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.

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.

Belief in God in an Age of Science

Introducing John Polkinghorne

An Englishman of Cornish descent, John Polkinghorne was born in 1930 in the coastal town of Weston-super-Mare, southwest of Bristol in North Somerset. Although his parents had three children, an older sister died in infancy and his older brother, who served in the RAF Coastal Command during World War II, died when his plane was lost over the North Atlantic on a stormy night in 1942. Effectively an only child from that point on, his family nurtured him in their Christian faith, leading him to say a few years ago, “I cannot recall a time when I was not in some real way a member of the worshipping and believing community of the Church.”  (From Physicist to Priest, p. 7)

At the same time, his gift for mathematics did not go unnoticed, resulting in several years of study at Trinity College, Cambridge (where Isaac Newton had lived and worked in the seventeenth century). As an undergraduate, Polkinghorne studied applied math rather than pure math, a typical choice for someone interested in physics. There, he formed a close friendship with a classmate, Michael Atiyah, who would be best man at his marriage in 1955 to another mathematics student, the late Ruth (Martin) Polkinghorne. Later knighted, Sir Michael was President of the Royal Society in the early 1990s, the same period when Polkinghorne was president of Queen’s College, Cambridge.

​Sir Michael Atiyah (Source)

Polkinghorne was particularly inspired by the course in quantum physics taught by Paul Dirac, whom he has described as “undoubtedly the greatest British theoretical physicist of the twentieth century,” an opinion with which it is hard to disagree. For Polkinghorne, Dirac’s lectures were simply unforgettable: “so profound was the material, and so closely structured was the argument, that one was carried along enthralled by the experience.” (From Physicist to Priest, p. 26)

Paul Dirac (Source)

Remaining at Cambridge for graduate study, Polkinghorne worked under the Pakistani physicist, Abdus Salam, who later became the first Islamic scientist to win the Nobel Prize, which he shared with Americans Sheldon Glashow and Steven Weinberg for contributions to unifying the electromagnetic force and the weak nuclear force. Then he did postdoctoral work at Caltech with Murray Gell-Mann, another future Nobel laureate for his work on quark theory, and attended the famous lectures by yet another future Nobel laureate, the late Richard Feynman.

After Caltech, Polkinghorne taught briefly at Edinburgh before returning to Cambridge, where he was soon elected to a new professorship in mathematical physics. Quantum mechanics (QM) is his specialty; his writings on both QM and its interaction with theological ideas are numerous. His book, The Quantum World, has sold more than 100,000 copies, and when Oxford University Press wanted a book on this topic for their highly successful series, “A Very Short Introduction,” it was Polkinghorne who wrote it. His former students include Nobel laureate Brian Josephson, “the most precociously brilliant undergraduate that I ever taught,” and Martin Rees, who was until recently President of the Royal Society.

Although Polkinghorne has never won a Nobel Prize, in 1974 he was elected Fellow of the Royal Society, the highest honor in British science. Three years later, at the top of his scientific career at age 46, he astonished his colleagues by announcing a decision to pursue ordination as an Anglican priest; two years later, he resigned his chair at Cambridge to enter seminary. Partly, he felt played out. As a former physics student myself, I do not find his diagnosis hard to accept: “In mathematically based subjects you do not get better as you get older. Somehow one needs mental agility more than accumulated experience, and it becomes progressively harder for an old dog to learn new tricks. It is unlikely that most people do their best work before they are 25, but most do before they are 45.” Or, to put it more succinctly, “I simply felt that I had done my little bit for particle theory and the time had come to do something else.” (From Physicist to Priest, p. 71)

Nevertheless, he also felt a genuine call to the ministry, for “Christianity has always been central to my life” and ‘becoming a minister of word and sacrament would be a privileged vocation that held out the possibility of deep satisfaction.” (From Physicist to Priest, p. 73) After seminary, Polkinghorne served as a parish priest for many years and later as canon theologian of Liverpool Cathedral. He was knighted in 1997—although, as an ordained minister, he declines to use the title, “Sir John Polkinghorne”—and was awarded the Templeton Prize in 2002. It has been altogether a life well lived for the kingdom of God.

Looking Ahead

I’ll return in about two weeks with a summary of Polkinghorne’s basic attitudes toward science and religion, which (in his view) have a “cousinly” relationship. In the meantime, readers are invited to read Zeeya Merali’s essay, “The Priest-Physicist Who Would Marry Science to Religion,” from the March 2011 issue of Discover magazine, and “An interview with John Polkinghorne,” by philosopher Paul Fitzgerald.

References

John Polkinghorne, From Physicist to Priest: An Autobiography (2008).

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).

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.

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

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 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.

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?"

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.

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.

I ask the question, “Why is the universe so special?” Now scientists don’t like things to be special; we like things to be general, and our natural anticipation would have been that the universe is just a common or garden specimen of what a universe might be like.

But we’ve come to understand a lot about the history of the universe. We know that our universe started 13.7 billion years ago, and it started extremely simple, just an almost uniformly expanding ball of energy, about the simplest physical system you could possibly think about. But a world that started so simple has of course become rich and complex. With you and me, in fact, the most remarkable and complex consequences are its history, at least of which we are aware. The human brain is far and away the most complicated physical system we have ever encountered anywhere in our exploration of the universe.

That fact itself might suggest that something has been going on in cosmic history rather than just one thing after another. But we’ve also come to understand many of the processes by which this rich fruitfulness has come to birth. As we’ve come to understand these, we’ve come to see that though these processes are of course evolving processes, they took long periods of time – the universe was 10 billion years old before any form of life appeared in it, at least as far as we know anyway – and life of our complexity only appeared yesterday.

Nevertheless, the universe is pregnant with life, pregnant with the possibility of life, essentially from the beginning onwards. By which I mean the given laws of nature had to take a very specific, very finely tuned form, if the universe was to have so fruitful a history.

That’s a very remarkable discovery, and let me give you some examples of why we believe that. If you’re going to have a fruitful universe, one of the first things you have to get right is that you have to have the right stars in the universe. The stars are going to have a very important role to play. First of all, you must have some stars that are going to be very long lived, live for billions of years, steadily burning, steadily producing energy which will enable the development of life on one of the encircling planets. We understand what makes stars burn in that sort of way very well, and it depends on a delicate balance between the strength of gravity and the strength of electromagnetism. Electromagnetism is the force that holds matter together. The seats on which you are sitting are held together by electromagnetism and in fact you are held together by electromagnetism.

If you alter that balance a little bit in one direction the stars will begin to burn intensely, furiously, just pouring out energy and they will only live a few million years rather than a few billion years. If you move it a little bit in the other direction they will burn so slowly they will be brown stars and they will not produce enough energy to fuel the development of life. So you have to have a very delicate finely tuned balance between the strength of gravity and the strength of electromagnetic forces in a fruitful universe.

Remember, science takes the laws of nature, takes the given strengths of gravity, the given strength of electromagnetism, uses that to explain processes in the world, how things happen, but it doesn’t explain where those laws of nature come from. They are just brute facts as far as science is concerned.

And the stars have another absolutely indispensible role to play. The stars are the place where the heavier elements essential for life are made in the interior nuclear furnaces. There are many elements that are necessary for life, of which carbon is perhaps the most essential. Carbon is the basis of the long chain molecules, which are the biochemical basis of life. The early universe only makes the simplest elements; it makes hydrogen and helium and it makes no carbon at all. Carbon only begins to be made when the universe, which started uniform, begins to condense and become lumpy and grainy with stars and galaxies. As the stars condense they heat up, nuclear processes begin again in their interiors. And it’s those nuclear processes in the stars that make carbon and the heavier elements. Every atom of carbon in your body was once inside a star. We are people of stardust made in the ashes of dead stars.

And that’s a very beautiful process that takes place in that sort of way. And one of the great triumphs of astrophysics and the second half of the 20th century was to unravel that process. One of the people who did some of the most important work on that was a senior colleague of mine in Cambridge called Fred Hoyle. And they were trying to figure out how to make carbon. They got helium, and if you can make three helium nuclei stick together that will produce carbon, but when you have something as small as a nucleus it is impossible to get three to stick together at one time, they’re just too small.

Ok, so let’s do it step by step. Stick two together gives you berylium. Helium 4 gives you beryllium-8, hope it stays around for a bit, another helium comes along, attaches itself, and bingo, you’ve got carbon-12. That’s the obvious thing to think about but it doesn’t work in the obvious way, and the reason it doesn’t work in the obvious way is that beryllium-8 is terribly unstable. It doesn’t oblige you by staying around long enough to catch that third helium, at least in an ordinary, straightforward way.

But Fred realized that it would be just possible for this to happen if there was a very large enhancement effect, in the trade we call it resonance, occurring in carbon at just the right energy, it has to be the right energy, which would enable that attachment process to catch that third helium much much more quickly that you might have thought, in fact so quickly that some of them would get caught before the beryllium-8 disappeared. It was a very good idea, and he must have felt pretty pleased with himself and he went off to just check in the nuclear data tables of this particular resonance’s energy levels, and it wasn’t in the tables, but he knew it must be there, he’s carbon based life like you and me.

So he rang up some friends in the States, a father and son team who were good experimentalists and he said, “Look, you missed something. There’s a resonance and energy level in carbon that you haven’t spotted, and I’ll tell you exactly where to look for it. I know exactly where this energy has got to be. You go look for it.” And they said, “No, no, we don’t want to do that, we have more interesting things to do.” But Fred was very determined and he bullied them into looking for it and they found it.

Now that’s a wonderful achievement, to predict an energy level in carbon on the basis of how it might have been made in the stars is a fantastic scientific achievement. But it’s more than that. Fred had a lifetime conviction of atheism, realized of course that if the laws of physics had been just a little bit different that resonance wouldn’t have been there, and the possibility of carbon-based life is too significant for it just to be a happy accident in his view, so he says in a Yorkshire accent that is beyond my power to imitate, he said that the universe is a put-up job. Fred didn’t like the word God, and so he said some Intelligent, capital “I” Intelligence, must have monkied with the laws of nature to make carbon production possible. What that could possibly be I don’t know, but the more sensible thing to say is that creation is ordained, that the laws of nature would be such, as to enable the fruitfulness of carbon-based life.

We’ll come back to evaluating that possibility in a minute, but before we do, let me give you two other examples of how specific, how special, our universe has to be for us to be able to be here today to think about. We live in a universe that is immensely big, beyond our powers to imagine really. There are a hundred thousand million stars in our galaxy in the Milky Way, of which our sun is just a common or garden specimen, and there are about a hundred thousand million galaxies in the observable universe, of which our Milky Way is a pretty common or garden specimen. So we live in a world that is unimaginably vast, and sometimes we might feel upset by that and think, “What could be the significance of us who are simply inhabitants of a speck of cosmic dust, as you might say, in this vast, vast universe?”

Nevertheless, if all those stars were not there, we would not be here to be upset at the thought of them. Because there is a direct connection between how big a universe is and how long it lasts, and a universe that is significantly smaller than our universe would not have been able to last the 14 billion years, which is the necessary time to produce beings of our complexity. So that’s another condition of the world that has to be right for human beings, or something like human beings, to be a possibility.

One final example, which is the finest tuning of all: quantum theory suggests that there should be an energy attached to space itself. In quantum theory the vacuum, so called empty space, is not just a void. There are things called vacuum fluctuations which occur in a continual sort of seething mass of things coming into being and going out of being all the time. So while there is nothing there that doesn’t mean there is nothing happening. That may sound strange and paradoxical but believe me that’s what quantum theory implies. And of course these happenings, these fluctuations, generate a certain amount of energy, we call it “zero point energy”, and that energy is spread out over the whole of space. So we expect there to be energy associated with space.

And just recently the astronomers have discovered something called dark energy which is driving the expansion of the universe, which is just such an energy associated with space. Well that’s very good, you might say. However, when we estimate, just from thinking about quantum theory, how much energy there should be in space it turns out to be a fantastically large amount, and when we see the amount of energy there actually is per volume in space, it turns out to be very, very small in relation to that expected size. In fact, it turns out to be smaller by a factor of 10^-120. That means by a factor of 1 over 1 followed by 120 zeros. You don’t have to be a great mathematician to see that’s a fantastically small number. So some fantastic cancellation has taken place to turn that big number into the tiny number that we actually observe, and if it hadn’t taken place we wouldn’t be here to observe it because significantly higher energy would simply have blown the whole show apart too fast for anything interesting to happen. That’s the finest tuning that we know in the universe: one part in 10¹²⁰.

So we live in a world that is very remarkably finely tuned, and we have to consider that. And all scientists would agree about what I have been telling you; this is non-contentious. Where the contention comes in is what we might make of that, what is the further significance of it.

In the conclusion to Dr. Polkinghorne’s lecture, he looks at two explanations for the "fine-tuning" principle -- the multiverse theory and the existence of a divine intelligence -- and explains why natural theology alone is not sufficient to make the case for a God who interacts and cares for his creation. To make the case for theism, he argues, we need revelation, God's self-disclosure. This is manifest in various ways, including that which we experience personally, including ethics and aesthetics.

“The heavens,” wrote the psalmist “declare the glory of God.” (Ps 19:1 NIV)

The universe that inspired the psalmist three thousand years ago grows grander as each new generation of astronomers adds yet another layer of understanding. Each new discovery pushes back the boundary that separates the known universe from the vast terra incognita that beckons and teases us to keep going, to sail ever further from familiar shores.

A few centuries ago the great philosopher Immanuel Kant repeated the psalmist’s declaration: “Two things fill the mind with ever new and increasing admiration and awe, the more often and steady reflection is occupied with them: the starry heaven above me and the moral law within me. Neither of them need I seek and merely suspect as if shrouded in obscurity or rapture beyond my own horizon; I see them before me and connect them immediately with my existence."

The night sky still beckons us, as it once did the psalmist. I spend time each summer at a rustic family cottage in the wilderness of my native New Brunswick, Canada. There, miles from electricity, the night sky does not compete with artificial light. Smog does not obscure it. Planes do not draw white trails on it. It does not compete with cable television or even cell phones, silenced by the absence of signals. The night sky is simply there, quietly declaring the glory of God. Its many lights reflect off the ripples of the lake, and are accompanied by the rustling of leaves and the voices of the many creatures that call this wilderness home. Only a jaded soul could sit by that lake and not wonder if there wasn’t some larger meaning to the experience.

I can see what the psalmist saw and rejoice as he did. But I watch the night sky through the eyes of a twenty-first century scientist. I have the benefit of centuries of scientific advancement and can see, in my mind’s eye, so much more. Those visible stars are just the advance guard of an almost infinite army of stars going back almost forever. The stars are not attached to a dome that one might reach with an ambitiously tall tower or puncture with a long-range missile. They are so far away that their light has been traveling at unimaginable speed for years, centuries, milennia and longer. The light from the stars in the Hyades Cluster began its journey to the earth at about the time that my ancestors—Loyalists from Pennsylvania—began their journey to this part of North America in the eighteenth century. The light from the closest stars, the trio that make up Alpha Centauri, takes over four years to reach earth. The most distant star ever detected from the earth is a “gamma ray burster” that launched its signal almost 13 billion years ago, when the universe was young. The powerful gamma ray signal from this star began its journey before our planet was even formed, reaching the earth in April 2009.

The psalmist did not know that the stars were made of hydrogen and helium. He did not know they generated their energy through nuclear fusion or that many of them explode at the end of their lives. He knew nothing of galaxies and the layers of structure in the cosmos. He did not understand how fast light travels or that the light from our sun powers photosynthesis and many other processes here on the earth.

The universe brought into view by science is like a collection of Russian matryoshka dolls nestled one inside the other. With the psalmist we can see the outer layer—and it is grand. But inside are additional layers, each one with a new type of grandeur. And at the very end of the unpacking lie the remarkable laws of physics that keep the earth orbiting about the sun, the sun shining reliably, and the sunlight providing energy to sustain life on our planet.

The universe as we understand it today inspires awe. And for those open to its message—from the psalmists of yesteryear to the believers and even the thoughtful skeptics of today—it speaks of a Creator. Our universe does not look like a cosmic accident, where lots of stuff just happened. It looks like the expression of a grand plan—a cosmic architecture capable of both supporting life such as ours and of inspiring observers like us to seek out the Creator.

This is why Antony Flew—“world’s most notorious atheist”—changed his mind and started believing in God.

Dr. Owen Gingerich is professor emeritus of astronomy and history of science at Harvard University. He grew up in a Christian home and attended a Christian college in northern Indiana that had a motto of “Culture for service”, something that was very important in thinking about what he might do with his life.

When it came time to go to graduate school, one of his science professors told him “If you feel a calling to go to astronomy, you should give it a try, because we shouldn’t let atheists take over any particular field.”

And so he went on to a career in astronomy. In the late 1980’s, Dr. Gingerich had a unique opportunity to give a lecture at the University of Pennsylvania on the topic of science and Christian faith. Since then, he’s been trying to help people better understand God’s creation. For example, God could have made the universe in many different ways, but given the particular way it appears, it suggests that we wouldn’t be here if the universe were not very, very old, because out of the big bang came hydrogen and helium, but not oxygen and the iron we need for our blood, for instance. Those things came from the interiors of giant stars and had to cook for long, long periods of time before we got those elements abundant enough for sustainable life. It’s a marvelous picture, and Dr. Gingerich is actively involved in telling people about it.

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.

By the time I was ten years old, I was already determined to follow a career in physics and cosmology, both because of the wonder I felt for the natural world and as a means to better resolve serious questions that were developing within me regarding the relationship between biblical interpretation and scientific discovery. The prior year I had read and studied scripture in its entirety for the first time, rather than just the piece-meal sections covered in my Sunday school classes. Whenever I look back at that year in my life, I am always glad I chose to study the New Testament before the Old Testament, rather than vice versa. From the New Testament study, I found salvation and accepted Christ into my life. But my examination of the Old Testament that followed raised serious questions for me, particularly regarding Genesis. Even as a ten-year-old, I could see the apparent conflict between Genesis and what I had already learned about the history of the universe, of earth, and of life on earth as reported by science. From science I felt amazement and wonder toward God as Creator and strongly desired to learn more about the physical laws set up by God that sustained the universe. In contrast, both of the Genesis stories of creation seemed simplistic and hollow.

As I continued to study, I came to believe that divine inspiration of scripture does not exempt scripture from portraying human authors’ limited (in particular, finite) understandings of the physical world.

Since Genesis 1 and 2 were written in a pre-scientific age, we should expect a non-scientific description of the creation process. Divine inspiration allowed the language of the time to express eternal truths regarding some aspects of God’s nature as Creator. Using stock images from the culture, the opening chapters of Genesis describe God as the ultimate Creator of all things and in charge of all things. These chapters should not be misinterpreted as scientific treatises describing the actual physics processes by which God creates all things.

From further study I came to understand that for almost two thousand years, many others far more knowledgeable than I had wrestled with the same issues. I was thrilled to learn that the early church fathers had developed a procedure for dealing with disagreement between scripture and scientific understanding. In 1657, the famous scientist, mathematician, and devoted Christian, Blaise Pascal, summarized the procedure of St. Augustine and Thomas Aquinas in his Provincial Letters:

When we meet with a passage even in the Scripture, the literal meaning of which, at first sight, appears contrary to what the senses or reason are certainly persuaded of, we must not attempt to reject their testimony in this case, and yield them up to the authority of that apparent sense of the Scripture, but we must interpret the Scripture, and seek out therein another sense agreeable to that sensible truth.... And as Scripture may be interpreted in different ways, whereas the testimony of the senses is uniform, we must in these matters adopt as the true interpretation of Scripture that view which corresponds with the faithful report of the senses.

An opposite mode of treatment, so far from procuring respect to the Scripture, would only expose it to the contempt of infidels; because, as St. Augustine says, “when they found that we believed, on the authority of Scripture, in things which they assuredly knew to be false, they would laugh at our credulity with regard to its more recondite truths, such as the resurrection of the dead and eternal life.” “And by this means,” adds St. Thomas, “we would render our religion contemptible in their eyes, and shut up its entrance into their minds.

During my teenage years, my conviction that science could be used to inform scripture and clarify our understanding and interpretation of it continued to solidify. I agreed with Galileo that, “the Bible tells us how to go to heaven, not how the heavens go.” Further, since God is the creator of all things, the physical and the spiritual, I came to understand that science as the study of the physical and theology as the study of the spiritual must be mutually consistent when both are properly understood. Inconsistency could only be the result of human misunderstanding of one or both arenas of knowledge.

(Some might correctly point out that science is not always as clear-cut as reason plus the report of the senses. That is, at times science also involves debates between competing interpretations, especially on the cutting edge of research. Nevertheless, ongoing scientific investigations gradually winnow away many or most proposed scientific descriptions of a given physical process, leaving only one or a few as the viable candidates. Scientific theories are formed by the general consensus of the scientific community based on overwhelming supporting physical evidence.)

In high school, I faced a serious medical problem, eventually identified as a brain tumor. Surgery was successful, in part due to a positive change in the tumor. In thankful response to God, I decided to pursue a career in church ministry. I determined a primary goal of my ministry would be to help the members of my future congregations develop mutually consistent and mutually supportive understandings of scripture and of science. I chose to attend Valparaiso University in Indiana, where I could, in addition to being a pre-seminary student, also double major in physics and mathematics to increase my scientific knowledge. Over the course of my four years at Valparaiso, I realized that my calling wasn’t for a church ministry, but one aspect of it would be to minister to Christians as a professional scientist, demonstrating by example that faith and science need not be at odds.

Thus, by way of a curved path, I did indeed follow the vocation I had initially chosen twelve years earlier. I decided once again to pursue the path that made my heart sing: studying the underlying laws and forces of the physical universe. As I was deciding which Ph.D. programs in elementary particle physics and cosmology to apply to, I became aware of a new, quickly developing subfield of particle physics called string theory that offered the possibility of unifying all of the known forces and matter in the universe into a single theory. I am now a successful scientist in this area, publishing discoveries that add to our understanding of particle physics and the universe.

In the next installment, Gerald Cleaver offers his advice to fellow Christians on how to seek after a consistent Christian worldview in which scientific and theological understandings of the universe are viewed as mutually supportive and complementary.

When astrophysicist Dr. Jennifer Wiseman first published the following posts as a paper in the BioLogos Scholarly Essay series, the essay’s subtitle asked the question, “Can Recent Scientific Discovery Inform and Inspire Our Worship and Service?” Over the next few weeks, we will look at Dr. Wiseman's answer to that query—an emphatic “Yes!”. But in this first installment we begin by describing some of the reasons such a posture of worship through science is not more common in the contemporary church than it already is.

Oh Lord My God, when I in awesome wonder, Consider all the worlds Thy hands have made; I see the stars, I hear the rolling thunder, Thy power throughout the universe displayed.
Then sings my soul, my Savior God, to Thee; How great Thou art, how great Thou art

(Carl Boberg, 1885; Trans. Stuart Hine 1949)

The words of this great hymn convey the proper overwhelming sense in which the wondrous Creation of God should translate directly into a response of awe and praise from mind, body, and spirit. The writer sees and hears the wonders of nature with his body, considers with his mind what all this implies, and responds with songs from his soul.

But is this worshipful response happening in our Christian congregations today? I believe this kind of response to the Creation can and should happen within the hearts of God’s people and wherever congregations of believers are gathered. Such power can even unify believers who differ on lesser matters as we all look up outside of ourselves at the same wonders and respond with the same praise. As an astronomer, I have felt the sense of being “blown away” by seeing images of countless distant galaxies, or even by just looking up at the array of stars overhead on a dark moonless night and sensing something of the “big-ness” of God.

There are impediments to realizing the fullness of this kind of worship experience for many Christian congregations today. I believe four of the main culprits are ignorance, distraction, controversy, and uncertainty.

Let me start with the first, and clarify up front that by ignorance I am simply referring to being uninformed, rather than the sometimes more negative connotations of the word. How up-to-date is the scientific knowledge of average, educated, committed evangelical church members and pastors?Americans, both adults and schoolchildren, are not ranking favorably compared to the rest of the world’s developed nations in science knowledge these days. We enjoy our technological achievements and resulting gadgets, but true comprehension of scientific principles and recent discoveries is not a strong part of our culture and national conversation these days.

This is reflected directly in what kinds of things are (and are not) discussed in church. In my own generally very good church experience growing up in mainstream America, I can only remember science and nature being discussed in a general way (e.g., we should look at the beauty of flowers and mountains and animals and thank God), except for once in a specific way in a children’s sermon (where we were told we should not believe we came from monkeys!). That was a while ago, but how are science issues handled today? Do pastors speak about the evidence from cosmic background light for a spectacular beginning to the universe? Are the genetic codes being mapped out for animals and humans resulting in praise for God’s amazing “blueprint”? Are the advancements in nanotechnology and biotechnology and medicine subjects for discussion of good and poor uses of technology in church? The answer to these is, of course, “no”, for the most part, yet even issues seemingly more relevant to the daily lives of parishioners are often driven by current technology and scientific advancement, and an informed congregation can better understand how to praise, pray, discern, dialogue, and serve.

Related to being uninformed is the condition of distraction for many evangelical Christians today. The distractions of overloaded schedules, pressured jobs, divided families, and even church environments of entertainment-based worship and activities can impede a lifetime of quiet listening, learning, and contemplation. If there is no encouragement from church leaders to learn and incorporate nature and current scientific discovery into contemplation and praise and service, then there will be no space available in the lives and activities of congregants for what should be the resulting awe and praise.

But what does it mean to be informed about science in today’s evangelical congregations? Too often this has implied a direct relation to controversy, the third reason science is not often inspiring worship these days. There are many voices trying to “inform” Christians about science, and for the average evangelical congregant, discernment about which authority figure to believe can be difficult. Many times Christians are presented with a clear and strong implication that scientific conclusions, especially on issues related to origins of the universe and of life, are part of the secular “World” camp rather than the camp of “God’s Truth”. And Christians “know” that they must be on one side or the other of this stark line of worldliness. Often in more conservative churches a teaching will come from the pulpit that goes something like this: “Scientists tell us that *...+, but they cannot give a reason how *...+ happened; but WE know how: God is responsible!” Therefore any serious consideration of a scientific understanding of the development of the universe and life implies that one is “compromising” the teaching of the Word of God, rather than studying the details of how God works. In Scripture, however, never is the study and experience of nature seen as somehow antithetical to knowing and following the Lord; just the opposite in fact!

This often boils down to the correct interpretation of Scripture. Through sermons, radio spots, television shows, and literature, evangelical Christians are hearing adamant messages conflating the acceptance of modern scientific discovery with worldly compromise, or else providing alternative ideas that are not entirely satisfying. From Young-Earth Creationists, they hear that a literal reading of the Biblical creation account is the only correct one, so all scientific discovery must be reinterpreted to fit a recent Creation. But this robs them of the sense of awe we glean from the magnitude of space and time revealed by astronomy, geology, and fossils. From the Intelligent Design community, they hear the message that life (and perhaps the entire universe) is too complicated to develop through natural processes alone, and therefore that God’s work requires miraculous inputs of information into the natural world. This implies that somehow natural processes must not be fully God’s processes, or that God’s work through them is somehow inadequate. They also hear the message to “teach the controversy,” so that somehow by proclaiming that there is a controversy about natural processes as an adequate explanatory tool for natural history, the controversy will in fact become real. They are then surprised to find out from either advanced scientific study or from the Evolutionary Creation voices that in fact there is no great controversy in the scientific community about the basic structure and timeline of the natural history of the universe and life; that in fact there need be no theological debate about how God brought (and is bringing) the universe and life into being, rather, the issue is whether God is in fact real and responsible for all we know and are. And yet even this unifying message can sometimes seem to gloss over the central theological issues of suffering and death and fallen-ness in Creation. So every approach to origins and evolution evokes some difficulties and challenges with which the Christian congregant must grapple.

Next week, Part 2 concludes Dr. Wiseman's discussion of the stumbling blocks that can stand between the church and its appreciation of science as a means of worship, and turns to the ways that the pursuit of God through study of the created world can help overcome those difficulties by pointing us directly to the Lord.

Evolution: just a theory

One game that my (young) children like to play is a guessing game where both players select a character from among many choices, and by process of elimination, tries to guess the character the other has selected. Questions like “does your character have red hair? glasses?” etc., are used to narrow down the possibilities. Once you have guessed correctly which character your opponent has selected, you can perfectly predict the answer to every question thereafter (and a good many parents likely prolong the questioning to keep the hopes of victory alive for their children). When considered separately, the individual features of each character—glasses, brown hair, purple hat, and so on—mean almost nothing, since they could be features shared with other characters in the game. Only the convergence of multiple features is indicative of a good guess, and the accuracy of that guess is put to the test every time a new question is asked.

A good theory is something like this: an educated guess, based on and consistent with all past work on the topic to date. It allows you to predict how future tests should pan out. In the guessing game, there are limited options to choose from (so the analogy, like all analogies, eventually breaks down). In science, we don’t really know the true way things actually work. What we have are theories—broad explanatory frameworks supported by experimentation, that make sense of our current collection of facts—that we can use to make testable predictions about the natural world. All theories in science are provisional in that they are not complete descriptions of how the world actually works and are subject to future revision; but at the same time they are robust frameworks that can be used to predict how experiments should behave with almost boring regularity. So, far from the colloquial usage of “theory” as speculation, “just a theory” is high praise in science.

The current understanding of evolutionary theory in all its scope and diversity is far more complex than Darwin himself could have ever envisaged. (As a geneticist, I’ve often wished I could have a cup of tea with him to show him how far his theory has grown, especially given his confusion about how heredity worked.) Our understanding of how evolution works has grown by leaps and bounds since the 1850s. What is remarkable is just how much Darwin got “right” given his time and place. His main hypotheses—that species descend from ancestral forms through descent with modification, that and natural selection acting on heritable variation is a significant force in that process—remains the core of modern evolutionary theory. We’ve added a lot of detail since then (population genetics, kin selection, neutral evolution/genetic drift, symbiosis, horizontal gene transfer, molecular exaptation, and so on), but Darwin’s core ideas have produced a wealth of successful predictions. They were a very good “guess” that continues to pay rich scientific dividends.

Whale evolution: an example of converging lines of evidence

One of the things I personally find quite enjoyable about evolutionary theory is the counter-intuitiveness of some of the predictions it makes. One example that is a personal favorite, and one I often use to illustrate how evolution makes sense of converging lines of evidence, is cetacean (whale) evolution. Let’s set up the “problem” that evolutionary biology forces upon us:

• Modern cetaceans are mammals – they nourish their young in utero through a placenta, give birth to live young, and feed newborns with milk – all features of standard mammalian biology.
• Mammals are tetrapods – organisms with four limbs. Mammalian life shows up in the fossil record as an innovation within tetrapods, so mammals are “nested within the set” of tetrapod forms. Not all tetrapods are mammals (amphibians, for example) but all mammals are tetrapods.
• Tetrapods are by and large terrestrial creatures. Having four limbs for locomotion is a distinctly land-based adaptation.

The “problem”, of course, is that modern whales are emphatically not terrestrial, nor do they have four limbs – they have two front flippers and a tail, with no hind limbs in sight. Yet they are mammals, which forces evolution’s hand as it were. Evolution thus is dragged, under protest, to the prediction that modern whales, as mammals, are descended, with modification, from ancestral terrestrial, tetrapod ancestors. Instantly this prediction raises a host of uncomfortable questions: where did their hind limbs go? How did they acquire a blowhole on the top of their heads when other mammals have two nostrils on the front of their faces? How did they transition to giving birth in the water? What happened to the teeth of the baleen whales? What happened to the hair characteristic of mammals? and so on. In some ways, evolutionary thinking about whales creates more difficulties than it appears to solve.

And yet, these difficulties are the stuff of science. If indeed our “educated guess” of terrestrial, tetrapod ancestry for whales is correct, the evidence will show that these transitions, challenging though they may seem, did indeed occur on the road to becoming “truly cetacean”.

Going out on a limb

Anyone who has seen a modern whale skeleton in a museum and noted it carefully may have noticed that though whales lack hind limbs, they do have a bit of bone back there where the hind limbs ought to be. While this is suggestive of a vestigial characteristic (a feature in a modern organism that has a reduced role relative to the role the structure played in an ancestral species), it’s hardly a smoking gun for evolution. Still, it’s consistent with the idea.

When we look at the cetacean fossil record, we also see forms suggestive of a progressive loss of hind limb function and structure over time, as David Kerk and Darrel Falk have elegantly explained before. Again, if one were resistant to evolutionary explanations, it would be possible (if a bit strained) to interpret these creatures as having been created directly as we find them in the fossil record. The facts that we do not see these forms in the present day, and that they seem to blur the distinctions between terrestrial tetrapods and whales might make one a bit uncomfortable, however.

Recent work on cetacean embryogenesis (how whales and their relatives develop from fertilized eggs into fully-formed baby whales) has shed even more light on the issue for modern species, however. Dolphin embryos actually have four limbs early in their development, as well as a few facial hairs, just as any good mammal should have. The hind limbs and hairs are lost later in development, and work on the molecular signaling events that halt hind limb growth and cause the limb bud to regress into the body wall have now been worked out in some detail. Moreover, early in dolphin development the nostrils are distinct and on the front of the face, and only fuse into a blowhole and migrate to the top of the head later in development. Early dolphin embryogenesis is distinctly mammalian and uncannily tetrapod-like.

… and passing the test

Taken in isolation, these facts about whales are interesting trivia. Taken together, however, they begin to form a picture entirely consistent with the prediction that modern whales are derived from terrestrial ancestors. The true strength of evolution as a scientific theory for the origin of whales is this: not that we can prove it, (for no theory is ever proven in science due to its permanently provisional nature), nor that we have full access to every bit of data we would like (consider how fragmentary the fossil record is, for example), but rather that we haven’t been able to disprove it yet, despite our best efforts. Descent with modification remains a productive educated guess that grows stronger with each investigation.

In the next post in this series, we’ll explore some additional lines of evidence for cetacean evolution that further illustrate the predictive power of evolutionary theory.

For further reading

Evidences for Evolution, Part 2a: The Whale's Tale

Evidences for Evolution, Part 2b: The Whale's Tale
J. G. M. Thewissen, M. J. Cohn, L. S. Stevens, S. Bajpai, J. Heyning, and W. E. Horton, Jr. (2006). Developmental basis for hind-limb loss in dolphins and origin of the cetacean bodyplan. Proceedings of the National Academy of Sciences 103 (22), 8414–8418. available freely online.