These were just a few of the questions that motivated us at BioLogos to commission a survey of pastors on origins.  In 2012, the Barna Group conducted 743 telephone interviews with pastors from across the US, from churches big and small, and from all Christian denominations.  This comprehensive, in-depth survey provides a fascinating analysis of views held by clergy today.   In the coming month, we’ll be digging deeper into the survey results, but for now, here are some key highlights:

#1: Pastors hold a diversity of views on origins.

Overall, while a slight majority of the pastors surveyed fall under the label of Young Earth Creationism (54%), sizeable portions of clergy accept Progressive Creation (15%) and Theistic Evolution (18%).

The numbers varied widely based on a number of factors, however. Pastors of mainline churches were most likely to accept Theistic Evolution, while non-Mainline, Charismatic, and Southern Baptist pastors were overwhelmingly Young Earth Creationists. Pastors of larger churches were also more likely to accept Theistic Evolution.

Regionally, the highest percentage of YEC pastors was found in South, while the highest percentage of pastors accepting TE was in the Midwest. Pastors from the western states were the least likely to accept TE.

#2: Most pastors think science and faith questions are important.

Regardless of their views, the majority of pastors surveyed feel that the Church needs to look at how it handles issues of science. 72% of pastors with YEC views and 73% of pastors with TE views agree with the statement that “the Christian community needs to take a serious look at its understanding of science and human origins in order to maintain its witness in the world.” (The numbers are slightly lower for pastors who hold to Progressive Creation and who are uncertain).

Similarly, 66% of YEC pastors and 61% of both TE and Progressive Creation pastors agree that “younger adults today are more concerned than ever about whether faith and science are compatible.”

#3: Clergy think disagreements on science and faith harm our witness (but for different reasons).

Clergy across all three viewpoints feel that disagreements are harming the Church’s outreach, but they differ in how they view that harm.

YEC pastors overwhelming agreed (85%) that “Christian disagreement on matters of creation and evolution is compromising our witness to the world.” However, a majority of TE pastors disagreed with the statement (63%).

Conversely, a majority of TE pastors (63%) agreed that “The church’s posture toward science prevents many non-Christians from accepting Christianity,” while a majority of YEC and Progressive Creation leaning pastors disagreed (59%).

#4: Pastors aren’t avoiding science.

The majority of pastors think that addressing issues of science for their congregations is an important part of their work. Of those surveyed, 72% felt that addressing science issues in the local community was somewhat (51%) or very (21%) urgent. When asked about science on a national and global level, even more pastors felt that addressing science issues is important (43% somewhat and 46% very). Furthermore, 79% of pastors included scientific themes in at least one sermon in the past year, and 40% had included them in at least ten sermons.

The majority of clergy across all four viewpoints also agreed with the statement “Just as scripture should influence human interpretation of science, science should also inform our understanding of scripture.” The numbers were highest for TE pastors and those who are uncertain (81% and 72%, respectively), though over half of YEC and PC pastors also agreed (52% and 65%, respectively).

Finally, although YEC’s are more reluctant than other pastors to say “science should inform understanding of scripture, they strongly agree (84%) that “The Christian community needs a greater commitment to showing how young earth creationism is consistent with science.”

#5: However, they are concerned about evolution for biblical reasons.

Over half of pastors said they had “major concerns” about the idea that God used evolution. The main reasons for that concern were that the idea “undermines the authority of Scripture” (64%), “views portions of the Bible as non-literal, like Genesis” (62%), “raises doubts about a historical Adam and Eve” (61%), and “raises questions about how and when death and sin entered the world” (59%). However, 26% of pastors saw no concern with the idea that God used evolution.

#6: The majority of clergy accept parts of scripture as symbolic.

60% of the pastors surveyed felt that “some portions of the Bible are symbolic, but all that it teaches is authoritative.” Clergy whose views fall under theistic evolution and progressive creation were more likely to accept this statement (79% and 73% respectively), but a sizeable number of YEC pastors (40% among the core followers and 49% among those leaning towards YEC) also agreed with the statement.

#7: Clergy are concerned that changing their views on origins might compromise their ministry.

Over half of pastors (58%) who fell under the YEC category agreed that “If you publicly admitted your own doubts about human origins, you feel you would have a lot to lose in your ministry.” 41% of pastors in the Progressive Creation group also agreed with the statement. Pastors who were uncertain or who fell under the Theistic Evolution group were less concerned, with only 26% and 17% respectively agreeing with the statement.

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

What you can expect

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

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

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

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

How you can help

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

Getting started

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

Antibody fine-tuning

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

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

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

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

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

Antibody production and evolution both involve mutation and selection

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

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

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

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

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

Though often neutral or destructive, mutations sometimes create new functionality

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

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

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

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

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

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

In this video Conversation, Denis Alexander addresses two prominent barriers for Christians to accept evolutionary creation. The first is Biblical interpretation. When contemporary Christians interpret the early chapters of Genesis literally, they do so out of a desire to take the text seriously. Yet the early church fathers saw these chapters as figurative—and that figurative interpretation did not lesson the important foundational truths taught in these passages. The contemporary literal reading is actually a modern approach to the text in that our scientific mindset inappropriately shapes the interpretation. Since science did not even exist at the time that Genesis was written, an overly literal interpretation can actually cause us to miss the inspired message that the Biblical authors were communicating.

The second barrier is the rhetoric of the New Atheists, who claim that it is impossible to accept evolution while still believing in God. Christians should challenge this. Traditional Christian views are not in conflict with modern science. Instead, they see nature as God's work, with St. Augustine writing that "nature is what God does." As humanity develops a scientific understanding of nature, we will only learn more about the handiwork of God. 

Grantees will benefit from in-person interaction through a series of summer workshops in 2013, 2014, and 2015. These meetings will not only foster a broader knowledge base, but will build a sustained network of scholars and church leaders, both young and seasoned, who are serious about addressing the concerns of the church about evolution. Also in 2015, in connection with the third summer workshop, BioLogos will host a large conference open to scientists, scholars, and church leaders from around the world.

ECF History

In January 2012, BioLogos was awarded a multi-million dollar grant from the John Templeton Foundation to fund the work of scholars and church leaders on evolution and Christian faith. In spring 2012 we worked hard to get the word out. You may have seen announcements on the BioLogos website, in our newsletters, on the Books & Culture, Leadership Journal, or First Things websites, on your professional society’s listserv, or perhaps on your friend’s blog.

The response was overwhelming: we received 225 letters of intent for a total request of $21 million—about seven times the amount we had to offer. We needed to invite the most promising applicants to submit a full proposal, but recognizing the projects with highest potential would require broad expertise. From the beginning, we envisioned that a panel of scientists, pastors, and scholars would oversee the application and review process as well as play key advisory roles throughout the project. A team of eight highly qualified individuals came on board in the early months of the project. They reviewed each proposal and together recommended that BioLogos invite 86 applicants to submit full applications.

The deadline for submissions was October 1, 2012. As in the previous round, the ECF panel evaluated each proposal. In addition, we asked 55 other experts to participate, so that each proposal received 3-4 scores. Criteria for the decision included significance of topic, project design, creativity and innovation, long-term impact potential, feasibility, and budget.

The panel then met together November 29-30, 2012, to make the final funding decisions. In the end, they recommended that BioLogos give 37 awards, ranging from $23,000 to $300,000. BioLogos staff notified applicants of their awards on December 14, 2013.

The Grantees

As part of our objective to create a network of scholars and leaders, we awarded grants to organizations across the U.S. and the world. Thirty of the 37 grantees are domestic; seven are international, hailing from Canada, France, Great Britain, Netherlands, and Spain.

Two-thirds of the accepted projects will be led by teams—some with three or more Project Leaders. We expect that the teamwork and time spent together at our summer workshops will be the start of a long-lasting network of people dedicated to helping the church think carefully about origins.

Applicants chose to apply under one of three program tracks: interdisciplinary scholarship (Track 1), intra-disciplinary scholarship (Track 2), and translational projects (Track 3). Track 1 projects focus on both the collaboration between individuals in different disciplines and the development of projects at the interface of different content areas. Track 2 projects focus on work done within a specific discipline. Track 3 focuses on projects that encourage Christians, especially those within more conservative traditions, to engage in meaningful and productive dialogue to reduce tensions between mainstream science and the Christian faith. The numbers of grantees in Tracks 1, 2, and 3 are 6, 8, and 23, respectively.

Many of the scholarly projects tackle questions about Adam and Eve, the Fall, human identity, and Original Sin—some of the most critical interpretive issues for evangelical theology.  Some examples: 

• Theologian Oliver Crisp of Fuller Seminary will take an analytic theology approach to ask to what extent a theological account of the origin of human sin depends upon the evolution of modern humans from one and only one ancestral pair—especially if that pair does not appear to correspond to what we would think of as modern human beings. 

• Pastor Michael Gulker and philosopher James Smith, leading a large team from The Colossian Forum, ask a related question: if humanity emerged from non-human primates—as genetic, biological, and archaeological evidence seems to suggest—then what are the implications for Christian theology’s traditional account of origins, including both the origin of humanity and the origin of sin? 

• Biologist Dennis Venema of Trinity Western University and New Testament scholar Scot McKnight of Northern Seminary will write a book on the evidence for evolution and population genetics, with informed theological reflection on how these issues interact with orthodox Christianity.

• Biologist David Wilcox of Eastern University will develop an updated model of human identity which reflects the complex recent scientific advances in genetics and paleoanthropology and yet is sensitive to theological concerns.  

These are just a few of the scholarly awards; check out the Grantees page for full descriptions of all Track 1 and Track 2 projects.

All projects have translational potential, but Track 3 projects are designed to meet the needs of a particular constituency within the evangelical church. These projects run the gamut from ethics to education to media production to ministry resources.  Some examples include:

• Theologian Lee Camp of Lipscomb University will produce “The Questions in Monkey Town,” an episode of Tokens, a live variety show that features musical performances, comedic sketches, brief interpretive monologues, and dialog with authors and scholars. The episode will be performed and filmed on the site of the famous Scopes Trial in Dayton, Tennessee.

• Chaplain Joshua Hayashi and Educator Diane Sweeney of the Punahou School in Hawaii will lead a team to produce multimedia curricula aimed at helping high school students connect with their biology curricula and, at the same time, deepen their Christian faith.

• Physics teacher and pastor Benoît Hébert of Science et Foi Chrétienne in France will lead an international, multi-denominational team of French speaking Evangelical scientists, pastors and church leaders to produce a large number of resources on evolutionary creation.

• Pastor Seung-Hwan Kim of Grace Truth Community Church, a Southern Baptist church in Cambridge, Massachusetts, will produce teaching and preaching materials about evolution for church leaders.

• President Gregory Wolfe and Director of Resource Development for IMAGE will gather artists and writers of faith whose work explores the dialogue between evolutionary science and faith practice, convening a conversation between them and scientists, theologians, and church leaders in private and public conferences.

Again, this is just a taste of the diversity of Track 3 projects. Read more about each project on the Grantees page. You can look forward to an incredible variety of resources coming out of the ECF program, many of which will be featured right here on the BioLogos Forum.

For many American evangelicals it will come as a surprise to realize just how little Lewis thought was at stake in the scientific question of our biological origins. As we have seen, Lewis had no objection to the notion that “man is physically descended from animals.” Four years after admitting to being shaken by some of the writings from Bernard Acworth’s Evolution Protest Movement, Lewis could still write in a private letter, “I don’t mind whether God made man out of earth or whether ‘earth’ merely means ‘previous millennia of ancestral organisms.’ If the fossils make it probable that man’s physical ancestor’s ‘evolved,’ no matter.”¹ So far as we can tell, Lewis never took the view that belief in mere Evolution, “Evolution in the strict sense,”² “the Evolution of real biologists,” which he took to be “a genuine scientific hypothesis” and “a purely biological theorem”³ was necessarily at odds with a belief in mere Christianity.

Indeed, the final chapter of his classic book Mere Christianity, “The New Men,” assumes an evolutionary picture of life’s origins and development throughout.⁴ He writes,

Perhaps a modern man can understand the Christian idea best if he takes it in connection with Evolution. Everyone knows about Evolution…: everyone has been told that man has evolved from lower types of life.⁵

While Lewis acknowledges that “some educated people disbelieve [the theory of Evolution],” he gives no hint throughout the rest of the chapter that he is one of their number.⁶ In fact, throughout the rest of the chapter he seems to simply assume a broadly evolutionary picture of natural history (as he does in The Problem of Pain and elsewhere). So, for instance, he writes:

Thousands of centuries ago huge, very heavily armoured creatures were evolved.⁷

At the earlier stages living organisms have had either no choice or very little choice about taking the new step [of development]. Progress was, in the main, something that happened to them, not something that they did.

Century by century God has guided nature up to the point of producing creatures (humans) which can (if they will) be taken right out of nature, turned into “gods.”⁹

And he says much more in that vein. While it may be possible to read Lewis as invoking Evolution for purely illustrative purposes without actually believing in it, such a reading seems less than likely given his statements in this chapter and elsewhere. In fact, Lewis offers no hint anywhere in his public writings that he regards evolutionary theory as either untrue or conflicting with mere Christianity.

What Lewis did believe to conflict with Christian faith was what he called the great “Myth” of “Evolutionism” or “Developmentalism.” But this is not the same as evolutionary theory per se. “[We] must sharply distinguish between Evolution as a biological theorem and popular Evolutionism or Developmentalism which is certainly a Myth,” he writes in his essay “The Funeral of a Great Myth.”¹¹ Lewis believed that the great myth of “Evolutionism” conflicted not only with the Christian faith, but with Reason itself, undercutting the grounds for believing in human rationality and, therefore, in any human rationale that could be offered for believing in Evolutionism in the first place. According to Lewis,Evolutionism’s chief premise, namely, Naturalism, invalidates human reasoning itself, amounting to “an argument which proved that no argument was sound—a proof that there are no such things as proofs—which is nonsense.”¹² “All possible knowledge…depends on reasoning,” he writes in chapter III of Miracles.¹³ “We infer Evolution from fossils: we infer the existence of our own brains from what we find inside the skulls of other creatures like ourselves in the dissecting room.” All sciences, including evolutionary science, depend upon the validity of human inference for their own validity. “Unless human reasoning is valid no science can be true.”¹⁴ Naturalism, however, with its grand Myth of Evolutionism explains all of reality, including human reason, in terms of non-rational natural causes and effects, reducing all human reasoning to being no more than the accidental byproducts of chance, matter and time, and thereby undercutting the validity of reasoning itself.

However, if one allows, as Lewis apparently did, that God guided the evolution of humanity so as to make us reasonable creatures, then humanity’s descent from the animals in no way undermines the validity of human reasoning. By maintaining the distinction between Evolution as a scientific theory and Evolutionism as a popular Myth it becomes possible for one to be a full-blooded theistic evolutionist with both a robust belief in God and a robust belief in evolution. The distinction frees Christians to accept evolutionary science without knuckling under to reductionistic Scientism. Thus, in the very essay where Lewis most acerbically attacks Evolutionism, “The Funeral of a Great Myth,” Lewis also clearly allows for a form of theistic evolution. Lewis writes:

I am not in the least denying that organisms on this planet may have ‘evolved.’ But if we are to be guided by the analogy of Nature as we know her, it would be reasonable to suppose that this evolutionary process was the second half of a long pattern—that the crude beginnings of life on this planet have themselves been ‘dropped’ there by a full and perfect life.¹⁵

As Lewis makes clear in another piece, “Two Lectures,” the “full and perfect life” by which “this evolutionary process” was “dropped” exists outside of Nature, which is to say, exists outside of the purview of the natural sciences. “Is it not…reasonable to look outside Nature for the real Originator of the natural order?” he asks.¹⁶

Lewis, however, was no Deist. He clearly did not believe that the “crude beginnings of life” were simply “dropped” by God so that the “evolutionary process” would do what it would. Lewis seems to have thought that God at least superintended the evolution of humankind, particularly humanity’s cognitive capacities, in a rather hands-on manner:

For long centuries God perfected the animal form which was to become the vehicle of humanity and the image of Himself. He gave it hands whose thumb could be applied to each of the fingers, and jaws and teeth and throat capable of articulation, and a brain sufficiently complex to execute all the material motions whereby rational thought is incarnated. The creature may have existed for ages in this state before it became man: it may even have been clever enough to make things which a modern archaeologist would accept as proof of its humanity. But it was only an animal because all its physical and psychical processes were directed to purely material and natural ends. Then, in the fullness of time, God caused to descend upon this organism, both on its psychology and physiology, a new kind of consciousness which could say “I” and “me,” which could look upon itself as an object, which knew God, which could make judgments of truth, beauty, and goodness, and which was so far above time that it could perceive time flowing past.¹⁷

Whether this picture of hands-on divine guidance is friendlier towards present day Intelligent Design theory or towards theistic evolution, a la BioLogos, will be a matter for debate. Lewis does not draw the distinctions that are customary in contemporary debates surrounding evolution—macro- versus micro-evolution, Evolution qua mere common descent versus Evolution qua wholly unguided, random process, and so on—making it difficult to say with certainty what he would say if he were here today. It seems likely, however, that Lewis would not have expected the natural sciences to be able to detect God’s supernatural guidance of man’s evolutionary path any more than he expected the modern archaeologist to be able detect the moment when our ancestors crossed the threshold from beast to man, and that likelihood might count as a strike against the ID movement’s claim on Lewis. In any case, Lewis plainly outlines a view that is quite compatible with the standard evolutionary picture of common descent and that hardly amounts to Scientistic reductionism. In short, Lewis made it quite clear in his writings that he believed that there is no real conflict between mere evolution and mere Christianity.

Surprised by Jack

Whatever Lewis may have believed in private, as a spokesperson for the faith, Lewis consistently allowed that mere Christianity was compatible with mere evolutionary science, and he even took the trouble to articulate his understanding of the Fall in such a way as to harmonize it with his belief in human evolution. While some recent writers have attempted to wield Lewis as weapon in intra-Evangelical debates around Evolution, to wield a thinker is, as Martin Buber says, to treat that thinker as an ‘It’ rather than as a ‘Thou,’ to treat him as an object to be used rather than as person with the right and capacity to defy our expectations.¹⁸ We evangelicals have become so accustomed to inserting quotable quotes from Lewis’s corpus into our sermons, books, power-point presentations, Facebook walls, and Twitter feeds that we drowsily pass over the surprising elements of his thought—the elements not easily reconciled with our clean-cut theological shibboleths—without even noticing. This is an intellectual habit ripe to be broken, and it is high time we allowed the real Jack to shatter the cultural icon—indeed, the mirror—we have made out of him. At this watershed moment in the history of the Church, when so much seems to threaten to upend the faith once delivered—whether scientific or archaeological discoveries, cultural trends, or newfangled philosophies—there is doubtless much that the greatest modern exponent of mere Christianity can teach us to help us navigate these troubled times. But it is only by opening ourselves to being surprised by Jack that we will be capable of actually learning something from him.

Notes

1. C.S. Lewis to Joseph Cranfield, Feb. 28, 1955, unpublished letter, Wade Center Collection, Wheaton College, as cited in West, “Darwin in the Dock,” 113
2. Lewis, “Is Theology Poetry?,” in The Weight of Glory, 137
3. Lewis, “The Funeral of a Great Myth,” 85, 86
4. Lewis, Mere Christianity, 185-91
5. Ibid, 185
6. Ibid
7. Ibid, 186
8. Ibid, 187
9. Ibid, 188, my italics
10. Ibid
11. Ibid
12. Ibid, 24
13. Lewis, Miracles, 23
14. Ibid
15. Lewis, “The Funeral of a Great Myth,” in Christian Reflections, 91
16. Lewis, “Two Lectures,” in God in the Dock,
17. Lewis, The Problem of Pain, 68
18. Buber, I and Thou, (New York: Simon & Schuster, 1996)

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

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

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

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

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

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

And who created it? Was it the good Lord?

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

We are the only ones who say: cruelty.

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

Who cannot but feel and think,

Who is kindred to us by his warmth and movement,

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

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

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

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

The Problem

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

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

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

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

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

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

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

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

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

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

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

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

Notes

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

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

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

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

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

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

Lights, camera, actualization

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

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

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

Responding to the data

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

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

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

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

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

For further reading:

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

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

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

“Theistic evolution” has been discussed by that name since at least 1877, and one of the first to do so was the great Canadian geologist John W. Dawson, in his book, The Origin of the World, According to Revelation and Science (1877). In the midst of a lengthy discussion of the animals created on the fifth day of creation, he says:

The long time employed in the introduction of the lower animals, the use of the terms “make,” and “form,” instead of “create,” and the expression “let the waters bring forth,” may well be understood as countenancing some form of mediate creation, or of “creation by law,” or “theistic evolution,” as it has been termed; but they give no countenance to the idea either of the spontaneous evolution of living beings under the influence of merely physical causes and without creative intervention, or of the transmutation [evolution] of one kind of animal into another. (p. 225)

As the final part of this sentence implies, Dawson was (ironically) a staunch opponent of both human evolution and the common ancestry of other animals; in short, by no reasonable definition was he a theistic evolutionist, even though he thought that a great deal of change had taken place naturally, “within certain limits” that he associated with the created “kinds” spoken of in Genesis. Indeed, references to “theistic evolution” are probably no less common among opponents of the view (including William Jennings Bryan in the 1920s) than among proponents, but I won’t attempt to enumerate further examples.

In recent years, however, some proponents of TE have endorsed alternative labels for their position(s). The most prominent example is Francis Collins, the geneticist who started BioLogos. Collins uses the term “BioLogos” itself as the label for his overall position, which fits well within my TE category. The evangelical theologian Denis Lamoureux, one of the most qualified of all writers on this topic (he has earned doctorates in both theology and biology), strongly prefers the term, “Evolutionary Creation” (EC), precisely because he thinks the noun “creation” ought to have more emphasis than the adjective “evolutionary,” something that the term “theistic evolution” does not accomplish. I recommend his book of that title to anyone who wants an authoritative analysis of both biblical and scientific aspects of the origins controversy. The main ideas are clearly presented in his web lectures. Another highly qualified proponent of TE, George Murphy, also has reservations about the term, but he recognizes its wide recognition and agrees with the idea itself, that “Evolution is God’s way of creating”. I will have more to say about Murphy, a very important voice, in a subsequent post.

Despite these quite reasonable objections to the term, I continue to use the “TE” term, partly because it has historical continuity and I’m an historian, and partly because it’s easily recognized. If anyone wants to object, however, they won’t get objections from me, unless their own reasons aren’t reasonable. My only request: define your terms as clearly as I’ve defined mine.

Because the term is broad and a bit hazy, more should be said about it. When we talk about “Intelligent Design” next month, I’ll tell you that it’s a “big tent” (something proponents of that view also say), insofar as it glosses over the biblical and theological issues that have usually separated Christians into various “camps” (such as the various positions we are now studying) when it comes to origins. TE is also a “big tent,” in that adherents differ strongly amongst themselves on theological and biblical issues. Unlike ID, however, theology is openly discussed—and competing theologies of God, nature, and humanity are openly advocated, not left implicit. We’ll say more about this next time. This column presents one type of TE, a type favored by many evangelical scientists and scholars. For example, the people I will discuss all accept (as far as I can tell) the Incarnation and Resurrection—that is, they are Trinitarian Christians who believe that Jesus was fully divine (and fully human) and that the disciples went to the right tomb, only to find it empty, before encountering the risen Christ in diverse places. They also believe in creation ex nihilo, the classical view (illustrated at the start of this column) that God brought the universe into existence out of nothing. There are other types of TE, some of which are not (in my opinion) sufficiently biblical, or even sufficiently Christian, to be part of this series. Please keep that in mind as we proceed: don’t tar all TEs with the same brush—something that happens all too often elsewhere. Let knowledge, not ignorance, be our guide.

Core Tenets or Assumptions of Theistic Evolution

(1) The Bible is NOT a reliable source of scientific knowledge about the origin of the earth and the universe, including living things—because it was never intended to teach us about science.

This reflects not only modern scientific knowledge, but also (more importantly) modern biblical scholarship. Peter Enns and some other evangelical scholars have recently stressed this point, initiating a firestorm in the evangelical academic community that, so far, has confirmed my view that evangelicals in general are just not ready to deal with this, even though it is consistent with the classical notion of accommodation. My own comments about the magnitude of the problem, written before the firestorm started, can be found here.

(2) The Bible IS a reliable source of knowledge about God and spiritual things.

Remember the quip that Galileo attributed to Cesare, Cardinal Baronio, “The intention of the Holy Ghost is to teach us how one goes to heaven, not how heaven goes.” (We discussed this earlier in the series). Evolution was not an issue in Galileo’s day, but this platitude is frequently quoted by advocates of TE—and often without proper attribution to Baronio. Commonality obviously lies in the attitude, not the topic. Many critics of TE are willing to adopt Galileo’s approach when it comes to the Solar System, but not when it comes to evolution: they are anxious to keep Galileo out of the garden of Eden.

Portrait of Cesare, Cardinal Baronio,
attributed to Caravaggio (1602-3) (Source)

(3) Scientific evidence is irrelevant to the Bible—it is simply not a science book.

See above. This needs to be stated separately, since some believers look to science for “proof” of the Bible, just as some unbelievers look to science for “disproof.” Proponents of TE stress that science and the Bible aren’t like apples and oranges; rather, they are more like apples and rocks: you can hold one in each hand without tension, but they have very little in common. We wouldn’t look for God in the phone book, or in an automobile repair manual. Don’t look for science in the Bible. In principle, scientific theories neither support nor threaten the Bible.

(4) The creation story in Genesis 1 is a confession of faith in the true creator, intended to refute pantheism and polytheism, not to tell us how God actually created the world.

This is meant to echo what we said about the Framework View. It is not necessarily true that all TEs accept the Framework View or something like it, but many do. Most would probably say that the Bible is not contradicted by any specific scientific theory of biological diversity—unless that theory oversteps its philosophical boundaries and functions as a kind of religion, what Conrad Hyers called “dinosaur religion.”

(5) The Bible tells us THAT God created, not how God created

Again, this sounds like the Framework View—or, at least, it should. Belief in God the creator is consistent with science, and even supported by some aspects of science; but, it is not a substitute for scientific explanations.

An Assignment: It’s Your Turn to Read and Write

Astronomer Owen Gingerich has written an eloquent little TE book, God’s Universe. A number of quotations have been compiled here. My review for First Things identifies some of the key theological and philosophical issues related to TE. Please follow these links, study what you find, and offer comments below. If anyone has actually read the book itself, your views would be particularly valuable to include.

Looking Ahead

In our next column in two weeks, we continue our discussion of Theistic Evolution, focusing on some crucial theological aspects of TE. In the meantime, please do the “assignment” and get back to us.

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

Sporadic extinction

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

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

Extinction, en masse

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

Speciation, en masse

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

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

Clearing the deck, and re-filling the niches

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

For further reading:

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

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

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

The Evolutionary Role of Death & Natural Evil

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

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

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

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

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

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

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

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

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

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

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

Notes

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

No Football Coaches

When I explain this position to students, I like to start with a little puzzle. Many years ago, after attending an academic conference in a major city, I was driving through the rural countryside some distance away, en route to an historic house that wasn’t well marked. As I got closer to where I thought I might start seeing some signs directing me to the house, I noticed a fair-sized hotel, restaurant, and bar off to one side of the road. What really caught my attention was a sign, prominently displayed at the start of the driveway, warning off a certain clientele: NO FOOTBALL COACHES, it said. Unfortunately I’d forgotten my camera, but this is pretty much what I saw.

When I show it in class, I ask the students to guess what this was all about: why such a sign outside of such a place? The stories they come up with are pretty good. My favorite involves two neighboring high schools, arch rivals, with the football coach at one having an affair with the wife of his opposite number, resulting in fist-fights in that bar every fall, when friends of one man or the other would go at each other in the bar, which was on the highway connecting the two school districts. After a few students have tried their luck to no avail, someone asks, where did this take place? Was it maybe in England, where football means soccer and coach means bus? Give that student an A, I say. It was England, on a highway running between York and Manchester. Now, who can fill in the blanks? Almost right away, a student will explain that soccer fans in England can be pretty rambunctious, and that a busload of them might not make the best impression on the rest of the clientele at a respectable country inn and pub. Thus, the manager would rather not have their business.

The take-away message, of course, is that there is always a context in which the meaning of a text is embedded. Unless you know something about the time and place in which a text is composed, you aren’t going understand what it actually says. The same is true for any part of the Bible, including the opening verses of Genesis. That’s the bottom line for the Framework View: if you don’t know anything about literature and culture in the Ancient Near East, you won’t understand what Genesis is really saying.

Core Tenets or Assumptions of the Framework View

(1) The “days” in Genesis have nothing to do with historical time; they are literary devices, employed by God in order to communicate the story of the creation in terms that we can understand.

This sounds like an example of the principle of accommodation, and it should. The activities of the six days of creation are arranged into a “framework” of two triads (days 1-3 and days 4-6), with parallel types of activities in each triad.

Thus, light is created on the first “day,” and on the fourth “day” God makes the Sun and Moon, the two great lights in the firmament that produce light and “rule over” the day and the night. The air and sea appear on the second “day,” and on the fifth “day” God fills them with birds and fish, etc. In other words, the order of events seems to be more logical than chronological. The key element is the fourth day: as we noted in our discussion of Concordism, the Sun was not made until the fourth day, yet it was expressly given the task of producing the day and the night and we’ve had “evening and morning” since the first day. What’s going on here? How can this be taken “literally”? Advocates of the Framework view see a solution in the parallel triads.

Another way to see this focuses on the second verse in the Bible, which reads (in the American Standard Version, a translation that follows the Hebrew closely), “And the earth was waste and void; and darkness was upon the face of the deep: and the Spirit of God moved upon the face of the waters.” God is confronted by darkness, a watery abyss, and a formless earth—each of these features posing a problem for God, who deals with them in the subsequent six “days.” First, on “days” 1 to 3, God prepares the heavens and the Earth to be a home for the great creatures to come, by separating light from darkness, separating waters above the firmament from waters below the firmament, and causing the dry land to “appear” and to “put forth” vegetation. Then, on “days” 4 to 6, God makes the creatures and puts them in the places God has prepared—the Sun and Moon in the “firmament of heaven (day 4), birds in the air and fish in the seas (day 5), and finally “the beasts of the earth” and “man” on the land (day 6).

We emphasize that the Framework View is simply about the Bible, not about science. The Earth and the universe can be as “young” or “old” as anyone wishes to claim, because the literary form of early Genesis leaves this an open question. The “days” were probably meant to be understood “literally” as ordinary days, but only in the context of a literary form that was not meant to be understood literally, when taken as a whole.

What about the seventh “day”? Because it lacks a “morning” and an “evening” in the text (have you ever noticed this?), some authors interpret the seventh “day” as a prophetic reference to God’s own eternal rest, which has not yet begun and which we will share with God in the eschatological future. An OEC book I discussed in my column on Concordism, Robert Newman’s Genesis One and the Origin of the Earth (1977), advocates this interpretation (see pp. 65-66), and so do some advocates of the Framework View.

(2) When seen against the cultural and literary context of the Ancient Near East (ANE), it is clear that Genesis was written to combat the polytheism and pantheism of other creation stories. It was not written to provide a scientifically accurate account of the creation.

This is why the Sun and Moon are not even named on the fourth day: they were worshipped as divine beings by many people in the ANE, and the Hebrew author(s) of Genesis intentionally omit their names as an act of defiance against worshippers of those two false gods. (Remember: for the ancient Egyptians, the Sun was the chief god.) Furthermore, the stars are mentioned simply as an afterthought, at the end of verse 16: “And God made the two great lights; the greater light to rule the day, and the lesser light to rule the night: he made the stars also.” This was done deliberately, as a way of belittling the Babylonians and others who worshipped them. Indeed, the whole creation account stands in the face of polytheism, by affirming that the one true, invisible God has actually created all visible things, including the heavenly bodies. Nothing we see is divine: this is the essence of monotheism, stated bluntly and boldly.

(3) It is not possible to find a close match between what is proclaimed in Genesis—that God is the creator—and the details of natural history. We should not approach this text with inappropriate expectations.

For many readers, the crucial question awaits: according to the Framework View, is Genesis 1-3 historical in any meaningful sense? Here there is a division of the house, with authors falling into either of these two camps:

(1) Genesis 1-3 is an historical narrative (though not strictly chronological), not a creation myth. As Lee Irons and Meredith Kline emphasize in The G3N3S1S Debate, “The framework interpretation does not teach that creation was a nonhistorical event” (p. 220). The universe was actually created, Adam and Eve were the first humans, and the Fall was a real historical event. Some OECs like this approach, which can be seen as a looser type of Concordism than the day-age theory; Bernard Ramm’s “moderate concordism” might be understood as fitting into this category, even though he did not discuss the Framework View per se.

(2) Genesis 1-3 is not an historical narrative; it resembles some other, older ANE creation stories. Conrad Hyers advances this view in his book, The Meaning of Creation: Genesis and Modern Science ; see below. Some aspects of the story reflect this: the days, the progression from chaos to order, and the creation of humans from mud or clay. These are common to other ANE stories, and they are present in Genesis because that’s what hearers in the ANE expected such stories to include. Other aspects of Genesis, however, are profoundly unlike other ANE stories: the transcendence of God and the de-deification of nature. These constitute the crucial, timeless, substantive message that God has revealed to us. Theistic evolutionists tend to like this non-historical approach, which is not usually seen as a kind of Concordism.

Historical Comments

The Framework View is modern, but its attitude toward the Genesis “days” is similar to that held by Augustine. As I explained in an earlier column, he taught that God created all things at once and told us about it in the pattern of six days, in order that we could understand it. The days themselves, however, were “unknowable” and not meant as a “literal” description of the passage of time.

In the 19th century, the German scholar J. H. Kurtz put forth an interpretation that Ramm called the “pictorial day” view, which he considered to be a type of “Moderate Concordism,” the overall position that Ramm himself favored. Kurtz described the creation story as “prophetico-historical tableaux, [in] which are represented before the eye of the mind, scenes from the creative activity of God, each one of which represents some grand division of the great drama, some prominent phase of the development” (The Bible and Astronomy, 1861 Philadelphia edition, p. 110). His Scottish contemporary Hugh Miller, one of the most prolific and influential evangelical writers of his day, endorsed Kurtz’ interpretation, holding that “the form and nature of the revelation” in Genesis was “conveyed by a succession of sublime visions” (The Testimony of the Rocks, 1857 Boston edition, p. 180).

The Framework View itself, with the “days” arranged in parallel triads, was first proposed in 1924 by the Dutch scholar Arie Noordzij and made more widely known by another Dutch scholar, N. H. Ridderbos. His book—Is There a Conflict Between Genesis 1 and Natural Science?—was translated into English in 1957. Subsequently, Kline and the French theologian Henri Blocher have been its most prominent supporters.

An Assignment: It’s Your Turn to Read and Write

I’ve done most of the heavy lifting in this series, but now it’s your turn. As a way of getting into all three of the views we’ve studied thus far (not simply the Framework View), I’d like everyone to read an article by Conrad Hyers, “Dinosaur Religion: On Interpreting and Misinterpreting the Creation Texts,” Journal of the American Scientific Affiliation 36 (September 1984): 142-48. The questions below are intended as helpful suggestions; feel free to discuss other matters as well!

1. What does Hyers mean by “dinosaur religion”?

2. What is Hyers’ most basic objection to “creation science,” the YEC view?

3. What does Hyers believe to be the true message of Genesis One?

4. Overall, do you agree with what Hyers says? Why or why not? Whether or not you agree, do you have any critical comments?

NOTE: Hyers wrote a sequel, “The Narrative Form of Genesis 1: Cosmogonic, Yes; Scientific, No,” Journal of the American Scientific Affiliation 36 (December 1984): 208-15, in which he employs an interpretive scheme highly similar to the Framework View, although that term is not used. I encourage you to read this also, but our discussion will focus on the first article.

Looking Ahead

In our next column on August 14, we begin a lengthy discussion of Theistic Evolution. Although that is the view advocated (under an alternative name) by BioLogos, I will approach it no differently. After explaining its central tenets, we’ll examine them critically and outline its history. Between now and then, I’m keen to see your responses to the assigned reading. If you gotten this far, you’re more than just a casual reader. Tell us what you think of Hyers’ ideas.

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

Review: gene structure and function

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

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

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

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

Comparing gene transcription across species at the genomic level

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

Old hypotheses, new technology

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

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

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

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

These results underscore a few important points:

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

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

For further reading:

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

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

In his book The Greatest Show on Earth (2009) on the first page of the second chapter, Dawkins raises the interesting question: “Why did it take so long for a Darwin to arrive on the scene?” After suggesting possible answers he approvingly quotes the late Ernest Mayr's suspicion as the most insightful answer to this question. According to Dawkins, Mayr’s suspicion is: “The culprit was the ancient philosophical doctrine of---to give it its modern name—essentialism. The discovery of evolution was held back by the dead hand of Plato [Dawkins' language].” Later in his book, Dawkins states boldly that evolution is anti-essentialist, a point Mayr made in other places. One can find the same argument, if not the same language, in the writings of Edward O. Wilson where the idea of nature trumps any idea of something existing above experience. Clearly, I am not the first one to consider this argument. I think, however, that further discussion regarding the implications of essentialism for evolutionary models remains important especially for theists in particular and humanity in general. At the heart of this discussion is the matter of ontology, the nature of being. While evolution speaks to the development of what is, it necessarily carries with it very strong ontological implications, implications that affect views on the nature of being. If the idea of essence has no currency in the discussion of reality, then the thing itself is all there is and, hence, quickly becomes the object complete in itself.

It seems that essentialism (I use this term with Christian emphasis), if true, would seriously challenge any form of evolution where different species evolve through common descent. The point that Mayr and others have made turns on the idea that essentialism provided the philosophical foundation for the idea of fixity of species from at least the time of Plato. If right, that would make evolution, in the sense of producing new species, suspicious if not impossible. Furthermore, it seems that essentialism cannot be easily dismissed simply because it is associated with Plato. One must consider the philosophical/theological legitimacy of essentialism based on the merits of its own claims within the discussion of the nature of reality. With that said, if Mayr and others are right about essentialism, then the question to be taken up is whether essentialism has any ground upon which to stand, especially within Christian theology.

Generally speaking, essentialism teaches there is more to reality of the thing than what is presented to the senses which, is to say there is more to reality than the biological dimension (we might say DNA). It is the material that provides a means of expression of the essence. A member belonging to a natural kind is so because of its essence and all members belonging to this natural kind must have this essence or it does not belong. In this way, natural kinds are distinct from others by virtue of their essence. While essence determines what natural kind to which a thing belongs, there are also non-essential or accidental properties. These help to distinguish one member from another within a natural kind, but these are not determinative for the natural kind itself as they are subject to change while essential properties are not. That is, what makes a cow a cow is the essence belonging to being a cow. Without that, the cow could not be a cow. In other words the idea of essence is what gives stability to natural kinds. If essentialism is true this would, as Dawkins points out, seriously challenge the idea of common ancestry.

Applied to human beings, the essential attributes of humanness are predicated of beings called human beings which distinguishes them from non-human beings –this is not an arbitrary naming. While human beings (a natural kind) share universally the same essence of humanness, they do differ in non-essential properties (short, tall, thin, fat, and so forth). So while the members differ in many non-essential ways, they belong to the same natural kind by their shared essential attributes of humanness.

If what has been called an essence (Plato referred to these as Forms and Augustine as Ideas in the mind of God or eternal reason) explains natural kinds, it is easy to see how this would logically lead to the idea of fixity of species (which may be very broad allowing for a wide range of adaptations and variations within natural kinds which allows for a very rich biological diversity). The suggestion here is that it is time to rethink the matter of essentialism in this discussion. Of course there must be some reason to think that essentialism has merit on its own terms.

The fact that a being is determined by its essence finds support in understanding who Jesus is. Consider what makes Jesus the God-Man. As argued by the early Church Councils, it was His nature (in Greek, OUISA). He had the nature of both---the essence of God and the essence of man. It was not that He had all the outward appearance and DNA function of a man that made him a man---it was more than that. He was a man, precisely because He possessed the nature (essence of a man) and He was God as He had the nature (essence of God). This at least supports the idea that a being is what it is, not by virtue of developmental issues, but because of its essence.

In thinking about essence, one might consider the matter of transubstantiation. One may discount transubstantiation on theological grounds, but it does say something interesting to the discussion of essentialism. It assumes that the bread is of one essence and the body is of another essence. In order for the wine to become blood (a different essence) it would take a miracle as one essence does not give way to a different essence in the process of nature. The idea of transubstantiation is discussed in Aristotelian categories; in this case substantive cause is what Aristotle meant by the whatness of a thing–that is, what makes it what it is. Additionally, Genesis 1:20 notes that living creatures were created according to their own kind (the whatness of the thing) supporting the idea of natural kinds, which is consistent with the idea of fixity of species.

Tomorrow in part 2, Dr. Little makes the case that modern science has unjustifiably marginalized essentialism because it does not fit within a purely physical understanding of reality.

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

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

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

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

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

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

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

Common Descent

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

Natural Selection

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

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

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

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

Furthermore, he also writes:

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

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

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

Human Continuity

Dembski quotes from Darwin’s Descent of Man:

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

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

Methodological Naturalism

Dembski defines methodological naturalism in the following way:

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

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

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

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

For further reading:

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

(Click Image for Full Resolution)

Evolution: just a theory

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

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

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

Whale evolution: an example of converging lines of evidence

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

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

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

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

Going out on a limb

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

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

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

… and passing the test

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

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

For further reading

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

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

In our last two BioLogos podcasts, we looked at the question of transitional fossils and the genetic evidence for evolution. In our final installment of this three part series, we move on to the question of speciation and macroevolution. A common challenge to evolutionary theory is that while life does indeed change over time (what is known as microevolution), no one has ever seen one species evolve into another species (macroevolution). For example, no one has seen a dog evolve into something other than a dog. Because speciation has never been observed, and because science is based on observation, evolution cannot be considered scientific.

In fact, examples of speciation have been observed by scientists. We must also remember that we are able to observe just a tiny window of the long history of life on Earth, and the fact that any speciation has been noted at all is impressive indeed.

Transcript

It’s pretty clear to most of us that life can change over time. For those who aren’t convinced, just take a quick trip to your local animal shelter. Each of the dog breeds there, from the Great Dane to the Chihuahua, descended from a single ancestral population. As you probably already know, that ancestral group was a wolf-like species. -How did these drastic changes take place? Well, basically, genetic variation within that original population was acted upon by selective forces. Now, just to be clear, the selection at work here wasn’t natural. It was the result of breeding done over hundreds of years. But the basic principle is the same. Genetic variation plus some sort of selection results in genetic change. This is evolution.

For the most part we are ok with accepting this. Yet many people still have a problem with the Theory of Evolution. Those suspicious of evolutionary Theory generally split evolution into two categories. Instead of arguing that evolution is completely impossible, they will say something like, “I know microevolution is real, but I just can’t accept macroevolution.”

Kent Hovind, an especially outspoken opponent of evolutionary theory, often makes this argument in his presentations:

“Maybe you’re talking about macroevolution. That’s where an animal changes into a different kind of animal. Nobody’s ever seen that. Nobody’s seen a dog produce a non-dog. I mean you may get a big dog or a little dog, I understand, but you’re going to get a dog, okay?” (source)

But what does this mean? What is the difference between micro and macroevolution anyway, and why is one of them ok while the other is condemned?

Well, like many terms used in the evolution debate, the definitions tend to differ depending on who you talk to. This can make rational discussion difficult. Most opponents of evolution, like Kent Hovind, say that macroevolution refers to one “type” or “kind” of organism evolving into another “kind”. Microevolution, they might say, is evolution within a “kind”. Evolution of one dog breed into another, they would say, is microevolution. Evolution of a “dog into a non-dog”, as Hovind puts it, would be “macroevolution.”’

One big problem with this argument is that “kind” is not clearly defined. It is a subjective term referring to organisms that seem similar to each other. Now, this is a definition that can easily be manipulated. And it doesn’t work very well when asking scientific questions. Because there is disagreement about what they actually mean, the terms micro and macroevolution aren’t often used in scientific literature. But when biologists do refer to “macroevolution”, most define it as “evolution above the species level”.

(Sources: http://ib.berkeley.edu/courses/ib200a/lect/ib200a_lect26_Lindberg_macroevolution.pdf, http://www.nescent.org/media/NABT/, http://evolution.berkeley.edu/evosite/evo101/VIADefinition.shtml, http://www.nhm.ac.uk/hosted_sites/paleonet/paleo21/mevolution.html)

In other words, at the smallest scale, macroevolution is the development of a new species. This definition is more useful because you can objectively determine whether two organisms are members the same species, but “kind” has no specific definition.

So what does “species” mean anyway? How is it different from “kind?” Well, the term species can be hard to define. Life is complex, and categorizing it into clear groups can be tricky. The currently accepted definition of species comes from what we call the “biological species concept.” Basically, the biological species concept says that a species is made of populations that actually or potentially interbreed in nature.

So, two populations that cannot mate to produce successful offspring are by definition separate species. Now, this definition doesn’t always work. For example, when you have a species that reproduces asexually, finding the boundaries between species can be a little tricky. But in most cases it does a pretty good job. It’s a good way to objectively determine where one species stops and another one begins.

The Biological Species Concept is especially useful when you have two species that look and act very similar. Eastern and Western Meadowlarks are a good example of this. They look almost exactly the same. But they cannot interbreed successfully. Therefore, they are separate species. This definition also helps when we study evolution. Where can we draw the line between microevolution and macroevolution? Well, it’s never easy, but having a working definition of this thing called a species helps out a lot. When enough genetic changes accumulate in a population, eventually it loses the ability to mate with others of its species. Then, by definition, it becomes a new species. In other words, macroevolution has occurred.

As we just discussed, many critics claim that macroevolution can never happen—one species can never cross over to become another one. This statement might sound valid, but a little bit of investigation shows that it is not well supported by evidence. For one thing, the only difference between micro and macroevolution is scope. When enough micro changes accumulate, a population will eventually lose its ability to interbreed with other members of its species. At this point, we say that macroevolution has occurred.

The same processes—random mutation and natural selection—cause both micro and macro evolution. There are no invisible boundaries that prevent organisms from evolving into new species. It just takes time. Usually, the amount time required for macroevolution to occur is significant—on the order of thousands or millions of years. That’s why you don’t normally see brand new forms of life appear every time you step out your front door. And that’s also why some people think that speciation never happens at all.

But sometimes macroevolution doesn’t take that much time. In fact, the evolution of new species sometimes happens so quickly that we can actually see it take place! Let’s look at a few recent examples.

Biologists Peter and Rosemary Grant had been studying finches since 1973. They lived on an island called Daphne Major in the Galapagos. It was here that they conducted their studies. When they first began their studies, only two species of Finch lived on Daphne Major: the medium ground finch and the cactus finch. But, in 1981, Peter and Rosemary noticed that an odd new finch had immigrated to the island. It was a hybrid, a mix between a cactus finch and a medium ground finch. It didn’t quite fit in with the other birds. The odd misfit had an extra large beak, an unusual hybrid genome, and a new kind of song. But somehow he was still able to find a mate. The female was also a bit of a misfit and had some hybrid chromosomes of her own. So their offspring were very different from the other birds on the island.

Rosemary and Peter continued to carefully watch the odd hybrid line. They wondered if the birds would become isolated from the other finch species on the island or if they would eventually re-assimilate. After four finch generations, a drought killed off many of the birds on Daphne Major. In fact, almost the entire hybrid line was exterminated. Only a brother and sister pair remained. The two family members mated with each other, producing offspring that were even more unique than their parent line. From that point on, as far as biologists Peter and Rosemary could tell, the odd population of finches mated only with each other. They were never seen to breed with the cactus finches or the medium ground finches on the island. The finches with the strange song had become a brand new species.

(Source: http://www.pnas.org/content/106/48/20141.full)

Another example of speciation, or macroevolution, also took place on an island—this time, on the beautiful Portuguese island of Madeira. According to history books, the Island of Madeira was colonized by the Portuguese about 600 years ago. The colonizers brought with them a few unassuming European House Mice, which they accidentally left on the island. It’s also possible that a group of Portuguese House Mice was dropped off later on.

Recently, Britton-Davidian, an evolutionary biologist at University Montpellier 2 in France, decided to collect samples of the Madeira mice and see how those original populations had changed over time. What she found was surprising. Rather than just one or two species of mouse, she found several. In only a few hundred years, the original populations of Mice had separated into six genetically unique species. The first mouse populations had 40 chromosomes altogether. But the new ones were quite different. Each new variety had its own unique combination of chromosomes, which ranged in number from 22 to 30.

What seems to have happened is that, over time, the mice spread out across the island and split into separate groups. Madeira is a rugged volcanic island with crags and cliffs. So it makes sense that this would have been easy to do. There were many isolated corners for the mice to occupy. Over time, random mutations occurred—some chromosomes became fused together.

Now, In order to reproduce successfully, both parents must have the same number of chromosomes. So when a population develops a chromosome fusion, suddenly that group cannot mate with the other members of its species. It becomes a brand new species. That’s exactly what happened on Madeira. And because of this phenomenon, 6 new species evolved from just 1 or 2 in an extremely short amount of time.

(Sources: http://onlinelibrary.wiley.com/doi/10.1111/j.1365-294X.2009.04345.x/full, http://www.genomenewsnetwork.org/articles/04_00/island_mice.shtml, http://www.nature.com/hdy/journal/v99/n4/full/6801021a.html)

Another fascinating example of macroevolution was recently observed by researchers at Pennsylvania State University. This time, two species combined to make a single new one. In 1997, researchers at Penn State noticed a fruit maggot infestation on some recently introduced Asian Honeysuckle bushes. They decided to investigate the Honeysuckle fly population and determine how it was related to the other flies nearby. When they examined the honeysuckle fly’s genes, the researchers discovered something interesting. The fly appeared to be a hybrid of two native species—the blueberry fly and the snowberry fly.

But the honeysuckle fly’s genetic material was not an exact balance between that of the two parent species. The ratios of DNA varied from fly to fly. This showed the researchers that the honeysuckle flies had been breeding amongst themselves for many generations—probably at least 100. Also, they found that the Honeysuckle Flies were very unlikely to breed with any other species. They bred only on their host Honeysuckle plants. So they weren’t likely to mix with flies that lived on a different host.

According to Dr. Dietmar Schwarz, post-doctoral researcher in entomology, as far as the researchers can tell, “The new species is already reproductively isolated. They seem to be in a niche on the brushy honeysuckle where the parent species cannot compete."

(Source: http://www.psiee.psu.edu/news/2005_news/july_2005/hybrid_insects.asp)

While this kind of speciation—two species hybridizing to create a new one—seems odd, it is a significant mechanism of macroevolution. And it’s especially common in plants. In fact, a new species of weed recently arose this way in Great Britain. In 1991, Richard Abbot, a plant evolutionary biologist from St. Andrews University, noticed an unusual weed growing next to a car park in York. He discovered that the species, an unassuming scruffy weed, was a natural hybrid between the common groundsel and the Oxford ragwort, a plant that was introduced to Britain only 300 years ago. The York Groundsel lives in a different niche, or microenvironment, than either of its parent species. It is able to breed and reproduce, but only with other York Groundsel plants. It cannot successfully reproduce with any other species, including either of its parent plants. Thus, by definition, the York Groundsel is its own new species.

(Sources: http://www.nerc.ac.uk/publications/planetearth/2003/summer/sum03-evolution.pdf, http://www.nature.com/hdy/journal/v69/n5/abs/hdy1992147a.html)

So, as we have seen, macroevolution is an established process. Usually it takes thousands of years to occur, but sometimes we get lucky and catch it in the act. When Kent Hovind said that, “no one has ever seen a dog produce a non-dog” he was technically quite correct. But this statement infers that macroevolution means a drastic and obvious change from one type of organism into another. Those who think this way believe that macroevolution is something like two dogs breeding to suddenly produce a cat, or two guinea pigs mating to produce a mouse.

But this is not how evolution works at all. Over millions of years, a dog-like animal may indeed evolve into a something that looks completely unlike a dog. However, this is not something that we would expect to be able to observe. It just takes too much time. To put the scale of evolution into perspective, consider this. If the average lifespan of a United Stated citizen, 78 years, were a single minute, then single-celled life has been around for nearly 100 years. On this scale, all we get to see is one minute. And even in that time frame we sometimes see new species forming. God’s time is not our time and we tend to forget this. What we do expect to observe is a very slow step-by-step accumulation of tiny genetic changes that eventually result in speciation. And indeed, as we discussed today, this is exactly the sort of evidence revealed in nature.

So, macroevolution is not a “myth” by any means. It is supported by a vast amount of evidence. That evidence includes the fossil record and genetics, as discussed in previous BioLogos podcasts, and, when we get lucky, direct observation of speciation. God, being who God is, could conceivably have created species out of thin air in a single instant. But what if instead if God created and sustained the process by which new species are created? Does that make him less powerful or less "god-like"? Is it somehow more God’s process if it happened in an instant, than it is if it happened over a long period of time? Presumably even if it happened in an instant, it would still happen by some sort of process—only faster.

God’s time is not our time, and perhaps it’s a good idea for all of us to simply stand back in amazement while God does God’s work in God’s time through God’s process.