The first approach naturalists took to dealing with the great variety of animals was to sort them into groups, such as vertebrates (including fish, amphibians, reptiles, birds, and mammals) and arthropods (insects, crustaceans, arachnids, and more), but between and within these groups there are many differences. What makes a fish different from a salamander? Or an insect from a spider? On a finer scale, clearly a leopard is a cat, but what makes it different from a domestic tabby? And closer to home, what makes us different from our chimpanzee cousins?

The key to answering such questions is to realize that every animal form is the product of two processes--development from an egg and evolution from its ancestors. To understand the origins of the multitude of animal forms, we must understand these two processes and their intimate relationship to each other. Simply put, development is the process that transforms an egg into a growing embryo and eventually an adult form. The evolution of form occurs through changes in development.

Both processes are breathtaking. Consider that the development of an entire complex creature begins with a single cell--the fertilized egg. In a matter of just a day (a fly maggot), a few weeks (a mouse), or several months (ourselves), an egg grows into millions, billions, or, in the case of humans, perhaps 10 trillion cells formed into organs, tissues, and parts of the body. There are few, if any, phenomena in nature that inspire our wonder and awe as much as the transformation from egg to embryo to the complete animal. One of the great figures in all of biology, Darwin's close ally Thomas H. Huxley, remarked:

The student of Nature wonders the more and is astonished the less, the more conversant he becomes with her operations; but of all the perennial miracles she offers to his inspection, perhaps the most worthy of admiration is the development of a plant or of an animal from its embryo. -- Aphorisms and Reflections (1907)

The intimate connection between development and evolution has long been appreciated in biology. Both Darwin, in The Origin of Species (1859) and The Descent of Man (1871), and Huxley in his short masterpiece, Evidence as to Man's Place in Nature (1863), leaned heavily on the facts of embryology (as they were in the mid-nineteenth century) to connect man to the animal kingdom and for indisputable evidence of evolution. Darwin asked his reader to consider how slight changes, introduced at different points in the process and in different parts of the body, over the course of many thousands or a million generations, spanning perhaps tens of thousands to a few million years, can produce different forms that are adapted to different circumstances and that possess unique capabilities. That is evolution in a nutshell.

For Huxley, the nub of the argument was simple: we may marvel at the process of an egg becoming an adult, but we accept it as an everyday fact. It is merely then a lack of imagination to fail to grasp how changes in this process that are assimilated over long periods of time, far longer than the span of human experience, shape life's diversity. Evolution is as natural as development. [SNIP]

While Darwin and Huxley were right about development as key to evolution, for more than one hundred years after their chief works, virtually no progress was made in understanding the mysteries of development. The puzzle of how a simple egg gives rise to a complete individual stood as one of the most elusive questions in all of biology. Many thought that development was hopelessly complex and would involve entirely different explanations for different types of animals. So frustrating was the enterprise that the study of embryology, heredity, and evolution, once intertwined at the core of biological thought a century ago, fractured into separate fields as each sought to define its own principles.

Because embryology was stalled for so long, it played no part in the so-called Modern Synthesis of evolutionary thought that emerged in the 1930s and 1940s. In the decades after Darwin, biologists struggled to understand the mechanisms of evolution. At the time of The Origin of Species, the mechanism for the inheritance of traits was not known. Gregor Mendel's work was rediscovered decades later and genetics did not prosper until well into the 1900s. Different kinds of biologists were approaching evolution at dramatically different scales. Paleontology focused on the largest time scales, the fossil record, and the evolution of higher taxa. Systematists were concerned with the nature of species and the process of speciation. Geneticists generally studied variation in traits in just a few species. These disciplines were disconnected and sometimes hostile over which offered the most worthwhile insights into evolutionary biology. Harmony was gradually approached through an integration of evolutionary viewpoints at different levels. Julian Huxley's book Evolution: The Modern Synthesis (1942) signaled this union and the general acceptance of two main ideas. First, that gradual evolution can be explained by small genetic changes that produce variation which is acted upon by natural selection. Second, that evolution at higher taxonomic levels and of greater magnitude can be explained by these same gradual evolutionary processes sustained over longer periods.

The Modern Synthesis established much of the foundation for how evolutionary biology has been discussed and taught for the past sixty years. However, despite the monikers of "Modern" and "Synthesis," it was incomplete. At the time of its formulation and until recently, we could say that forms do change, and that natural selection is a force, but we could say nothing about how forms change, about the visible drama of evolution as depicted, for example, in the fossil record. The Synthesis treated embryology as a "black box" that somehow transformed genetic information into three-dimensional, functional animals.

The stalemate continued for several decades. Embryology was preoccupied with phenomena that could be studied by manipulating the eggs and embryos of a few species, and the evolutionary framework faded from embryology's view. Evolutionary biology was studying genetic variation in populations, ignorant of the relationship between genes and form. Perhaps even worse, the perception of evolutionary biology in some circles was that it had become relegated to dusty museums.

Such was the setting in the 1970s when voices for the reunion of embryology and evolutionary biology made themselves heard. Most notable was that of Stephen Jay Gould, whose book Ontogeny and Phylogeny revived discussion of the ways in which the modification of development may influence evolution. Gould had also stirred up evolutionary biology when, with Niles Eldredge, he took a fresh look at the patterns of the fossil record and forwarded the idea of punctuated equilibria--that evolution was marked by long periods of stasis (equilibria) interrupted by brief intervals of rapid change (punctuation). Gould's book and his many subsequent writings reexamined the "big picture" in evolutionary biology and underscored the major questions that remained unsolved. He planted seeds in more than a few impressionable young scientists, myself included.

To me, and others who had been weaned on the emerging successes of molecular biology in explaining how genes work, the situations in embryology and in evolutionary biology were both unsatisfying, but they presented enormous potential opportunities. Our lack of embryological knowledge seemed to turn much of the discussion in evolutionary biology about the evolution of form into futile exercises in speculation. How could we make progress on questions involving the evolution of form without a scientific understanding of how form is generated in the first place? Population genetics had succeeded in establishing the principle that evolution is due to changes in genes, but this was a principle without an example. No gene that affected the form and evolution of any animal had been characterized. New insights in evolution would require breakthroughs in embryology.

Today’s blog was an excerpt taken from the Introduction of Endless Forms Most Beautiful, (c. 2006), which was a finalist for both the Los Angeles Times Book Prize and the National Academy of Sciences Communication Award, as well as being a Discover magazine and USA Today “Top Science Books of the Year.” Learn more here.

In tomorrow’s blog, we move to the concluding chapter, where Sean Carroll summarizes some of the most exciting lessons learned from research in Evo Devo.

Editorial Policy: The editing for these excerpts involves removing the odd sentence or two—indicated by putting [SNIP] at the appropriate point(s)—and sometimes inserting annotations where warranted [also enclosed in square brackets] to provide background information.

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

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

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

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

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

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

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

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

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

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

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

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

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

Looking Ahead

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

References and Credits

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

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

Editorial Policy

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

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. 

Evidence from the Size of the Universe

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

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

Evidence from the Moon and Planets

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

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

Evidence from the Orbits of Asteroids

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

Evidence from Meteorites

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

Evidence from Star Clusters

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

Multiple Lines of Evidence

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

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

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

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

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

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

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

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

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

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

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

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

“It’s much more difficult.”

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

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

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

And what do these galaxies look like?

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

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

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

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

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

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

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

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

“I think about that extremely rarely.”

Shoot, I’d gone too far, I thought.

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

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

Good science has an addiction to theories,¹ and for science to be good science, it must deal with good scientific theories.  What constitutes a good scientific theory?  That is a very involved question, but a user’s view of good scientific theories looks something like this:

1.  A scientific theory is not a guess or suspicion.  For example, “I have a theory about who shot President Kennedy,” reflects the colloquial meaning of the word “theory,” and not the meaning conveyed by scientists when they use the word “theory.”  
2. Scientific theories are convincing explanatory frameworks that efficiently integrate a large body of evidence about the world.  Good scientific theories have the capacity to make sense of a wide range of data that made less sense before the introduction of the theory. 
3. In order to be called a scientific theory, it must have been successfully tested and re-tested many times.²
4. A scientific theory must be falsifiable in order to be truly scientific.  The theory has to live constantly at risk from new data.³ 
5. A theory must have predictive power.⁴  Good theories allow scientists to make predictions based on the theory that, when tested, turn out to be at least roughly correct. 

These are not the only characteristics of a scientific theory, but they probably represent the most important features for practitioners of science. 

If we hold contemporary evolutionary theory to these standards, how well does it do?  Since the inception of evolutionary theory by Charles Darwin in 1859 with the publication of On the Origin of Species, there are four characteristics of evolutionary theory that have endured 150 years of further research:

1. Living species are descendants of other species that lived in the past.
2. These past species lived in populations that underwent gradual transformation so that the individuals in these populations changed their appearance, behaviors, metabolisms, and life histories over long spans of time.⁵
3. New forms of life arose by means of a process called speciation in which one lineage splits into two distinct lineages.  This continual splitting of organismal lineages leads to a nested genealogy of species.  This nested genealogy forms a veritable tree of life, whose root represents the first species to arise and whose twigs represent the millions of species living today.  If you trace back any pair of twigs from the modern species you will find that their histories merge at some node on the tree where the two species share a common ancestor.⁶ 
4. This process of biological change that takes place throughout the advance of geologic time, or evolution, occurs by means of variation in organisms (which we know today is due to genetic mutations) that is acted on by either random genetic drift or natural selection. Those individuals with variations better suited to the current environment leave more offspring, thus changing the average appearance of the population over time and making it a better fit to the environment. This improving fit between organisms and their environment gives the appearance of organisms having been well designed for their milieu.⁷ 

What is the evidence for these aspects of evolutionary theory?  The evidence is actually immense, but I will restrict this discussion to just a few items. 

First there is the fossil record. If life results from a natural process such as biological evolution, then we should observe a progression of fossil organisms that proceed from relatively simple, single-celled organisms in the oldest rocks to more complex, multicellular organisms in younger rocks. When paleontologists examine the geologic column, they perceive that some of the oldest and deepest layers of the geologic column contain fossils of microorganisms, and then marine invertebrates in younger layers above those,⁸ and then much later and higher up in the geologic column fish appear, followed later and higher still by amphibians, and then by reptiles, mammals, and birds.⁹  Thus, the general presentation of the fossil record in the rock record comports exactly with what the theory of evolution predicts. 

However, the fossil story gets even better, because scientists can trace evolutionary trends throughout the fossil record.  For example, horses get bigger, fuse their leg bones and toes into a single bone with a thick hoof and grow the thickness of their tooth enamel;¹⁰ Cenozoic brachiopod shells get narrower, decrease their rib numbers and beak angle;¹¹ diatoms get bigger;¹² and primate fossils reduce the size of their teeth and expand the size of their brains.¹³ 

Additionally, Darwin predicted that there should be organisms preserved in the fossil record that possess features found in two different types of creatures. Such organisms are “transitional forms” that bridge the gap between different types of organisms.¹⁴ However, the fossil record of Darwin’s time provided little evidence of such transitional forms.¹⁵ Therefore, Darwin gambled that future paleontological research would provide sufficient evidence to corroborate his theory. How did this gamble turn out? Since Darwin’s time, paleontologists have discovered transitional fossils that are part fish and tetrapod,¹⁶ part amphibian and part reptile,¹⁷ part dinosaur and part bird,¹⁸ and part reptile and part mammal.¹⁹ Once again, we would predict such paleontological trends and the existence of such transitional fossils if life came about through a process of organic evolution. Clearly paleontological research since Darwin’s time has powerfully vindicated his theory. 

Please join us for part two of this post tomorrow, where we will discuss how signs of evolution can be detected in organisms living today, and how evidence from multifarious scientific fields—not just biology and paleontology—have bolstered the theory of evolution and added to our understanding of how natural selection works.

Notes

1. Ratzsch, Del. The Battle of Beginnings: Why Neither Side Is Winning the Creation-Evolution Debate. Downer’s Grove, WI: Intervarsity Press, 1996. pp. 104–119. 
2. Kitcher, Philip. Abusing Science: The Case Against Creationism. Cambridge, MA: MIT Press, 1983. pp. 45–54.
3. Ibid, 42–48.  .
4. Ratzsch, Del. Science and Its Limits: The Natural Sciences in Christian Perspective. Downer’s Grove, WI: Intervarsity Press, 2000. pp. 21–24. 
5. Hall, Brian K., and Benedikt Hallgrimsson. Strickberger’s Evolution. 5th ed. Burlington, MA: Jones and Bartlett, 2013. pp. 19–68. 
6. Kitcher, Philip. Living With Darwin: Evolution, Design, and the Future of Faith. New York: Oxford University Press, 2009. pp. 43–71. 
7. Futuyma, Douglas J. Evolution. 3rd ed. Sundbury, MA: Sinauer Associates, 2013. pp. 281–343. 
8. Valentine, James W. On the Origin of Phyla. Chicago: University of Chicago Press, 2006. pp. 429–464. 
9. Carroll, Robert L. Vertebrate Paleontology and Evolution. New York: W. H. Freeman and Company, 1990. 
10. MacFadden, “Horses, the Fossil Record, and Evolution,” 131–158; McFadden, Bruce J. “Fossil Horses from "Eohippus" (Hyracotherium) to Equus: Scaling, Cope's Law, and the Evolution of Body Size.” Paleobiology 12, no. 4 (1986): 355–69.; Prothero, Donald R., and R.M. Schoch, eds. The Evolution of Perissodactyls. New York: Clarendon Press, 1989. ; McFadden, Bruce J. Fossil Horses. Systematics, Paleobiology, and Evolution of the Family Equidae. Cambridge, Cambridge University Press, 1993. 
11. McNamara, Kenneth J. “Evolutionary Trends.” In Encyclopedia of Life Sciences (New York: Macmillan Publishers Ltd, 2001), pp. 1–7. 
12. Litchman, E., C. A. Klausmeier, and K. Yoshiyama. “Contrasting Size Evolution in Marine and Freshwater Diatoms.” Proceedings of the National Academy of Sciences USA 106, no. 8 (2009): 2665–2670.
13. Tattersall, Ian. The Fossil Trail: How We Know What We Think We Know About Human Evolution. New York: Oxford University Press, 2008. pp. 89–198. 
14. Darwin, Charles. On the Origin of Species by Means of Natural Selection or the Preservation of Favoured Races in the Struggle for Life. London: Penguin Books, 1985. p. 292.
15. Hunt, Gene. “Evolution in Fossil Lineages: Paleontology and The Origin of Species.” Supplement American Naturalist 176 (2010): S61–S76. 
16. Clack, Jennifer A. Gaining Ground: The Origin and Evolution of Tetrapods. Bloomington, IN: Indiana University Press, 2002; Daeschler, Edward B., Neil H. Shubin, and Farish A. Jenkins, Jr. “A Devonian Tetrapod-Like Fish and the Evolution of the Tetrapod Body Plan,” Nature 440, no. 7085 (2006): 757–63; Shubin, Neil H., Edward B. Daeschler, and Farish A. Jenkins, Jr. “The Pectoral Fin of Tiktaalik roasae and the Origin of the Tetrapod Limb.” Nature 440, no. 7085 (2006).): 764–71; Downs, Jason P., Edward B. Daeschler, Farish A. Jenkins, and Neil H. Shubin. "The Cranial Endoskeleton of Tiktaalik roseae." Nature 455, no. 7215 (2008): 925–9. 
17. Carroll, Robert L. Vertebrate Paleontology and Evolution. New York: W. H. Freeman and Company, 1990. pp. 156–216. 
18. Shipman, Pat. Taking Wing: Archaeopteryx and the Evolution of Bird Flight. New York: Touchstone, 1998. pp. 169–244.  
19. Prothero, Donald R. Evolution: What the Fossils Say and Why It Matters. New York: Columbia University Press, 2007. pp. 271–297. 

A common argument leveled against the theory of evolution is that scientists have not been able to produce the expected transitional fossils that show the change of one species into another. If evolution were true, wouldn’t there be instances of clear intermediary species, like, for example, a species that was half whale and half hippo to show the transition between those two? In this BioLogos podcast, Kelsey Luoma addresses this misconception about what a transitional fossil actually is. Rather than a mix between two related species, transitional fossils point back to the common ancestors that modern species share. The fact is that the number of transitional species is massive and it grows with each passing year. Given the rarity with which organisms are actually fossilized, the amazing thing is actually the completeness of the fossil record, not its incompleteness. The transitional species story strongly supports, and certainly does not disprove, evolutionary theory. ¹

1. To hear the full audio clips which have been referenced go to:

• Rational Response Debate with Kirk Cameron (from Way of the Masters)
• Behind the Scenes with Dr. Neil Shubin (from Cincinnati Museum Center)
• Mark Norell Publishes New Archaeopteryx Findings (from American Museum of Natural Sciences)
• Texas A&M Professor Discusses Findings of Autralopithecus Sediba and its Relationship to Humans (from Texas A&M University)
• Intro/outro music composed by Martin Minor (Minor2Go).

An audio only version of the podcast can be downloaded here.

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

In 1774, the French chemist Antoine Lavoisier replicated the relevant experiments in more controlled ways to demonstrate that mass was conserved during combustion. He also renamed the part of the air that burned 'oxygène.' English scientists resisted the French scientist's new name, not least because the English Priestly had already published his discovery of the gas. 'Oxygen' nonetheless entered the common English vocabulary in part due to one of the first popular science books, The Botanic Garden (1791), which included a poem praising the gas using the preferred French name. By coincidence, this book also promoted some early ideas about biological evolution (specifically, it suggested that sexual reproduction might be important to evolution, which might help to explain the popularity of a book of poems about science). It was written by Erasmus Darwin, the grandfather of Charles Darwin, who first proposed the modern form of the theory of biological evolution in his 1859 book, On the Origin of Species.

150 years later, we are discovering that the lines connecting evolution and oxygen run deeper than the Darwin family tree. We now know, for instance, that for roughly half of the Earth's 4.6-billion-years of history, there was little to no oxygen in the atmosphere. Instead, oxygen entered the atmosphere in two major pulses, with one between 2.4 and 2.2 billion years ago, and another between 0.8 and 0.54 billion years ago. Recent evidence suggests that the first pulse may have actually been the largest event in a series of fits and starts beginning at around 2.7 billion years ago that finally produced a stable low oxygen atmosphere by around 1.8 billion years ago.

Remarkably, both episodes of atmospheric oxygenation happened just before explosions in biological diversity. We have spotty evidence of unicellular eukaryotes (cells with nuclei) before 2.4 billion years ago, but the first fossil evidence for large, diverse eukaryotic communities comes at 1.5 billion years ago. If you are a human, this is part of your history; humans are multicellular eukaryotes descended from one of these early unicellular pioneers. Multicellular animal life is an innovation that seems to have required more oxygen: animals don't appear in the fossil record until about 0.61 billion years ago, toward the end of the second pulse of oxygen.

It is, perhaps, not surprising that major evolutionary events in the eukaryotic family tree, including the origin and diversification of the animals, would be tied to or even driven by major changes in atmospheric oxygen abundance. Eukaryotes generally, and animals specifically, are oxygen lovers. As the subjects of Mayow and Priestly died to prove, we require oxygen for respiration. In general, the larger and more organizationally complex we are (for instance, a human versus a slime mold), the more oxygen we require.

But where did all the oxygen come from? Ultimately, it was produced by the bacterial equivalents of the plants in Joseph Priestley's experiment, a group of photosynthetic microbes called the cyanobacteria. These bacteria are the first and only organisms to have evolved the ability to produce oxygen by photosynthesis. In fact, plants are able to photosynthesize only because their cells harbor descendants of one of the early cyanobacteria. We call them chloroplasts and think of them as little cellular organs, but they are actually the great-great-great... granddaughters of a cyanobacterium that long ago gave up its independence in exchange for the stable environment inside a eukaryotic cell. In any case, photosynthesis is the only known geological process capable of producing oxygen at the rates required for the two pulses of atmospheric oxygenation. The first pulse was probably largely accomplished by cyanobacteria, while the second pulse was probably mostly associated with the cyanobacterial denizens of eukaryotic algae.

What is remarkable about all of this is the extent to which modern life and the atmosphere are products of each other's evolution. The tiniest of photosynthetic organisms played one of the most important roles in shaping the sky, and the sky helped to usher in the age of animals! As a Christian and a geobiologist, I do not believe that this relationship is anticipated or predicted by the Biblical creation accounts.

But then again, why should it have been? The original audience for these accounts would have found concepts like bacteria or even oxygen incomprehensible. The people for whom the Bible was originally addressed thought about origins primarily in terms of ongoing national conflicts and the current human condition. Faced with a variety of violent creation myths that reinforced national conflicts, Genesis said that the universe was created to be good, peaceful, and orderly by one god. It specifically listed things worshipped by other nations as creatures of that god, and in the climax of the creation account, Abraham was called by the same god to be a blessing to all the nations through Israel.

I am not claiming that the Bible cannot be read in a way that can shape us in real and meaningful ways today. In fact, for those who believe that the Bible is inspired, part of the meaning of inspiration has to be that the Bible is God's powerful word to both those with no concept of modern science (most of the world's population, both today and in the past) and to those deeply engaged in its practice. But, and this is a big but, we contemporary Americans read the Bible best when we are sensitive to the assumptions of the original audience, carefully observe how the Bible transformed those assumptions, and look for opportunities to do the same thing with our thinking.

I think that it is important for Christians to reflect on the view of origins that science has given us in light of the thinking evident in the Biblical creation accounts. We have to do this because science gives us a story that is inherently without philosophical or theological meaning; it is up to us to give it meaning by understanding it in relationship with our beliefs. For instance, some see the evolutionary history of life and the Earth and give that history meaning by elevating chance and necessity to the level of prime actors in their own modern creation account. This meaning is not inherent to the theory of evolution; it is supplied by an atheistic belief system external to the theory. I suggest that this view mistakes created things (chance and necessity) for the Creator.

Others have preferred to see the regularity of the universe as the action of an orderly God. This is an old approach to natural theology that was popular among many early scientists, and saw God as responsible for doing such things as maintaining the planets in consistent paths around the sun. Still others look for God in the unexplained. This is a newer approach that sees God as acting primarily in short bursts not explainable by the regular, orderly function of the universe. Looking for God in these ways is a little like trying to capture him in a bell jar, an approach that worked perfectly well with oxygen for Mayow, Priestley, and Lavoisier, but one that is unlikely to impress the Creator described in the Bible.

I prefer to see the same history in the light of a God who desires to share aspects of his nature with his creation, notably including his creativity. Just as he has made humans to be creators (with a little 'c'), he has given the rest of our world the gift of being instrumental in its own creation through the process of evolution. This surely must have been part of what God saw when he described his creation as good! It is my hope that the modern American church can learn to see the goodness of creation in things like the evolutionary history of life and the atmosphere, as well.

This post first appeared in October 2009

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

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

The Milky Way

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

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

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

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

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

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

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

The Sun

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

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

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

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

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

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

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

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

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

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

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

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

Notes

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

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

Sporadic extinction

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

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

Extinction, en masse

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

Speciation, en masse

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

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

Clearing the deck, and re-filling the niches

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

For further reading:

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

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

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

(Click image for full resolution)

In a Nutshell

In Detail

Introduction

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

Age of the Earth from seasonal rings and layers

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

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

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

Age of the Earth and solar system from radiometric dating

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

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

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

PLEASE READ THE REST OF THE ANSWER HERE.

Notes

1. Davis A. Young, ”How Old Is It? How Do We Know? A Review of Dating Methods – Part One: Relative Dating, Absolute Dating, and Non-radiometric Dating” Perspectives on Science and Christian Faith, Vol 58 No 4 (2006), p. 264. (PDF)
2. Roger C. Weins, "Radiometric Dating: A Christian Perspective", The American Scientific Affiliation (2002). See also North Greenland Ice Core Project Members, “High-resolution Record of Northern Hemisphere Climate Extending into the Last Interglacial Period,” Nature 431 (2004): 147–151, which reports ages back to 123,000 years. (web article)
3. EPICA Community Members, “Eight Glacial Cycles from an Antarctic Ice Core,” Nature 429 (2004): 623–628.
4. Young earth creationists reject radiometric dating methods, including claims that decay rates are not constant. For a critical review, see Randall Isaac “Assessing the RATE Project”, Perspectives on Science and Christian Faith, vol 59, no 2, June 2007, p.143-146. (PDF)
5. See Wiens and references therein. (web article)
6. Wilde et al. “Evidence from detrital zircons for the existence of continental crust and oceans on the earth 4.4 Gyr ago,” Nature (2001) 409, 175-178.
7. See Davis A Young, ”How Old Is It? How Do We Know? A Review of Dating Methods—Part Two: Radiometric Dating: Mineral, Isochron and Concordia Methods” Perspectives on Science and Christian Faith, Vol 59, No 1 (2007) and references therein (PDF)
]]> Sat, 14 Jul 12 05:02:55 -0700 http://biologos.org/questions/what-evidence-do-we-have-for-evolution-besides-fossils-and-genes?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication http://biologos.org/questions/what-evidence-do-we-have-for-evolution-besides-fossils-and-genes?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication Scientists have found multiple lines of evidence for evolution, not just one or two. These types of evidence are independent of each other, coming from sources as different as ancient fossils and modern genetics labs. Evidence also comes from comparing the anatomy of creatures living today. All creatures with four limbs (whether mammals, birds, or reptiles) have the same bone structure in each limb, pointing to their descent from a common ancestor. More evidence comes from biogeography. Isolated islands are missing common species found on the mainland, but are filled with many unique species that can be related by a common ancestor. Finally, evidence comes from embryonic development. As an embryo of a mammal grows, its heart develops through stages similar to fish, amphibians, and reptiles. God’s creation declares the history of life in many different ways. All these ways are pointing to a consistent picture of God creating through evolution. Coming soon.]]> Fri, 13 Jul 12 13:25:46 -0700 http://biologos.org/blog/the-fossil-record?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication http://biologos.org/blog/the-fossil-record?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication There are two opposite errors which need to be countered about the fossil record: 1) that it is so incomplete as to be of no value in interpreting patterns and trends in the history of life, and 2) that it is so good that we should expect a relatively complete record of the details of evolutionary transitions within all or most lineages. The Fossil Record: Is there enough evidence ?

There are two opposite errors which need to be countered about the fossil record: 1) that it is so incomplete as to be of no value in interpreting patterns and trends in the history of life, and 2) that it is so good that we should expect a relatively complete record of the details of evolutionary transitions within all or most lineages.

What then is the quality of the fossil record? It can be confidently stated that only a very small fraction of the species that once lived on Earth have been preserved in the rock record and subsequently discovered and described by science.

A more expanded discussion of this topic can be found in Miller, K.B., 2003, “Common descent, transitional forms, and the fossil record,” IN, K.B. Miller (ed.), Perspectives on an Evolving Crreation, Wm. B. Eerdmans, Grand Rapids.

There is an entire field of scientific research referred to as "taphonomy" -- literally, "the study of death." Taphonomic research includes investigating those processes active from the time of death of an organism until its final burial by sediment. These processes include decomposition, scavenging, mechanical destruction, transportation, and chemical dissolution and alteration. The ways in which the remains of organisms are subsequently mechanically and chemically altered after burial are also examined -- including the various processes of fossilization. Burial and "fossilization" of an organism's remains in no way guarantees its ultimate preservation as a fossil. Processes such as dissolution and recrystallization can remove all record of fossils from the rock. What we collect as fossils are thus the "lucky" organisms that have avoided the wide spectrum of destructive pre- and post-depositional processes arrayed against them.

Soft-bodied organisms, and organisms with non-mineralized skeletons have very little chance of preservation under most environmental conditions. Until the Cambrian nearly all organisms were soft-bodied, and even today the majority of species in marine communities are soft-bodied. The discovery of new soft-bodied fossil localities is always met with great enthusiasm. These localities typically turn up new species with unusual morphologies, and new higher taxa can be erected on the basis of a few specimens! Such localities are also erratically and widely spaced geographically and in geologic time.

Even those organisms with preservable hard parts are unlikely to be preserved under "normal" conditions. Studies of the fate of clam shells in shallow coastal waters reveal that shells are rapidly destroyed by scavenging, boring, chemical dissolution and breakage. Occasional burial during major storm events is one process that favors the incorporation of shells into the sedimentary record, and their ultimate preservation as fossils. Getting terrestrial vertebrate material into the fossil record is even more difficult. The terrestrial environment is a very destructive one: with decomposition and scavenging together with physical and chemical destruction by weathering.

The potential for fossil preservation varies dramatically from environment to environment. Preservation is enhanced under conditions that limit destructive physical and biological processes. Thus marine and fresh water environments with low oxygen levels, high salinities, or relatively high rates of sediment deposition favor preservation. Similarly, in some environments biochemical conditions can favor the early mineralization of skeletons and even soft tissues by a variety of compounds (eg. carbonate, silica, pyrite, and phosphate). The likelihood of preservation is thus highly variable. As a result, the fossil record is biased toward sampling the biota of certain types of environments, and against sampling the biota of others.

In addition to these preservational biases, the erosion, deformation and metamorphism of originally fossiliferous sedimentary rock have eliminated significant portions of the fossil record over geologic time. Furthermore, much of the fossil-bearing sedimentary record is hidden in the subsurface, or located in poorly accessible or little studied geographic areas. For these reasons, of those once-living species actually preserved in the fossil record, only a small portion have been discovered and described by science. However, there is also the promise of continued new and important discovery.

The forces arrayed against fossil preservation also guarantee that the earliest fossils known for a given animal group will always date to some time after that group first evolved. The fossil record always provides only minimum ages for the first appearance of organisms.

Because of the biases of the fossil record, the most abundant and geographically widespread species of hardpart-bearing organisms would tend to be best represented. Also, short-lived species that belonged to rapidly evolving lines of descent are less likely to be preserved than long-lived stable species. Because evolutionary change is probably most rapid within small isolated populations, a detailed species-by-species record of such evolutionary transitions is unlikely to be preserved. Furthermore, capturing such evolutionary events in the fossil record requires the fortuitous sampling of the particular geographic locality where the changes occurred.

Using the model of a branching tree of life, the expectation is for the preservation of isolated branches on an originally very bushy evolutionary tree. A few of these branches (lines of descent) would be fairly complete, while most are reconstructed with only very fragmentary evidence. As a result, the large-scale patterns of evolutionary history can generally be better discerned than the population-by-population or species-by-species transitions. Evolutionary trends over longer periods of time and across greater anatomical transitions can be followed by reconstructing the sequences in which anatomical features were acquired within an evolving branch of the tree of life.

]]> Fri, 13 Jul 12 05:00:15 -0700 Keith Miller http://biologos.org/blog/what-is-the-higgs-boson?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication http://biologos.org/blog/what-is-the-higgs-boson?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication At a press conference on July 4, 2012, and with 99.99994% confidence (5 sigma), CERN announced the discovery of a particle consistent with that of a Higgs boson (a.k.a. “the God particle”). This is very exciting for elementary particle physicists. But what is the Higgs particle, and what is its meaning? At a press conference on July 4, 2012, and with 99.99994% confidence (5 sigma), CERN announced the discovery of a particle consistent with that of a Higgs boson (a.k.a. “the God particle”). This is very exciting for elementary particle physicists. It is also getting the attention of press and general public. But what is the Higgs particle, and what is its meaning?

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

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

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



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



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

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

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

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



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

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

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

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





Updated July 12, 2012.

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

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

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



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

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

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

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

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



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

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

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

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

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



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

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

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

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

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

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




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


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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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


]]> Sat, 05 May 12 05:30:09 -0700 Karl Giberson