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. 

A few months ago, I provided an overview of Polkinghorne’s views on natural theology. However, perhaps the best place to get acquainted with his position is to read the title chapter from his book, Belief in God in an Age of Science. First delivered as the Terry Lectures at Yale University in October 1996, this eloquent little book contains five chapters and a short epilogue. Readers are invited to explore the rest of the book on their own. I especially recommend the highly original second chapter (“Finding Truth: Science and Religion Compared”), in which he compares the ways in which physicists struggled to understand the dual nature of light (as a wave or a particle) in the early twentieth century with the ways in which early Christian thinkers struggled to understand the dual nature of Jesus (as divine and human). Unfortunately we won’t be presenting additional chapters here, but neither the print nor the electronic version of the book is very expensive!

In the fourth sentence below, Polkinghorne defines “belief in God” in terms of the proposition “that there is a Mind and a Purpose behind the history of the universe.”  This excerpt presents some evidence for a divine mind behind the visible world revealed to us by science, while the next (coming in about two weeks) discusses some evidence for divine purpose.

My editorial policy for these excerpts is explained at the bottom of this post.

Belief in God in an Age of Science (part 1)

What does it mean to believe in God today? Different religious communities propose different answers to that fundamental question. I speak from within the Christian tradition, though much of what I say in this chapter would, I believe, find endorsement from my Jewish and Islamic friends. For me, the fundamental content of belief in God is that there is a Mind and a Purpose behind the history of the universe and that the One whose veiled presence is intimated in this way is worthy of worship and the ground of hope. In this chapter, I sketch some of the considerations that persuade me that this is the case.

The world is not full of items stamped “made by God”—the Creator is more subtle than that—but there are two locations where general hints of the divine presence might be expected to be seen most clearly. One is the vast cosmos itself, with its fifteen-billion-year history of evolving development following the big bang. The other is the “thinking reed” of humanity, so insignificant in physical scale but, as Pascal said, superior to all the stars because it alone knows them and itself. The universe and the means by which that universe has become marvelously self-aware—these are the centers of our enquiry.

Paul Dirac (source)

Those who work in fundamental physics encounter a world whose large-scale structure (as described by cosmology) and small-scale process (as described by quantum theory) are alike characterized by a wonderful order that is expressible in concise and elegant mathematical terms. The distinguished theoretical physicist Paul Dirac, who was not a conventionally religious man, was once asked what was his fundamental belief. He strode to a blackboard and wrote that the laws of nature should be expressed in beautiful equations. [Remember that Polkinghorne was a student in Dirac’s lectures on quantum physics; see here.] It was a fitting affirmation by one whose fundamental discoveries had all come from his dedicated pursuit of mathematical beauty. This use of abstract mathematics as a technique of physical discovery points to a very deep fact about the nature of the universe that we inhabit, and to the remarkable conformity of our human minds to its patterning. We live in a world whose physical fabric is endowed with transparent rational beauty.

Attempts have been made to explain away this fact. No one would deny, of course, that evolutionary necessity will have molded our ability for thinking in ways that will ensure its adequacy for understanding the world around us, at least to the extent that is demanded by pressures for survival. Yet our surplus intellectual capacity, enabling us to comprehend the microworld of quarks and gluons and the macroworld of big bang cosmology, is on such a scale that it beggars belief that this is simply a fortunate by-product of the struggle for life. Remember that Sherlock Holmes told a shocked Dr. Watson that he didn't care whether the Earth went round the Sun or vice versa, for it had no relevance to the pursuits of his daily life!

Even less plausible, in my view, is the claim sometimes advanced that human beings happen to like mathematical reasoning and so they manipulate their account of physical process into pleasing mathematical shapes. [Polkinghorne cites Andrew Pickering, Constructing Quarks, p. 413] Nature is not so plastic as to be subject to our whim in this way. In 1907, Einstein had what he called “the happiest thought of my life,” when he recognized the principle of equivalence, which implied that all entities would move in the same way in a gravitational field. This universality of effect meant that gravity could be expressed as a property of space-time itself; physics could be turned into geometry. Einstein then embarked on a search for a beautiful equation that would determine the relevant geometrical structure. It took him eight years to find it, culminating in the discovery of the theory of general relativity in November 1915. It was a truly beautiful theory but now came the moment of truth. On 18th November, Einstein calculated the prediction made by his theory for the motion of the planet Mercury. He found that it precisely explained a discrepancy in relation to Newton’s theory that had baffled astronomers for more than sixty years. Einstein’s biographer, Abram Pais, says “This discovery was, I believe, by far the strongest emotional experience in Einstein’s scientific life, perhaps in all his life. Nature had spoken to him.” Whilst the great man himself said, “For a few days, I was beside myself with joyous excitement.” [Abraham Pais, Subtle is the Lord: The Science and the Life of Albert Einstein, p. 253]. It was a great triumph but, if the answer had not come out right, the aesthetic power of the equations of general relativity would have been quite unable in itself to save them from abandonment. It was indeed nature that had spoken.

There is no a priori reason why beautiful equations should prove to be the clue to understanding nature; why fundamental physics should be possible; why our minds should have such ready access to the deep structure of the universe. It is a contingent fact that this is true of us and of our world, but it does not seem sufficient simply to regard it as a happy accident. Surely it is a significant insight into the nature of reality. I believe that Dirac and Einstein, in making their great discoveries, were participating in an encounter with the divine.

Old French Bible moralisée (c. 1208-15), Codex Vindobonensis 2554,
fol. lv, Österreichische Nationalbibliothek (source)

It has become common coinage with contemporary writers about science to invoke, in addressing the general public, the idea of a reading of the Mind of God. [Polkinghorne cites Paul Davies, The Mind of God and Stephen Hawking, A Brief History of Time.] It is a small, but significant, sign of the human longing for God that apparently this language helps to sell books. There is much more to the Mind of God than physics will ever disclose, but this usage is not misleading, for I believe that the rational beauty of the cosmos indeed reflects the Mind that holds it in being. The “unreasonable effectiveness of mathematics” in uncovering the structure of the physical world (to use Eugene Wigner’s pregnant phrase) is a hint of the presence of the Creator, given to us creatures who are made in the divine image. I do not present this conclusion as a logical demonstration—we are in a realm of metaphysical discourse where such certainty is not available either to believer or to unbeliever—but I do present it as a coherent and intellectually satisfying understanding.

Looking Ahead

We continue with the excerpt on purpose in about two weeks.

References and Credits

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

Editorial Policy

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

Such remnants are also found in our genomes.  Humans, unlike most mammals, cannot synthesize (make) our own vitamin C, but we carry the genes for synthesizing vitamin C.  One of these genes encodes the GLO (L-gulonolactone oxidase) enzyme, and this gene in humans contains inactivating mutations and is therefore a “pseudogene.”  This pseudogene and the genes that encode the enzymes of the vitamin C biosynthetic pathway are the remnants of our own evolutionary lineage from an ancestor that was able to synthesize its own vitamin C.⁴ Furthermore, the GLO pseudogene is just one of a graveyard of inactivated genes, transposons, retroviruses and other non-functional sequences that litter our genome.  While some of these sequences have been co-opted for particular functions, many of them have no known function.⁵ We share many of these non-functional sequences with chimpanzees.  The very presence of these genomic and anatomical flotsam and jetsam only makes sense if evolution has occurred.⁶

A third piece of evidence for evolution comes from biogeography.⁷ The flora and fauna of islands such as those of the Galápagos and Hawaii are radically unbalanced in that they lack many types of plants and animals but contain a profusion of clusters of similar species.  Hawaii, for example, has no native mammals, reptiles, or amphibians, but a profusion of fruit flies and silversword plants.⁸ One third of the 2,000 species of fruit flies are found on the Hawaiian Islands, which only covers 2 percent of the land on earth.  These islands were never connected to the continents and arose as a result of volcanic activity and were, at least initially, completely uncolonized.  The colonization of these islands occurred by means of occasional introduction of creatures from the mainland that then rapidly speciated on these islands to fill every available ecological niche.  Thus, the organisms most closely related to island species come from the closest mainland areas, and often include those creatures most likely to find their way to islands, such as birds and flying insects. 

The Galápagos Islands provide an excellent example of how biogeography provides evidence for evolution. The Galápagos have fourteen species of finch whose closest relative is probably the South American grassquit (Tiaris), yet only four of these finch species feed on seeds as finches normally do, while two others feed on cacti, seven eat insects, and another eats almost exclusively leaves.⁹ Darwin, while visiting the Galápagos, still thought that species only varied within a particular kind (though he would not have used that terminology) but could adapt to various local environments and become particular subspecies. Therefore, he originally listed the warbler finch (Certhidea olivacea) as a wren and listed the small cactus finch (Geospiza scandens) as a member of the Icteridae or the family of meadowlarks and orioles.  Only after Darwin had deposited his Galápagos specimens with the British ornithologist John Gould did Darwin discover (in a meeting with Gould that occurred during March, 1877), that his finch collection included thirteen or fourteen species of unusual finches that were all so closely related, Gould classified them in a single group all their own.  This meeting showed Darwin that the immutable barrier between kinds of species did not exist.  The Galápagos Islands were not a distinct “center of creation,” but a workshop for evolution in which an ancestral species made it to the yet uncolonized island and underwent a massive degree of speciation to adapt to the environment of the island.¹⁰ This is precisely what one would expect if the species of islands had arisen by evolution. 

A scientific theory also allows scientists to make predictions, and good theories provide accurate predictions.  Can the theory of evolution allow accurate predictions?  The answer, once again, is yes.  Darwin himself predicted that the earth must be very old for evolution to occur.  He did not know the age of the earth, but further research has shown that the earth is 4.55 billion years old, which is plenty of time for evolution to occur.  Darwin also predicted that since plants on islands were most closely related to certain mainland plant species, the seeds of these plants should be able to withstand immersion in sea water for long periods of time, and again, Darwin was shown to be right.¹¹ Many decades after Darwin, we now know that variation in organisms is due to mutations in DNA and that these mutations are inherited, just as Darwin predicted.¹² Also, Darwin’s principle of natural selection predicts that particular sequences of DNA should behave in a manner that benefits only themselves and not their carriers, which modern research has thoroughly confirmed with the discovery of transposons and other types of “selfish DNA.”¹³

Is evolutionary theory a good scientific theory?  It has been repeatedly tested for over 150 years since its inception, and it has passed those tests successfully.  The theory has been modified in response to new data, but the outlines of the theory have remained largely intact.  It has existed at risk from new data.  During the molecular biology revolution that began with the discovery of the structure of DNA by Franklin, Watson and Crick in 1953, the explosion of new data could have shown contemporary evolutionary theory to be wrong.  However, some of the most powerful evidence for the theory of evolution has come from a field of science that did not even exist during Darwin’s time.  The ability of a theory to withstand such intense scrutiny is a clear sign it is robust and enduring.  As shown, the theory of evolution has predictive power, and it also integrates and makes sense of data from several fields of science, including ecology, paleontology, genetics, historical geology, paleoclimatology, and comparative anatomy and biochemistry.  The highly integrative nature of evolutionary theory makes it a fine theory by any measure. 

In conclusion, when measured against the standards of a good scientific theory, modern evolutionary biology clearly qualifies as good science.  Ongoing debates within evolutionary biology exist about mechanism, rates, and causes, but not over whether evolution occurred.  Such a question has been largely settled by the last 150 years’ worth of research.  The future certainly looks bright for this field of science and I cannot imagine a more exciting topic to study. 

Notes

1. Davit-Béal, Tiphaine,Abigail S. Tucker, and Jean-Yves Sire. “Loss of Teeth and Enamel in Tetrapods: Fossil Record, Genetic Data and Morphological Adaptations.” Journal of Anatomy 214, no. 4 (2009): 477–501. 

2. Tian, Natasha M. M.-L., and David J. Price. “Why Cavefish are Blind.” BioEssays 27 (2005): 235–38; Yamamoto Y, Stock DW, and Jeffery WR (2004) Hedgehog Signalling Controls Eye Degeneration in Blind Cavefish. Nature 431:844–7; Jeffery, W. R. “Adaptive Evolution of Eye Degeneration in the Mexican Blind Cavefish.” Journal of Heredity 96, no. 3 (2005): 185–196. 

3. Bejder, L., and B. K. Hall. “Limbs in Whales and Limblessness in Other Vertebrates: Mechanisms of Evolutionary and Developmental Transformation and Loss.” Evolution and Development 4, no. 6 (2002): 445–58. 

4. Lachapelle, M. Y., and G. Drouin. “Inactivation Dates of the Human and Guinea Pig Vitamin C Genes.” Genetica 139, no. 2 (2011): 199–207.

5. Avise, John C. Inside the Human Genome: A Case for Non-Intelligent Design. New York: Oxford University Press, 2010.   Romano, C. M., F. L. Melo, M. A. Corsini, E. C. Homes, and P. M. Zanotto.  “Demographic Histories of ERV-K in Humans, Chimpanzees and Rhesus Monkeys.” PLoS One 2, no. 10 (2007): e1026. http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0001026. 

6. Max, “Plagiarized Errors and Molecular Genetics,” http://www.talkorigins.org/faqs/molgen.

7. Coyne, Jerry A. “Intelligent Design: The Faith that Dare Not Peak Its Name.” In Intelligent Thought: Science Versus the Intelligent Design Movement, edited by John Brockman, 3–23. New York: Vintage, 2006. 

8. Kricher, John. Galápagos: A Natural History. Princeton, NJ:  Princeton University Press, 2006. 

9. Grant, Peter R., and Rosemary B. Grant. How and Why Species Multiply: The Radiation of Darwin’s Finches. Princeton, NJ: Princeton University Press, 2011. 

10. Sulloway, Frank J. “Why Darwin Rejected Intelligent Design.” In Intelligent Thought: Science Versus the Intelligent Design Movement, edited by John Brockman, 107–25. New York: Vintage, 2006. 

11. Darwin, Charles. “On the action of sea-water on the germination of seeds.” Journal of Proceedings of the Linnean Society of London (Botany). 1 (1857): 130–140.

12. Futuyma, Douglas J. Evolution. 3rd ed. Sundbury, MA: Sinauer Associates, 2013. 

13. Dawkins, Richard. The Selfish Gene. New York: Oxford University Press, 2006.

JIMMY LIN: Currently I’m on faculty at Washington University at St. Louis, where I am a research instructor in the pathology department. Also, a year and a half ago, I founded the Rare Genomics Institute (RGI)—a nonprofit that helps find cures for people with rare diseases.

ER: What qualifies as a “rare disease”?

JL: These are diseases like cystic fibrosis and Huntingdon’s disease—diseases that affect less than 200,000 Americans each year. There are over 7000 different rare diseases, and less than 5% of them have any therapy. Altogether, they affect about 25-30 million people.

This creates what we call a “long tail problem”—it’s hard for a top-down research system to create research programs for all 7000 rare diseases. So instead, we are creating a bottom-up platform from which the patients themselves can create research projects and help fund them. We connect patients with physicians and researchers, customize a research program with top medical universities, design the experiment, and then use an online fundraising platform to fund the study through [mostly] friends and family of the patient.

Basically, we create a “foundation in a box.” By partnering with the Rare Genomics Institute, patients and their friends and families who want to study rare diseases don’t have to go through the hoops of creating their own nonprofit or lab—we do that for them. So, instead of creating 7000 different nonprofits, we create a generalized platform from which studies can be conducted.

ER: Who qualifies for care through the Rare Genomics Institute?

JL: Anyone with a rare disease can come to us. The main thing we’re doing right now is diagnosis. When families come to us, they either don’t know the disease that’s affecting them or their child, or they don’t know the gene that’s wrong.

For instance, if a child had a condition that doctors couldn’t identify, his or her parents might come to us for help. What we’d do then is sequence the genes of the mother, father, and child, and compare them to reference genome to determine what mutations each of the parents have. Depending on what the disease is and what the gene causing it is, we can filter out mutations that don’t mean anything using the parents’ genomes—then, after filtering, we can potentially pinpoint the genes that fit the genetic pattern of the disease. This is the first step.

After that, we are building infrastructure to determine the effect of these changes and a way to help. For example, after looking at the literature, we can perhaps design experiments using cells extracted from the patient; this part of the process is different for every disease. Then, if we can determine that there is, for instance, a pathway missing a specific enzyme, we can try using drugs, a bone marrow transplant, or gene therapy to try to put healthy cells into the child… But there’s a variety of diseases, of course, so there’s a variety of different approaches—and we’re just starting to explore these aspects.

ER: How did RGI get started?

JL: It really started when I was in medical school at Johns Hopkins—there was this boy that came to our clinic to be seen. My research was in cancer genome sequencing, and the family had come to our department looking for answers about what was wrong with their son. At that point, the family was almost hopeless—they had gone to so many doctors, run so many tests—I decided I wanted to try to help children like this. That’s when my friends and I decided to start the Rare Genomics Institute.

Currently, there are about 50 researchers associated with the organization, and we are all volunteers. It’s growing much, much faster and been more amazing than we’ve ever imagined—we’re already making an impact. In May of last year, we were able to discover a new disease using the world’s first crowd-sourced, crowd-funded genome. Working with researchers at Yale, we delineated a disease of which our patient was the first identified.

Right now, we’re in the middle of raising funding and hiring staff to make this organization one that is self-sustaining, and to increase its impact even more.

Excerpts from Michael Hickerson Interview

MH: …you call yourself a doxologist. What’s the full term you used in your Jubilee bio?

JL: Medical and scientific doxologist.

MH: How did you decide on that term and what does it mean to you?

JL: I listen to a bunch of teaching by J.I. Packer , who teaches theology at Regent College and is one of the leading thinkers on these things. Interestingly, before any one of his classes, he says “Theology is for doxology,” and then the whole class sings the Doxology together out loud in class. I thought, “Wow, that is so great,” because everybody sometimes learns theology just for intellectual things [instead of for worship].

That’s not just true for theology, it’s for everything: biology is for doxology; chemistry is for doxology. That’s when I started to think, I should consider myself, first and foremost, as a person who praises God in what I do. And then no longer make “Christian” the adjective, right? “Doxologist” is the noun. But then what kind of doxologist am I? So I call myself a medical and scientist doxologist. I would call someone, for example, in the marketplace, a business doxologist. Or, someone who does art, an artistic doxologist. To really have the noun as our identity, and then our vocation as just a descriptor of how we do that.

MH: That’s a great point. A noun is always stronger than the adjective. So, you want that to be the focus, rather than the add-on.

JL: In our current culture, we’re defined by our jobs. It’s having a vocation. I wanted to shift away from that. I didn’t want to be a doctor first and foremost, or a scientist, but one who praises God. And evidently, within science you don’t want to call yourself a Christian Scientist. That’s another religion, so . . .

MH: [laughs] That’s right. I run into that, as well, when I’m teaching or talking about science to Christians. You always run into that stumbling block.

JL: With “scientific doxologist,” people don’t confuse them. You do have to explain what it means. And that gets in a little story actually, on what it means about vocation. It’s a small lesson — a teaching point when you do talk to people about vocation and calling. That’s why I use it.

MH: I guess my final question would be what spiritual practices help sustain you? What helps you stay in contact with God and keep a good foundation?

JL: First, I am interested in many, many different things. I sort of mix it up in terms of spiritual practices. Besides the fundamentals, of course, of quiet time, devotional reading, and scriptural reading, I do theological study because I have to do that academically. I find a lot of time with God through the spiritual disciplines, such as times of solitude — which is very interesting for someone who is in academics to no longer think about ideas but just to be quiet before God — how silence, time to think by yourself, or sitting in silence is also something you should foster.

In terms of spiritual formation, what you really need is definitely a good community of people. I have a very supportive community at my church. I’m the deacon of devotions, so that of course keeps me on track. It encourages me as I, in my own spiritual walk, encourage other people. Fundamentally, I think for all Christians, whether you are academic or no matter your vocation or calling, being in the Word and prayer are the most important things. Doing that and being spiritually fed is what is important.

DOUG LAUFFENBURGER: It could look like a lot of things. One way to envision what I mean is to put yourself back a hundred years. For instance, in 1913, an electronic computer was unimaginable. But using physics, quantum physics, leading to semiconductors and devices like that, people figured out over the next 20 to 30 years how you could build a machine to do calculations and so forth. And then, of course, all sorts of thing happened…

We’re roughly at that stage with biology, even though it seems like things are more imaginable because—and we don’t have to go strictly century by century here—because we can already guess the way some things might change, whereas in 1913 there was no inkling, really, as to what would happen in the computer revolution.

So, to enumerate some of the things that are conceivable—let’s just start with computers, because we were just there.

There’s a notion that computers get faster and cheaper by making their logic gates smaller, and how you improve a design with physics keeps bumping up against how you make these little units smaller. Well, using biology, the solution seems self-evident—you just line up the pieces of DNA, and if you put the right pieces of DNA in the right places, the resulting parts are so much smaller than the things we can do with physics. You can imagine, even though it’s just a theory now, computers continuing to become many times smaller and cheaper—and be made via environmentally benign manufacturing processes—through biomolecular construction.

Now that’s exciting from one point of view, but from another, it’s not that revolutionary, because you’re just using DNA as a piece of physics. It’s not really biology—it’s merely a biological molecule being used to make better physics.

For a different example, if you think about the way we make things, the way we manufacture plastics, gasoline, energy—we have to do all that using chemistry, and to make that chemistry happen, we have to input a lot of energy—in fact, one of the most costly industries in terms of energy usage is the energy industry. You have to put in so much energy to refine petroleum and things like that. And to make plastics, ceramics—things of that nature—is also very energy intensive, and it’s also where a lot of pollution comes from, because you’re mixing together all these chemicals that really didn’t want to be mixed together. You get what you want, but you get a lot of byproducts, toxins, etc.

Well, people have started to realize that a lot of this work can be redone through the use of biology. You can turn corn into fuel or plastic, and you can make magnetic or electrical storage devices out of biological units (viruses can pattern the crystals, so instead of using mixtures of toxic chemicals, you just pull the viruses with the right properties together). Right on this tabletop, you could make materials that by current manufacturing processes would otherwise cause a great amount of environmental hazard.

As for another exciting development—well, to preface, one of the problematic things about modern agriculture is the necessity of using fertilizers (there are insecticides to be concerned about, too), but fertilizer manufacturing is terrible for the environment. You have to make fertilizer out of ammonia and that’s a horribly polluting and energy-intensive manufacturing process. What you could potentially do, instead, is program into bacteria the genes that take nitrogen out of air, turning it into organic nitrogen then just scatter the bacteria onto the field—and you wouldn’t need to make ammonium using the current very caustic processes.

These are the sorts of things I mean—and we haven’t even touched on medicine, yet. People tend to think about medicinal advances, first, but before you even get to medicine, you can think about energy, manufacturing, materials, and agriculture. In 50 years, we should be able to do things in ways we don’t do them now, that will be cheaper, less toxic, less polluting, more efficient, and so forth.

ER: A lot of people are nervous about the idea of “programming” life. Can you respond to this fear as a Christian?

DL: As a Christian, I would say that God gave humankind dominion over the earth, to do good things—he gave us minds, a passion for understanding how things work, and then he put in this world all these fascinating processes, which, if we figured them out, we could do good things, could feed more people—could feed more people without causing extensive damage to the environment. And cure disease and injury. And the list goes on. I think all that is good, and that God would be pleased that we would be using His creation to live better—I’m not saying more luxuriously, but more happily, contentedly, with each other.

ER: But back to the topic—advances using biology in the next century. You had just mentioned medicine…

DL: So, yes, there’s also medicine. Now, obviously, in thinking about this, the use of stem cells comes to immediately the fore. There are a lot of diseases out there that you really do need to correct using cellular processes. Right now, we try to make these corrections through chemistry. For instance, we give you a pill, and that pill should interfere with something that’s going wrong in your body—and yet it’s really never adequate to just interfere with something that goes wrong in the body, because you don’t really set it right just by getting in the way of it.

The opportunity with stem cells is that you can say, “I’ll replace the cells in the body that are doing something wrong with cells that are actually doing it right again.” If you program cells to be neurons, heart cells, or bone cells, you can regenerate properly functioning physiology. Rather than, say, replacing a hip with a metal part, you could regenerate the bone, itself, or you could regenerate neurons in Alzheimer’s patients. Never in the past has medicine been able to regenerate a proper physiology; it’s only tried to replace it with an inadequate surrogate, or minimize how much damage a disease is doing. With the use of stem cells, you can actually imagine returning the body to its proper physiology.

A different use of stem cells is to generate human tissue in the laboratory for better studies of human physiology and pathology and improved testing of drug effectiveness and toxicity.  This will be a major advance over animal models, because of the significant disparities between animal physiology and human physiology.

A key point to emphasize is that there are different kinds of stem cells, which involve big differences in potential concerns. For Christians, clearly, stem cells derived from embryos present a tremendous ethical issue. Fortunately, a good proportion of stem cell technologies can be pursued using stem cells from adult tissue. These cells can be stimulated to develop into certain tissue-specific physiological behavior, or can now even be “re-programmed” to become quite similar to the more broadly flexible stem cells derived from embryos but now not requiring the embryonic source. Happily, the days of reliance on embryo-derived stem cells appear to be over for purposes of beneficial technologies.

We also should consider genomic medicine, and what’s attractive about that field is that with the way we do medicine now, which is chemistry-based—say you have a disease, and we might give you a pill to correct it—well, the biggest problem with that is that while I think this pill will help ameliorate your condition, maybe it won’t. Maybe that drug only works in ten percent of the patients and not ninety percent.

For example, consider cancer. You’ve got a particular kind of cancer, and we prescribe a certain treatment… well, hopefully you’re among the lucky ten percent, and you’ll be in much better shape in two or three years. If you’re not, then we’ve wasted your time. In fact, we’ve probably hurt you rather than helped you, because we’re using chemistry to interfere with things, and even though we might be reducing the damage of some things, we’re probably causing toxicity elsewhere in the system, because that same chemistry is also interfering over there.

So the value of genomic medicine is to get enough information about you through sequencing your genome that we can say, “Ah, for you this particular pill is not a good idea; it will actually do more damage than good. But for your brother, it’s likely to work, and the ratio of benefit to harm is much better.” This is the reason genomic medicine is more imminent—it’s what’s closest on the horizon to being realized—because we can use the same drugs we have now, we’ll just be using them more effectively. At the moment, we can sequence genomes, and we do have these treatments that help, and it’s just a matter of matching up these two technologies.

Now, on the other hand, when you think about genome sequencing, you can find out all sorts of things, and you have to decide, “What if I learn something negative?”

EDITOR’S NOTE: Join us next week as we continue the conversation about genomic medicine, bioengineering, and being a Christian in science.

The tenth anniversary of the human genome has been marked by some striking new genetic insights into human evolution and diversity. Do these new discoveries have any significance for the dialogue between science and religion in general, or for our sense of human uniqueness in particular?

The publication of the Neanderthal genome sequence in May 2010 set the pace. Not surprisingly -- given that our last common ancestor with the chimpanzee was around 5 to 6 million years ago, compared to a mere half a million years for our last common ancestor with the Neanderthal -- it turns out that we are genetically far closer to the Neanderthals than to the apes. In all, only seventy-eight changes in the genetic letters ('nucleotides') that would change the amino acid sequence of particular proteins were found in the Neanderthal DNA that were the same as the chimpanzee sequence but different in the human. Amongst other differences, 111 duplications of small DNA segments were found in the Neanderthal but not human sequence. Genetically we are closely related twigs on the great evolutionary bush of life.

But we knew that already. More surprising for many was the provocative finding that non-African humans are genetically closer to Neanderthals than African humans. In fact, the European and Asian genomes that were sequenced appear to contain one to four percent DNA of Neanderthal origin, and the gene flow that occurred appears to have been almost entirely from Neanderthal to human, rather than vice versa. How come? The most likely scenario is that there were a few instances of sexual reproduction between Neanderthals and human individuals belonging to the population that is thought to have emigrated out of Africa to populate the world sometime after seventy thousand years ago, explaining why the Neanderthal DNA sequences are not found in African genomes. The contribution of the Neanderthal genome has remained in European and Asian populations ever since.

To put this in perspective, most of our genes are very similar anyway to those found in Neanderthals and chimpanzees, and to other mammals like mice. We all share a "how-to-build-a-mammal" instruction manual, and the relatively minor genetic differences between us (minor relative to those we share in common) are the icing on the cake, as it were, that make us a human rather than a mouse, a chimp or a Neanderthal.

The year 2010 saw yet another twig appear on the hominin branch of the evolutionary bush, this time one even closer to the Neanderthals than our own. This story begins with the discovery by a Russian team of a sliver of finger bone from a remote Siberian cave in the Altai Mountains, known as the Denisova Cave. The team stored it away, thinking it was from one of the Neanderthals that frequented the cave between thirty thousand and forty-eight thousand years ago. But when DNA extracted from the bone was eventually sequenced, the results -- published just before Christmas -- revealed a population distinct from both humans and Neanderthals.

The finger appears to belong to a novel hominin population that shared a last common ancestor with Neanderthals more recently than humans, and overall is genetically closer to Neanderthals than to humans. It is too early to say whether the so-called 'Denisovans' represent a separate species and fossil data will be required to clarify that question. But what the results do suggest is that Melanesians -- the inhabitants of Papua New Guinea and islands northeast of Australia -- have inherited as much as one-twentieth of their DNA from the 'Denisovans', indicating that some limited inter-breeding took place between these ancient populations. Most fascinating of all is the idea that multiple hominin lineages were coexisting in Europe and Asia, along with modern humans, as recently as twenty-thousand to forty-thousand years ago.

Do these findings have any particular theological significance? It is difficult to know why this should be the case. In the Judeo-Christian tradition humankind uniquely is made "in the image of God". The suite of capabilities that emerged during human evolution is necessary but not sufficient to do justice to this much discussed theological insight. Our particular genetic instruction manual generates large frontal lobes, advanced cognitive abilities, rationality, language, consciousness and the ability to choose between right and wrong. It is this suite that gives us the ability to pray, worship and engage in communal religious practices.

But the idea of being made "in the image of God" is not encompassed simply within a static list of such human qualities. Theologians have drawn attention to the dynamic, relational aspects of the concept. It is humanity-in-relation-to-God, together with God-given responsibilities to humans in relationship with each other, that are thought to be more central to the idea. When did such spiritual capabilities and responsibilities first come into being? It is really difficult to know, but the answer certainly seems more rooted in God's intentions and purposes for humankind than in genetic change per se. Students can spend a long time being trained in the finer points of drama, but the play only gets off the ground when the actors are finally given their lines.

It seems quite likely that more twigs will continue to appear on the hominin branch of the bush of life as genomics continues to extend its reach. Such discoveries as such do not appear to raise any new theological questions. But other 2010 discoveries did highlight two genomic insights that do have relevance for religious views of human identity. The first insight comes from further Genome Wide Association studies that continue to subvert any lingering commitments to genetic determinism, for example the idea that there are genes "for" a particular human trait. The second insight comes from the finding that we are all more genetically different from each other than we realized even a few years ago. Genetics is underlining the uniqueness of each human individual. By the end of 2011 it is estimated that more than 30,000 human genomes will have been sequenced. Watch this space. Theological reflections on these findings will be the topic for Part 2.

Behe and IC

Since we have previously explored Behe’s idea of irreducible complexity in an entire series, we will not revisit it here in great detail. It is important, however, to reemphasize how Behe defines irreducible complexity (IC). As we noted in the first part of that series, Behe frames his ideas on IC as a counter to Darwin’s ideas of gradualism.

For Behe, the argument for IC is a critique of gradual evolutionary processes, of the kind that Darwin saw as necessary for his theory to hold. When Behe introduces and defines IC in his book Darwin’s Black Box, he has a key quote from Darwin on gradualism explicitly in view:

Darwin knew that his theory of gradual evolution by natural selection carried a heavy burden: "If it could be demonstrated that any complex organ existed which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down."

It is safe to say the most of the scientific skepticism about Darwinism in the past century has centered on this requirement… critics of Darwin have suspected that his criterion of failure had been met. But how can we be confident? What type of biological system could not be formed by “numerous, successive, slight modifications”?

Well, for starters, a system that is irreducibly complex. By irreducibly complex I mean a single system composed of several well-matched, interacting parts that contribute to the basic function, wherein the removal of any one of the parts causes the system to effectively cease functioning. An irreducibly complex system cannot be produced directly (that is, by continuously improving the initial function, which continues to work by the same mechanism) by slight, successive modifications of a precursor system, because any precursor to an irreducibly complex system that is missing a part is by definition nonfunctional. An irreducibly complex biological system, if there is such a thing, would be a powerful challenge to Darwinian evolution.

(Darwin’s Black Box, p. 39)

The definition of an IC system is thus straightforward: it is a matched group of components, where all the components are necessary for the function of the system. The necessity of each component can be demonstrated by attempting to remove it – if the system no longer works if even one component is removed, it is by definition IC.

Behe and exaptation

The standard response to Behe’s argument from IC is to discuss the evolutionary concept of exaptation: that new systems and functions are cobbled together from components that have functional roles in other systems already present in the cell. Behe discusses, and ultimately dismisses this idea in Darwin’s Black Box as follows:

In Chapter 2 I noted that one couldn’t take specialized parts of other complex systems (such as the spring from a grandfather clock) and use them directly as specialized parts of a second irreducible system (like a mousetrap) unless the parts were first extensively modified. Analogous parts playing roles in other systems cannot relieve the irreducible complexity of a new system; the focus simply shifts from “making” the components to “modifying” them. In either case, there is no new function unless an intelligent agent guides the setup.

So for Behe, two points are clear: parts selected for function in one system cannot be exapted for use in other systems since they would require too many modifications; and the emergence of a new function is the indication that an intelligent agent is guiding the process.

Behe has responded to my previous posts to claim that the tandem duplication event that brought about the Cit+ actualization event should not be considered a gain-of-FCT mutation under his criteria:

The gene duplication which brought an oxygen-tolerant promoter near to the citT gene did not make any new functional element. Rather, it simply duplicated existing features. The two FCTs comprising the oxygen tolerant citrate transporter locus -- the promoter and the gene -- were functional before the duplication and functional after. I had written in my review that one type of mutation that could be categorized as a gain-of-FCT was gene duplication with subsequent sequence modification, to allow the gene to specialize in some task. Venema thinks the mutation observed by Lenski is such an event. He has overlooked the fact that there was no subsequent sequence modification; a segment of DNA simply tandemly duplicated, bringing together two pre-existing FCTs.

As an aside, quibbling over whether this mutation constitutes a “genuine gain-of-FCT” mutation is not my purpose here, since the definition is Behe’s to define, and I am not aware of anyone else in the scientific literature who uses Behe’s definitions. That said, I consider it passing strange to claim that a series of events that produced a gene that has a new sequence and functional properties distinct from either of its component parts does not constitute the production of a new “functional coded element.” If nothing else, it is a functional coded element that has not previously existed, cobbled together from parts of other functional coded elements, displaying new, adaptive properties. If according to Behe’s definition that’s not “new” or a “gain” then I guess it’s not, but that seems to me to torture the words “new” and “gain” beyond recognition. But I digress.

The important point for our purposes, however, lies elsewhere. Note carefully how Behe describes the Cit+ actualization event. By dividing the new aerobic citrate transporter gene into two previously existing FCTs, Behe is describing an exaptation event. The one FCT (the aerobic promoter) starts off as a necessary component of a gene transcribed when oxygen is present. As such it is under selection for that function, which has nothing to do with expressing a citrate transporter. The second FCT (the citrate transporter amino acid coding sequence) is under selection to be a citrate transporter, which has nothing to do with the function of the gene the promoter comes from. The Cit+ actualization event, then, exapts these two FCTs by placing them together to create a new function (which Behe does not mention).

And here’s the kicker: the new system (expression of the citrate transporter when oxygen is present) requires both FCTs in order to work. It has become a system of “well matched, interacting parts that contribute to the basic function” (i.e. transporting citrate in the presence of oxygen) “wherein the removal of any one of the parts causes the system to effectively cease functioning.”

In other words, it is a new IC system – a small and relatively simple system, yes, but nonetheless IC. Now, I’m fairly sure that Behe would not define this system as IC, since the documentation of an IC system evolving would seriously undermine his thesis. I am interested, however, in how he will handle this development, on two fronts. First, he would need to explain specifically why two exapted FCTs that are required together for a basic function does not constitute an IC system (if indeed he wishes to preserve his definition). Secondly, given that he allows for exaptation in this case, he needs to explain how exaptation is not a threat to IC in general. In Darwin’s Black Box he disallows exaptation altogether, but that option is no longer on the table.

In the next post in this series, we’ll continue to explore the evidence for exaptation as a means to build new FCTs, and go on to examine the implications of this evidence for Douglas Axe’s proposed limit to evolutionary mechanisms.

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, Darwin’s Black Box: The Search for the Limits of Darwinism (New York: Free Press, 2006).

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.

With the complete genome sequence in hand, we knew the sequence and location of our genes, but what we didn’t know was how all those genes are regulated: how do the trillions of cells in our bodies know when to turn on or off all those genes? How do the hundreds of distinct cell types develop and function together, when they are all running on the same DNA “operating system?”

That’s where the ENCODE (short for Encyclopedia of DNA Elements) project comes in. Launched in September 2003, shortly after the announced completion of the Human Genome Project, the goal of the ENCODE project is “to build a comprehensive parts list of functional elements in the human genome, including elements that act at the protein and RNA levels, and regulatory elements that control cells and circumstances in which a gene is active.” In other words, the project seeks to understand how the genome “works.”

Early this month, researchers from ENCODE released more than thirty papers presenting their findings. During a Science magazine online chat, the project’s data coordinator, Ewan Birney, explained the outcome:

The ENCODE project aimed to start our understanding of how the human genome works. We know that (nearly) all the information that determines a human is in the genome, as we all start off as single cell with this DNA. However, we had a patchy understanding of how it works, in particular away from protein coding genes.

To work out how the genome works, we used the fact there are many tiny machines (proteins and RNA - RNA is very like DNA) in each of our cells which know how to "read" parts of the genome. By monitoring where these little molecular machines are on the genome, or how parts of the DNA are copied into RNA (there are quite a few different types of RNA as well), we start to gain some insight into the genome.

We did many such experiments, across different cell types (eg, one cell type was very similar to a liver cell type; another was very similar to a white blood cell). This way not only can we see what is similar, we can also see differences between these cell types.

There is a lot more to get to know and understand here - this is definitely closer to the start than the end. But it is a substantial amount of data, and analysis, to start on this journey.

According to the abstract of one of the lead papers from Nature, this extraordinary glut of data “enabled us to assign biochemical functions for 80% of the genome, in particular outside of the well-studied protein-coding regions.” Only 2% of the genome codes for proteins, but 80% or more has some biochemical function. As a Science news article put it, these 30 papers “sound the death knell for the idea that our DNA is mostly littered with useless bases.”

The pro-Intelligent Design organization The Discovery Institute has heralded the discovery as the “demise of junk DNA.” Casey Luskin writes for their blog Evolution News:

Let's simply observe that it provides a stunning vindication of the prediction of intelligent design that the genome will turn out to have mass functionality for so-called "junk" DNA. ENCODE researchers use words like "surprising" or "unprecedented." They talk about of how "human DNA is a lot more active than we expected." But under an intelligent design paradigm, none of this is surprising. In fact, it is exactly what ID predicted.

The extent to which the ENCODE project been able to identify function has been surprising—even exhilarating—though scientists have for some time been getting glimpses of the many ways in which segments of DNA can be “active.” Even in 1970 biologists knew that some non-coding DNA had function, and by 2003 there was a large body of work demonstrating that many non-coding elements acted as promoters, enhancers, insulators, and so on. Indeed, in recent years many have come to appreciate the fact that “junk” was never really an appropriate metaphor in the first place. Still, because sequencing of multiple genomes has shed such extraordinary light on key evolutionary mechanisms, many geneticists have focused on function primarily in terms of which regions do or do not contribute to the evolutionary fitness of their host, rather than whether they were merely "doing something" biochemically. What the impressive ENCODE project has done is open a treasure trove of new information that can only accelerate the pace at which researchers are able to explore the incredible subtlety and complexity of DNA, and refine the very concept of “functionality.”

So with all this in mind, is ENCODE a stunning victory for ID, as Luskin believes? Bryan College biologist Todd Wood thinks not. He writes, “I don't think that function equates to design, nor do I think that design requires or predicts function. They're not the same thing… my understanding of function does not require me to hypothesize God (or an anonymous designer, if you must) as the proximal cause.”

We agree. Indeed we would go on to say that evolution and design are not mutually exclusive. So while finding function is not sufficient to prove design, recognizing that function has arisen by way of evolution does not indicate that God was not at work. We at BioLogos believe God providentially works out his purposes—his designs—through the elegant processes of evolution, not in opposition to them.

Amazing as the new data are, it only strengthens and enhances our evidence for evolution. While much of the genome is “doing something” biochemically, it is still likely that the majority of the sequence is evolutionarily neutral (Senior Fellow Dennis Venema discusses the evidence for this “neutrality” in a post on our site, including a striking comparison between 29 different mammal genomes and the human genome). In fact, another ENCODE researcher participating in the Science magazine chat, John A. Stamatoyannopoulos of the University of Washington School of Medicine, thinks the findings align beautifully with evolutionary theory:

ENCODE's data provide a unique and powerful window through which to view evolutionary change. We can see those changes directly by lining up the genome sequences of many different organisms -- these line-ups have revealed millions of regions where all the genomes agree, indicating sequences that have been specially preserved by evolution while others have decayed away (ie freely changed their letter codes). We now see that a large proportion of these 'conserved' regions are lighted up by ENCODE annotations, indicating that they are marking spots in the genome that contain important instructions for cell function.

We’ve discussed “junk” DNA previously, including a multi-part series by Dennis Venema, and we’ve received many emails over the past few days asking for our comments on the ENCODE findings. On Monday and Tuesday, Dr. Venema will begin to offer his own thoughts on ENCODE.

A special thanks goes to Darrel Falk, Mark Sprinkle, Kathryn Applegate, Dennis Venema, and Tom Burnett for their contributions to this post.

The Denisovans, an extinct hominid group that interbred with modern humans, made the news again lately with the publication of a more detailed study of their genome. One of the many interesting findings was that the Denisovans share the same chromosome 2 fusion that modern humans have. In this post, I review what we know about the origins of human chromosome 2, and then discuss the new Denisovan findings and their implications.

The origins of human chromosome 2: a brief review

Though I have discussed the evidence for a fusion event leading to human chromosome 2 before, perhaps a brief review of the evidence is in order. The human genome is made up of 23 pairs of chromosomes (for a total of 46 chromosomes). This makes us something of an oddity among living great apes, all the rest of whom have 24 pairs of chromosomes (for a total of 48). Given that there are many independent lines of evidence that support the conclusion that we share a common ancestor with other great apes, this poses something of a conundrum: how is it that our species arrived at this specific chromosome number? If we were to represent this “problem” on a phylogeny, or tree of relatedness, it would look something like this (not to scale):

Our closest living relatives, chimpanzees and bonobos, both have 48 chromosomes, as do all other great apes such as gorillas and orangutans. This pattern has one of two explanations, one of which is much more likely than the other. Either the common ancestor to these species had 48 chromosomes, and there was an event that reduced that number to 46 specifically on the lineage leading to humans (option A), or the common ancestor species had 46 chromosomes, and there were independent, repeated events that increased chromosome number in all other great ape species (option B). We can compare these options by placing the required event(s) on the phylogeny (again, not to scale):

It should be obvious that the option that requires the fewest events is the more likely one – in this case option A with an event that reduces chromosome number in the lineage leading to humans. The other option, that of repeated, independent events to increase chromosome number, remains a formal, but unlikely, possibility. Events that reduce chromosome number are not frequent occurrences, so Option A is more likely than Option B.

We can also find further support for Option A, because it predicts a specific type of event, namely one that reduces chromosome number. Since loss of a large amount of chromosomal material is almost always detrimental, we need an event that reduces chromosome number without losing information. One way for this to happen is for two chromosomes to fuse together and become one. Initially, this event would produce an individual with 47 chromosomes, where two different chromosomes get stuck together. Contrary to what is often assumed, this individual would be fertile and able to interbreed with the others in his or her population (who continue to have 48 chromosomes). In a small population, over time, two relatives who both have one copy of the fusion chromosome may mate and produce some progeny with two copies of the fused chromosome, or the first individuals with 46 chromosomes. Since either a 48-pair set or a 46-pair set is preferable for ease of cell division, this population will either eventually get rid of the fusion variant (the most likely outcome), or by chance will switch over completely to the “new” form, with everyone bearing 46 chromosome pairs. While not overly likely, this type of event is not especially rare in mammals, and we have observed this sort of thing happening within recorded human history in other species. Some mammalian species even maintain distinct populations in the wild with differing chromosome numbers due to fusions, and these populations retain the ability to interbreed.

Further evidence for a fusion event in the lineage leading to modern humans comes from comparing synteny, or gene locations and orders on chromosomes within modern great apes – an issue we have discussed here before. In brief, what we see in human chromosome 2 is exactly what we would predict for a fusion event. When compared to other great apes, we see the genes on human chromosome 2 match up, in order, with two smaller ape chromosomes. We also see that sequences used at the tips of chromosomes are present at the proposed fusion site, and that human chromosome 2 has not one but two sites for the cell cytoskeleton to attach to for cell division – but that one of the sites is mutated and not functional, though it lines up precisely with the location of this site on the appropriate ape chromosome. Together, this evidence consistently supports both common ancestry for humans and great apes, and specifically that the difference we see in our chromosome numbers arose due to a single fusion event. I briefly discussed this evidence in my last post where I describe how I teach some of this material and the compelling impact it has on students exploring the evolution question for the first time.

Enter the Denisovans

With that as background, we are now prepared to appreciate a new finding that comes from genomics work done on the Denisovan hominids, an archaic species that is more closely related to Neanderthals than to us, but that nonetheless interbred with some anatomically modern humans as they migrated out of Africa and populated the globe. (For those not familiar with the Denisovans, or the evidence for our interbreeding with them, both Darrel Falk and I have written on this previously, here and here). Recently, a more detailed understanding of the Denisovan genome was published, and nested in the new information is the discovery that the Denisovans share the 46 chromosome set with the same fusion that we have. This strongly supports the hypothesis that the fusion event predates the separation of our species. If we were to represent this on a phylogeny, we can now place this event with more accuracy than before (as before, the phylogeny is not to scale):

Despite this new information, one obvious question remains. Did the Neanderthals also have the 46-pair set? From looking at the phylogeny above, we can see that the most likely answer is that they did, since the fact that the Denisovans had it strongly implies that the last common ancestor of humans and Neanderthals / Denisovans had it as well, and the Neanderthal-Denisovan split comes later. While the Denisovan DNA samples are of high enough quality to make this assessment, we do not yet have Neanderthal DNA of high enough quality to do the same analysis with current methods (though one additional feature of the new work on the Denisovan genome is developing more sensitive DNA sequencing techniques that may resolve this question in the future).

In other words, this fusion seems to be an ancient one, predating our species by several hundred thousand years. Present estimates of the last common ancestor between humans and Neanderthals / Denisovans range at about 800,000 years ago.

Implications for understanding our “becoming human”

The main implication from this work is that it places the fusion event well before the advent of our species. I’ve often chatted informally with Christians about evolution, and at times some have thought that this fusion event was what “started” our species, or made our species unable to interbreed with other groups. Some have even suggested that perhaps the fusion event was what produced the first human (i.e. Adam).

Note that thinking this way suggests a misunderstanding of how chromosome fusions occur and what effect they have on their hosts. A fusion does not precipitate a speciation event, but rather the individual with the fusion remains a part of his or her population, and able to interbreed, even if with reduced fertility. Also, there is no necessary biological effect or change that the fusion produces on the appearance of the organism. These misunderstandings aside, however,what this new evidence shows is that this fusion event took place long before modern humans arose at around 200,000 years ago. Indeed, the 800,000 years ago date for the last human - Denisovan common ancestor means that this is the most recent date possible for the fusion. While it is an interesting piece of our evolutionary history, it doesn’t seem to have much to do with how we came to acquire the traits that set us apart from, and ultimately outcompete, other similar species.

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 Part 1 of this essay I pointed out that metaphysical naturalism is not necessary nor inextricably tied to the practice of science, and that essentialism is only one of the historically-Christian ways to think about being human. As a case in point, we can identify the Patristic Fathers and Medieval Christian thinkers who discussed a relational alternative for understanding the nature or being of persons.¹ Roughly, the idea is that the three persons of the Trinity are what they are and who they are in virtue of their relationship with each other, not based on some intrinsic properties that ground their uniqueness as persons in the Godhead. That is to say that Father, Son and Spirit co-constitute each other, or are bound up together with enabling each other to be distinctly the persons that they are. Far from a static form of being and relationship, there is a dynamic interrelatedness in the Trinity. Father, Son and Spirit mutually constitute each other while enabling each other to be particularly who they are and engage creation and salvation in particular ways suited to who they are as persons. Father, Son and Spirit are being in community.

By analogy of relationship, humans are what we distinctly are in our being and personality in virtue of our relationship to God, creation and each other. Our involvements with others necessarily shape who we are as particular persons. The personal realm, then, is characterized by a dynamic relationality, as persons have ongoing mutually constituting influence on each other. This is part of the “dynamic order” of creation “that is summoned into being and directed towards its perfection by the free creativity of Father, Son and Holy Spirit. That orientation of being is, of course, distorted and delayed by sin and evil, and returns to its directedness only through the incarnation and the redeeming agency of the Spirit. But evil distorts the dynamic of being, does not take it away.”² Like the relationality of the persons of the Trinity, we are being in community.

We can also pursue the doctrine of creation as an alternative to essentialism, to see if it sheds any light on possibilities for what it means to be human in a non-reductionist sense.³ As other writers have been exploring in the Forum over the past few weeks, the biblical claim that humans are created in the image of God is important to the Christian of view of humankind. This may sound like jumping out of the frying pan into the fire, for there are both Christians and non-Christians who claim that if humans arose through evolutionary processes, then we cannot be made in God’s image. Nevertheless, it is worth exploring as a way of showing that there are strong alternatives to a strictly essentialist understanding of being human.

The Image of God

Over the centuries, the dominant view of humans as the imago Dei has been grounded in the idea that there is something distinctive about the creation of humans that both sets us apart from the rest of the animals and that marks us as unique kinds of creatures. Though we are clearly both distinctive and unique, does affirming the imago Dei require this kind of essentialism? On the one hand, Genesis 1:27 has often been interpreted as grounding humanity’s being in the divine image of God on Earth. On the other hand, recent discussions in human evolution have focused on several independent lines of evidence supporting the hypothesis of common ancestry among primates and humans: fossil evidence over the last 6 million years; homologies or anatomical similarities between humans and the primates; biogeographical distribution of supposed human ancestors; similarities in developmental biology between humans and primates; and several lines of genetic evidence favoring common ancestry. In addition, our current best understanding of the genetic diversity of humans is inconsistent with models that assume all humans descended from a single original pair of individuals. Instead, the current best data and models indicate the human ancestral population was never smaller than several thousand individuals.⁴

On the surface, then, what contemporary evolutionary science currently says on human origins appears to challenge cherished beliefs and understandings of many Christians. However, to understand what implications, if any, an evolutionary development of humans might have on the image of God, we first need to get clear on what it means to be the imago Dei, and that has to be settled theologically, not scientifically.

Historically, some of the most popular proposals for the imago Dei were rooted in human rationality, human freedom or human creativity because it was thought that humans alone among the animals possessed one or more of these qualities. There are two problems with this traditional line of thought. First, investigations since the early 18th century have progressively led to the conclusion that such qualities of humans mark a difference in degree rather than a difference in kind (e.g., brains of mammals and humans are anatomically homologous, dolphins, primates, and some species of birds exhibit degrees of rationality and creativity). The degree of difference may be significant, but a difference in kind is necessary for the traditional line of essentialist thought.

Second, if we look to the Incarnation for clues to the imago Dei we find that Jesus’s humanity is never depicted as exercising extraordinary powers of rationality, freedom, creativity, and so forth. Primarily, Jesus lived as an embodied person in relationship with the Father, other humans and creation as enabled by the work of the Holy Spirit. In other words, Jesus’ human life in Scripture indicates that the divine image is a special relationship, or form of relationality: to be in relationship with the Father as a created, embodied person; to be sustained or upheld in this relationship with the Father through the perfecting Spirit; and to be in relationship with other persons and all of creation.⁵ Moreover, this special relationship is also a vocation to mirror or reflect the glory, life and worship of God.⁶

If to be the image of God is to be sustained in a special relationship with the Father, each other and creation through the Spirit, then the imago Dei is not grounded in intrinsic qualities that particularly mark humans as distinct from the rest of the animals, as essentialism would have it. Christians can understand Genesis 1: 24-31 and 2: 4-5, as many of the Patristic Fathers did, as an account of our unity and connection with the rest of creation as well as of our special relationship with God and role in God’s kingdom. So if Father, Son and Spirit created human beings through evolutionary processes, we would have continuity and connection with all of creation while still being the imago Dei. Evolution does not threaten human specialness before God unless it is viewed as a replacement for divine creative activity (which, of course, is what Richard Dawkins, Jerry Coyne and Answers in Genesis all do repeatedly).

If evolution is broadly right as an account of the creation of all living things (an empirical matter), and if some form of essentialism is found to be consistent with such an account (a philosophical and biological matter), Christians would then have two options for how to understand what it means to be human. We can look for some stable, unique intrinsic features in virtue of which we are human; or we can look to the special Spirit-sustained relationship we have with God, creation and each other. Both are biblically consistent, though I judge understanding the imago Dei as special relationship to make better sense of the whole of the Bible, as well as our experience in the world.

Notes

1. See Gunton, The one, the three and the many and Gunton, The Promise of Trinitarian Theology, T&T Clark (2003).
2. Gunton, The one, the three, and the many, p. 166.
3. Gunton, The Triune Creation; Robert C. Bishop, “Recovering the Doctrine of Creation: A Theological View of Science,” 31 January 2011.
4. For example, see Dennis R. Venema,“Genesis and the Genome: Genomics Evidence for Human-Ape Common Ancestry and Ancestral Hominid Population Sizes,” Perspectives on Science and Christian Faith, vol. 62, No. 3 (2010): 166-178.
5. See Gunton, The three, the one, and the many.
6. As such, the imago Dei has an inextricable missionary focus towards extending the kingdom. See N. T. Wright, How God Became King: The Forgotten Story of the Gospels, HarperOne (2012).

In a Nutshell

The meaning of the “image of God” has been debated for centuries in the church. A common view is that the image of God refers to the human abilities that separate us from the animals. However, scientists have found that abilities like communication and rationality are also present in animals on a basic level. Plus, theologians do not see the image of God as human abilities. Some theologians see the image of God as our capacity for a relationship with God. Other theologians see it as our commission to represent God’s kingdom on earth. Both of these theological positions are consistent with scientific evidence. Whether God created humanity through a miracle or through evolution, God gave us our spiritual capacities and calls us to bear his image.

In Detail

The “image of God” is a key concept in Christian theology, foundational to Christian thinking about human identity, human significance, bioethics, and other topics. Many Christians see evolution as incompatible with the image of God. How could God’s image bearers have evolved from simpler life forms? Doesn’t image-bearing require miraculous creation of humans rather than shared ancestry with chimpanzees? And when in the evolutionary process did humans attain this image? These questions are tied to many other issues concerning human origins, including the soul, the Fall, and the historicity of Adam and Eve (see sidebars), but in this article we will focus specifically on the image of God.

See “How does the Fall fit with evolutionary history?” and “Were Adam and Eve historical figures?”

The phrase “image of God” does not appear many times in the Bible, but the importance of the concept is emphasized by its repetition in the creation account:

Then God said, “Let us make mankind in our image, in our likeness, so that they may rule over the fish in the sea and the birds in the sky, over the livestock and all the wild animals, and over all the creatures that move along the ground.” So God created mankind in his own image, in the image of God he created them; male and female he created them. -- Genesis 1:26-27

From this text, it is clear that part of bearing God’s image is ruling over the animals. Genesis 9:5-6 reveals another aspect of image bearing: all human lifeblood is sacred because all humans are made in the image of God. The emphasis on Judeo-Christian thought on the sanctity of human life is derived in part from this passage. In the New Testament, the idea is expanded further as Christ is revealed as the true image of the invisible God (2 Corinthians 4:4, Colossians 1:15).

For centuries, theologians have discussed these and other passages, debating the meaning of the image of God (“imago Dei” in Latin). Being made in God’s likeness is not a matter of our physical appearance, because humans don’t all look the same. But to what does the image of God actually refer? Many ideas have been suggested over the centuries, producing a huge body of theological writing. While hard to summarize, we give a brief overview below of three common themes for the image of God. After developing this theological context, we’ll consider how these ideas intersect with evolution.

Image of God as our abilities

A common view is that the image of God refers to human abilities. When people talk of the things “that make us human,” they refer to abilities like reason and rationality, mathematics and language, laughter and emotions, caring and empathy, and cultural products like music and art. Often the motive is to distinguish humans from animals by showing that humans have unique abilities that make us special and superior to animals. Saint Augustine (354-430 A.D.) wrote something like this when he said “Man's excellence consists in the fact that God made him to His own image by giving him an intellectual soul, which raises him above the beasts of the field.”¹ Saint Thomas Aquinas (1225-1274 AD) also emphasized intellect and rationality in his discussion of image bearing.² But Augustine and Aquinas were not speaking of intellect as an aptitude for math or music; Aquinas instead writes of an “aptitude for understanding and loving God.” In fact, the modern emphasis on reason comes more from secular Enlightenment ideas than from Christian theology. During the Enlightenment, the image of God was connected to ideas like the natural dignity and majesty of humankind that separates us from the brute beasts of the animal world.

Scientific evidence is piling up that humans have more in common with animals than was once thought. Genetic evidence shows that humans and chimpanzees share much of their DNA. Studies of animal behavior (particularly of chimps and other apes) show that animals not only laugh and cry and care for each other, but can learn sign language and even have basic reasoning ability. In fact, Christian neuroscientist Malcolm Jeeves writes that “any attempt to set down a clear demarcation between the reasoning abilities of nonhuman primates and humans is found to have become blurred.”³ Obviously, humans have a much larger capacity to reason than animals, but reasoning is not a uniquely human ability. As neuroscientists and animal behaviorists learn more about animals, they see how traits appear in a rudimentary form at a level similar to human children.⁴ Whether or not one accepts evolution, evidence from living humans and animals does not show a distinct difference in kinds of abilities (only degree).

See “Made in the Image of God: The Theological Implications of Genomics” a 2-part blog by Denis Alexander.

Another challenge for this picture of the image of God is the place of people with mental disabilities. If a person is impaired in reasoning or language, are they bearing less of God’s image? Are they not showing his true likeness? The Christian answer to these questions is No! The Bible repeatedly teaches that God values all people, particularly those who are rejected by society or unable to care for themselves.⁵ In fact, Genesis 9:5-6 points to image bearing as the reason that all human life is valuable. This is a major motivator for Christians who seek to protect the unborn, the poor, and the aged. Surely bearing God’s image must mean something other than using our abilities.

PLEASE READ THE REST OF THE ANSWER HERE.

Notes

1. Saint Augustine The literal meaning of Genesis, Book 6, Chapter 12 (Google books, p. 193)
2. Thomas Aquinas, Summa Theologica, First Part, Question 93 (html)
3. Malcolm Jeeves, “Neuroscience, Evolutionary Psychology, and the Image of God” Perspectives on Science and Christian Faith (2005) 57.3, p. 178 (PDF)
4. Similarly, many human traits have been replicated in artificial intelligence, particularly logic and math but also conversational language and computer-generated art.
5. For more see, Kathy McReynolds “More Than Skin Deep” BioLogos Forum June 2010

As we’ve seen in recent essays (and comments) touching on Biblical scholarship, philosophy, theology, and anthropology, the imago Dei is a complicated idea, linked to the question of whether what makes humans unique among the creatures on earth is physical, cultural, spiritual, or some combination of all three. As Christians who seek to frame what the natural sciences tell us about our physical humanity with what the Bible suggests are our defining human qualities, we tend to focus on what Genesis means when it says Adam was “made in the likeness of God”; but it is helpful to remember that the first mention of God’s image in human form looked forward to the full revelation that would come in Christ. Thus, we ought also seek to understand Jesus as the model towards which Adam always pointed, and by which we should understand both Adam and ourselves.

Going one step further, we should also look forward from Jesus to the life of the Church. For if Jesus was the true image of God, then at Pentecost, the new community of believers took on the role of imaging the continuing presence of God in and for the world. The Church was constituted as the very Body of Christ, charged with making him known in their lives as well as their words. Thus in the structure and life of the Church we also see something important about the imago Dei.

Perhaps one way to hold in tension the various interpretations of the image—that is, to affirm the incomplete truths available through the relational, functional, substantial, and elective models—is to look at a literal image of the way the social aspect of imaging God via the Church interacts with the intensely individual and personal aspect of imaging God in individuals. Picking up on Kathy McReyolds’ sketch of personal transformation through encounters with those with disabilities (More than Skin Deep), I’d like to turn our attention towards the work of Chicago artist Tim Lowly, whose monumental portrait of his disabled daughter (Temma on Earth, 1999), is pictured above. Lowly’s work compels us to recognize the image of God even in one who lacks markers of those other roles, capacities, and relationships, and highlights two linked characteristics common to Jesus and Church: brokenness that does not merely equate with imperfection, and a social picture of our essential identity in Christ. By allowing Lowly to place Temma’s identity and humanity at the center of our attention, we can reframe our sense of what it means to bear the image of God and reflect the crucified Christ as his Body.

Profoundly Other

Born in North Carolina but spending his youth in South Korea (where his parents were Presbyterian missionaries), Tim Lowly attended Calvin College and began work as an artist in Michigan. But his life and work took an unexpected turn in 1985, when Tim and his wife Sherrie’s daughter was born and suffered a medical emergency during her first two days home from the hospital. In 2002, journalist Fred Camper’s incredibly sensitive article treated the Lowlys’ physical, emotional and spiritual journey with Temma at length, and I encourage readers to turn to that essay for the full narrative background to Tim’s approach to his daughter and his art. But the central facts are that for all of her now 27 years, Temma’s host of physical and mental disabilities have made her completely dependent on others, and have meant that the relationship she has with her parents (and they with her) is a radical departure from ‘normal.’ Temma’s “profound otherness” challenges most of our expectations about the human capacity to image God. Speaking to Camper, Lowly describes Temma:

It's unlikely that she thinks in a way that we would call thinking," he says, "because our ways of thinking are based so much on learning, experience, sight, socialization, and history, and I doubt any of those things have any bearing on Temma. I don't even think comparing her to animals makes sense. There's a certain wholeness to the way animals think that I don't think Temma is capable of. I'm pretty sure she does have an inner life, but I don't think she has the mental mechanisms that would make it correspond in an understandable way to the way we think.

And yet Lowly has produced hundreds of paintings and other works that feature Temma, some of them monumental in scale, none of them shying away from questions of the purpose, value, and meaning of her life for their family, and for ever-widening circles of community. Certainly there is a political component to Lowly’s work that addresses inequity in culture and church. Generally, he says, the church has been compassionate, but “nearly always from perspective of the able-bodied and the ‘whole’ vs. the disabled, never mind that none of us measure up to complete wholeness.” Yet his work also reflects the way Temma, in her “otherness,” creates community. Artist-in-residence and gallery director at Northpark University since the mid-1990s, Lowly has often made Temma a physical presence in the studio and classroom. Carry Me, 2002 (drawing on panel, 108" x 48," at left) depicts students from an advanced class holding Temma, but they were also involved completing the project. Another large work, Culture of Adoration, 2008, shows Temma as the model in a drawing class, with Lowly drawing the parallel between that scene and the adoration of the Magi at Jesus’ birth. That comparison pictures the way a community forms around loving attention and worship, but subverts artistic and cultural expectations that only what is beautiful should be valued. Lowly notes that while Temma is often alone, in some ways she’s never alone: “She’s cared for by her parents, but that relationship extends out to a much broader church outside her family.” Both paintings, then, are images of Christ’s corporate body as much as they are of Temma or the painting students who carry and draw her.

What bearing, then, does Lowly’s particular way of seeing and depicting his daughter have on us, on our sense of the imago Dei? Part of his ongoing artistic project is to understand and interrogate the way the traditions of perspective in Western art and culture presuppose and privilege the individual, solitary and unified point of view as the most important, the most true. In the wake of modernist emphases on self-expression in art, Lowly also sees value in pursuing ways of working that bring out the meditative (and even prayerful) craft aspect of painting, and that at least partially de-emphasize his and other artists’ subjective positions. He increasingly works from photographs (and collages of many individual pictures), and has more and more sought to bring collaboration into the making of his work. When Lowly takes Temma as his subject, these features of his practice emphasize the way that, in the Church, our individual identity is experienced as a tension between brokenness and wholeness in the Body.

Broken Together

There is a sense in which we look at Temma and we want to affirm that she is made in the image of God by denying that the image of God has anything to do with her physical, material body. Indeed, one way to approach the problem made visible through Lowly’s painting is to imagine the soul as imparted to (or trapped in) the physical frame. This certainly fits with saying that the image-bearing role of humanity in general is an act of the grace of God, not something dependent on our abilities. But in the election model, we are reminded that God didn’t call Abraham just to a “spiritual” identity, but also to physically constitute a people sent into the very concrete physical world.

Likewise, if we recognize Jesus as our model for the image of God, we will not deny the physicality of the human experience, nor the incarnation, nor even Christ's suffering on our account. Indeed, we must affirm the goodness of creation and our physicality, even—especially—in its brokenness because Jesus, himself, was broken. Even after the resurrection, his wounds were not abolished or erased, but remained tangible marks by which the Lord revealed himself every bit as much as he did in his creative and healing power. And in the Revelation image of the victorious Christ, we have another picture of that essential and persistent sacrificial brokenness in the Lamb who appeared “as if slain.”

What of the Church? Similarly, the Church remains a fragmented whole when it is at its best—broken open to be dispersed into the world. And though it is also all-too-often broken by own individual and corporate sin, even that finds its meaning and redemption in the image of bread broken in the Lord’s Supper—the way that sharing brokenness together unites the individuals in a congregation with each other and with Christ. As a reminder of Jesus’ own individual body, communion addresses both of those senses; it is the means of both healing and sending.

Christ’s commission to the Church, then, presents a profoundly social model of being the continuing revelation of God for the world. We bear the image of God together, and the image of God is only fully realized when we are members of a community, in relation to other human beings (even if that relationship is one of complete dependence), as opposed to seeking independence. This does not and ought not compromise the absolute worth of each individual, but should remind us that part of our worth is tied up in our integration with the whole body of Christ.

One last example of Lowly’s work gives iconic form to this inter-relation between image-bearing, self, identity, and the community of the Church. Made to commemorate Temma’s 25th birthday in 2010, At 25(right, and below), is a collaborative piece constructed of 25 individual, two-sided panel blocks that fit together something like a puzzle. On one side is a black and white portrait of Temma, while on the reverse, the individual blocks have been painted and gilded in different patterns and techniques. Lowly constructed the piece, but sent each block out to be completed by 30 different artists, either working alone or in pairs. In requesting them to do their sections of the composite portrait in an “artistically neutral” style, he was asking them to subjugate their artistic personae and self-expression to the depiction of Temma. Not every artist was able to do that to the same extent, so the final object is an image of the imperfection of our self-giving—or our inability to see others without looking through our own particular lenses of self—even while being a testament to the compassion and care of Lowly’s dispersed community.

Most importantly for this discussion, At 25 suggests that our image-bearing of God does not rest on our individual “fitness,” much less how well we “fit in.” Rather, it is carried by the whole human community, most fully in the broken Body of Christ. In this respect, brokenness is not something to be corrected; it is something that makes the particular community of the Church possible. Individuals may not be able to fulfill or even recognize the functional aspects of the imago Dei, they may not even be capable of the relational aspects—or of returning expressions of love or kindness or thanks, or even awareness. But the whole body, the beloved community, the nation God set apart for himself and the world, is called to be the image of God for each of us—precisely when we can’t.

Tim Lowly is Assistant Professor of Art at Northpark University. An inter-disciplinary artist, he works with painting, drawing, installation, digital media, photography and music: both individually and collaboratively. His work has a lyrical realism and quiet spirituality that have contributed over the last thirty years to the development of a international reputation. While Tim’s art and music address a variety of subjects, the central pillar of his work has been his daughter Temma who is, in his words, “profoundly other”. The clinical diagnoses of “multiple impairment” or “spastic quadriplegia” do little to address the compelling presence of this young woman and the way her being and essence have shaped her father’s work.

Lowly was born in Hendersonville, North Carolina in 1958. The son of medical missionaries, he spent most of his youth in South Korea. He attended Calvin College and received a BFA degree in 1981. His wife Sherrie Lowly is a United Methodist Pastor. They reside in Chicago, Illinois. Since 1994 Tim has been affiliated with North Park University in Chicago as professor, gallery director, and artist-in-residence. Tim is represented by Koplin Del Rio Gallery in Los Angeles.

For additional information (including exhibitions and collections) see Tim’s personal website.

All images © Tim Lowly.

For the past twelve years, I have had the privilege to teach in the Bible Department at a prestigious Christian university. Most of my students have been raised in Christian homes and have attended conservative, Bible-believing churches all of their lives. These students believe that they have a pretty solid understanding of what the image of God entails; at least they think they do until they encounter the world of disability. Disability creates a dissonance in their worldview that they are not expecting. All of a sudden, what they thought they understood about the image of God comes crashing down like a house of cards. The image of God and disability just do not seem to go together.

The following quotes from some of my student’s papers are representative of many and their experience with the disabled “strange other.” What is communicated loud and clear is the challenges disabilities raise for their conception of the image of God:¹

I believe that those with disabilities are equal to us … but I discovered a hidden evil in my heart. Deep in my heart, hidden from the world, I believed that children born with disabilities that would normally not survive its first few days should be allowed to die.

I think I could have intellectually acknowledged that all men and women are created in the image of God … In this class I was challenged to see the realities of disability and ask if I really did believe that God created these individuals in his image and salvation was for them too.

Though I have always known that these individuals are created in His own image, I often found myself secretly thinking that they were miserable and often a burden on others.

Sometimes I feel pity for disabled individuals because they are not “normal”. I feel that their disability is hindering them from experiencing the best life possible. I think disabled people experience a lesser quality of life because they cannot physically and/or mentally do as many things as a “normal” person could.

Now, these young people are not more spiritually or morally bankrupt than others in contemporary society. In fact, to the contrary, these Christian students are considerably more spiritually and morally sensitive in general because of their commitment as Christ- followers. Still, these views have been nurtured and influenced by two factors, one that is cultural and one that is religious: 1) the pervasiveness of a reductionist view of human being fostered by scientism; 2) a wooden, literal interpretation of Genesis 2:7 which says that “the Lord God formed the man from the dust of the ground and breathed into his nostrils the breath of life and the man became a living being.”

Taken together, these two factors present a skewed view of human being, one that focuses on the physical and material rather than on the spiritual and essential. This is one of the reasons why my students twinge and recoil a bit at the thought that persons with disabilities can be made in God’s image. “They just don’t look like it,” they say, zeroing in on what is physically seen. This view has had enormous consequences for people with disabilities. In fact, Adolf Hitler, as part of developing his approach to the weaker members of society in his book Mein Kampf, identifies the stronger (better looking and functioning) members of society as “images of the Lord” in contrast to the weaker members who are mere “deformities” of that image, and who ought to be cleansed from society. Many have argued that Hitler’s ideas concerning those with disabilities were inspired solely by Darwinian evolution. However, these quotes from Mein Kampf reveal a horrific misuse of Scripture, not evolutionary ideas.

Furthermore, with regard to evolution, a face value exegesis of Genesis 1 & 2 does not dictate that the physical stuff God used to create human beings was special or unique or that the image itself resides in it. It shows, rather, that all matter was formless and void until God, who acted and willed out of his good pleasure and sovereign choice, brought order and harmony to it. This applies as well to the creation of human beings who are uniquely created in God’s image. If this image is not merely physical stuff, what is it? What does the literary and historical context of Genesis 1 & 2 reveal?

There are three views on the image of God: 1) Substantial; 2) Relational; and 3) Functional. The functional view sees the imago Dei as a function or role that humans fulfill--such as being priests or having dominion. The relational view has to do with humans imaging God in their ability to have spiritual relationships—primarily with God, but also expressed in terms of our male and femaleness and other nuances. The substantial view essentially says that God’s image is imprinted on the person’s soul as an image is impressed on a coin, and has much to do with human capacities like our free will and ability to reason. It has been predominant in Christian theology in the West since about 600 AD.

But though we do have specific capacities that bear on our responses to God, as the substantial view says, the human being is an embodied soul who has both relational and functional capacities, as well. The relational implications include the biblical truth that among all God’s creatures, only human beings can know Him and be consciously aware of Him. Most importantly, he knows us and can be in relationship with us even when we do not acknowledge him out of rebellion, or cannot respond to him because of disability. If we consider the Substantial view’s emphasis on conscious awareness, ability to exercise freedom, and decision-making capacities alone, however, some human beings may not qualify as persons, whereas some non-human animals might.

Against this, a more holistic view affirms that all human beings bear God’s image, regardless of capacities. The image of God cannot be lost or compromised in anyway. Even the poorest functioning human being profoundly reflects God’s image.

In an unexpected and peculiar way, my students discovered this truth about the image of God when they began to interact with people with disabilities in my classroom. This truth about the image utterly transformed and they began to see people with disabilities quite differently. The following quotes come from the same students quoted at the beginning:

What I came to realize is that since the disabled are people, they deserve life. As humans made in the image of God, we are to try to preserve our fellow disabled brothers and sisters who are also made in the image of God.

When I went to the day group home, it was an amazing experience. I really enjoyed interacting with everyone there. I was able to paint with them, and one of them sang to me and taught me to dance; it was so much fun. It was great to see how each and every one of them was so unique and made in the image of God.

In this class I was challenged to see the realities of disability and ask if I really did believe that God created these individuals in his image and salvation was for them, too. As a result of what I have learned from this class my answer to these two questions is a resounding yes! God loves individuals with disabilities and knows the depths of their hearts and minds on a level I could never comprehend. Who am I to doubt who God knows, who He loves, and to whom He offers the gift of His Son.

At the beginning of the semester, disability was a foreign world for me. That world was new and uncomfortable. I had no idea how to interact with anyone with a profound disability and had little desire to learn how. Throughout this course, the walls of misconceptions, fears, and insecurities that I have built up to distance myself from disability have slowly been chipped away. As I learned more about disability, my fears and discomfort were replaced with compassion and joy. Exposure to individuals and families with disabilities was the most effective way to break down those walls. Having the opportunity to observe and interact with individuals with disabilities was invaluable. Participating in disability ministry is not burdensome, as I had initially worried, but freeing. I left the night feeling uplifted, loved, and so aware of God’s mysterious presence within broken humanity.

During Jesus’ ministry on earth, often the best way to find him was to seek out those society considered strange, unclean, or undesirable; Jesus often sought them out, himself, in order to show that God’s love for us does not depend on our merits or abilities, much less our outward appearance. Similarly, my students today meet the Lord anew—and discover that same message of God’s unmerited grace and love—when they seek out relationships with those our society finds strange and broken, with those who they could easily avoid seeing at all. Rather than judging with the eyes alone, my students learn to recognize their cultural and theological blind-spots, and see both the disabled and themselves in the light of Christ’s love. Relationships are transforming; and relationships with people with disabilities can transform not only our image of them, but of the God who made in His image, and dwells with us in places deeper than the skin.

Notes

1. All student quotes used by permission. Names are left out to protect student privacy.

In the last post in this series, we introduced a paper by Chen and colleagues that sought to identify new genes in various Drosophila (fruit fly) species. The youngest (i.e. the most recently evolved) gene they found is one specific to Drosophila melanogaster, the species of fruit fly beloved by geneticists as a model organism. The gene is named “p24-2” (not the most imaginative name, but it serves its purpose) and the gene it is duplicated from is called “Éclair”. The Éclair gene is found in a number of Drosophila species. A simplified “family tree” of three Drosophila species (D. melanogaster, D. simulans and D. erecta) is shown below. The duplication event that generated the p24-2 gene happened within the lineage leading to D. melanogaster, but after D. melanogaster and D. simulans separated as distinct species:

Since the entire genomes of these species are now sequenced and available online, it is possible to look at the chromosome region where the Éclair gene is found in all three. By looking at this region in D. melanogaster, we see that the brand-new p24-2 gene is almost right next door to its “parent” gene, Éclair. Below is a screen shot taken when looking at this region using a Drosophila “genome browser” that is freely available online. The red arrow indicates the Éclair gene, and we can see p24-2 is just one gene over, and seems to be nested within another gene called “Unc-115b”. The green arrows are pointing to two different “versions” of how p24-2 is made into an mRNA working copy. The Unc-115b gene (blue arrow) has five different mRNA versions. (One of the p24-2 mRNA versions has a lot of Unc-115b sequence that is not used when the p24-2 protein is made).

(Click Image to Enlarge)

Finding a duplicated gene next door to the sequence it is copied from is pretty common in genomes – when chromosomes are copied or recombined during cell division, side-by-side copies of parts of chromosomes show up every now and then. It’s also not surprising to see a new gene cobbled together with another gene. In this case, Unc-115b and p24-2 are overlapping but separate functional entities: they each have their own protein sequences, but each includes the code of the other as a sequence that does not actually translate into protein. The details of how this “cobbling” happens aren’t important for this discussion, other than to note that the mechanisms are known and not rare. In the chart above, then, the orange sections indicate the active parts of the transcribed sequence, while the gray are sections that are included in the RNA molecule, but do not get used directly to code for the new protein.

When we look at this same chromosome region in D. simulans and D. erecta, however, p24-2 is missing. Éclair and Unc-115b are there, but p24-2 is not, since it arose after D. melanogaster separated from its common ancestors with the other species. (Note: this entire region is a mirror image in D. simulans and D. erecta when compared to D. melanogaster due to a large scale chromosome inversion that covers this whole area. So, while it looks “backwards” compared to the image above, that is not surprising, it’s expected):

(Click Image to Enlarge)

So, with the p24-2 gene in D. melanogaster, we have a bona-fide, recent gene duplication event. This gene is brand new, evolutionarily speaking (less than 3 million years old, given the calculated speciation times of D. melanogaster and D. simulans). Not only is it brand new, it is also essential for survival in D. melanogaster: if you remove it, the fly dies. Obviously, since every other Drosophila species lacks p24-2, this gene is not essential for survival for any other species. It’s new, and now it’s necessary.

Do new, essential genes refute the Intelligent Design (ID) argument from Irreducible Complexity (IC)?

So far, nothing we have discussed explicitly threatens the ID argument from IC, though it does threaten the ID argument that new information cannot arise through evolution, a topic we have discussed in detail before. Michael Behe, the main ID proponent of the argument from IC, has commented on this research by Chen and colleagues (thanks to commenter “Bilbo” for pointing this out). Behe’s rejoinder was to a blog post by biologist and atheist blogger Jerry Coyne, who used the paper by Chen and colleagues to attack Behe’s ideas. Since Behe’s reply deals with his understanding of how gene duplication relates to his argument from IC, I will quote it here at length:

I have never stated, nor do I think, that gene duplication and diversification cannot happen by Darwinian mechanisms, or that “they play almost no role at all” in the unfolding of life. (As a matter of fact, I discussed several examples of that in my 2007 book The Edge of Evolution. That would be silly — why would anyone with knowledge of basic biochemical mechanisms deny that, say, the two gamma-globin coding regions on human chromosome 11 resulted from the duplication of a single gamma-globin gene and then the alteration of a single codon? What I don’t think can happen is that duplication/ divergence by Darwinian mechanisms can build new, complex interactive molecular machines or pathways. Assuming (since he is in fact critiquing them) Professor Coyne has been attentive to my arguments, one background assumption that he may have left unexpressed is that he thinks the newer duplicated genes discovered by Professor Long’s excellent work represent such complex entities, or parts of them.

There is no reason to think so. A gene can duplicate and diversify without building a new machine or network, or even changing function much. The above example of the two gamma-globin genes shows that duplication does not necessarily result in change in function. The examples of delta- and epsilon-globin, which, like gamma-globin, presumably also resulted from the duplication of an ancestral beta-like globin gene, show that sequence can diversify further, but function remain very similar. Even myoglobin, which shares rather little sequence homology with the other globins, has not diverged much in biochemical function.

In his recent work Professor Long discovered that many of the new genes were essential for the viability of the organism — without the gene product, the fruitflies would die before maturity. Perhaps Professor Coyne thinks that that means the genes necessarily are parts of complex systems, or at least do something fundamentally new. Again, however, there is no reason to think so. The notion of “essential” genes is at best ambiguous. We know of examples of proteins that surely appear necessary, but whose genes are dispensable. The classic example is myoglobin. It is also easy to conceive of a simple route to an “essential” duplicate gene that does little new. Suppose, for example, that some gene was duplicated. Although the duplication caused the organism to express more of the protein than was optimum, subsequent mutations in the promoter or protein sequence of one or both of the copies decreased the total activity of the protein to pre-duplication levels. Now, however, if one of the copies is deleted, there is not enough residual protein activity for the organism to survive. The new copy is now “essential”, although it does nothing that the original did not do.

The main points of Behe’s reply can be summarized as follows:

1. Gene duplications and subsequent changes to the copies (diversification) can and do happen, but the results are nothing really “new”— no new molecular machines or pathways (nor parts of such pathways), nor much in the way of new functions.
2. Duplicated genes can become essential simply by “sharing” the original function, and then reducing their share to a minimum, perhaps through the amount of protein that each copy makes. Again, this is not anything really new, since the copy doesn’t do anything that the original didn’t do already. So, the finding that some gene copies are essential genes is not a threat to the IC argument.

Note that Behe’s reply makes predictions that can be tested with further research. These predictions might be summarized in this way:

1. If IC is correct, duplicated genes will not be part of new, complex molecular pathways or machines.
2. If IC is correct, duplicated genes that are both essential should “share” the original function.

Testing IC with new research

Behe’s reply to the Chen paper is of course hypothetical and speculative – as demonstrated by his own comment that “there is no reason to think” that the duplicated genes are components of new complex pathways or systems. Accordingly, the validity of Behe’s reply depends on its ability to hold up over time as more work is done. Of note, the functions of p24-2 and its parent gene Éclair have been studied intensively since 2010. These studies, as we shall see in the next post in this series, shed quite a bit of light on these questions.

For further reading:

Behe, M.J. Darwin’s Black Box: the Biochemical Challenge to Evolution. Free Press, New York, 1996.

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

Chen, S., Zhang, Y, and Long, M (2010). New genes in Drosophila quickly become essential. Science 330; 1682-1685.

Left: "Abrahamic Covenant" by Christoph Weigel, 1695.
Courtesy Pitts Theological Seminary, Emory University.

The people of your culture cling with fanatical tenacity to the specialness of man. They want desperately to perceive a vast gulf between man and the rest of creation. - Ishmael ¹

For the destiny of humans and the destiny of animals is the same: As one dies, so dies the other; Both have the same breath of life. And humans have no preeminence over the animals…All go to the same place; All come from dust, And to dust all shall return. - Ecclesiastes 3:19-20

What is humankind’s place among the animals? Should we even count human beings among the animals at all? Perhaps we—as men and women—are something else entirely? Such questions are not new. Indeed, they are as old as writing itself and similar ponderings about human identity occupy the most ancient of texts. While many of these primeval writings have crumbled in the winds of time and have come to us only in fragments, the Genesis account of human and animal origins remains a living document that occupies a vital place in the life of Christian practice and thought. In the first chapter of the Genesis narrative we read that humans—male and female—were created in the image (tselem) and likeness (demuth) of God. But what does this mean? There is certainly no shortage of proposed answers, and over two thousand years of theological tradition bears witness to this fact. Here, however, we are not primarily interested in tradition—as valuable and insightful as it may be—but we are concerned with what the Bible itself has to say.

Taking the authority of Scripture seriously demands that we engage with Scripture in light of both its original languages and its original cultural context. If we are to avoid—as much as it is possible—projecting our own personal, modern and post-modern cultural presuppositions onto Scripture, then we must be willing to do some of the hermeneutical (or interpretive) hard work. In other words, if we want to allow Scripture to speak for itself, we must be hyper-aware of the cultural lenses we are wearing when we read it. Interpreting the Bible through five hundred years of Protestant tradition, fifteen hundred years of Roman Catholic tradition, or one hundred years of Seventh-Day Adventist tradition won’t do.² Rather we must venture to take off the thick hermeneutical lenses of tradition and boldly attempt to go into the world of the sacred text itself so that we can allow the ancient inspired words to shape the lenses or our reading.

With this approach to Scripture in mind, I believe it is useful to address the matter of the image and likeness of God (or imago Dei) by first asking what the imago Dei is not. Throughout the centuries, theologians, philosophers, and others have posed a number of answers to the question of what the imago Dei is. The vast majority of these answers have focused on one or a few characteristics that humans alone have and that non-human animals lack. For example, Evangelical Christian author Kay Warren explains: “Animals and people are two different classes of created beings and they will never be equal in their worth. As precious as animals are to our daily existence, they operate from instinct, not volition. Only people have a spiritual dimension. We are the ones created in the image of the Creator, the only ones with a soul.”³ In a similar manner, political commentator Ann Coulter, citing “the story of Genesis”, maintains: “It’s not merely opposable thumbs and a bipedal gait that make us distinct from the other beasts. It is consciousness of our mortality, a moral sense, language, mathematics, art, beauty, music, love, longings for immortality, a sense of symmetry, the soul’s ascent, the ability to accessorize, and our fascination with Branson, Missouri…We are in God’s image, and we’re the only ones in God’s image, which is why we eat escargot rather than worship them.”⁴ While these are two popular contemporary voices, similar views are espoused by numerous academics as well. In this way the imago Dei has, for many, become synonymous with one central characteristic or several key traits that make humans unique among and/or superior to animals.⁵

As intriguing as such perceived indicators of human uniqueness are, and regardless of the scientific status of claims for such distinguishing human traits, the idea that there are particular physical features and/or behavioral characteristics that make men—and not beasts—in the image and likeness of God is not one that is found anywhere in the pages of Holy Scripture. With regard to humans as “the image and likeness of God,” a literal and consistent reading of the Genesis narratives discloses that the imago Dei designation does not refer to unique characteristics or capacities which humans posses in a way that excludes other non-human animals.

Hebrew scholar Phyllis Bird informs us that the scriptural context of the phrase “image and likeness of God” makes it plain that “its theological significance is in the place it gives to humans within the created order, not in any physical or moral attribute of the species, in either its present or ‘original’ state.”⁶ In the Bible the imago Dei is not about exceptional human capacities or characteristics that automatically qualify humans as being included in the imago Dei category. There is no reason, explains Bible scholar James Barr, to believe that the author of Genesis chapter one “had in his mind any definite idea about the content or location of the image of God.”⁷ The terms “‘image’ and ‘likeness’…make no statements about the nature of human beings.”⁸ When we read of “the creation of human beings in God’s image (Gen 1:26)…the biblical narrative remains silent…about any qualities of human nature that might account for their special standing.”⁹

If we are to properly understand the meaning of the texts, then, says Old Testament scholar Claus Westermann, we must confidently resist “the tendency to see the image and likeness of God as a something, a quality.”¹⁰ Consequently, a literal reading of the early Genesis accounts demands that no specific anthropological content or characteristics may be directly equated with the imago Dei. If one is to take the findings of biblical exegesis seriously, then—apart from theological tradition—the image of God cannot be defined on the basis of particular physical traits or behavioral characteristics. This means that—according to a straightforward reading of Genesis and the rest of Scripture—humans are not said to be biologically or behaviorally unique in a way that is related to their being named the “image of God.”

In addition to the broad consensus among biblical scholars that the image of God in humans, when understood within its original Hebrew linguistic and Ancient Near Eastern context, has nothing whatsoever to do with an appeal to the human possession of particular characteristics which non-human animals lack, research in biblical exegesis has similarly revealed that there is no essential or substantial super-natural divide between humans and other animals. Scripture, when read in the original languages, clearly describes both “man and beast” as possessing “the breath of life” and refers to both equally as “souls.” In this way Scripture makes no ontological or metaphysical distinctions between humans and non-human animals. Instead, the scriptural “emphasis lies on the commonality that exists between the humans and the rest of the animal creation.”¹¹

While the use of the Hebrew word nephesh, often translated as “soul”, to describe humans has been taken by some as an indication that humans are substantially set apart from the animals, the nephesh is not an exclusive possession of humans. Indeed, the Hebrew text describes both humans (Gen 2:7) and animals (Gen 1:21, 24) equally as nephesh hayyah or “living souls.”¹² Thus, Bible Scholar Gordon Wenham explains that in Genesis 2:7, which describes the human being as a nephesh, “it is not man’s possession of the ‘breath of life’ or his status as a ‘living creature’ that differentiates him from the animals—animals are described in exactly the same terms.”¹³ In Genesis, “human beings…are only one subset of God’s ‘living beings,’ into whom God has breathed the breath of life” and established as “living souls.”¹⁴

According to the biblical understanding, then, “what is distinctive about human beings is not that they have a ‘soul’ which animals do not possess, nor that they have a ‘spirit’ which other creatures do not possess.”¹⁵ It is clear, then, that “the possession of nepheš is not a unique characteristic of the human person.” Indeed, “unless one is ready to grant that animals have ‘souls’ in the same way that humans are alleged to have, then we might better conclude that the Genesis account is referring to the divine gift of life: ‘the human being became a living person.’”¹⁶ Consequently, “claims for a ‘special creation’ of humanity in comparison with animals and the material world conflict with the strong assertion in Genesis 2 that, physically (organically), Adam does not differ from the ‘beasts of the field.’”¹⁷ The theological language of anthropology in Genesis 1 and 2 “underscores Adam’s linkage with the animal creation, not his difference from it.”¹⁸

Whatever else the imago Dei might be, then, a clear and consistent reading of Scripture does not permit us to equate it with either a non-material soul which animals lack or some unique physical characteristic or behavior which animals lack. These conclusions regarding what the image and likeness of God in humans IS NOT lead us directly to our discussion of what the imago Dei IS.

In Part 2 of this series, Dr. Moritz examines how the phrase "image and likeness of God" is used within Scripture itself.

Notes

1. Daniel Quinn, Ishmael: An Adventure of the Mind and Spirit (New York: Bantam, 1992), 146.
2. I mention SDA because the prophecies of Ellen White and her interpretations of Genesis have played a significant role in shaping contemporary Evangelical understandings of the text. See Ronald L. Numbers, The Creationists: The Evolution of Scientific Creationism (Berkeley, CA: University of California Press, 1992), 74. For an online lecture on this topic see http://vimeo.com/38687776
3. Kay Warren, “Puppies Aren’t People: When compassion for animals goes too far,” (Accessed May 22, 2012) http://blog.christianitytoday.com/women/2009/04/kay_warren_puppies_arent_peopl.html. In this essay Kay Warren cites the theological views of her husband Rick Warren.
4. Ann Coulter, Godless: The Church of Liberalism (New York: Crown Forum, 2006), 266.
5. For example a recent group of Genesis interpreters concludes, “Evidence points to the fact that man is a unique creation, made in the image of God.” David N. Menton, “Did humans really evolve from ape-like creatures?” in War of the Worldviews: Powerful Answers for an Evolutionized Culture, ed. Ken Ham, Bodie Hodge, Carl Kerby, et al. (Green Forest, Arkansas: New Leaf Press, 2006), 43-59.
6. Phyllis A. Bird, “Theological Anthropology in the Hebrew Bible,” in The Blackwell Companion to the Hebrew Bible, ed. Leo G. Perdue (Malden, MA: Blackwell 2001), 262.
7. James Barr, “The Image of God in the Book of Genesis: A Study of Terminology, ” Bulletin of the John. Rylands Library 51 (1968-69), 13.
8. Horst Dietrich Preuss, Old Testament Theology, vol 2, trans. Leo G. Perdue (Edinburgh: T & T Clark, 1996), 115
9. Kathryn Tanner, “The Difference Theological Anthropology Makes,” Theology Today 50:4 (Jan 1994), 573.
10. Claus Westermann, Creation, trans. John H. Scullion, S.J. (Philadelphia: Fortress Press, 1974), 57-58.
11. Iain Provan, “The Land Is Mine and You Are Only Tenants (Leviticus 25:23): Earth-keeping and People-keeping in the Old Testament,” CRUX 42:2 (Summer 2006): 5.
12. Claus Westermann, Genesis 1-11: A Continental Commentary, 1st ed. trans. John J. Scullion (Minneapolis, MN: Fortress Press, 1994), 136.
13. Gordon Wenham, Word Biblical Commentary: Genesis 1-15 (Waco: Word, 1987), 61.
14. Provan, “The Land Is Mine and You Are Only Tenants,” 5.
15. Ray Anderson, “Theological Anthropology” in The Blackwell Companion to Modern Theology, ed. Gareth Jones (Oxford: Blackwell, 2004), 85 (emphasis added).
16. Joel B. Green, “Restoring The Human Person: New Testament Voices For A Holistic and Social Anthropology,” in Neuroscience and the Person: Scientific Perspectives on Divine Action, ed. Robert John Russell, Nancey Murphy, Theo C. Meyering, and Michael Arbib (Vatican City State and Berkeley, CA: Vatican Observatory and CTNS, 1999), 5.
17. Lawson G. Stone, “The Soul: Possession, Part, or Person? The Genesis of Human Nature in Genesis 2:7” in What About the Soul?: Neuroscience and Christian Anthropology, ed. Joel B. Green (Nashville: Abingdon, 2004), 50.
18. Ibid., 57.

I want to express my gratitude to those associated with BioLogos for the chance to dialogue with them. I have found their material to be challenging and thought provoking, and look forward to continuing the conversation. In the area of science, to call me a novice would be a kindness, and so to question their evaluation of the scientific evidence for the evolutionary process would be inappropriate for me. However, I do want to raise some questions about their evaluation of theological issues, especially concerning the image of God in humanity. I refer especially to their response to the question, “At what point in the evolutionary process did humans attain the ‘Image of God?’”¹

The BioLogos response begins by correctly noting that the precise meaning of the image of God has been the subject of debate throughout Christian history, but they believe the majority view sees the image of God as “characteristics of the mind and soul,” such as “the ability to love selflessly; engage in meaningful relationships; exercise rationality; maintain dominion over the Earth; and embrace moral responsibility.” They see these characteristics as being acquired through the evolutionary process, though they also state, “We do not know if humanity received the image of God by the immediate onset of a relationship with God or by a slower evolutionary process.” Further, since they identify the image with characteristics of the soul, they add in a discussion of the soul, “We also cannot know whether God directly intervened in the evolutionary process at this point [referencing Gen. 2:7], or whether the unfolding evolutionary process produced the human soul.” It is at this point I wish to question whether or not it is possible for the image of God to be produced through the evolutionary process apart from the special intervention of God. BioLogos seems to lean toward the image being produced through evolution, but is ultimately non-committal on the possibility of divine intervention. I want to argue that there is good reason to argue for the necessity of divine intervention in giving to humans the image of God.

I have no strong objection to the list of characteristics given in the BioLogos response, though I would see most of them as underlying the capacity for relationship with God, which I see as central to the image. Nor do I have any necessary objection to the idea that God used the evolutionary process in developing the brain and other physical abilities of human beings necessary for exercising some of the characteristics involved in the image. Nor do I think that Gen. 2:7 requires the direct intervention of God in implanting the soul (though it certainly allows it). The problem, rather, is in not recognizing that the image of God in Scripture seems rather clearly linked with something immaterial in the human constitution (whether it is called soul or spirit) that could not have come into being by evolutionary processes. My argument for affirming the necessity of direct intervention of God in the creation of humanity in the image of God rests on three assertions. Let me try to state and defend them.

First is the assertion that central to the image of God is the capacity for relationship with God. I do not think this would be rejected by those in the BioLogos community. Within the BioLogos response the phrase “relationship with God” is found numerous times in association with the image of God. They may not like the part about such a capacity being central to the image of God, but the fact that the image of God is what distinguishes humans from other animals in Genesis 1, coupled with the fact that it is humans, and not other animals, who engage in personal relationship with God throughout Scripture, makes a fairly strong case for linking “image of God” to “capacity for relationship with God.”

The second assertion is that this capacity for relationship with God is something that continues after the death of the body, and is associated with something in human beings that continues to exist after the death of the body. Here I recognize that there has been a growing chorus of voices advocating monistic views of the human constitution,² but they all seem to fail to account for the strong biblical evidence for human existence in the intermediate state.³ That which survives death is called the soul in some places (Gen. 35:18; Rev. 6:9-10) and the spirit in others (Eccles. 12:7; Heb. 12:23), but it is identified with the person himself in II Cor. 5:8 and Phil. 1:23. Jesus says to the thief on the cross, “Today, you will be with me in paradise” (Luke 23:43). Both of their bodies would soon be in graves, but the words “you” and “me” seem to affirm an existence apart from their bodies.

The third assertion is that whatever it is in human nature that survives the death of the body (soul or spirit) must be non-material, and could not be produced by the evolutionary process.⁴ Alvin Plantinga, in an argument against materialism, asks, “How could an immaterial soul have come to be by way of evolutionary processes?”⁵ He quotes Richard Dawkins,

Catholic morality demands the presence of a great gulf between Homo Sapiens and the rest of the animal kingdom. Such a gulf is fundamentally anti-evolutionary [and hence wholly heretical?]. The sudden injection of an immortal soul in the timeline is an anti-evolutionary intrusion into the domain of science.⁶

I would change Dawkins’ wording from “Catholic morality” to “The image of God in humans” but the conclusion is the same. I cannot imagine how an immaterial reality, which survives the death of the body, could be produced by natural processes, such as evolution, even God-guided evolution. I do not think this is a God-of-the-gaps argument that could eventually fall to advances in science, but a logical argument, based on the intrinsic difficulty of seeing how the natural and mortal could produce something immaterial and capable of surviving the death of the body. Even if someone were to question my association of the image of God with the spirit or soul (assertion 1), I would argue that the mere existence of an immaterial spirit/soul that survives death (assertion 2) yields the same necessity of divine involvement in the creation of the immaterial aspect of human nature (assertion 3), which is my chief contention.

Notes

1. Subsequent references are taken from the response given at http://biologos.org/questions/image-of-god, accessed 10/14/2011.
2. Joel Green has been perhaps the most prominent voice advocating monism (see Joel Green, Body, Soul, and Human Life: The Nature of Humanity in the Bible [Grand Rapids: Baker Academic, 2008] and Joel Green, ed., What About the Soul? Neuroscience and Christian Anthropology [Nashville: Abingdon, 2004]), though a similar view has been affirmed by a number of his Fuller Seminary colleagues who advocate a “non-reductive physicalism” (see Warren S. Brown, Nancey Murphy, and H. Newton Malony, eds., Whatever Happened to the Soul? Scientific and Theological Portraits of Human Nature [Minneapolis: Fortress Press, 1998). For a more complete presentation of views, see Joel Green, In Search of the Soul: Four Views of the Mind-Body Problem (Downers Grove, IL: InterVarsity Press, 2005).
3. John W. Cooper, Body, Soul & Life Everlasting: Biblical Anthropology and the Monism-Dualism Debate (Grand Rapids: Eerdmans, 1989) gives a strong defense for dualism primarily from the evidence in Scripture for the intermediate state.
4. I recognize the objection here of William Hasker and the idea of emergentism, or emergent dualism, in which a distinct soul or self emerges from the complex configurations of the biological organism, similar to magnetic fields generated by physical objects but distinct from them. See Hasker, The Emergent Self (Ithaca, NY: Cornell University Press, 1999), for the fullest presentation of his view. The difficulty of his view lies in attributing to material stuff the power to generate a non-material reality. This difficulty is raised by Alvin Plantinga (see n. 5 below) and others and emergent dualism is as of today still a minority view in philosophical circles.
5. Alvin Plantinga, “A New Argument Against Materialism” (plenary address for the Evangelical Philosophical Society, Atlanta, GA, 18 November 2010).
6. Ibid. No source for Dawkins is given.

In the previous post in this series, we explored how evolution can force science into making predictions that seem counter-intuitive. For cetacean (whale) evolution, we saw that the preliminary lines of evidence (the fact that whales are vertebrates, and mammals, for instance) pointed to the prediction that modern whales are descended from four-limbed, land-dwelling ancestors. As we then noted:

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”.

We have already discussed hind limb and hair loss in whales, citing evidence from embryonic development in modern whales that shows how hair and hind limbs develop early in their embryogenesis, but then are lost at later stages. We now turn to one of the remaining questions: tooth loss in the lineage leading to modern toothless whales (order Mysticeti). To obtain their food these whales pass seawater through a baleen, a large sieve-like structure that filters out plankton, small fish and other food items. Some recent genetics sleuthing has investigated a portion of this riddle, and adds further details to the story of how the baleen whales came to be.

Evolution: A Theory with Bite

If indeed modern whales are descended from ancestral, four-limbed, terrestrial ancestors, then those ancestors, like mammals in general, had teeth. Modern toothed whales (order Odontoceti) have retained those teeth to the present day, but baleen whales have adopted a new way of life as filter-feeders. Researchers were curious to see if traces of a “toothed past” could be found in the genomes of modern baleen whales, so they went hunting for remnants of genes devoted to making teeth. Such defective gene remnants would be examples of pseudogenes, and we have discussed pseudogenes previously in this series. While pseudogenes in and of themselves are powerful evidence for evolution, pseudogenes that are “out of place” are especially so. One such example we have seen before is the human vitellogenin pseudogene, the remains of a gene used for yolk production in egg-laying organisms found in the exact location in the genome that evolution would predict for it. As mammals that receive embryonic nourishment through a placenta, we have no need of egg-yolk genes. Similarly, baleen whales have no need for genes responsible for making teeth, and finding the remnants of such genes would make a strong case for an evolutionary origin of baleen whales as the modified descendents of toothed whale ancestors.

Independent Lines of Evidence, but Contradictory Stories?

Some of the genes known to be used in all mammals for tooth formation were the obvious candidate genes to start with: the products of the ameloblastin, amelogenin, and enamelin genes are all used in the formation of tooth enamel, the hardest structure in the vertebrate skeleton. Researchers went looking for these genes in several Mysticete (i.e. toothless whale) species. The results showed that all the species studied did indeed have these three genes present as pseudogenes (and more specifically, as unitary pseudogenes, a special class of pseudogene we have discussed in detail previously). Finding these genes as pseudogenes in toothless whales was exactly what evolution predicted, but there was a catch: none of the mutations that removed the functions of these three genes were shared between different species, suggesting that these genes lost their function independently in the species studied. This finding was at odds with data from the fossil record, which suggested that teeth were lost only once, and early in the lineage leading to all modern toothless whales. So, the researchers seemed to have two lines of evidence that at face value contradicted each other. The fossil record suggested that tooth loss occurred once in the common ancestor of all toothless whales, but these three genes seemed to have been inactivated independently, several times over, suggesting that loss of teeth should be happening later in Mysticete evolution, and more than once.

One proposed explanation for the apparent discrepancy (among several put forward) was to predict that a fourth gene required for enamel formation was lost early in Mysticete evolution. The loss of any one gene necessary for forming enamel would be enough to prevent the process altogether. In this case, the loss of this fourth gene would prevent tooth enamel from forming, even though the genetic sequences of the other three enamel genes would still be intact. Once enamel function was lost, random mutations in the remaining enamel genes could then accumulate later in Mysticete evolution after speciation in this group was already underway. To test this hypothesis, the research group went hunting for other enamel genes in toothless whales.

Signature in the SINE

The smoking gun for tooth loss in Mysticetes turned out to be exactly what was predicted: a fourth gene, necessary for enamel production, and mutated with the same inactivating mutation in all modern toothless whales. The gene in question, named enamelysin, was destroyed when a mobile genetic element called a SINE transposon inserted into it, breaking it into two halves and removing its function:

The fact that the same SINE insertion mutation at an identical location is found in all modern Mysticete species indicates that this mutation happened once in a common ancestor and then was inherited by the entire group. Since this must have occurred early in the evolution of toothless whales in order to happen in the common ancestor of the entire group, the picture from the genetics and the fossil record match. Once again, findings in one discipline (in this case, paleontology) can be used to make very detailed predictions about what another, unrelated discipline (comparative genomics) should reveal. These results are also entirely consistent with the observation, made in the 1920s, that toothless whales form tooth buds during embryogenesis that are later reabsorbed prior to the point when the deposition of enamel would begin. As with the hind limb story in whale evolution, lines of evidence from genetics, paleontology and embryology converge to support the hypothesis that modern toothless whales descend, through modification, from toothed ancestors.

In the next post in this series, we’ll examine a few more lines of evidence for whale evolution, and extend our discussion to converging lines of evidence for the evolution of our own species.

For further reading:

Meredith, R.W., Gatesy, J., Cjeng, J., and Springer, M.S. (2011). Pseudogenization of the tooth gene enamelysin (MMP20) in the common ancestor of extant baleen whales. Proceedings of the Royal Society B: 278 (1708); 993 – 1002. Available online: http://rspb.royalsocietypublishing.org/content/early/2010/09/16/rspb.2010.1280.full.pdf

Ridewood, W.G. (1923). Observations on the skull in foetal specimens of whales of the genera Megaptera and Balaenoptera. Philosophical Transactions of the Royal Society of London B: 211; 209 - 272. Available online: http://rstb.royalsocietypublishing.org/content/211/382-390/209.full.pdf

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Today's video is courtesy of filmmaker Ryan Pettey, director/editor of Satellite Pictures, and features Dr. Rick Colling, biologist and author of Random Designer.

In today’s video, Dr. Rick Colling states that one of the biggest difficulties in communicating compatibility between evolution and faith is a misunderstanding of what evolution is. Evolution is not, he says, about the imposition of death and destruction and survival of the fittest. Rather, it is about second chances. Our bodies contain thousands of genes, which duplicate like a computer back-up copy and can serve as raw material. When an organism encounters adverse environmental condition, this raw material can be used to help adapt and survive.

“God is so creative," says Colling, "that he’s actually put into place a mechanism to start doing these gene changes in advance before they’re even needed. And God has given us a second change through the evolutionary process of creating duplicate genes that give rise to new raw material that give rise to new possibilities, and that really more accurately describes the process of evolution. It’s redemption, it’s possibility, and it’s hope.”