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.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Transcript

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

In our previous BioLogos podcast, we looked at the question of transitional fossils, and how the transitional species story strongly supports evolutionary theory. In this podcast, we look at genetic evidence for evolution. The discovery of DNA has revolutionized our understanding of common descent, particularly in the past few decades. Mutated genes spread through populations over generations, leading to the change we know as evolution. Amazingly, deeper study of DNA lines up with Darwin's initial observations of the larger natural world. While it would take weeks to highlight all the genetic evidence for evolution, today we focus on a few specific examples: the similarity of genomes for related species, psuedogenes, and genetic markers left by retroviruses.

For more, be sure to read Dennis Venema's series "Signature in the Psuedogenes" and "Understanding Evolution".

From the AAAS/Science Magazine Podcast (August 26, 2011). Posted with permission from AAAS.

These are mind-boggling times for a geneticist many years into his career. As a graduate student attending a conference at the University of California, Berkeley almost forty years ago, I remember watching with bated breath while another young graduate student, Nancy Maizels of Harvard, presented the DNA sequence of the lactose operator. Using amazing technology, she and Walter Gilbert had unraveled a little stretch of 24 units of code.

We were in awe—absolute awe—partly because the sequence was beautiful (it exhibited perfect twofold bilateral symmetry) and partly because we were incredulous that anyone could have done it—24 bases of DNA! A secret that had been locked inside of cells for millions of years was there on the screen in front of us. For a biologist, this was better than going to the moon. Twenty-four bases of the 4,600,000 bases in E. coli had been sequenced: one small step for a molecular biologist, but one giant leap for humankind!

It was Berkeley. It was 1973. Biology, we thought, had reached its zenith. The possibility of someday sequencing the other 4,600,000 bases of the E. coli genome or, heaven forbid, the 3,500,000,000 bases in the human genome, was like picturing the construction of a rocket ship that would take you to the outer reaches of the universe. No one dared dream of it.

I remember the February day in a San Francisco hotel in 2001 when Francis Collins, wearing a business suit (there were no business suits at Berkeley in 1973), showed his analysis of the just-completed first draft, not of another 24 base segment, but of the entire 3.5 billion bases in the human genome. Craig Venter, wearing a tuxedo (there were no tuxedos either), did the same the next night. We were dazzled with the two successive presentations. Indeed as the second evening came to a conclusion, it seemed like we had been on a trip—this time not to the moon, but now to the other side of the universe…and back.

Genetics had changed. No longer in a Berkeley classroom with shorts, sandals, long hair, and chalk board, we were now on the other side of the Bay in a fancy hotel in downtown San Francisco, where champagne corks were popping. Molecular biology had made the big time. Still, the simple awe of having unraveled the beauty of the molecule’s secrets was not dimmed by the hype or the glitz. The majesty of the molecule spoke for itself and I felt just like I had 28 years earlier.

What, I wondered, would be next? What could top a trip to the other side of the universe and back? We all had dreams, but no one dared dream of what actually happened.

Even as that excitement was wooing us all, the next unbelievable trip was already unknowingly underway. Svante Paabo and colleagues were working out the techniques to extract and sequence DNA from 30,000(+) year old Neanderthal bones. Never, in my wildest imagination in 2001, would I have pictured the possibility of obtaining enough nuclear DNA from our long extinct relatives to sequence their genome too. But now, ten years later we have a draft (1.3 fold coverage) of the DNA instructions for building the body of a Neanderthal.

It doesn’t stop there though. The molecule keeps revealing its secrets. No sooner had I caught my breath from reading the details of the Neanderthal sequence, when the biggest shock of all was released last December. Found in a Siberian cave were the fossilized bones of a single finger of a female hominin (human relative) who lived between 30,000 and 50,000 years ago. Paabo’s group was able to isolate enough high quality DNA from that one pinky finger to sequence her entire genome. (Listen to the fascinating discussion of the discovery in the accompanying audio.) We now have a better draft (1.7 coverage) of the DNA from the bones of one “pinky” finger than we do of the all of the fossilized Neanderthal remains put together.

Prior to analyzing her genome, investigators expected to find that either she was a human being like us, or she was a Neanderthal. What they found, however, no one was prepared for. No one! The DNA in that finger was not ours, nor was it Neanderthal. This single finger was from a different hominin altogether. Now it is clear that we had relatives—known as the Denisovans—roaming the earth in the recent past who were as different from us as Neanderthals were. There would likely have been at least hundreds of thousands of these individuals that lived on Earth from the time of their inception to the time of their extinction. Yet all we have identified so far is one finger, two molar teeth (found in the same cave, but from a different individual) and a piece of a knuckle bone. It was their genome, not a fossil, which has told us of their existence. Without that we would not have known.

And I thought biology had gone to the moon when it revealed the 24 base sequence of the lactose operator! Now we have billions of bases sequenced and a draft of the instruction plans for building three different hominins, all of whom lived on this Earth at the same time, as recently as 30,000 years ago.

There are many ramifications of this discovery. First, we are in the unprecedented—and until now unimagined situation—of having the entire genome sequence of an organism for which we have virtually no fossil material. (One pinky, two molars and a part of a knuckle bone do not a full-fledged fossil make).

At BioLogos, we have said many times that we would expect to find significant gaps in the fossil record (see here for example). We understand the basis for the gaps. For one thing, fossilization is an exceedingly rare event, but there are other well-understood reasons as well. Paleontologists have scoured the world looking for hominin fossils. They are big and easy to spot should they be present in the area being searched, but the fossil record of these newest hominins was silent until recently. What ought that to tell us? How long will it take us to grasp that gaps in the fossil record are not surprising? The surprising thing is that we have as good a record of past events as we do. It’s that which should amaze us, not the absences.

Second, now that we have drafts of the instructions for building all three body types, we can determine how similar they are and when they would have last shared a common ancestor. Based on genetic analysis, the average gene difference points back to a common ancestor of all three groups who lived about 800,000 years ago.

The Neanderthal and the Denisovan are a little more closely related to each other than they are to modern humans. In their case, analysis of average gene difference suggests that they last shared a common ancestor about 400,000 years ago—though they are still very different from each other.

To give you a feeling for how similar and different they are from one another, consider human/chimpanzee differences. It’s been about 6,000,000 years since we had a common ancestor. On the other hand, our family tree is identical to that of the Denisovans and Neanderthals until about 800,000 years ago. We’ve only been diverging separately for a little over 10 percent of the time since the last common ancestor of chimps and humans. Of course, when one considers how different chimps are from humans, even ten percent of that for the human/Neanderthal or human/Denisovan comparisons is large. They were very different from us and it will be extremely interesting to analyze the differences gene by gene as the analysis continues in the coming years.

Third, we need to acknowledge that as the genetic and paleontological data keeps piling up, it is most important that the Church become engaged in thinking about its meaning. It is clear now that we can trace our lineage—in some cases gene by gene— with amazing precision. These are cousins of ours: the Neanderthals, Denisovans, and almost certainly others who occupied the Earth at the same time, some perhaps as recently as 17,000 years ago.

BioLogos exists to help Christians think carefully about the ramifications of these new data in light of long-standing traditional ways of viewing human creation. We have some re-thinking to do, but it can be done and will be done within the context of a Christian faith that is fully orthodox and thoroughly evangelical. Any time we draw closer to truth, to God’s truth, we have nothing to fear. There is still much to learn, but we can look back at what we have learned with awe—absolute awe.

I’m not at a Berkeley conference anymore, and I’m not in a cork-popping San Francisco hotel either. For me, however, this stage is the most thrilling of all because it takes us deeper—far deeper—than we could have ever imagined. Addressing the theological and philosophical questions that lie ahead will be rewarding to work through and will take us far outside the natural universe into the realm of the New Jerusalem—the supernatural world of heaven itself. This is God’s truth we are coming to understand. We must not leave this territory, which reveals so much about human nature, to the exploration of those who don’t believe there is a New Jerusalem. We as Christians ought to be at the forefront in thinking about the meaning of these new data and not turning our backs just because we find it so surprising (and to many, unsettling). As we begin an all-fulfilling journey across this new frontier together, I am confident we’ll go in the presence of God. The DNA molecule is God’s creation, after all, and the secrets it reveals to us are his truths, not ours.

The above audio, from the August 26th Science Magazine podcast, is a very engaging discussion of the science that has led to our current state of knowledge. We greatly appreciate the American Association of the Advancement of Science (AAAS) for granting us permission to post it here. Ann Gibbons, the interviewee, is a journalist at Science Magazine. For more about her work see http://www.anngibbons.com/bio/bio.shtml

Many scientists think that evolution is a directionless process, one in which humans are merely an accidental byproduct. In a recent episode of the award-winning radio program “To the Best of Our Knowledge” (produced by Wisconsin Public Radio, and reposted above, with permission), however, esteemed paleontologist Simon Conway Morris of Cambridge University explains a different view of evolution. Conway Morris has catalogued plentiful examples of evolutionary convergence, in which different organisms arrive at the same function through different evolutionary pathways, including the trait of intelligence. He examines the ability of the octopus to gaze, learn and play, and compares it to the intelligent behaviors of dolphins and the tool making ability of certain crows. Given enough time and resources, he says, every ecological niche will be filled up by some kind of life form. One of these niches is that for highly intelligent life, a niche occupied by us, Homo sapiens. If the tape was rewound and evolution started over from scratch, Conway Morris says, the evolutionary details would be different, but the end result would be similar: a species characterized by intelligence and complex civilization.

While several esteemed scientists, including atheist Richard Dawkins, and Brown University cell biologist, Kenneth Miller, agree with Simon Conway Morris, most (according to Dawkins) do not accept that evolution can have this sort of directionality. Sean Carroll, leading evolutionary biologist and Vice-President of the Howard Hughes Medical Institute, says that animals merely “exploit what’s available,” with no necessary end. Little, he believes, is inevitable. “With a few other rolls of the dice”, he says, evolution would have resulted in a significantly different assortment of organisms. Noted philosopher of science, Daniel Dennett, agrees with Carroll. Just as the origin and wide-spread diversity of creatures like marsupials (mammals with a pouch) was not inevitable, he says, so the evolution of intelligent human-like beings was not inevitable either. Dennett goes on to say:

The idea that this whole great universe was in some sense designed or intended for us strikes me as just bizarrely self-involved (chuckles)—one of the most stunningly narcissistic visions that I’ve ever encountered. It seems unlikely, don’t you think?

In complete contrast Conway Morris says:

The universe from a theistic viewpoint, from a Christian viewpoint, is utterly contingent. It needn’t exist at all, more particularly it could be anything which God so chose. Science is an open-ended adventure; we don’t know where it’s going to end. People who think religion is simply a set of answers to keep you comfortable are, I’m afraid, sadly mistaken—it is an open-ended adventure. We don’t know, really, what the nature of the universe is. We don’t know why we have our moral, ethical, intellectual and poetic capacities. I know they come from an evolutionary basis, I have no quarrel with that. But so far as I’m concerned, we are going on to completely new territory and my view would be that in fact the religious instincts and the religious teachings actually tell us something real about the world. They’re not simply fairy stories.

So is the near-certainty of human life front-loaded from the beginning? Was it predetermined from the Big Bang that human beings would eventually arise? Was it predetermined that God’s natural activity—that activity which upholds the universe and maintains all that is within it—would be sufficient for the eventual development of humans? Alternatively, was supernatural activity required for the creation of the human body? Does the Bible dictate one way or the other? Is it somehow less God’s creation if it took place through God’s natural activity? Is it somehow more God’s creation if supernatural activity was required? These are questions for theologians. Science is taking us up to edge as Conway Morris brilliantly shows. There, we meet the theologians, and there, we begin the journey’s next phase.

I encourage you to listen to the above recording. The deeper we explore creation, the more we see and appreciate its beauty. So also, and even more significant, the deeper we embed ourselves in God's written and Living Word, the more confident we become of “Romans 8:26-39”. We are loved. More than we can possibly imagine, we are deeply embedded in the love of God. This, truly, is "Life's Solution."

]]> Thu, 11 Aug 11 02:15:51 -0700 Darrel Falk http://biologos.org/essays/science-as-an-instrument-of-worship?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication http://biologos.org/essays/science-as-an-instrument-of-worship?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication NASA astronomer Jennifer Wiseman asserts that studying creation can show us the nature of God; science can inform us of what we need to do as stewards of God’s creation; understanding the natural world gives us a deeper knowledge of Jesus Christ; and science can give us a better understanding of ourselves. This essay was presented at the November 2009 Theology of Celebration Workshop. Mon, 02 May 11 19:10:34 -0700 Jennifer Wiseman http://biologos.org/essays/christian-geologists-on-noahs-flood-biblical-and-scientific-shortcomings-of?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication http://biologos.org/essays/christian-geologists-on-noahs-flood-biblical-and-scientific-shortcomings-of?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication Geologists Davidson and Wolgemuth address the widely promulgated notion that the Flood can account for the earth’s complex geology, and that all genuine Christians should accept this viewpoint. Mon, 25 Apr 11 17:09:05 -0700 Gregg Davidson and Ken Wolgemuth http://biologos.org/essays/why-dembskis-design-inference-doesnt-work?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication http://biologos.org/essays/why-dembskis-design-inference-doesnt-work?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication Mathematics professor James Bradley looks at the design argument presented in William Dembski's book The Design Inference and offers his criticisms on the accuracy of the model. The Design Inference and offers his criticisms on the accuracy of the model.]]> Mon, 25 Apr 11 16:47:42 -0700 James Bradley http://biologos.org/essays/intelligent-design-thomas-aquinas-and-the-ubiquity-of-final-causes?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication http://biologos.org/essays/intelligent-design-thomas-aquinas-and-the-ubiquity-of-final-causes?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication In this paper, Baylor philosophy professor Francis Beckwith distinguishes between Intelligent Design (ID) and Thomistic Design (TD). Fri, 22 Apr 11 17:20:27 -0700 Francis Beckwith http://biologos.org/essays/design-in-nature?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication http://biologos.org/essays/design-in-nature?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication In this paper, adapted from an article from Science & Christian Belief, Dr. Oliver R. Barclay compares and contrasts the biblical view of design in nature with modern design arguments. Science & Christian Belief, Dr. Oliver R. Barclay compares and contrasts the biblical view of design in nature with modern design arguments.]]> Fri, 22 Apr 11 17:17:14 -0700 Oliver R. Barclay http://biologos.org/blog/series/john-polkinghorne-on-natural-theology?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication http://biologos.org/blog/series/john-polkinghorne-on-natural-theology?utm_source=RSS_Feed&utm_medium=RSS&utm_campaign=RSS_Syndication Polkinghorne discusses the origins and aims of natural theology in this series. It does not offer truth, but rather a “best explanation” for the world, answering primarily meta-questions. Two such questions asked by Polkinghorne are, “Why is science possible at all?” and “What makes the universe so special?” To explore the answers, he looks at the ability of human minds to penetrate mysteries of the natural world as well as the fine-tuning of the universe necessary to produce the fruitfulness of life.

As part of the H. Orton Wiley Lecture series in Theology on the campus of Point Loma Nazarene University, Reverend Dr. John Polkinghorne inspired students and faculty alike in thinking about the interaction between science and the Christian faith. The first lecture, entitled, Natural Theology, was delivered on November 15th, 2010. The entire MP3 is available for download here.

In Part 2 of this series, Dr. Polkinghorne looked at the first of two meta-questions. In today’s post, he looks at the second of these meta-questions: “Why is the universe so special?”

We provide a written transcript of the talk to make it easier to mull over Dr. Polkinghorne’s ideas while you listen.

Fine-tuning and the “Fruitful Universe”

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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