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

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

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

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

Transitional Fossils

Some time ago, the Discovery Institute’s Casey Luskin commented on the human origins exhibit at the Smithsonian Institution, suggesting that palaeoanthropologists use evolutionary theory to describe the progression of the human lineage even when they don’t have transitional fossils with which to work. He writes:

What's ironic, however, is that if you ask the question How Do We Know Humans Evolved? the answer you’re given is, “Fossils like the ones shown in our Human Fossils Gallery provide evidence that modern humans evolved from earlier humans.” So whether you find fossils or you don’t, that’s evidence for evolution.

Indeed, it has become an article of faith for those espousing both the young earth creation (hereafter YEC) model and many who hold to the intelligent design model that transitional fossils do not exist and therefore evolution has not taken place. Support for this position usually entails attacking the weak areas of the fossil record, where burial processes have left us little with which to work, or the creation of straw men arguments in which transitional fossils are defined in such a way that none could ever be found. Often this centers on the concept of “missing link,” a term that is habitually used in the popular press and young earth creation and intelligent design literature when referring to fossil remains but which has little to no meaning for biologists or palaeontologists. As Ahlberg and Clack (Ahlberg and Clack 2006) write:

But the concept has become freighted with unfounded notions of evolutionary ‘progress’ and with a mistaken emphasis on the single intermediate fossil as the key to understanding evolutionary transitions. Much of the importance of transitional fossils actually lies in how they resemble and differ from their nearest neighbours in the phylogenetic tree, and in the picture of change that emerges from this pattern.

Contrary to common misconceptions, the fossil record does not record one single lineage for any family of organisms but rather a series of branches, with many related species coexisting synchronously. Darwin hypothesized that the evolutionary record reflected this bushiness and drew such a diagram in his journal. At the time, though, he had little in the way of fossil evidence to back up this position. Much has changed since his day.

An analogy for understanding this “bushiness” was best described by Prothero and Buell (Prothero and Buell 2007). They suggest that the reader consider his or her own genealogy. You and your siblings are the direct descendents of your parents and, while you are similar to them, each of you has different characteristics not shared with them as well as characteristics that you do share. Your parents have siblings as well (your aunts and uncles), and your grandparents are their last common ancestors. These siblings have their own children (your cousins), who have different and similar traits relative to their parents. They are broadly recognizable as being related to you (“oh, I see you have Aunt Edna’s nose”) but three or four generations out, they will become less and less so. These are the “nearest neighbours” that Ahlberg and Clack describe. In this analogy, each of these cousins represents a transitional form from what was (your grandparents) to what will be down the road.

For example, no one would confuse a frog with a salamander but if you trace the fossil record of each back in time, eventually you encounter a fossil, Gerobatrachus hottoni which was recently discovered (Anderson et al. 2008) that is best described as a “frogamander,” having the basal characteristics of both frogs and salamanders. Had we seen such an animal at the time, it is likely we would not have found it remarkable because it would have resembled the species around it. One lineage eventually diverged into frogs, salamanders and other amphibians. Most (just like Darwin proposed in his tree diagram with the little hatch marks at the tip of many branches) went extinct.

Taxonomy and the Beginnings of Human Origins

All life is classified based on a system devised by Carolus Linneaus in 1735 in his remarkable work Systema Naturae. This system gives all recognized species an individual place based on a system of hierarchy. The study of classification is known as taxonomy. A taxonomic ranking for humans would be this:

When a fossil is excavated, the first thing that the palaeontologist does is make a taxonomic assessment of where it fits in a sequence of known fossils. Traits that are shared with other like species or genera are referred to as primitive traits. Examples of this in humans are five fingers and the presence of three arm bones. We share this with all mammals. Traits that are new or are not shared with other like species are referred to as derived traits. Examples of this in humans are the skeletal changes in the pelvis and the foot to allow for walking upright. We do not share these with any other primates.

Transitional fossils in the human fossil record are distinguished at both the genus and species level. This group includes the extinct genera Ardipithecus and Australopithecus and the current genus Homo. All species except Homo sapiens are extinct. Much of the recent study of early humans focuses on the transition from Ardipithecus (‘Ardi’) to Australopithecus (‘Lucy’ and similar fossils) and from Australopithecus to Homo, the genus that led eventually to us. While each of the australopithecine species identified in the fossil record has derived characteristics that separate them from their ancestors and from each other, only one led to the genus Homo.

In future posts, I will describe the evidence for human evolution and why this evidence is compelling. It suggests that we have had a long, varied history filled with great leaps of change, crushing defeat, and eventual expansion into all areas of the globe.

Notes

Ahlberg, P. & J. Clack (2006) A firm step from water to land. Nature, 440.

Anderson, J. S., R. R. Reisz, D. Scott, N. B. Frobisch & S. S. Sumida (2008) A stem batrachian from the Early Permian of Texas and the origin of frogs and salamanders. Nature, 453, 515-518.

Prothero, D. & C. Buell. 2007. Evolution: What the fossils say and why it matters. Columbia Univ Pr.

Today, as I write, I am no longer in the desert of southern California, nor in the beech-maple forest of New Hampshire, but on a glacial drumlin in Waubesa Wetlands—a large marsh four miles south of Madison, Wisconsin. Here Ruth and I have our home, and here I study creatures whose watery habitats my neighbors and I have worked to save from eventual destruction. While my desert study site now is covered by a city where people live alone in the land—absent the desert creatures—my wetland study site remains occupied by all kinds of native plants and animals. Embracing it is the Town of Dunn, whose land stewardship plan helps people understand, serve, and maintain this and the other ecosystems. Our town stewardship plan encourages restoration of the landscape, protects agricultural lands, and strives to transmit an intergenerational heritage of secure and wholesome homes, livelihoods, and habitats for the animals, plants, and people that live here. We live largely in harmony and accord.

House-building on slabs poured onto desert sands first alerted me to the question of praxis, the third point on the napkin. But it was later, in my work as organizer of the Waubesa Wetlands Scientific and Agricultural Preserve, and as supervisor and later as chair of the Town of Dunn, that I came to realize that science and ethics do no earthly good unless put into practice. In serving my town, I came to apply what I had learned in the desert: praxis uninformed by science and ethics usually creates more problems than are solved.

“How do you put it all together?” those students in New Hampshire wanted to know. For me, it was building a framework for stewardship that simultaneously considered the questions “How does the world work?” “What is right?” and “What then must we do?” This science-ethics-praxis triad is a framework for living, for learning, for teaching, and most importantly for acting. It is a framework for stewardship.

In order to live and act rightly in the world, we need to know how the world works. We need to know how the systems that sustain us work, and how we interact with them. Without such knowledge we could drown in a flash flood, have our homes undercut by desert winds, cross the street in the path of an oncoming car, or get sick from consuming foods with toxic ingredients. As human beings develop more and more of the world, and as the reach of human actions extends regionally and globally, our knowledge must increase accordingly. This knowledge is not limited to what we acquire from a formal education; it also includes the knowledge we gain from family and friends, and from experience and experiment. In order to live and act rightly in the world, we need to know how the world works.

In order to live and act rightly in the world, we need to know what we ought to do. A century ago, this question was addressed in many colleges across America in a course for graduating seniors on moral philosophy. The purpose of this course was to convict students that they should apply their knowledge for the pursuit of good instead of pursuing self at others’ expense. At my university, this aspect of college education is expressed in a quotation from Abraham Lincoln carved in stone on a bench behind Lincoln’s statue at the top of Bascom Hill: “Let us have faith that right makes might, and in that faith, dare to do our duty.” The question “What is right?” is represented by the ethics corner of our triad. Moving directly from the Science corner to the praxis corner, or from the ethics corner to the praxis corner, proves problematic, even disastrous. Consider the result of going from knowledge of nuclear fission (science) directly to producing and dropping an atomic bomb (praxis), or moving from the belief that death is bad (ethics) to removing dead wood from forests (praxis); both are examples of these disastrous shortcuts.

But knowing the science and observing the ethics of this stewardship framework does absolutely no good if it is not put into practice—placed into service. By themselves, the very best science and the most substantial ethics are no substitutes for action. We need to act appropriately and deliberately in the light of scientific and ethical knowledge. Praxis by itself, without being grounded in science and ethics, results in mere activism—activism that is unlikely to do good and that may produce harm. All three corners of the triad are essential—but not by themselves. Taken together and working interactively, they provide a framework for stewardship.

But will these three operate in dynamic interaction? Will they interact in ways that preserve and achieve the integrity of human life and the environment? The answer depends on what we know and understand about ourselves and the world (science), what we believe we should do (ethics), and what we in fact do, and how we respond to our successes and failures (praxis). It depends on our will, our motivation, our determination, and our dedication to strive for a harmonious world of creatures before their Creator. What might make us strive for such a world?

Part 3 explores the challenge of translating ideals into concrete actions.

A careful study of this chapter is important because it gives us a beautiful picture of the proper relationships we should have with God, the natural world, and each other. Numerous posts could be written on each of these relationships, but in this post I’d like to focus on how Genesis 2 describes our relationship to the rest of creation. These relationships are given deeper significance when we recognize that the garden is being described as a temple-like “sacred space,” not just an ordinary garden. There are numerous clues in the passage that this is the case. John Walton writes that the Garden/temple parallels “are givens that are simply assumed by the author and audience” ¹ of Genesis, but we completely miss them if we take fail to read the text the way the ancient author and audience would have.

Temples and Gardens

In the Ancient Near East (ANE), all sacred space was conceived of as something like a temple; it was a place where humans would serve God and experience their closest access to Him. Thus in ANE cultures, a temple complex was seen as being the apex and a microcosm of creation and the earthly abode of the god(s). Descriptions of temples often pictured a river flowing from under the temple and flowing out through an adjacent garden, symbolizing the fertile extravagance of the divine provision. A temple garden would be no mere backyard vegetable patch, but rather an elaborate, beautifully landscaped botanical park.

The same temple/river picture can be seen in the description of the eschatological temple in Ezekiel (ch. 47) and Revelation (chs. 21-22, where the final temple is God Himself). Sound familiar? In Genesis 2 we also have a river flowing “from Eden [‘Abundance’] to water the garden” (v. 10).² Not only is the Garden filled with “every beautiful tree with edible fruit” (v. 9), but the area itself is rich with gold, resins, and gemstones (sometimes translated “bdellium and onyx”), the same materials later used to decorate Israel’s tabernacle, temple, and priestly garments. Furthermore, many scholars are convinced that the design of temple’s Menorah (candlestick) deliberately echoes the Garden’s Tree of Life, and some also think that the Ark of the Covenant in the temple parallels the Tree of the Knowledge of Good and Evil.³

Made for Sacred Service

As inhabitants of this temple-garden, it comes as no surprise that Adam and Eve enjoyed a special closeness to God’s presence (Gen. 3:8 pictures God taking an evening walk through the Garden). But as inhabitants of the Garden, they had special responsibilities as well; they were told “to farm it and take care of it” (v. 15). The two Hebrew words used here have a broader range of meaning than their English translations suggest. As John Walton writes, the broader meaning of the word here translated “to farm” (particularly when used in a sacred context) “is often connected to religious service deemed as worship (e.g., Ex. 3:12) or of priestly functionaries serving in the temple precinct (e.g., Num. 3:7-10).” ⁴

The usage in Genesis 2 seems to have two layers of meaning: “farm/cultivate the Garden” (since it is an agricultural space) and “serve/worship God” (since the Garden is also a sacred space). The dual meanings are as intertwined in Hebrew grammar as they are intended to be in practice. The second Hebrew word (translated “take care of”) has a deeper religious meaning as well. The word can refer to protecting farmland from external threats, but in a danger-free sacred space like the Garden, the word more generally refers to “performing duties on the [temple] grounds,” that is, to “sacred service.”⁵

Walton therefore translates these two Hebrew words as “serve and preserve.” These same words appear again together several times in Numbers to describe the priest’s duties in the temple. Because of all this, Gordon Wenham describes Adam as “perhaps…an archetypal Levite” with a “quasi-priestly” role in the garden.⁸ Eve was created as Adam’s companion and “helper” in his work, a word which nowhere in the OT refers to a subordinate assistant, but rather to one who is at least equal to the one being helped.⁹

Genesis 2 should banish from our minds any idea that creation care is somehow “secular” work for a Christian, or that it is not even our responsibility. This was the first task given to humanity, to serve and worship God by cultivating and protecting the natural world. The centrality of our responsibility in this regard is even clearer when we back up to the beginning of the chapter. We know there was a river “flow[ing] from Eden to water the garden” (v. 10), symbolizing that “all fertility emanates from the presence of God.” ¹⁰ Nonetheless there could be no cultivated plants in the garden because “there was still no human being to farm the fertile land” (v. 5). With no gardener and no rain, the ground was watered indiscriminately; a human was needed to irrigate the waters and support a garden.¹¹ Therefore, God “formed the human from the topsoil” (Hebrew wordplay equivalent to “human from the humus”) before planting the garden. God certainly could have watered it another way without needing us, but He chose not to, and the resulting collaborative picture here is a beautiful one. All provision flows from God, but He has chosen to give us an essential part in further channeling his provisions in the natural world. Far from countering God’s creative work by destroying nature, we are intended to work with Him to preserve and further it.

Of course, though created primarily to glorify God, the world was also made to provide us abundantly with the food and resources that we need to live (Gen. 2:16). Yet we don’t need to look far to see that we have often failed in our responsibility to properly care for creation. We live in a fallen world, and sin has fractured the intended harmony of our relationships with God, creation, and each other (as described in Genesis 3:14-24).

I recently heard a striking crystallization of this fallen perspective in Spencer Tracy’s narration in the opening scene of the sprawling 1962 western film “How the West Was Won.” As the camera flies over majestic Western fields and mountains, the narrator tells us that “This land has a name today, and is marked on maps. But the names and the maps all had to be won, won from nature and from primitive man.” This is the fallen perspective – advancing our human purpose on earth is done through defeating nature and other people (derogatively labeled “primitive,” as well) apart from God. This perspective perfectly illustrates the conflict-based relationships that sin brings about, already described for us back in the first chapters of the Bible.

Are we doomed, then, to live helplessly in this way? If this is just the way the world is and the way we are, shouldn’t we just accept that? Apart from Christ the answer would be “yes,” but the New Testament makes it clear that though we are still fallen, the saving work of Christ has brought about a profound change in us. As N.T. Wright makes clear in his book Surprised by Hope, Jesus taught (and the Resurrection vindicated) that the Kingdom of God “was and is breaking in to the present world, to earth.” ¹² Christ’s Resurrection was the first act of the future new creation. If we are truly “born again” into this new reality, this new way of living, we must strive (in the Spirit’s power) to live lives of wholeness and right relationships, putting our sinful nature to death (Colossians 3). In doing so, we would be wise to include Genesis 2 as we seek to follow God’s will and God’s Kingdom, “on earth as it is in heaven” (Matt. 6:10).

In part 2 of this series, David describes how Genesis 1, Genesis 2, and modern scientific accounts offer complementary and mutually enriching perspectives in our understanding of God's creation.

Notes

1. John H. Walton, Ancient Near Eastern Thought and the Old Testament: Introducing the Conceptual World of the Hebrew Bible (Grand Rapids, MI: Baker Academic, 2006), 125.
2. Biblical quotations are from the Common English Bible unless otherwise noted.
3. Both symbolized divine wisdom that humans had to receive from God obediently, with the proper “fear of God” that the Old Testament wisdom literature stresses as a prerequisite. Disobediently eating the Tree’s fruit would lead to death and disobeying God would lead to expulsion from the Garden. Similarly, disobediently touching the Ark brought death (Num. 4:15, 2 Sam. 6:1-7) and disobeying God’s instruction led to Israel’s exile from their Eden, the land of Canaan.
4. John H. Walton, Genesis (Grand Rapids, MI: Zondervan, 2001), 172.
5. Ibid., 173.
6. Ibid., 192.
7. See Numbers 3:7-8, 8:26, 18:5-6.
8. Gordon J. Wenham, “Sanctuary Symbolism in the Garden of Eden Story,” in “I Studied Inscriptions from Before the Flood”: Ancient Near Eastern, Literary and Linguistic Approaches to Genesis 1-11, ed. Richard S. Hess and David Toshio Tsumura (Winona Lake, IN: Eisenbrauns, 1994), 401.
9. Walton, Genesis, 176.
10. Ibid., 170.
11. This follows Walton’s illuminating exegesis of this passage in Genesis, 164-65.
12. N.T. Wright, Surprised by Hope: Rethinking Heaven, the Resurrection, and the Mission of the Church (New York: HarperOne, 2008), 201.

Introduction

One of the reasons that some of us are hesitant to accept evolutionary creation is that it seems to make God responsible for the suffering and death of innumerable creatures over millions of years—before humans ever existed or sinned against their creator. Since we believe in and worship a God who is loving, benevolent, and all-powerful, it sounds quite implausible that our God would have created a world like that; therefore, any scientific evidence for evolution must be incorrect.

Other people look at the scientific evidence for evolution and find a compelling case that it has taken place during our earth's history. On this basis they may conclude that if evolution is true, then the belief in an all-powerful, perfectly good God must be false!

The trouble with both of these views is that they tend to invoke a completely abstract, philosophical god, not the living God of the Bible—the God who became a human being, experienced unimaginable suffering, and died in a grotesque and humiliating public display. The death of Jesus completely defied the expectations (and common sense) of his followers, as well as the expectations of any “rational” understanding of the way the Creator of the universe should act in the world. On the cross, in the person of Jesus, God took upon himself far more suffering than any creature has ever experienced.

If God himself is willing to die, particularly in such a gruesome way, then perhaps we should at least consider the possibility of God allowing the death of other creatures, too. But would this really be compatible with what we know of God through Scripture? In this essay, we will explore this quandary through a “theology of the cross”, a concept articulated by pastor George Murphy in his book Cosmos in the Light of the Cross.¹

Theology of the cross

Before we jump into the theological problems associated with evolution, let’s take a look at how we understand Christian theology itself. For the reformer Martin Luther, any theology (or science) that tries to reach knowledge of God apart from the cross is bad theology.² Instead, Luther pointed to a theologia crucis, in which the true God is seen first and foremost “through suffering and the cross”. To make his point even clearer, Luther insisted that “the CROSS alone is our theology”.³ It is the lens through which we view everything.

Of course Martin Luther, having lived in the 16th century, was not aware of the vast history of life on our planet (or any other aspect of modern science, for that matter), but George Murphy draws from Luther’s teachings the foundation that all human knowledge begins with the Word made flesh and crucified.⁴ With the cross of Christ as the ultimate framework through which we view reality, we are bound to view the processes of nature quite differently. As Murphy explains it,

A theology of the cross is an explication of belief in a God who becomes a participant in the history of the universe and thereby shares in the suffering, loss, and death that are part of worldly experience.⁵

God does not sit idly by and watch unaffected as his creatures suffer, but neither does he swoop in and make everything completely effortless and easy. Instead he chose another way, the crucifixion of Jesus—certainly not the approach that we would have preferred! The apostle Peter went so far as to try to talk Jesus out of it, but he was met with a stern rebuke (Matthew 16:21-23).

Why is evolution so disconcerting to Christians?

The problem of suffering throughout all of human history is troubling enough for us to reconcile with a loving, personal God. But in addition to that, the discovery of vast numbers of fossils reveals that death has taken place on a far greater scale than we had ever imagined. Both the wide variety of extinct creatures and their sheer numbers is quite staggering, and it raises questions about our Creator:

The picture of a God who is immune from suffering and death but who forces organisms through millions of generations and extinction is disturbing to those who believe in a God of love.⁷

The mass extinction of life on earth was already well established by the early 19th century—decades before Darwin’s research—and extinction can be empirically verified independent of any theory of evolution.⁸ The fact that the earth’s crust is a veritable graveyard of long-lost creatures is deeply troubling, and as late as the 1790’s, distinguished intellectuals such as Thomas Jefferson denied the very possibility of extinction.⁹

But in addition to the reality of species extinction, the theory of evolution by natural selection proposes that new species also arise in an environment containing widespread pain and death. Both the creatures that are now living and those that are gone are tainted by an “acrid smell of death”.¹⁰ It makes us wonder, if our Creator is not the God of the dead, but of the living (Mk. 12:27), where is God’s presence in the evolutionary picture?

In all honesty, creation through evolution is not what we would expect from God, but Scripture is full of examples in which God acts in unexpected ways. After all, God’s choosing to undergo an agonizing death on a cross is not what we would expect from the all-powerful Creator of the universe, either. In both cases, new life comes about through pain, suffering, and death. As George Murphy puts it,

A priori ideas about God have to be overcome, and God's character has to be learned from God's self-revelation.¹¹

God’s fullest self-expression is in Jesus Christ himself, one who is intimately familiar with and personally endured creaturely pain and death. The theology of the cross reveals that God's self-revelation takes place in situations of suffering, loss, and apparent hopelessness, much like situations that occur through natural selection.¹²

The crucifixion is disconcerting too

Not only is creation through evolution an unexpected and unsettling process, but so is the crucifixion of Jesus! Killing someone by hanging them on a cross is an unbearably painful, prolonged, humiliating form of death. It was such a horrific type of public execution that it wasn't until after the Roman Empire stopped the practice of crucifixion—and people no longer witnessed it personally—did the cross become a visual object of devotion.¹³ Our culture is sufficiently removed from crucifixion that we are desensitized to its original significance, but to connect it to our current context, imagine the reaction you would get by wearing jewelry designed to look like an electric chair.¹⁴

Once we are more attuned to the brutality of crucifixion, it seems all the more striking that the cross is the sign of God’s work, what George Murphy calls “the trademark of God”.¹⁵ The suffering and death of Jesus is featured prominently in the Gospels, but the crucifixion-resurrection pattern is strongly resonant within the Old Testament, too. Israel suffered and toiled as slaves in Egypt for centuries before they were rescued in the Exodus, bringing life to a people who were spiritually dead. Centuries later, the nation of Israel would experience death again when the Babylonians destroyed the Davidic monarchy, burned their Temple, killed their people, and sent many into exile.¹⁶ Neither Israel (God’s chosen people) nor Jesus (God’s own son) were spared from death and suffering; rather, suffering seems to have been the way in which God re-forms and renews humanity to fully bear His own image.

Redemption extends to all of creation

Fortunately, God’s story does not end with death. God gives new life after his creatures have been subjected to terrible circumstances. Redemption was promised to Israel itself—Ezekiel’s vision of the valley of dry bones describes how God would renew His chosen people (Ezek 37:1-14). Later, the astonishing resurrection of Jesus made salvation possible not only for Jews, but for all people in Christ (Gal 3:26-29). Ultimately, the New Testament makes it clear that God’s renewal will encompass the entire Creation:

For God was pleased to have all his fullness dwell in him, and through him to reconcile to himself all things, whether things on earth or things in heaven, by making peace through his blood, shed on the cross. (Colossians 1:19-20)

With all wisdom and understanding, he made known to us the mystery of his will according to his good pleasure, which he purposed in Christ, to be put into effect when the times reach their fulfillment—to bring unity to all things in heaven and on earth under Christ. (Ephesians 1:8-10)

Christians are accustomed to thinking of the death of Christ in regard to humans, but our culture rarely acknowledges God plan for the redemption of His entire creation. This is partly attributable to the fact that discussions of creation and origins are often separated from the topic of salvation.¹⁷ In doing so we tend to marginalize Jesus as we argue about Genesis. Rather than fall into this trap, if we view nature through a theology of the cross, we will see Christ as both the alpha and the omega point in discussions of life’s history and life’s future. With this perspective, we are more apt to sense our solidarity with the rest of creation as we wait in eager anticipation of a glorious future:

The creation waits in eager expectation for the children of God to be revealed. For the creation was subjected to frustration, not by its own choice, but by the will of the one who subjected it, in hope that the creation itself will be liberated from its bondage to decay and brought into the freedom and glory of the children of God. (Romans 8:19-21)

Conclusion

As part of the Church’s conversation about the problem of natural evil, this essay is meant to be a brief introduction to a “theology of the cross”. One can explore this concept in greater detail in Murphy’s book The Cosmos in the Light of the Cross. While there is a lot more to be said, let me conclude with the following observation: though evolution may not be compatible with some interpretations of Christianity, evolutionary creation is certainly compatible with the crucified Christ and the theology of the cross. In the person of Jesus, God suffers with the world and ultimately redeems it. As George Murphy puts in, “The world's pains are God's stigmata.”¹⁸

Explore this Topic Further

• Miller, Keith. “And God saw that it was good”: Death and Pain in the Created Order. BioLogos series
• Murphy, George L. The Cosmos in the Light of the Cross. Harrisburg, PA: Trinity Press, 2003.
• Murphy, George L. “Cross, Evolution, and Theodicy: Telling It Like It Is”. In The Evolution of Evil. Edited by G. Bennett, M.J. Hewlett, T. Peters, and R.J. Russell. Göttingen: Vandenhoeck & Ruprecht, 2008.
• Southgate, Christopher. The Groaning of Creation: God, Evolution, and the Problem of Evil. Louisville, KY: Westminister John Knox Press, 2008.

Notes

1. Murphy, George L. The Cosmos in the Light of the Cross. Harrisburg, PA: Trinity Press, 2003.
2. Murphy, p34
3. “CRUX Sola Est Nostra Theologia,” in D. Martin Luthers Werke, Kritische Gesammtausgabe (Weimar: Hermann Boehlau, 1892), 5:172. The captitalization is in the original. Cited in Murphy, p26.
4. Murphy, p108
5. Murphy, p4
6. Murphy, p43
7. Murphy, p3
8. Some Christians ascribe animal death to some combination of Adam’s fall and Noah’s flood, but this does not resolve the problem that the animals are still suffering and dying through no fault of their own. See Keith Miller’s BioLogos series Death and Pain in the Created Order for the limitations inherent in a fall-based theodicy.
9. Rudwick, Martin. The meaning of fossils: Episodes in the history of paleontology. Chicago, University of Chicago Press, 1985.
10. See Jeff Schloss’ BioLogos essay Evolution, Creation, and the Sting of Death
11. Murphy, p63
12. Murphy, p122
13. Murphy, p27
14. This example is drawn from an evangelical outreach event held by a Christian student group in Innsbruck, Austria. On campus one day, they started conversations with their classmates by asking the question, “Would you wear an electric chair on your neck?”
15. Murphy, George L. The Trademark of God: A Christian Course in Creation, Evolution, and Salvation. Wilton, Conn.: Morehouse-Barlow, 1986.
16. Murphy, Cosmos in the Light of the Cross, p 31-32.
17. Murphy, p35
18. Murphy, p87

The first video, “10 Questions with Katherine Hayhoe”, introduces the scientist in a brief and lighthearted interview. Hayhoe is presented with 10 questions concerning her personal life and beliefs. When asked, she explains that one thing people should know about Christianity is that having a relationship with the God of the universe is one of the most incredible experiences that a person can have. As the video unfolds, the viewer quickly begins to realize that, despite her unique profession of two seemingly incompatible beliefs, Hayhoe is a remarkably sane and “normal” individual. Her role model, she explains, is her father-- the person who first introduced her to science and showed her that it could be “really cool”. On a more serious note, the scientist admits that being both a scientist and a Christian can be difficult. The most frustrating thing about her position, she says, is the amount of disinformation which is targeted at her very own Christian community.

In the second video, “Climate Change Evangelist”, Katharine Hayhoe delves into deeper discussion of the perceived conflict between climate change and Christian faith. She explains that admitting her identity as a Christian scientist can be uncomfortable. Since evangelicals are the targets of much disinformation concerning science in general -- and specifically the science surrounding climate change -- many people in the church have a misguided view of the subject and do not look kindly at her career choice. One woman encountered by Hayhoe at a church in Texas, for example, believed that global warming was a lie taught in schools to mislead her children. In an effort to realign misguided views like these, Katharine Hayhoe and her husband wrote a book addressing the deep-rooted emotions often associated with climate change. People fear that addressing the climate issue will bring forth changes in the economy and uproot their way of life. However, Hayhoe encourages her viewers to act out of love, as the Bible calls us to do, rather than out of fear. Acting out of love inspires us to consider the poor and disadvantaged people around the globe when we respond to the reality of a changing climate.

In the final segment of this three part video montage, Hayhoe addresses the question of what climate change means. Specifically, she is concerned about how global warming affects people on a personal level. While global warming generally brings to mind melting ice caps and polar bears, its implications are far more widespread, affecting the lives of everyone around the world- from cotton farmers in Texas to public health workers in Chicago. If nothing is done to change current emission levels, the number of days per year which exceed 100 degrees Fahrenheit, for example, will begin to increase dramatically, and if emissions are increased, many areas will even develop extreme conditions like those seen currently in Death Valley. Hayhoe’s goal is to demonstrate clearly that the only way to preserve the world for future generations is to significantly reduce dependence on inefficient means of getting energy and instead transition to cleaner renewable energy sources.

Editor's Note: These videos first appeared on the Nova program "The Secret Life of Scientists & Engineers".

In Part 2 of this series, we concluded by noting that, as Christian geologists willing to consider the possibility, we find no compelling evidence that the earth’s geological features can be explained by a global Flood. Here we consider three lines of evidence: global salt deposits, the order of deposition of sediment layers in the Grand Canyon, and the sequence of fossils in geological strata.

Salt Deposits

There are many places around the earth with layers of salt, some thousands of feet in thickness. Just off the southern coast of the United States in the Gulf of Mexico, thick salt deposits sit beneath thousands of feet of sediment (Fig. 1). These deposits lie within the layers that are said to have been deposited by the Flood.

We understand how salt beds form. At locations such as the Bonneville Salt Flats of Utah, or at the Dead Sea at the border of Israel and Jordan, salt is actively forming. Salt beds form when water is evaporated. During evaporation, the concentration of dissolved ions increases until the water cannot hold the salt in solution anymore and mineral salt begins to form. If a presently unknown or poorly understood process could produce salt without evaporation, as argued by young-earth advocates¹, it would quickly dissolve as soon as it came into contact with flood water, just as the salt from your saltshaker rapidly dissolves when added to water or moist food.

One might argue that the waters from the Flood could have evaporated to leave behind the salt deposits we see today, but there is a serious problem. The thousands of feet of sediment on top of the salt is also said to be from the Flood, meaning the flood waters cannot have evaporated to produce the salt and still be present and violent enough to transport thousands of feet of sediment to the same location. In other words, a single flood cannot be called upon to explain both the salt and the overlying sediment. For those who wish to argue that natural processes could have been vastly different during the Flood, there are at least two replies. First, under such a scenario, there is no point in Flood Geology studies any more than in normal studies, for nothing could be gained by the study of unknowable processes. A more important question, however, would be to ask why God would alter natural processes just to make Flood sediments look like they are not flood sediments. What would the purpose be? (We will revisit this thought later.)

Grand Canyon: Order of Deposition

The Grand Canyon is made up of a sequence of layers that defies any reasonable attempt to explain by a single flood. The alternating layers of limestone, sandstone and shale each form in unique environments. If these deposits were formed at different times under various sea-level stages, it is quite simple to explain the different grain sizes and rock types as a function of depth and distance from the shore line. If explained with a single catastrophic flood that abided by God’s natural laws of physics and chemistry, logic must be stretched beyond the breaking point.

As a very simple observation, consider instructions given in virtually every gardening book. A good soil will have a mix of sand, silt and clay. To determine the quality of your soil, you take a handful or two, put it in a clear container, add water and shake it up. When you stop shaking, the coarse grained material will settle out first resulting in a sequence of layers: sand on the bottom, then silt, then clay. You can readily see how much of each you have by the thickness of each layer.

This is informative of what we see in flood deposits. As moving flood waters slow down, finer and finer grained sediment settles out resulting in a “fining upward” sequence. If most of the Grand Canyon layers were laid down by the Flood, then we should see the same thing – a “fining upward” sequence. Instead, we see a series of alternating layers of fine and coarse grained material, with smaller-scale alternating layers within the larger ones (Fig. 2). Increasing the violence of a flood does nothing to negate the standard order of deposition. Repeated surging of flood waters across the surface likewise offers little explanatory power; in this case we might expect successive layers, each with their own “fining upward” sequence, but such is not what is observed. Further, the Grand Canyon includes multiple layers of limestone, which are never found in flood deposits of any magnitude. Even in floods as massive as one thought to have catastrophically deluged the once dry Mediterranean Sea basin with thousands of feet of water – limestone beds are conspicuously absent.

Fossil Sequence

If a massive flood were responsible for the fossil record, what would we expect to see? If the Flood was violent enough to rip chunks of rock up from the earth and move entire continents (standard Young Earth claims)², then it should be obvious that life forms from every imaginable niche would be tumbled and mixed together (Fig. 3a). We should find numerous examples of mammoths mixed with triceratops, and pterodactyls mixed with sparrows. Ferns and meadow flowers should be found in the same deposits, along with trilobites and whales. Further, we should find all major life forms still living today, for Genesis 7:8-9 is clear in stating that all terrestrial animals were preserved on the ark.

What we actually observe is far different (Fig. 3b). There is an orderly sequence where trilobites only occur in very old rocks, dinosaurs in later beds, and mammoths in still later layers. Organisms like flowers and ferns are present together in more recent deposits, but only ferns with no flowers are found in older deposits. Some readers will recognize this as an example from the “geologic column” and be tempted to discount it as a fabrication. For those thinking this way, consider what Henry Morris had to say in both editions of Scientific Creationism:

“Creationists do not question the general validity of the geologic column, however, at least as an indicator of the usual order of deposition of the fossils…”⁵

If we revisit the Grand Canyon for a moment, is it not striking that there is not a single dinosaur, mammoth or bird in the entire exposed sequence? Not one. To find these, you have to go to younger sediments found in deposits outside the canyon that have not been fully eroded away yet. How could such a lack of mixing be possible if the Flood was violent enough to move continents?

For more, be sure to read our FAQs How are the ages of the Earth and universe calculated? and What scientific evidence do we have about the first humans?, as well as our recent infographic How Do We Know the Earth is Old?.

Author's Note from Joy Walters

As I mentioned in my first post, I grew up skeptical of the whole idea of evolution. One contributor to my disbelief was the lengthy timescale for the “tree of life” that was presented with the theory. I would hear, for example, that dinosaurs lived hundreds of millions of years ago, but there was no explanation of why this was true; it was just given as a fact. No one explained the methods of dating, and so I thought biologists simply estimated the ages of species to fit their preconceived notions of how long it would take for one species to emerge from another. It also seemed like the ages were periodically revised and extended farther back in time, and I figured scientists needed to manipulate numbers to make evolution plausible. This, in my mind, made the theory both unbelievable and dismissible.

Once I learned about the techniques used to date fossils, I realized that my first impressions were wrong; the ancient ages of species are scientific determinations rather than scholarly conjectures. However, I have found in recent conversations that Christians remain skeptical of old ages and the evolutionary time scale. For this reason, I wanted the videocast to address the process of fossil dating (what the methods are and why they are accurate) while focusing on cases where hominid fossils were discovered and dated using these very methods. My hope is that Believers would be informed about the evidence for human evolution and its scientific grounding.

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

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

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

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

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

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

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

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

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

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

Along the side of our patio in front of our family garden, I grow grapes. I was inspired to grow them from the tradition of my mother's homeland in Cyprus, where grapes, olives, figs and lemons adorn the patios of each house. I was challenged to grow them well by the words of Jesus in John 15: "I am the vine, you are the branches, I will prune you to produce much fruit." Pruning is the secret to successful grapes, but that's another story.

The point is that in tending that grape arbor and our family garden, and exploring the beautiful landscapes we are blessed with in Virginia, my wife Elizabeth and I, along with our three daughters, are in communion with the Creator and Sustainer of heaven and earth. That may sound like a lofty statement, but for me, nature, His created order, is where I find Him most personally. I have known and recognized this since I was a boy.

Though born in Richmond, I was raised in Portsmouth, Virginia, where my father and I would fish along the Elizabeth River and the Chesapeake Bay. With my friends, I hunted in the Great Dismal Swamp. My father grew up on my Grandpa's farm in Tennessee near Bristol and he took our family back there often. My grandfather was one of those vanishing breeds of men who had fidelity and love for the land. He was dependent on the land for his food and a few cash crops for income. He was intimately tied to the rhythms of the seasons and his work in the fields.

My grandfather and my aunts and uncles looked at this work as a partnership with the Lord. They taught me how to care for the land, as well as the names of plants that grew in the forests and along the streams that surrounded their farms. They also taught me skills that made me appreciate their way of life. Through these early experiences, I became fascinated with an essential question: What makes nature tick? I also developed an interest in the spiritual relationship between God and His creation. And so the journey began.

I took up the study of biology at Virginia Tech focusing on stream ecology, and then worked as a field biologist surveying rivers throughout the Southeast. Eventually, I returned to graduate school to study forest ecology in the Shenandoah National Park. My faith in the biblical account of creation was challenged by professors who taught evolution as the mode of creation of living things.

This challenge I brushed aside until I began teaching biology at a community college in Clifton Forge. The words in the textbooks and the words of Genesis took on new meaning. Did they contradict each other? Could all forms of life really evolve by chance? Weren't we created in His image? My students questioned me about this conflict and I started a search for the answers.

For several years I wrestled with these questions as an intellectual exercise. I began to make progress only when I started answering with my heart along with my head, aided by that other gift received from my parents, trust in the power of prayer. Looking back, this doubt and questioning, this need to have all the answers, made my faith real exactly as it taught me that I don't need to have all the answers: that is where faith comes in.

I do know with certainty that God created the heavens and the earth, and manages and sustains His creation even today. I cannot know with certainty how He did it with such precision and beauty. How God created is still a mystery that science, by its methods, tries to discover and cannot fully explain, and one that the Bible is mostly silent on.

To me, there should be no contradiction between science and the Bible. In the beginning, God was there and science cannot speak to that. It is by faith that I know that God created the world not by chance, but for his purposes and glory. The precision of natural order and its beauty have always focused me on the Creator, just as Paul states in Romans that all creation bears witness to God. The more I study nature and natural sciences, the more it drives me back to God who made all things.

In time, I was hired by The Nature Conservancy in Richmond as the ecologist and director of a new biological inventory for Virginia. Then another faith question came. Why did the Church not speak to the Christian practice of stewardship as it relates to creation? Why did many in my profession worship the creation and not the Creator?

I stumbled upon the work of Wendell Berry, who has since become one of my favorite authors. In a short essay he wrote in 1988 entitled God and Country, he said we must deal with the true meaning of Genesis 1:28 where God told Adam and Eve to "be fruitful and multiply and replenish the earth and subdue it." He was right. Berry noted that many people use the words "dominion" and "subdue" as "unconditional permission to use the world as they please." I came to realize, like many, that such an interpretation is contradicted by the rest of the Bible.

The ecological teaching of the Bible is clear. God made the world and it pleased Him. It is His and He loves it. He has never given up title to it. He wants us to take excellent care of it. In Genesis we see it in His instructions to Adam and Eve in the Garden; in Leviticus 20, we see it in the Sabbath year and the Jubilee—laws governing land use, land rest and God's ownership of the land; in Psalm 24 David affirms "the earth is the Lord's and everything in it"; Jesus, in Matthew 6, tells us not to worry, for if God cares for the birds and plants, he'll also care for you; and in Romans 8:19, Paul says the creation eagerly awaits freedom when right relationships will be restored.

Biblical ecology is really a moral understanding of what God expects of us in relation to the natural world, but also in relation to the other people with whom we share it. This kind of stewardship has only been recently talked about in the Church. It means careful management, not destruction and abuse. It is infinitely practical because a healthy planet is in our best interest (we depend on its fruitfulness, after all), but biblical stewardship is also an act of loving our neighbors as ourselves, of loving even our children and grandchildren, by leaving them a decent place to live.

Psalm 8 lays out a mystery that, with the rest of Scripture in mind, invites a response in action as well as praise: "When I consider the heavens, the work of your fingers, the moon and stars you have ordained, what is man that you are mindful of him?" After more than 20 years with The Nature Conservancy in Richmond, Elizabeth and I have made a home for our family and have a church home, as well—all places in which we can respond to that mystery by bearing fruit. And though my answering the call to use my talents and time in each of those realms branches in many directions, it is always rooted in my awe of God, who created and sustains the universe and seeks a relationship with us. It is a call I live out in my vocation of protecting and restoring the lands and waters in Virginia, and a call our family lives out in our garden, in our frequent excursions in the outdoors, our worship of the Lord in church and at home, and, yes, even in growing grapes.

It didn’t seem right to deposit such a gift unreflectively into our bank account, allowing it to be swallowed up anonymously into our daily expense fund. My wife Sarah and I talked about a symbolic way we might use the money to honor John’s mark of grace on both of our lives. We very quickly settled on our decision: an SLR camera with a fine telephoto lens.

Many people remember John Stott for his books and preaching, but fewer remember him for his love of creation, his ornithological passion, and his knack for bird photography. On the very first day of my job working as his study assistant, I found on my desk a brand new set of binoculars and a copy of “Birds of Europe,” by Lars Johnson (the definitive guide). No study assistant was to work for John unless we shared in his love for birds, or at least could ably feign it. I soon discovered how seriously he took this avocation. In London he would stop whatever meeting we might be rushing off to in order to catch a look at a passing Kestrel. At his writing cottage in Southwest Wales we would begin every Sunday morning at Pickleridge Pools to see the Loons and Cormorants. Wherever we traveled, whether Uganda, India or Hungary, we would always schedule an extra few days to visit the local bird life with the accompaniment of a local expert.

But I also discovered that his love for birds was an extension of his love for creation and for its Creator. Uncle John took seriously the Psalmist’s words, “Great are the works of the Lord, studied by all who delight in them” (Ps 111:2). Taking “the works of the Lord” to include both God’s work of creation and redemption, he would often say that nature study and Bible study must go hand in hand. He was ahead of his time in calling Christians to have a more robust doctrine of and appreciation for Creation, and he viewed having at least one pursuit in the realm of natural history as an outflow of Christian discipleship. Indeed, it is striking that in his very last book, The Radical Disciple, in which he reflects on “some neglected aspects of our calling,” he includes “Creation Care” among Christian responsibilities like Christlikeness and Dependence.¹ And as remarkable as his accomplishments were in authoring such influential books as Basic Christianity and The Cross of Christ, it was his much less well known book The Birds Our Teachers,² which includes over 150 of his own photographs, that he would most often pull out to show visiting guests.

Some criticized John for his theistic evolutionary position and even his appreciation for Darwin, who John viewed as a man genuinely conflicted with how his discoveries could be integrated with his personal Christian faith. But Stott saw no contradiction between his own commitment to the authority of Scripture and his openness to God’s use of evolution in His creative process. He was of course unequivocal in his assertion that “One cannot be a Christian and not believe in creation.”³ Yet believing that Genesis 1 speaks more to the “why” rather than the “how” of creation, John also affirmed, “Those Christians who believe in evolution…mean that the huge variety of animal and vegetable forms can best be accounted for not by the independent creation of each, but by a gradual process of ‘descent with modification’, whether or not Darwin’s ‘natural selection’ is the best explanation of its mechanisms.”⁴ If anything, for John the possibility of God’s implementation of the evolutionary process was a striking example of the way God does not simply create but is also actively involved in sustaining and ordering His world.

So on the date of John’s birthday, April 27, we used his gift and bought our new camera. Laying it out on the table, I realized I needed a spacious and protective carrying case to hold the various lenses and equipment. I climbed up into the attic and retrieved John’s old camera bag, which he passed on to me after he had his second embolism and could no longer see well enough to take photographs. As I opened it up and examined the various lenses and mounts inside, now too old to adapt to any of the modern equipment, I realized I was holding in my hands the tools of one man’s passion and an expression of his love for his triune creator God. Deeply moved, I picked up my own camera, a new tool for my own stewardship of created life, and headed outside.

Notes

1. John Stott, The Radical Disciple (IVP, 2010).
2. John Stott, The Birds Our Teachers: Biblical Lessons from a lifelong bird-watcher (Angus Hudson, 1999).
3. Ibid.
4. John Stott, People Our Teachers (Angus Hudson, 2002), 110.

Jennifer Wiseman’s 2009 white-paper explained how a renewed engagement with science can enrich the church’s life of worship. Part 1 of our series taken from that paper discussed stumbling blocks to such a renewal. Part 2 began to describe how the Creation itself reflects the nature of God by displaying his power, creativity, beauty, patience, and faithfulness, all tied up in his character of love. This series concludes by connecting the knowledge of the world we get through scientific investigation with humanity’s Biblical mandate to exercise stewardship of God’s Creation.

Science can inform us of what we need to do, as stewards of God’s Creation.

Humanity faces tremendous moral dilemmas today, and science has relevance to most of them. As followers of Christ, we understand that our lives are entrusted to us for a short time, and that we will give an account for the things we do. So as stewards of our lives, and as disciples entrusted to build God’s Kingdom on Earth, it is essential to have knowledge and wisdom to shape the impact of our lives. Are we polluting the environment by our lifestyles? Clear studies of the relationship of how we live and the environmental impact on others are vital for God’s people. What about service? A well-intended project to provide irrigation or livestock for one needy people group may well end up polluting and destroying an ecosystem downstream.

Scientific understanding can foster wisdom for the best choices of lifestyles and service. And informed Christians can lead the pack in helping “science to inform science” when it comes to difficult ethical dilemmas. For example, farming systems that intensively confine animals may offer a promise from agricultural science of more food production to feed more people. But informed Christians can rightly cry foul, because the sciences of animal behavior and medicine clearly show that such confinement is inhumane and thwarts even minimal natural social and physical needs of animals, and environmental science shows that pollutants from such “factory farms” are devastating. The Biblical mandate for compassion for both people and animals is violated. Thus by combining compassion and prayer with broad scientific understanding, wisdom and clearer discernment will equip the Church for effective discipleship and social leadership.

There may be strong differences of opinion, between equally committed believers, as to the right use of science and technology. Should we genetically modify plants and animals, to provide a more abundant food supply? Should we design sophisticated weapons that can unintentionally destroy innocent lives? Should we use medical technology to prolong life at all costs? Such challenging issues can be an exercise in teaching God’s people how to be informed, how to articulate a viewpoint, and how to weigh respectfully the opinions and concerns of others, without necessarily condemning alternative points of view. In this way the Church can also set an example to the nation and the world of how healthy, respectful dialogue can foster productive progress in addressing difficult public issues. But how important are these issues, if the return of Christ is eminent? This is a realm of theological understanding that can affect whether some churches consider stewardship of technology and environmental protection as an important mandate of God, or even relevant to the future, if in fact there may be no long-term future of the present Earth. This requires careful teaching on the balance between embracing Godly stewardship principles with the intent to bless the world now and for many, many generations to come, while at the same time becoming spiritually ready to join the Lord however soon that may take place.

There is yet another realm of Christian discipleship in science, and that is simply the joy of exploration for its own sake, or rather, as a means of discovering and sharing what God has done. Sharing the wonders of Creation, as scientific discovery reveals them, is a great service to others.

(Earthrise: our beautiful, fragile planet, as seen from lunar orbit. Credit: NASA/Johnson Space Center)

Since I am an astronomer studying distant star-forming regions, and I work for our nation’s space exploration agency, I am sometimes asked by citizens of the public why we should spend any time or money on studies of outer space while there is so much human suffering on Earth: shouldn’t we solve the world’s problems first, before we spend money and effort exploring the oceans or the forests or distant galaxies? I have seen good people get very angry over what can appear to be completely unethical priorities; for instance should we send a probe to study Saturn when we could instead feed hungry children here on Earth? These dilemmas will always be present, and they are not simple. But I believe that God has called us to do BOTH: that is, to serve the poor and the suffering, AND to explore and study his Cosmos. In fact, it is those moments of great discovery and exploration, such as the first moon landing, or the Voyager images of Jupiter’s moons, or the historic first images from the Arctic explorers, that lift the human spirit and give us pause to contemplate the larger context and meaning of our lives. I have found kindred spirits, excited to learn about space, in both the western academic world and amongst the youngsters in impoverished, developing nations. Curiosity and wonder bring us together. We get a Biblical glimpse of this in Genesis, when God asks Adam to name all the animals. The text gives the sense of God’s pleasure as Adam sees the wondrous variety of creatures, and descriptively names each one.

And how should Christians view science and scientists? Since science is a systematic search for truth, and Christians believe that all truth is God’s truth, then there should be true appreciation for these “messengers” who devote their lives to understanding the details of God’s creation and who share their discoveries of scientific truth. Of course as human beings, scientists are sinful and fallible like everyone else. But the portrayal of science and scientists in the church should be a positive one. In fact, historically a great many leading scientists have done their work as explicit service to God (e.g., Blaise Pascal and Johannes Kepler). It should be no different today. Our congregations should encourage young people to go into science, and to see this (and all noble careers) as service to God. Imagine the difference it could make to the whole world if Christians would lead the use of science in a path compelled by love, compassion, and service!

Vox Balaenae, or “Voice of the Whale,” was composed by American composer George Crumb (b. 1929) and was first performed by the New York Camerata in 1971. It was only four years before that, in 1967, that biologists Roger Payne and Scott McVay discovered that humpback whales “sing” and published recordings of the whales’ complex vocalizations, after which “whale song” quickly entered the popular consciousness and helped propel the “save the whales” environmental movement forward. (In 1970, Folk singer Judy Collins even put out a version of the traditional melody "Farewell To Tarwathie" over a background of recorded humpback whale songs.) For many, the fact that the massive creatures might share the human capacity and desire to engage in music as a social activity only made their wholesale destruction at our hands more egregious.

Though he was himself inspired by hearing those early whale song recordings, Crumb’s work does not utilize tapes of real whales or attempt merely to reproduce the effect in the context of an ordinary musical form. Instead, he asks three chamber musicians with modified and electrically amplified instruments (piano, flute and cello) to create sounds that evoke the entire natural history of the sea. The piano is played and strummed from inside the case and with a glass rod or plate on the strings, the cello part emphasizes a string’s abilities to produce high harmonic tones, and the flautist sings into her instrument as she plays. Many of these effects are intended to suggest natural sounds—as in the cello’s "seagull effect" (audible at 5:59 in the video linked blow), and the whale-like beginning cadenza by the flute—but not always in a direct way. In addition, all three players perform wearing half-masks, which, according to Crumb help “effac[e] the sense of human projection,” especially when they play under blue stage lighting as he envisioned. (Most of these features can be seen and heard in this April 2011 performance in Montreal by Philippe Prud'homme, piano; Stephane Tetreault, cello

; and Camille Lambert-Chan, flute, though it omits the blue stage lighting.)

In this multi-sensory impressionistic scene, the whales become representatives of a natural world that predates humanity, yet whose fate is inextricably bound up with the will of mankind. Indeed, the tension between the measured vastness of geologic time and the “Age of Man” is written into the score, as an opening prologue is followed by variations on the initial “Sea Theme” (beginning at 4:20), each named after geologic epochs: Archeozoic, Paleozoic, Mesozoic, and finally, the Cenozoic. It is in this last age—when mankind arrives on the scene—that the sometimes atonal and harsh combinations of sound reach a dissonant climax that the score indicates should be played as “dramatic, with a feeling of imminent destiny” (beginning at 11:26). Finally, the piece moves towards its conclusion with a haunting restatement and renewal of the Sea Theme (at just after 13:00), with the musicians gradually playing more and more quietly until ending with a pantomime, as if creating sounds beyond the limits of human hearing. Again, the sense of resolution in the music is named by Crumb in the score’s instructions to the players: “serene, pure, transfigured.”

So what do we make of this musical narrative and what Crumb seems to be saying about both whales (standing—or swimming—for the natural world) and humankind? Is it truly an anti-human statement, a “whales vs. people” image in response to environmental damage we were only really beginning to understand (via science) at the time the piece was written? There is certainly a skepticism here about human hubris, made explicit at the end of the prologue section by a “parody” of the opening phrase of Strauss’ Thus Spake Zarathustra (at 2:40). Contemporary listeners then and now will likely recognize that borrowed theme as the music from the film 2001: A Space Odyssey (1968), but before that it was a musical homage to Nietzsche’s view of ascendant Man. In this ironic re-use of Strauss’ work, Crumb seems to say that against the span of geologic time and a vast (musical) world previously unknown to human ears, our claims of knowledge and technological mastery seem laughable.

Yet there are several clues that that sort of reading misses the mark, or that it is, at best, incomplete—beginning with the experience of playing and hearing it in person. I first heard Vox Balaenae in about 2002 with my then 6-year-old son. It was played in a small hall (under blue lights) at our local art museum by the Quadrivium Players, a group that included my friend Mary Boodell on the flute. While the masks were surprising at first, they did, indeed, de-emphasize the personality of the players as individuals, while emphasizing the atmospheric, world-creating power of art-forms, especially music.

Rather than a symbolic effacement of the human presence in the world (in keeping with the anti-Nietzschian not above), the effect was to move away from the ritualized performative aspect of modern chamber music and bridge the divide between players and observers, creating a more participatory community. Because of the piece’s distinctive, impressionistic kind of narrativity, one isn’t so much as “carried away by” the music as submerged and suspended in the world created by it, and Boodell describes the effect (especially at the end of the piece) of feeling like the audience is holding it’s breath to hear the silences Crumb has written into the score.

But Boodell also recounts the story of being drawn into the conceptual frame of the piece in a very physical, way when she found herself alone in a swimming pool in the weeks leading up to a performance. Though hesitantly at first, she couldn’t help but wonder how the sounds she made in Vox Balaenae would sound underwater, and so went under in the pool to find out. While the image makes one smile and probably reminds most of us of similar, less technically-proficient underwater experiments of our own, it also suggests how the piece helps hearers make a connection in addition to that between player and listener—that between humanity and the rest of the natural world. If the unexpected flow and soundscape created by Crumb helps audience and players achieve the kind of connection music scholar Jeff Warren has elsewhere on this site discussed as “entrainment,” it is also an invitation to a similarly compassionate state with the rest of creation, based on the new-found knowledge that other creatures have complex, even musical relationships with each other, and that we are privileged to discover and begin to understand them.

Clearly, then, Crumb’s Vox Balaenae touches on scientific knowledge of the world both in its genesis in recordings of whale songs and its structure keyed to geologic, evolutionary ages. But does it have more to say to us here than that we should avoid killing whales because they sing? While we can recognize that the biblical call to have dominion over the earth guides us towards cultivation and care for its creatures and remember that Jesus exemplified such a shepherding role, we should also remember his priestly one, and ours. For just as he remains the High Priest of heaven, holding our prayers in the presence of the Father, we have similar joy in being between heaven and earth, “a little lower than the angels.” Thus we can hold up the great whales (and their songs) as monuments to the depth of God’s creative activity in and through nature—and even revel in our musical, creaturely fellowship with them—without denying the special place of humanity. On the contrary, we affirm that special place when we humble ourselves to listen, seek to understand the native tongues of creation, and then, through Christ, present its songs before the throne of the Almighty Creator and King.

Today's video is courtesy of filmmaker Ryan Pettey, director/editor of Satellite Pictures and features physicist Ard Louis.

In today's video, Oxford physicist Ard Louis discusses the famous debate between renowned evolutionary biologists Stephen Jay Gould and Simon Conway Morris. Gould believed (and wrote in his book Wonderful Life) that if the "tape" of evolution were rerun, the chance that anything like human intelligence would emerge is essentially zero. In other words, humanity is here through random accident. Gould pointed to the work of Morris and fellow scientists in their research of the Burgess Shale as evidence for this view.

However, Morris himself disagrees, pointing to what is called evolutionary convergence. As Morris notes, there are numerous examples of identical features evolving multiple times throughout the history of life independently. Morris believes that if the tape of life were replayed, we would see something like humans emerge. A Christian might say, it looks like we were planned.

Some Christians might find Simon Conway Morris' viewpoint, with its implicit teleology, more attractive. Others, perhaps motivated by a high view of providence, may find Gould's emphasis on contingency equally congenial to their faith. What do you think?

In our previous essay, we learned that a tree summarizing species relationships can be built using DNA information, and how we can use DNA as a “molecular clock” to date ancient events. Both of these methods have made specific predictions about the origin of whales. If evolution is true: whales are related to the even-toed hoofed mammals and should share common ancestors with them; transitional fossil forms dating from about 45 to 50 million years ago should be found which can be shown to be related to both the even-toed hoofed mammals and modern whales; whales are most closely related to modern hippos, and should share a common ancestor with them.

What other types of information might we be able to use to construct a phylogenetic tree (i.e. a family tree) of species relationships? It turns out that characteristics of body structure also can be used – for example, the presence or absence of certain bones, or the specific shapes of those bones. An advantage of using bony features is that they can be recovered from fossils, whereas DNA (with only certain limited exceptions) must come from living organisms.

We can also derive functional information from an examination of bony features. The various protrusions, bumps and knobs found on bones usually have important implications. For example, smooth rounded areas at the ends of bones allow them to fit together and move easily. The shapes of such surfaces determine which bone motions are “allowed” or “disallowed”. Consider, for example, the motion of the forearm against the upper arm at the elbow. This is a “hinge” joint, whose normal motion is defined by the shapes of the upper arm bone and one of the forearm bones, where they meet each other. You might normally exercise the action of this hinge joint when you pick up a cup of coffee, bring it to your mouth, then set it back down again. Let’s try to imagine another motion. For this exercise we first need to get our arm into the proper starting position. Place your arm at your side, bent at the elbow at a ninety degree angle, with your palm up. Now, while keeping your palm up, let’s attempt to move your arm only at the elbow (no shoulder motion – that’s cheating!). Now swing your forearm out to the side and attempt to end up with your fingers pointed directly away from your side. Most of you will not be able to do this. If you can, it’s because your shoulder is rotating in spite of yourself. This motion at the elbow is normally not allowed. Hence a careful analysis of bone shapes can allow us to infer how the bones were used. This in turn can assist us in the task of phylogenetic (evolutionary) classification of organisms. That is, we will have more confidence in the grouping together of animals in our tree diagram if corresponding bones are used functionally in the same way.

Therefore we would expect that we could use various bony features to help us examine the predictions generated by our previous look at different types of DNA data. Are there any bony features that are particularly relevant to the even-toed hoofed mammals? Well, it turns out that there are. These are mainly running animals, and there are several features of their ankle bones, which taken together define the “allowed” motions which make them efficient runners. If one takes the various ankle bones of a large group of mammals, examines them carefully to note their shapes, scores that information into a table, then uses a computer program to build a phylogenetic tree, it turns out that all the even-toed hoofed mammals are placed together. So far, so good. But what about whales? Well, now we have an obvious problem. Modern whales are very specialized, - they have flippers which correspond to the forelimbs, and they have almost no hind limbs! I say “almost” because they do have small pelvic bones, which are not attached to the rest of their skeletons. But they certainly have no ankles. This is where the fossils should come in – if evolution is true, we should expect to be able to identify transitional fossils which are ancestral to whales which contain the characteristic ankle bony features of the even-toed hoofed mammals.

Now let’s look at bony features from the whale perspective. We have already mentioned the almost complete loss of hind limbs, and the presence of forelimbs modified into flippers. In addition, as air breathers, whales have a blowhole at the top of their skull. And as powerful swimmers, which use a large tail fluke in vertical motions, whales have enormous sets of muscles which attach to enlarged projections from their vertebral column. So if evolution is true, we should begin to see fossil forms which manifest changes in bony features which correspond to the gradual accumulation of these whale-like characteristics. However, we still need more, because these various bony features all would be expected to occur in largely or exclusively aquatic forms. We might expect this to correspond to the later stages of a transition from terrestrial even-toed hoofed mammals. But what about the earlier stages? It would be very helpful if we had some “defining” characteristic of whales, similar to the ankle structure of even-toed hoofed mammals.

It turns out that the structure of the bones of the skull and ear apparatus of whales are highly modified to allow efficient hearing underwater. The mechanical aspects of efficiently receiving sound through water are somewhat different than receiving sound travelling through air. If evolution is true, we should expect to be able to find key transitional fossil forms with a progressive series of modifications of the skull and ear bones, features which would not be found in any other mammals.

Now that we know what we should expect to see, if evolution is true, let’s look at what has actually been found in the fossil record. Over the last fifteen years or so, a series of fossils, many of them discovered in the Indian subcontinent, have fulfilled nearly all of our predictions.^1,2 Let’s look at the figure below (Figure 1), reproduced from a recent popular book on evolution.³ This shows a series of fossils, arranged in approximate chronological order, with a modern whale at the top. How old are these fossil forms? The entire fossil progression illustrated occurs from a little over 50 million years ago to about 40 million years ago. So a remarkable alteration in general body form occurred in a little over 10 million years. This time frame agrees well with the previous prediction from the DNA “clock” that we discussed in our previous essay. Second, the general change in body shape corresponds to what we predicted in our discussion of whale bony features above. That is, there is a gradual elongation and streamlining, there is a modification of the forelimb into flippers and progressive reduction of the hindlimb, the nostrils for breathing move toward the top of the skull to form a blowhole (not obvious from the diagram), and the vertebrae develop enlarged projections to support the attachment of swimming muscles.

Figure 1: Skeletons and Body Forms of Modern Whales and Fossil Ancestors
The reconstructed skeletons (black) from modern whales (top) and various ancestral skeletal forms (series below) are in chronological order (from Pakicetus up). Indohyus is an extinct whale “cousin”. Relative body size, to scale, is indicated by the gray shapes at the right of each animal.

There is probably little question that the last fossil species in the figure (Durodon) is well on the way to becoming a modern whale. However, it might be argued by a skeptic that the earlier species (like Rhodocetus, Ambulocetus, or Pakicetus), despite the “cetus” (whale) part of their names, are not so obviously “whale-like” that they deserve to be considered as fossil whale ancestors. However, remember the characteristic whale skull modifications for hearing? It has been shown very clearly that throughout this series of fossil species, the various bony changes necessary to support efficient hearing in water were being acquired in a stepwise fashion. Organisms earlier in the sequence had skeletal characteristics consistent with them being able to hear well in both air (using the “classic” mammalian hearing apparatus), and newly acquired changes to also allow better hearing in water. Later organisms in the sequence become increasingly specialized for hearing in water only.⁴

What of the earliest fossil shown in this diagram –Pakicetus? Careful examination shows that it has the features we would predict for an early whale ancestor. It has the ankle bone characteristics of the even-toed hoofed mammals (in fact these features are also found in several of the later fossil forms as well, ensuring their continuity). This confirms one of the predictions made by the DNA evidence we discussed earlier. Furthermore, it has some of the modifications of the skull bones necessary for more efficient underwater hearing, which were previously documented only for modern whales and their later (more obvious) ancestors.⁴ These features are also shared with the “whale cousin” Indohyus.⁵ Preservation of more of the skeleton of this latter species has allowed detailed analysis indicating characteristics likely shared with whale ancestors. Indohyus was probably a wading animal, which spent much of its time in the water. It appears to have fed mostly on land, so it is suggested that resort to the water was made to escape predators.⁵

Finally, we need to look back at the last prediction from our previous DNA evidence, namely that modern whales are most closely related to hippos. If evolution is true, we should expect to find fossil forms linking these two modern groups. This has proven to be a tougher nut to crack, mainly because the ancestral whales first appear about 50 million years ago in what is now south Asia, and the hippo family first appears about 15 million years ago, in Africa. The most recent tree diagram, produced by using a combination of skeletal features and DNA data, still supports this family connection, as shown by the following figure (Figure 2).⁶

Figure 2: Phylogenetic Tree Showing the Relationship of Modern Whales to Living and Extinct Even-Toed Hoofed Mammals
This tree is based on both bony features and DNA data. The organisms presented in blue are semi-aquatic or aquatic forms. Organisms shown in green are terrestrial even-toed hoofed mammals (Artiodactyls). In black is shown a member of the odd-toed hoofed mammals. In red is an extinct fossil ancestor group. (This figure is adapted from Fig 1a in Reference 6).

The blue lines in the diagram show species in which the skeleton is specially thickened, and the bone structure more dense. This is an adaptation which allows wading animals (like modern hippos and the fossil Indohyus) to be good “bottom-walkers” (it prevents them from floating due to lighter body tissues), and allows fully marine organisms (like modern whales) to have “neutral buoyancy” (so they don’t always tend to pop up to the water surface, like a cork). There has also been progress in clarifying the relationships between fossil ancestors of hippos and those of modern whales. A recent study of hippo evolution, based only on skeletal characteristics, has conclusively shown that the hippo family are descended from an extinct group of fossil Artiodactyls, known to go back more than 40 million years, and whose fossils are from southern Asia. Furthermore, this study produced a phylogenetic tree predicting that this extinct hippo ancestor group also shared a common ancestor with the fossil whales.⁷ Thus the investigation of hippo origins is independently leading us back toward the origin of whales. However, in this study the statistical support for predicted common ancestor of the ancient hippo group and the ancient whale group is not as strong as scientists would like to consider this “case closed”. What is necessary is more fossils, of the appropriate age in order to complete the story of hippo evolution. We still need that to fill in the details of the predicted relationship of hippos to modern whales.

Thus the “Whales’ Tale” is not yet complete. It is a story of scientific discovery in progress. As we finish, let’s briefly summarize what we have found out. Different types of DNA evidence agree that modern whales are most closely related to the even-toed hoofed mammals, despite the obvious great changes in limb anatomy of the modern whales. This prediction has been amply confirmed by the fossil record. The DNA sequence evidence predicted a time frame during which critical early events in evolution of whale ancestors should occur. This prediction has also been amply confirmed. Finally, DNA evidence predicts that modern whales are most closely related to hippos. There is some fossil evidence supporting a predicted common ancestor, but more data is needed. A final caution to possible sceptics – this state of “unfinished business” is precisely how the scientific process works. There is no “crisis”. There is no indication that evolution is not true. There is simply the ongoing work of mapping out of various lines of evidence. A scientific conclusion is considered well supported if “all roads lead to Rome”. In the case of whale evolution it might be prudent to say that the evidence has not quite converged in Rome yet, but that we are now in the suburbs. That is precisely what makes science interesting and fun. Stay tuned!

The next blog in this series can be found here.

References:

1: Thewissen J.G.M., Williams E.M., Roe L.J. and Hussain S.T. 2001. Skeletons of terrestrial cetaceans and the relationship of whales to artiodactyls. Nature. 413: 277-281.

2: Gingerich P.D., ul Haq M., Zalmout I.S., Khan I.H., Malkani M.S. 2001. Origin of Whales from Early Artiodactyls: Hands and Feet of Eocene Protocetidae from Pakistan. Science. 293:2239-2242.

3: Coyne, J.A. 2009. Why Evolution is True. Viking Penguin, New York. Pg 50.

4: Numella S., Thewissen J.G.M., Bajpai S.,Hussain T., Kumar K. 2007. Sound Transmission in Archaic and Modern Whales: Anatomical Adaptations for Underwater Hearing. The Anatomical Record. 290:716-733.

5: Thewissen J.G.M., Cooper L.N., Clementz M.T., Bajpai S., Tiwari B.N. 2007. Whales originated from aquatic artiodactyls in the Eocene epoch of India. Nature. 450:1190-1194.

6: Geisler J.H. and Theodor J.M. 2009. Hippopotamus and whale phylogeny. Nature. 458:E1-E4.

7: Boisserie J.-R., Lihoreau F., Brunet M. 2005. The position of Hippopotamidae within Cetartiodactyla. Proceedings of the National Academy of Sciences U.S.A. 102(5):1537-1541.

In the rest of the series, we will look closely at the evolutionary explanation for the blueprint. That explanation postulates that tetrapod limbs arose during a particular era in life's history, and that they arose as modifications of the fins of fish. And the evolutionary explanation isn't just an interesting idea. It's a comprehensive explanation – it helps us to understand bones, fossils, genes, chemical signaling systems. It provides a coherent framework for understanding why limbs are the way they are, and how they got that way.

Comparing the anatomy of tetrapod vertebrates and fish

The idea that tetrapods arose from fish is not new; E.D. Cope proposed in 1892 that tetrapods descended from lobe-finned fish. (Modern lobe-finned fishes include coelacanths and lungfish, and comprise one of two divisions of the bony fishes. The other division, the ray-finned fishes, includes most familiar kinds of fish.) In the early days, biologists inferred ancestral relationships between species largely through comparative anatomy and embryology: they would carefully classify organisms according to their structure (including their structure during development) and look for relationships that generated nested hierarchies. A simple nested hierarchy goes something like this: 1) animals with backbones; 2) animals with backbones and limbs; and 3) animals with backbones, limbs, and hair. Animals in group 3 also belong to groups 1 and 2, while animals in group 2 also belong to group 1, and so the groups together define a nested hierarchy. Such studies alone could have led some scientists to infer an ancestral relationship between fish and tetrapods, and perhaps those studies did convince them. But then there were fossils of various types of fish and other vertebrates, many long extinct. That fossil record was relatively sketchy in 1892, but it nevertheless led Cope and others to conclude that certain fish had given rise to tetrapods at a particular time in natural history.

The fossil record shows a fish-to-tetrapod transition

Here are some basic findings from the fossil record that suggest a fish-to-tetrapod transition and that have been known for decades:

• Fish, including fish with bones, lived on the earth before tetrapods appeared. Specifically, fossils of bony fish first appear in rocks from about 420 million years ago.

• Tetrapods appear in the fossil record at a particular point in history and then persist and diversify in subsequent eons. Their arrival was long thought to have occurred about 365 million years ago, although some recent findings have challenged that hypothesis.

• Tetrapods that still had some fishy features were prowling the planet 365 million years ago.

• Lobe-finned fish that were starting to look more like tetrapods were eating other fish about 385 million years ago.

Even many decades ago, there were hints that something interesting happened between 400 million years ago and 365 million years ago. Let's take a close look at the ancient animals that suggest the fish-to-tetrapod transition.

Ancient animals

The most primitive known tetrapods for which we have skeletal remains lived 365 million years ago. They were undeniably tetrapods, but there was definitely something fishy about them. (Heh heh.) One of the most famous of these creatures is Acanthostega, discovered in 1987 by British paleontologist Jennifer Clack and pictured below. Acanthostega is a card-carrying tetrapod, with fingers and toes. But it has a fish tail, with fin rays. Another well-known primitive tetrapod is Ichthyostega, which lived around the same time as Acanthostega. Like Acanthostega, it is a true tetrapod, but has several odd fish-like structural features. For example, its skull is more fish-like than that of Acanthostega. In summary, both Acanthostega and Ichthyostega already used the limb blueprint, even though both also had some fish-like anatomical characteristics. Their presence 365 million years ago shows that tetrapods must be at least that old, and their mixture of anatomical features suggests that the transition happened not long before that.

And what about the lobe-finned fish that looked a bit tetrapod-ish? That animal is Panderichthys, described as “vaguely crocodile-shaped” with skeletal features that were tetrapod-like. Specifically, this ancient fish had tetrapod-like “shoulders,” and recent analysis found some finger-like bones at the ends of the fins. The creature also had a breathing hole on the top of its head. These fish lived around 385 million years ago.

The hunt for the earliest tetrapods

Taken together, these observations suggested that the fish-to-tetrapod transition occurred between 385 and 365 million years ago. Eager to see what that transition looked like, scientists began to look for 375 million-year-old rocks in which they might find animals at the beginning of tetrapod-hood. They wanted to catch evolution in the act.

Let's stop and think about this, because it's cool and because it's important to note the extent to which evolutionary biology is hypothesis-driven. Critics of evolution sometimes portray the theory as an untestable historical conjecture, depicting it as fundamentally different from experimental science in the lab. But the hunt for the earliest tetrapods was an effort to test a hypothesis that had generated a prediction. Based on the hypothesis that lobe-finned fish were ancestors of tetrapods, scientists predicted that intermediate animals, “fishapods,” would be found in the gap between Panderichthys and Acanthostega. To evaluate the prediction, all they needed to do was find some suitable 375 million-year-old rocks.

Neil Shubin describes that search in the first chapter of Your Inner Fish. He and his colleagues found suitable rocks in the islands of the Arctic: the right age, nicely exposed (by erosion), and representative of the kind of environment that their quarry would frequent – freshwater streams. They made their biggest discovery on their last trip (“a do-or-die situation”) in 2004. That discovery was Tiktaalik roseae, the “fishapod.”

The “fishapod”

Tiktaalik roseae is one of the most extraordinary fossil intermediates ever described, and its public debut in 2006 was front-page news. An artist's conception of the animal is pictured below.

There are several aspects of the anatomy of Tiktaalik that earn it the title “fishapod.” Like a good fish, it had scales and webbed fins. Like a tetrapod (more specifically, like a crocodile), it had a flat head, with eyes on the top of the head, and it had a neck. But what about those fins? Or are they limbs? Remarkably, the answer seems to be, “both.”

The fins of Tiktaalik were part fish fin, part tetrapod limb. On the outside, they looked like fins, with webbing. On the inside, though, these fins were clearly tetrapod-like. Amazingly, the fins of Tiktaalik were built using a primitive version of the limb blueprint: one bone, two bones, blobs, digits. As Shubin writes in Your Inner Fish, “We had a fish with a wrist.” (The Tiktaalik roseae web site at the University of Chicago is a great source for images and more information.)

Let's address three questions about Tiktaalik that might have occurred to you. First, why might animals like Tiktaalik have developed tetrapod-like fins? Shubin and his colleagues suggest that these limb-like fins may have been useful for doing “push-ups” in the shallow water. (Like Panderichthys, Tiktaalik had a breathing hole on top of its head and was clearly adapted for living and moving in shallow water.) Second, is Tiktaalik an ancestor of all tetrapods? No, not necessarily. What Tiktaalik shows us is that animals were developing tetrapod features in the context of fish bodies, and Tiktaalik shows us the context (shallow water) in which this likely occurred. But that doesn't mean that our lineage arose from Tiktaalik itself. Finally, is Tiktaalik now the oldest tetrapod? No, apparently not. For one thing, Tiktaalik is truly transitional, and probably therefore not worthy of full tetrapod membership. But more notably, data published in 2010 show that tetrapods are a lot older than was thought at the time of Tiktaalik's discovery. The new findings show footprints that are unmistakably those of a tetrapod, in rocks about 395 million years old. Surprisingly, then, tetrapods were already on their way long before Neil Shubin's specimen lived. Tiktaalik is truly a fish/tetrapod intermediate, which was living at the same time as animals that were fully tetrapods. A simple story of succession, in which intermediates disappear and are replaced by less intermediate types, seems to be an oversimplification.

In conclusion, the fossil record provides evidence that the fins of fish and the limbs of tetrapods are related by ancestry: limbs seem to be modified versions of fins. What other evidence supports this proposal? In the next post, we will turn to developmental biology, and explore the meaning of the term 'homology.'

Further reading:

Neil Shubin (2009) Your Inner Fish: A Journey Into the 3.5-Billion-Year History of the Human Body. New York: Vintage Books.

Carl Zimmer (2006) A Fin is a Limb is a Wing: How Evolution Fashioned its Masterworks. Online at NationalGeographic.com.

Tiktaalik roseae website at the University of Chicago.

Jennifer Clack's website at the University of Cambridge.

Images are from Wikipedia.

Though some may believe that moving the science/faith dialogue forward is best left to scientists, scholars, and theologians, we at BioLogos recognize that our pastors play an invaluable role in the conversation. Across the globe, pastors are helping their congregations work through difficult issues of science and faith with honesty, insight, and a gentle spirit. To this end we present an ongoing series recognizing sermons (and the pastors who give them) that are helping to promote the harmony of science and faith. Today's sermon comes from Rev. Tim Keller, pastor of Redeemer Presbyterian Church. Click above to hear an excerpt. Below, is a brief summary written by BioLogos editorial staff. The full sermon, which we highly recommend can be purchased from Redeemer’s sermon store. Finally, if you know a sermon or podcast related to science and faith that has especially spoken to you, please let us know.

Genesis 2:2-17 places an interesting emphasis on work—not only does God work to bring about all creation, but also, man is called to the task of caring for God’s world. Dr. Keller believes this passage provides an important assumption, a purposeful direction, a resulting burden, and a necessary provision concerning the work.

First, because God is described as working, one can conclude that work reflects a significant aspect of God’s character. Therefore, when humans perform various tasks, they are reflecting the image of God. If working does indeed reflect his image, Dr. Keller states, then there is an intrinsic dignity to manual labor no matter what the occupation. This concept reveals the goodness of ordinary life. Whether simply gardening to produce food or cleaning a space to produce order, people are meant to rejoice in the responsibilities that daily life brings.

Then, Dr. Keller explains that the duty of humankind to care for God’s garden reveals the aim of all work. In order to garden properly, one must meddle with the natural state of things to bring about fruitfulness and prosperity. This may include clearing the ground to expose it to sunlight or trimming back plants to stimulate growth. The gardener cannot simply standby like a “park ranger” and let things freely develop—he or she must creatively order the garden in such a way that all plants thrive. In the same way, all work involves, as Dr. Keller puts it, “rearranging the raw material of a particular domain [in order] to draw out its potential for the flourishing of everyone.” He strengthens his point by applying this definition to the work of writing music. Music, he says, is created when the raw material of sound is structured in such a way that it brings meaning to human life. Overall, God has given all people the ability to express creative energy in the service of others, and that is the intended goal of work.

Next, the Genesis text reveals the burden of work. When the curse of the Fall came upon Adam and Eve, death entered the world. According to Dr. Keller, this is more than just a physical death that came to humanity. He compares the human condition to the second law of thermodynamics (which states that the universe is becoming more disordered) in order to demonstrate that people are falling apart physically, culturally, spiritually, vocationally, etc. People are constantly caught in the tension between their efforts to accomplish tasks and the unstoppable force of death that causes all things to degrade. Furthermore, he says that one can neither have a cynical view nor a romantic view of work. A person must recognize the goodness of work, yet keep in mind that it is still difficult and laborious. Although each person has a specific vocation through which to serve the world, he or she cannot always fulfill this calling because he or she must work to survive as well. This is the very heart of the frustration and burden of humanity’s calling to work in this fallen world.

Finally, in the midst of this struggle and tension, God has given humans this provision: rest. Genesis 2:3(NASB) puts forth the statement that, “…God blessed the seventh day and sanctified it, because in it He rested from all His work which God had created and made.” The Bible shows that this rest has been given as a free gift to all people, and it is not a provision that needs to be earned. According to Dr. Keller, this gift is the rest of peace and the rest of hope. It is the rest of peace because Christ has offered his love that assures believers in their significance. People no longer have to bear the burden that somehow their performance in their job or career determines their value as a human being. Likewise, it is the rest of hope because believers will one day have the ability to realize their dreams—an invention, a painting, a novel—when God makes the new heavens and the new earth. Therefore, a Christian need not be dismayed by the broken dreams in their heart during this lifetime, for one day, those things too will be accomplished. Now, through Jesus Christ, all can enter into the deep peace that their soul so desires and find true rest in work.

ADDENDUM: Please note, although we do invite your comments as we explore the theological richness of God's word in the sermon series, the comments will be restricted to Christians who are genuinely seeking to enter into a deeper and more meaningful relationship with God. Those who are not Christians but are seriously seeking to explore the Christian faith as a possibility for their own lives are also very welcome to raise questions and make comments. However, this will not be a place to belittle Christianity. We ask that our atheist friends respect our purpose here. We realize that you think Christianity is irrational and we are willing to engage the profound rationality of our faith, but this is not the place to discuss that with you.

A week ago, two of my sons and I got to spend several hours as part of a group looking for red cockaded woodpeckers at The Nature Conservancy (TNC) in Virginia’s Piney Grove Preserve near Wakefield, Virginia. Invited by State Director Michael Lipford and introduced to the bird and its habitat by TNC biologists and land stewards Brian van Eerd and Bobby Clontz, we were hoping to see the endangered birds at the northernmost limit of their present range, and to help count and identify individuals as they returned to their roosting trees for the night. But while we came on account of the woodpeckers—and protecting and encouraging their local population was the initial aim of assembling the contiguous tracts of pine forest that make up Piney Grove Preserve—it quickly became clear to us that the ongoing project of restoration was not about a single species, but an interconnected system.

As I wrote in a previous post, one assumption shared within the BioLogos community is that the natural world as revealed through scientific investigation provides signposts that point us to the Creator. Sometimes this means attending to the symbolism of specific creatures like the coelacanth or the red cockaded woodpecker (or RCW, as it’s sometimes called) in terms of qualities of God or the individual believer, but in other cases it means looking carefully not just at individual kinds but at the synergy between plants, animals and the land itself—looking at an ecology, in other words. Such a view can also heighten our appreciation of the ideal the Scriptures set forth for the whole human community, modeled first and foremost by the Church. Thus, while the red cockaded woodpecker is the “marquis species” in the restored pine savanna, understanding how the bird is integrated with many other kinds of living things (and even forces of nature) is suggestive of the interrelation between God’s providence and grace, and our own call to cultivate His world.

With that in mind, let me briefly suggest three of the elements in the pine savanna ecology that Christians may take as prompts for meditation on life in Christ: first, the pine trees in which the woodpeckers nest; second, the birds’ cooperative social structure; and third, the fire that enables both to thrive.

Alone of North American woodpeckers, the RCW carves out its home in the hearts of mature, living pine trees, generally at least eighty years old. It is on account of this habitat requirement that they became endangered by human appetite for pulpwood in the twentieth century, as a shift in logging practices to meet a changed demand meant that few mature trees were left standing. It was easier and more profitable to clear-cut swaths of young trees for paper than to grow old trees for timber. As our Conservancy guides and other sources attest, it is not just the size and age of the trees (making soft heartwood more likely) that is of benefit to the birds, but the fact that they are still living and producing sap.

Black rat snakes are a principal predator of creatures nesting in tree cavities, as the snakes are adept at climbing even the fairly limb-free lower reaches of pines. Red cockaded woodpeckers not only carve their brooding and roosting cavities into the trees, but in response to this danger also peck into the sapwood above and around their nests, causing a flow of the sticky pinesap to coat the area around the holes. These sap-flows form a physical and chemical barrier to the snakes, and give trees in which the woodpeckers nest a distinctively pale, candle-like look from the ground. Peering at a tree “grayed” by the birds that live within it, I could not help but consider that the tree offered sanctuary to the very creatures that wounded it, and granted them a sacrificial shelter exactly by spilling its life-blood.

The red cockaded woodpecker’s cooperative social structure is the second aspect of its life in the pines that offers an image worth consideration by Christians. These are not solitary birds, but ones that build their homes in clusters with several roosting trees for the non-breeding members of the group arrayed around a central tree that serves as home for the breeding pair and the chicks. The birds in the cluster are typically related, but there is considerable diversity in how the relationships between the birds plays out over time in terms of which birds become part of the breeding pair each year, how long the helper birds remain in that role and how they move off to form new clusters of their own. But all the birds in a given cluster contribute to cavity excavation and help provide food for the growing chicks.

While we can certainly take a more or less direct lesson in sociability and community interdependence from the woodpeckers, what is perhaps more instructive about this arrangement in terms of the science/faith dialogue is not its novelty, but that, any more, it is an example of what contemporary evolutionary biologists expect to find. As biologists gain increasing knowledge of the way the natural world operates as much by cooperation and interdependence as by a vulgar “survival of the fittest” model, evolution can be recognized as a tool by which some of the human values God has ordained for His people (including self-sacrifice, as above) are written into the rest of creation, as well.

Finally, a few words about fire. One of the principle duties of the Nature Conservancy’s Bobby Clontz at Piney Grove is to burn the woods, for the ecosystem that he and others in pine savanna settings across the Southeast are trying to restore depends on fire to maintain its distinctive park-like appearance and its specific diversity of species, both in the canopy and on the forest floor. While restoration of the original and especially fire-friendly longleaf pine is a slow process, even the now-dominant loblolly pine is safe from the smaller fires that result from regular burning of the under-story and, when mature, provide the same sort of safe haven for woodpeckers and all manner of other creatures.

Similarly, many of the native grasses that carpeted Southern forests two centuries ago also depend on fire not only to set seed and reproduce, but to keep down the bushy, mid-story plants that compete for sun and space and provide abundant fuel for larger, more destructive fires that reach into the crowns of the trees. Without fire there is no hope of recovery for the red cockaded woodpecker, because without fire the complex community of the forest cannot be restored, much less maintained. In this ecology, then, fire is not principally a force of destruction, but rather an indispensable source of renewal.

If the task here is to take note of signposts to the Lord that He has provided in the natural world, it is especially appropriate that we end by speaking of fire, as this is the Sunday on which the Church celebrates Pentecost, when the Spirit was bestowed upon Jesus’ disciples in the outward form of tongues of flame. Certainly that particular fire is no less critical to the health and life of the church than regular “controlled burns” are within the forest, but it may also be worth pointing out that in both the forest and the church, fire has often been pointed to principally as something to be feared—a harbinger and means of “the end”— rather than as a constant source of refinement and new beginnings.

As we consider the complex web of interrelations in the pine savanna, and how careful stewardship is bringing restoration not just to the red cockaded woodpecker but to the whole living community of which it is only the best known example, may God grant by the fire of his Spirit a similar revival within the church, for the blessing and renewal of the whole human community.