity. I agree he does this. Without belief in the bodily resurrection of Jesus, Christianity is dead and, as Paul says, Christians are of all people most to pitied. (1 Corinthians 15:19).

Dembski also states that a belief in common descent can be consistent with Christian faith (i.e. neutral), and here I agree with Dembski again. As he points out, Christianity is not defined by the mechanism that God chose to use in accomplishing his purposes in creation.

So far we are on exactly the same page. Ruse claims Darwinism is neutral, but only by departing from Christian theology. Some young earth creationists claim Darwinism is not neutral, but they focus on common descent and this, by itself, does not depart from Christian theology. However, as Dembski quickly notes at that point in his essay, he has not yet carefully defined Darwinism and Christianity. He goes on to describe what he considers to be some non-negotiables of each.

Dembski suggests that among the core non-negotiable principle beliefs of Christianity are: (a) divine creation, (b) reflected glory, (c) human exceptionalism, and (d) bodily resurrection of Jesus. I agree that these are non-negotiables; take away any of these beliefs and you no longer have Christianity. We’re still on the same page.

What about non-negotiables of “Darwinism?” They are, he says, (a) common descent, (b) natural selection, (c) human continuity, (d) methodological naturalism. With that, he proceeds to analyze each.

Common Descent

Common descent, which today is at the core of the biological sciences, was a fundamental tenet for Darwin. Dembski sees no significant theological problem with common descent. “By themselves [the Christian non-negotiables described above] allow that God might have specially created living forms or brought them about via an evolutionary process,” he writes. He sees no theological conflict with this Darwinian tenet, even though he does not subscribe to it.

Natural Selection

Dembski indicates that natural selection, as defined by Darwin, is in tension with two of the four Christian non-negotiables—divine creation and reflected glory. His primary concern is that Darwin’s view of natural selection is non-teleological. Insomuch as this is true (and Darwin’s views on teleology are complex and contested), I agree. If Darwin’s non-teleological views were correct, this would be incompatible with some of the non-negotiables in Christianity. As Dembski says, “to say that something is undetectable is not to say that it doesn’t exist....” I concur that Darwin had no scientific basis for concluding that the evolutionary process did not end up exactly the way that God intended in the beginning. If Darwin reached non-teleological conclusions on the basis of his data then he allowed his philosophical and theological commitments to influence his conclusions. Like Dembski, I believe God did call our existence into being; there is a teleological basis for our presence on earth. We are by no means an accident and to the extent that Darwin thought we are, he was wrong.

So far, I see no significant difference between BioLogos and the non-negotiables presented by Dembski. Intriguingly, however, Dembski goes on to state, “it seems odd, given C1—[divine creation], that God would create by Darwinian processes, which suggest that unguided forces can do all the work necessary for biological evolution.” Here we part company. As indicated in my introductory comments above, I believe that the natural activity of God is not less divine than the supernatural activity of God, something borne out by the Scriptures themselves. This does not mean that I think that no supernatural activity occurred in life’s history; I just don’t see why it would be “odd” if God chose to create life’s diversity through his natural activity. How would we know what is odd as it relates to the activity of God? The only reliable source of what is odd and what is not is God’s revelation through his Word. But I see no scripturally-based rationale for determining the expected ratio of natural vs. supernatural divine activity in creation. Scripture is silent on the issue and so far at least, science is as well—other than demonstrating that many biological features and mechanisms previously thought by some to be evidence of supernatural action can now be explained via God’s regular activity—that associated with his natural laws. For the present, I think it is best to withhold judgment about the extent to which God suspends his ongoing regular activity in favor of miraculous supernatural activity in the history of the creating life’s diversity.

I now come to the most fundamental point of disagreement between the Intelligent Design movement and BioLogos. Dembski states:

Given that science is widely regarded as our most reliable universal form of knowledge, the failure of science to provide evidence of God, and in particular Darwin’s exclusion of design from biological origins, undercuts C2 [reflected glory].

Furthermore, he also writes:

If God does occlude his purposeful activity in nature, that raises a tension with (C2), which states that the world clearly reflects God’s glory (Psalm 19) and that this fact should be evident to all humanity (Romans 1).

I don’t think that God occludes or masks his activity. Thanks in no small part to science, we now recognize that there are “signposts” (C.S. Lewis’s term) all over the place directing our attention to the existence of our Creator. The question is whether those “signposts” can be developed into scientific hypotheses that can be scientifically tested in a manner that parallels how one goes about testing the hypothesis that smoking causes cancer or that DNA is the genetic material. The heavens do declare the glory of God (Psalm 19), and, “ever since the creation of the world, his eternal power and divine nature, invisible though they are, have been understood and seen through the things he has made” (Romans 1:20). God has not occluded his activity. It is all around us. From the birth of a baby to the birth of a star; from a universe which is mathematically coherent to one which is exquisitely fine-tuned; from our sense of shame to our ability to recognize the good and the right—from all of these and so much more, we see signposts all pointing to our Creator. Individually each hints at something beyond ourselves. Together they shout out with the message of God’s glory. Still, can they be tested scientifically—in a manner that parallels whether penicillin kills bacteria or the mitochondrion is the cell’s energy factory—to determine whether God is at work in them? Can intelligent people who choose not to believe come up with feasible alternative explanations that do not include God? Sure, they do it all the time and, as Romans 1 tells us, they have been doing it from the beginning of human existence.

Given the way that God has worked through his regular natural activity, why should we expect to be able to develop a test for the activity of God? God is always active, but scientific testing of God’s activity would require a “control” where God is not active. How can we conduct an experiment which studies the “presence vs. absence of God” when God is always present as sustainer as well as creator?

Human Continuity

Dembski quotes from Darwin’s Descent of Man:

The difference in mind between man and the higher animals, great as it is, certainly is one of degree and not of kind. We have seen that the senses and intuitions, the various emotions and faculties, such as love, memory, attention, curiosity, imitation, reason, etc., of which man boasts, may be found in an incipient, or even sometimes in a well-developed condition, in the lower animals.

Even if all that Darwin says here were more or less true, it would still say nothing about that which makes humans truly exceptional, because—our linguistic and cognitive abilities aside—what makes us truly exceptional has less to do with biology than with the fact that God chose to enter into a unique relationship with humankind. Dembski paraphrases an ideologically strict Darwinian view of man as "not worthy of special divine attention, and with no prerogatives above the rest of the animal world." But Christians recognize that our material ordinariness is radically transformed by the presence and promises of God. Exactly as with the people of Israel among the nations, so humans among the animals: our special identity rests in the free choice of the Creator to give us his himself and his name. If we recognize that human specialness rests on God’s fellowship with and call upon us, and that we—alone of all creatures—are enabled by God to bear his image in the world, then anything Darwin said about the physical continuity between humans and animals is irrelevant. In the way that matters most, we are not continuous with animals. For philosophical and theological reasons, Darwin did not recognize this. Darwin, I believe, was wrong. I, like Dembski and like Southern Baptists in general, am not a Darwinist.

Methodological Naturalism

Dembski defines methodological naturalism in the following way:

The physical world, for purposes of scientific inquiry, may be assumed to operate by unbroken natural law.

He goes on from there to write that if one assumes that miracles were performed in salvation history, then it would seem to be arbitrary to assume that God would not also perform miracles in natural history as well. Although I do not rule out the occurrence of miracles in natural history, the purpose of miracles in the biblical narrative seems to stem from God’s desire to reveal himself to humankind, reminding us of and guiding us in our relationship with him and each other. Given that, I do not see why it is arbitrary to think that God may not have used miracles to accomplish his purposes in nature before humans were around to observe them.

However, I strongly disagree with Dembski that if one believes God has worked primarily through natural processes in creation as a whole, this makes belief in the resurrection less tenable. The two ought not to be tied together in this way, especially since I have already stated that I reject the notion that the ordinary and regular processes of creation are any less God’s—than what I have called supernatural processes. One’s conclusion about the mechanism of creation has no logical extension to one’s views about the historicity of the bodily resurrection of Jesus.

In conclusion, I think Dembski takes some steps that are both theologically unnecessary and scientifically unjustified in rejecting what careful study tells us about God’s marvelously ordinary processes of creation: ordinary because they follow his natural laws so faithfully, marvelous because they have resulted in a world of complex and beautiful life. On the other hand, I agree with Dembksi that Darwin’s views were not theologically neutral. Darwin’s views on teleology, human exceptionalism, and miracles were not compatible with Christianity. Quite simply, this is why I do not consider my views to be Darwinian and why I am not a Darwinist.

For further reading:

The BioLogos website offers many resources to acquaint readers with the incredibly strong scientific evidence for common descent and other facets of evolutionary biology.

See Understanding Evolution: An Introduction to Population and Speciation, by Dennis Venema (note the link to other articles in this series on the right hand sidebar), and Evidences for Evolution, by David Kerk. Also, for three very fine podcasts, consider viewing these posts by Kelsey Luoma.
]]> Thu, 03 May 12 13:12:04 -0700 Darrel Falk