By Richard Hollis (aka Ritchie)

Two rather interesting and welcome stories have hit the headlines in as many days that I thought I'd bring up here.

The first bit of news is that from next week, for the first time, an abortion advisory service is to screen an advert on TV in Britain. Centred around the slogan 'Are you late?' the commercial will advertise the services of the organisation Marie Stopes, which offers advice on sexual health matters, including abortion services.

Abortion has been legal in Britain since the Abortion Act of 1967, but Marie Stopes is adamant that there is a need to promote sexual health issues. "Clearly there are hundreds of thousands of women who want and need sexual health information and advice, and access to services." (source)

Unsurprisingly this has been met by a backlash from pro-life organisations who insist that the advert will be promoting abortion. The campaign Pro-Life had this to say: "The purpose of an abortion commercial is clearly to 'sell' abortion and it will not provide full information about foetal development, the abortion procedure itself, the health risks which abortion poses for women, let alone the alternatives to abortion." (source) While religious organisations are more hysterical. "These adverts will just mean more women will end up on the abortion industry conveyor belt," said the Christian Medical Fellowship. "Getting an abortion is not like buying soap powder, and it shouldn’t be advertised on TV," said the Christian Institute. (source)

I for one, however, am delighted at the news. This is more than about advertising a particular helpline - it is about introducing the topic of sexual health into the public domain and breaking through this taboo topic. It is about power and control. It is about shame and repression.

While the media is absolutely awash with images of a superhuman ideal of female perfection, marketing everything from cosmetics to operations to endow youth and beauty, actual frank discussion about sexual health is still woefully sparse. If organisations which promote impartial advice on such matters are not to be advertised, then how are women to know about them? How are they to know the options if faced with an unplanned pregnancy?

Presumably pro-life groups would prefer it if women never knew about such organisations - and never needed to. Women should never have sex unless they intend to get pregnant and then should turn into good little breeding machines.

Granted I haven't actually SEEN the advert. For all I know it might be the tasteless promotion of cheerful abortion Pro-Life and the Christian Institute envisage. But I doubt it. I am confident this is nothing more than an impartial advisory service offering their services. And its presence encourages open debate on a sensitive subject. I applaud this and certainly intend to tune in to watch its first screening (Monday 24th May, Channel 4, 22.10, to those who want to do the same).

The second news item is that US scientists, led by Dr Craig Venter has developed a cell controlled entirely by synthetic DNA. He and his team had already succeeded in transplanting a genome from one bacterium into another, and in creating a synthetic bacterial genome, but this is the first time they have combined the two already remarkable achievements. (source)

The potential of this breakthrough is massive. This could be the start of gigantic leaps in the fields of medicine, biology, and even climate change. It is also another milestone reached by dedicated scientists doing empirical research into unlocking the mysteries of life itself.

As the religious right never tire of reminding us, we don't know exactly how life started or works. We do not have all the answers. Yet we are making progress. Scientific investigation based on methodological naturalism and materialism is yielding results. Answers are being uncovered. And those who care about human progress should rejoice that we are one step nearer to an answer which will never be found just by sitting around in slack-jawed bewilderment at how complex everything is and concluding magic fills in the gaps in our knowledge.

The rather tepid reaction to scientific progress was demonstrated well by the Vatican's response to the news. While, to their credit, Catholic church officials praised the pioneering scientists, they tempered this with words of caution. "Pretending to be God and parroting his power of creation is an enormous risk that can plunge men into a barbarity," warned one. "In the wrong hands, today's development can lead tomorrow to a devastating leap in the dark," cautioned another. (source)

So it's, 'Well done on getting us this far, but think twice before you take us any further', is it? How encouraging.

While outraged accusations of 'playing God' and visions of the imminent zombie apocalypse inevitably accompany the experiment, I am left wondering if there has ever been a significant scientific achievement that was NOT met with such cries? Were we 'playing God' when we performed the first organ transplant? When we discovered antibiotics? When we drew up the periodic table? When we discovered how to make fire?

Yes, new technology always needs to be handled with caution. But that is no reason to be afraid of it. Science puts the 'ability' in 'responsability' (if you spell it wrong).

The Case for a Creator, Chapter 9

Chapter 9 is ostensibly about the origin of biological information, but what it's really about is the origin of life. We've discussed this in part in an earlier chapter, but Meyer has some other objections to raise.

First up, Strobel raises the question of the "prebiotic soup" - the dilute broth of organic molecules that's believed to have existed in the Earth's oceans before the origin of life, a fitting stage for many kinds of complex chemical reactions. This is a plausible environment for abiogenesis to take place, so Meyer tries to sow some doubt:

"I hear scientists talk a lot about this prebiotic soup," I said. "How much evidence is there that it actually existed?"

"That's a very interesting issue," he replied. "The answer is there isn't any evidence... If this prebiotic soup had really existed... it would have been rich in amino acids. Therefore, there would have been a lot of nitrogen, because amino acids are nitrogenous. So when we examine the earliest sediments of the Earth, we should find large deposits of nitrogen-rich minerals... Those deposits have never been located." [p.227]

There's no footnote for this, and I find it a puzzling and implausible argument. Earth today contains billions of tons of organic molecules locked up in life. But the Earth is a closed system. Aside from negligible contributions by comets and meteorites, the atoms on this planet today are the same ones that were here when it was first formed. As I mentioned in an earlier post, we know from Miller-Urey-type experiments that organic molecules like amino acids readily form in the presence of a source of energy. How could there not have been a prebiotic soup? What does Meyer imagine all those molecules were doing prior to the origin of life? (Then again, as I pointed out in chapter 4, Meyer appears to be a believer in the young-earth mythology - so maybe the alternative he's really trying to push is the Garden of Eden.)

Meyer also fails to qualify his mention of "earliest sediments". The earliest sediments, if by that he means sedimentary rocks of the same age as the origin of life, do not exist: erosion and plate tectonics tend to destroy and recycle the very oldest rocks. Most of the oldest surviving rocks that we possess are zircons, tiny mineral grains that form in igneous and metamorphic rocks. Zircons can be radiometrically dated, and some are known that are over 4 billion years old, but they don't offer any clues as to when life got started.

The oldest geologic evidence of life is significantly later. There are fossil stromatolites about 3.45 billion years old in rocks from the Warrawoona Group of Western Australia, which is the oldest clear evidence of living things. More controversially, there are rocks from Greenland about 3.85 billion years old that may contain "chemofossils". Living things concentrate the C-12 carbon isotope, rather than the slightly heavier C-13. These rocks show that same altered ratio, which could be a chemical marker left by early life. Evidence this subtle is still being debated by the scientific community, and given the extensive recycling of the Earth's oldest rocks, it's not reasonable to expect "large deposits" of nitrogen-rich minerals dating back to the origin of life to have survived.

Meyer has only one source to back up all of this, and it's a real laugh riot:

"In fact, Jim Brooks wrote in 1985 that 'the nitrogen content of early organic matter is relatively low - just .015 percent.' He said in Origins of Life: 'From this we can be reasonably certain that there never was any substantial amount of 'primitive soup' on Earth when pre-Cambrian sediments were formed; if such a soup ever existed it was only for a brief period of time.'" [p.227]

Strobel labels this an "astounding conclusion", but what he should be more astounded by is how far Meyer had to stretch to find a source for this claim. Wanting to verify this, I did a search for Jim Brooks' Origins of Life, only to find that it's long out of print according to several online booksellers. But more comical is that Strobel cites the publisher of this book as "Lion" - which I found out is Lion Hudson, which is, in fact, a Christian publishing house. A twenty-year-old, out-of-print book by a Christian publisher - that's the most reliable source that could be found to back up these assertions! Couldn't Meyer find even one actual scientific source to quote-mine?

Other posts in this series:

• Rebutting The Case for a Creator

The Case for a Creator, Chapter 8

In the previous installment, I discussed how creationists steer well clear of doing any real science. We can see another example of this in, ironically, the way Strobel falls all over himself lauding Michael Behe as a Real Scientist:

He has authored forty articles for such scientific journals as DNA Sequence, The Journal of Molecular Biology, Nucleic Acids Research, Biopolymers, Proceedings of the National Academy of Sciences USA, Biophysics, and Biochemistry... He is a member of the American Society for Biochemistry and Molecular Biology, the Society for Molecular Biology and Evolution, and other professional organizations. [p.196]

(Side note: Why is Behe a member of the Society for Molecular Biology and Evolution?)

But never mind that parentheses. Just take a look at Michael Behe's impressive scientific track record! See how many prestigious peer-reviewed journals he's published in! Just try to refute the ID-supporting scientific arguments of... but wait a minute. Strobel has swiftly stepped around a very obvious question. How much of that vaunted publication record actually supports the arguments of ID?

The answer, if you don't stop at Strobel's glossy superlatives and actually go on to look at the papers, is: not much. If you look at Behe's CV, you can see that most of his work is about technical aspects of DNA and protein structure (with scintillating titles such as, "Quantitative assessment of the noncovalent inhibition of sickle hemoglobin gelation by phenyl derivatives and other known agents"). And if you look a little more deeply, you'll notice an even more interesting fact: Behe's already modest scientific output nosedives in the early 1990s. Not by coincidence, I'm sure, his much-hyped Darwin's Black Box was first published in 1996. Perhaps that was when he found out that working the creationist lecture circuit was a much easier, and far more profitable, line of business. (There was one new paper by Behe in 2004 - the only exception to what's otherwise a decade-plus publication drought. We'll come to that in a later post.)

There may be another reason for this, and we'll see it in the first section of this chapter. Guided by Strobel, Behe begins the conversation by talking about how simple Charles Darwin and his contemporaries thought that cells were.

"In Darwin's day, scientists could see the cell under a microscope, but it looked like a little glob of Jello, with a dark spot as the nucleus... Electricity was a big deal back then, and some believed that all you had to do was to zap some gelatinous material and it would come alive. Most scientists speculated that the deeper they delved into the cell, the more simplicity they would find." [p.196-7]

This claim, which apparently originated with Behe, has become a touchstone of creationist literature. Many prominent ID advocates, all using each other as their only sources, have spread the claim far and wide that early Darwinists thought cells were extremely simple. The trouble for them is that this claim is utterly false. Darwin himself (who was a skilled microscopist), wrote about the "astounding complexity" implied by what he could see of cells' organization and behavior. For details, see this post by Wesley Elsberry, which also catalogues the sloppy anti-evolutionists repeating this falsehood.

I'm sure you've guessed Behe's motivation for making this false claim: so he can dramatically whisk the curtain back and proclaim (much to Darwinists' imagined horror) that no, those tiny little cells are really complicated!

"We've learned the cell is horrendously complicated, and that it's actually run by micromachines of the right shape, the right strength, and the right interactions." [p.197]

This is Behe's cue to launch into a description of some of the molecular processes that operate within the cell. I'll spare you pages of verbiage about mousetraps and highways and motors - ID advocates still love these cartoonishly simple, Paleyesque analogies - except to note that Strobel chimes in on cue, gasping theatrically at the "stupefying complexity" [p.209] of this processes that stand revealed.

All this buildup is just so Behe can get to his overall point, which can be summed up thusly: "Look how complicated this is! Look how many different parts it has and how well they have to work together! I just can't imagine any way this could have developed gradually through evolution, can you? Let's just give up, say it must have been intelligent design, and then go home."

Lest you think that I'm being unfair to Michael Behe, he actually says something like this in this book, and in very nearly these words. Here's how he puts it:

"Now, does this microscopic transportation system [Behe is speaking about the endoplasmic reticulum —Ebonmuse] sound like something that self-assembled by gradual modifications over the years? I don't see how it could have been. To me, it has all the earmarks of being designed." [p.209]

"I don't see how it could have been": this is the argument of intelligent-design advocates in a nutshell.

I do wonder if this way of thinking is partly responsible for creationists' near-total lack of scientific output, even those who were actual scientists before joining the ID movement. Their argument is based on treating the complexity of the living world as utterly intractable and inexplicable. Is it not likely that this attitude discourages them from trying to study it? When your theology teaches you that science is a futile pursuit, why even attempt to do science?

The error at the root of this complexity phobia is the belief that evolution is incapable of creating complex things. This is implied in Behe's arguments throughout this chapter, though it's never explicitly spelled out. But why should we believe this? Evolution has been running on this planet for billions of years. It's not at all surprising that, with so much time to accumulate beneficial mutations and acquire new genes, the end products that we see today would be very complex indeed. And those molecular systems that Behe is so awed by? Many of them are found in bacteria, which number in the trillions and have generation times measured in hours. If evolution were a contest, bacteria would be the undisputed champions. Is it any wonder that there's so much complexity down at the bottom?

Other posts in this series:

• Rebutting The Case for a Creator

A couple of noteworthy articles from this week that I didn't have time to write more about:

• To begin with, there's this excellent and in-depth profile of the FFRF's Dan Barker and Annie Laurie Gaylor, from a local alternative paper in Madison.

• Archaeologists have discovered a genuine burial shroud from the first century CE. Unlike the Shroud of Turin, its radiocarbon date fixes it to the correct time period; it also has a very different weave than the more famous Turin hoax.

• Churches in Malaysia are being attacked by Muslims, who are angry over a court ruling that struck down a government ban on the use of the word "Allah" by Christians. Perhaps we should get Nancy Graham Holm over there to explain to the Christians that it's their own fault they're getting firebombed, because they rudely persist in using a word of which Muslims are the rightful owners.

• A muckraking blogger named Failed Messiah exposes the scandals of the Orthodox Jewish world. (HT: New York Times).

• The Telegraph tells us that heroic behavior among animals is more common than previously thought. Who was it that said only human beings have a sense of morality?

• And finally, a story I may return to later: New York City mayor Michael Bloomberg has invited atheists to the city's annual interfaith breakfast for the first time ever. Bravo, sir! It feels good to be taken seriously by politicians for once.

This past summer, I was visiting the New York Botanical Gardens when serendipity struck: this beautiful little creature alighted on a stone railing around the edge of a pool, staying just long enough for me to snap this shot:

I think, though I'm not an expert, that this is a blue dasher, Pachydiplax longipennis.

I don't usually like close-up photos of insects - they have an eerie, alien feel that I find disturbing. (I admit it, I'm a mammal chauvinist.) But this one is one of the rare exceptions. Looking at it again, it's hard for me not to feel admiration for this sleek, graceful creature.

With its iridescent blue scales, its impossibly frail and transparent wings, its delicate jointed legs, it scarcely seems to belong to nature at all. It looks almost like a device, a tiny whirring clockwork machine made by some detail-obsessed jeweler - except, of course, that we humans haven't yet learned to make machines of such fine and precise workmanship, nor any that pack so many marvelous capabilities into such a small package.

So much of its head is taken up by those huge, gorgeous compound eyes, it seems it has scarcely any room for a brain to process the information they take in. Yet dragonflies have keen eyesight, and are blurringly fast and acrobatic fliers - and imagine how well-tuned their organs of balance must be, to control their pitch, roll and yaw in three-dimensional space at such speeds, a task that would overwhelm a human vestibular system. And though they seem so clumsy, so fragile - adult dragonflies can only fly, not walk, and their wings can't be folded in like a beetle's but must be held out at all times - on their own small scale, they are fearsome and effective predators. And of course, like all living things, dragonflies have one more astounding ability that human-designed devices can't match: they can make copies of themselves from the raw materials of their environment!

All in all, despite all our brains, we humans can't create anything nearly as clever, as intricate, as adaptable, or as beautiful as a dragonfly. But we shouldn't feel too bad: when it comes to forging machines, we've had barely a few hundred years of practice. Evolution has had hundreds of millions of years to refine its designs, to hone and sharpen them against the ruthless grindstone of natural selection. With that much of a head start, and with all the resources of a planet to use for trial and error, it's no wonder that even this blind algorithm produces results of a beauty and craftsmanship we can't match.

And yet, the stunning truth is that we ourselves are products of the same evolutionary process. Look at your hands, your arms, and imagine tens of millions of years of natural selection pushing and tugging on them like a sculptor kneading clay, slowly molding flesh and bone into new shapes. Imagine the skeins of DNA coiled in your cells, woven out of evolution like a tapestry from a loom. Imagine the unbroken chain of your ancestors stretching back into the misty recesses of time, each one only subtly different from the last - but even subtle changes add up, until you reach a point, untold millions of generations ago, where the ancestral lines of human and dragonfly merge into the same track.

This knowledge should fill us with awe. The fact of universal common descent via evolution means that I and this glittering blue dragonfly, no matter how distant the links, are related. When I snapped that picture, it was a family reunion, of sorts - and the admiration I felt for its intricacy and beauty is the same kind of admiration I'd feel for any talented relative whose glory reflects, even if only a little, on his siblings and cousins.

The human species is like a hiker who, having scaled a long and arduous path, can finally stop at a vantage point and look back on the journey he's taken. Looking out across the landscape, we can see our fellow travelers, each one taking a different course from all the rest, all of them spreading out from a single point of origin in the far distance. Why should we not feel a sense of kinship for all the other beings who are traversing life's winding, contingent paths along with us? And why should we not marvel all the more that our astonishing existence is not the result of deliberate planning, but of a glorious, messy, freewheeling cauldron of chance?

I haven't written about any new transitional fossils in a while, so it's a great pleasure for me to mention this one: a hominid skeleton nicknamed "Ardi", a specimen of Ardipithecus ramidus. This species was known from other fossil fragments, but Ardi is one of the oldest and most complete hominids found so far, and may give us the most insight yet into what the common ancestor of humans and chimpanzees looked like.

Image copyright 2009, Jay Matternes.

Ardi lived about 4.4 million years ago (by comparison, Lucy and her fellow australopithecines are about 3.4 million years old), in the Middle Awash region of modern-day Ethiopia. Today it's an arid badlands, but in that era, it was a lushly forested woodland, cool and wet but geologically active, with frequent volcanic episodes (a great boon to biologists, since volcanic rock and ash strata are easily dated with radiometric methods and give us good estimates of when a certain fossil lived). Primitive elephants, giraffes, horses, antelope, rhinos and monkeys are well-known from this area, as are other hominid specimens.

The fossil itself is believed to be a female. The bones were so poorly fossilized, according to the Science paper by Tim White and colleagues, that they would crumble if touched. The researchers painstakingly chipped them free of the rock they were encased in with dental picks, bamboo, and porcupine quills (!). From the fossil's discovery to its publication took nearly 15 years of preparation and study - but from all accounts, it was worth the wait.

In life, Ardi would have stood just under four feet tall and weighed about 110 pounds. The skull was small, about 325 cc, about the same size as a chimp's. Ardi's teeth suggest she was an omnivore, and from comparing other A. ramidus teeth and bones found in the region, White and his colleagues found little difference in tooth size or body size between male and female individuals. This suggests that their mating style was relatively peaceful, with little competition for mates (as compared to chimpanzees, who have massive canine teeth which are used to intimidate potential rivals) and possibly more stable pair-bonding and group cohesion.

Ardi's hands, feet and pelvis tell us a lot about how she got around. Hominids like Lucy show a mosaic of bipedal and arboreal adaptations - as Laelaps puts it, they "had their hands in the trees and their feet on the ground" - and Ardi shows a more primitive version of the same pattern, much as we'd expect from an ancestor of that age.

She stood and walked upright, though not as well as Lucy or as us, and her feet were becoming more rigid like ours, except that she also had an opposable big toe useful for grasping. Her arms were long enough to reach to her knees when standing upright, but her hands were not adapted for knuckle-walking. Nor did they have the specializations for climbing and hanging from trees that we see in modern apes. She still lived in the trees, but would have moved through them more slowly and carefully than chimps or orangutans, and was capable of descending to the ground and walking. This refutes the once-popular belief that bipedalism first developed when human ancestors left the forest for the savanna and adapted to stand upright so as to see over the grass - as shown by species like Ardi, bipedalism evolved before we left the trees.

Another popular but erroneous idea that Ardi refutes is that the common ancestor of humans and chimps looked basically like a chimp, and that humans have changed significantly while modern chimps are little different from our common ancestor. This is probably tied to the misconception of the "great chain of being" that sees humans as the highest or most advanced form of life on Earth. Ardi, who probably lived relatively near the time when our two lineages split, instead shows that both humans and chimpanzees have evolved and specialized since the time of our common ancestor, becoming adapted to two very different ways of life.

Other articles:

Ardipithecus: We Meet At Last. The Loom, 1 October 2009.

Tim D. White, Berhane Asfaw, Yonas Beyene, Yohannes Haile-Selassie, C. Owen Lovejoy, Gen Suwa, and Giday WoldeGabriel. "Ardipithecus ramidus and the Paleobiology of Early Hominids." Science, 2 October 2009: 64, 75-86. (full text online, requires free registration).

The Case for a Creator, Chapter 4

In the last section of his interview with Stephen Meyer, Lee Strobel brings up the dysteleological argument, asking how intelligent design can account for the faults and imperfections in the natural world that would seem to cast doubt on the wisdom or benevolence of the designer. He begins with a classic argument, the inverted retina. Quoting Ken Miller:

"We would have to wonder why an intelligent designer placed the neural wiring of the retina on the side facing the incoming light... This arrangement... produces a blind spot at the point where the wiring is pulled through the light-sensitive retina to produce the optic nerve that carries visual images to the brain." [p.86]

Meyer waves this off, claiming (without further explanation) that this arrangement is "a tradeoff that allows the eye to process the vast amount of oxygen it needs in vertebrates" [p.87], which Strobel accepts without qualm. He admits that this arrangement produces a blind spot, but "that's not a problem because people have two eyes and the two blind spots don't overlap". I'm sure the families of people killed in car accidents because they didn't see the other car in their blind spot will be relieved to hear that.

Although Meyer doesn't go into any more detail about what he means, I'm assuming it's the same argument as given here by Michael Denton. But even if one accepts the creationist argument that the retina needs extra blood supply, that still doesn't explain why there has to be a hole in it for those vessels to pass through. (It also doesn't explain why octopuses do just fine with a non-inverted retina and no blind spot - unless the designer liked them better than us.)

Moving on from this point, Meyer tries to ward off the dysteleology argument by claiming that all design has "inevitable tradeoffs and compromises". This is true, but misses the point. We're not faulting adaptations for being less than theoretically perfect, but for being demonstrably suboptimal, such that they could have been unequivocally improved by an intelligent designer without making any tradeoffs. The inverted retina is one. Another, possibly even better example is the human appendix, which in the absence of modern surgery results in about 1 in 15 people dying slowly in great pain from peritonitis. If this is the result of design, one shudders to consider the intelligence of the designer.

We move on to another classic evolutionary exaptation:

"For instance, Gould claimed the panda's thumb looks jerry-rigged and not designed. Well, experts on the panda say it's a pretty efficient way of scraping the bark off bamboo." [p.88]

Again, Meyer has obscured the argument here. It doesn't matter how efficient the panda's thumb is: the point that matters is what the panda's thumb is.

Like most vertebrates, human beings have five digits - in our case, four non-opposable fingers and one opposable finger, the thumb. Pandas have the same five digits, but they are all non-opposable. The panda's "thumb" is a sixth digit, a pseudo-finger created by enlarging and extending a wrist bone called the radial sesamoid.

The panda's thumb. On the left is the hand of a modern giant panda, Ailuropoda melanoleuca. Note the five digits and the enlarged radial sesamoid. On the right is the hand of an extinct carnivorous mammal, Simocyon batalleri, a possible panda ancestor (source).

The panda's thumb is not an example of dysteleology in the sense that the inverted retina is. It's an example of evolutionary tinkering - the haphazard, jury-rigged kind of adaptation that we see again and again in the natural world, what led Richard Dawkins to call evolution a "blind watchmaker". Because of the random nature of mutation, it's to be expected that evolution would sometimes solve the same problem in different ways. On the other hand, if there is an intelligent designer, why didn't he just give the panda four fingers and an opposable thumb, the way primates have?

The jury-rigged, ad hoc nature of adaptation is just what we would expect from evolution. ID, on the other hand has no explanation for this, other than postulating a capricious, whimsical designer who repeatedly reinvents the wheel rather than reusing his own solutions from other lineages. In other words, ID advocates have to assume a designer whose work looks like the product of evolution.

To close out the chapter, Meyer resorts to another all-purpose excuse to explain any examples of dysteleology he might have missed:

"The Bible says there has been decay or deterioration because evil entered the world and disrupted the original design... Based on the biblical account, we would expect to see both evidence of design in nature as well as evidence of deterioration or decay - which we do." [p.88]

In other words: everything good can be credited to God, everything bad can be blamed on sin (although it's not explained why human sin resulted in "deterioration or decay" among other species - this is something that Christian apologists since Milton have had difficulty with). One wonders if the appendix represents "deterioration or decay", and if so, from what. Did pre-Fall humans have an herbivore's cecum filled with cellulose-digesting bacteria? Did Adam and Eve browse on grass in Eden?

On that note, it's worth pointing out that this statement seemingly places Meyer in the camp of the young-earth creationists, those who believe in a literal Garden of Eden, a literal serpent tempter and a human race descended from just two people. If that's the kind of outright nonsense that Strobel is endorsing, his claim to be presenting the latest cutting-edge science goes up in smoke. We'll get more into this topic in the next chapter.

Other posts in this series:

• Rebutting The Case for a Creator

The Case for a Creator, Chapter 3

In the final section of chapter 3, Strobel and Wells turn to the evidence that creationists loathe above all else: the fossil hominids that make up the human family tree. Human ancestors are not only a clear, obvious transition that even a layperson can understand, they directly demonstrate that we ourselves are a product of evolution, thus striking at the desire to be separate, special creations that almost certainly motivates nearly all creationists.

I strongly suspect that creationism as a movement would never have arisen if scientists hadn't insisted on encompassing the human species in evolution's family tree. Whatever the creationists say, they don't really care about turtles or oak trees or earthworms. If scientists were willing to grant that human beings were special, unrelated to the rest of Earthlife, creationists would probably have been happy to concede that every other species came about from a process of mindless natural selection. But the evidence doesn't support a separate origin for humanity, and the idea that we might be one of those animals - a relative of slime molds and toadstools, of centipedes and cyanobacteria - enrages creationists, who can't bear to believe in a universe in which they are not the central and most important figure. In their quest to reclaim that sense of specialness, they would gladly obliterate the best theory ever devised to explain the true origins and diversity of life as we now see it.

And this leads us to the last section of Strobel's interview with Jonathan Wells. We begin with Java Man, who, according to his discoverer Eugene Dubois as quoted by Strobel, "represents a stage in the development of modern man from a smaller-brained ancestor" [p.61]. Strobel points out - for once, correctly - that the find consisted of a skullcap, a femur and some teeth, but that the femur and the teeth are now believed to belong to different species.

Nevertheless, Strobel writes as though Java Man is an isolated find, a single fossil fragment drifting in a void of uncertainty. As usual, the creationists have ignored the abundant corroboratory evidence. Java Man is just one specimen of a well-known hominid species, Homo erectus, that is known from many other specimens - including Sangiran 17, a far more complete skull that was also found on Java - and even more spectacularly, the Turkana Boy, a nearly complete skeleton of an approximately 12-year-old erectus boy found near Lake Turkana in Kenya. All these specimens, including Java Man, share the characteristics that make them unlike modern humans: a sloping forehead, heavy brow ridges, large jaw with no chin, and a braincase much smaller than ours (between 750 and 1100 cc, depending on age, while most modern sapiens have brains about 1350 cc).

What do the creationists think Homo erectus is? We never find out Strobel's viewpoint, since neither he nor Wells ever mentions these fossils. The closest he ever comes is asserting that Java Man is a "true member of the human family" [p.62]. That's actually correct, although it doesn't mean what Strobel thinks it does.

Aside from this brief discussion of Java Man, we hear nothing more about any specific fossil. Wells spends the rest of this brief section complaining about how artistic reconstruction of fossils is a speculative field [p.62] and quote-mining science writers who point out that we cannot reconstruct exact lines of descent from fossils - which is true, but Wells acts as if this means that every theory ever devised about human evolution is worthless. The lesson he takes away is not that we must be careful to only propose testable hypotheses supported by the evidence, but that "Darwinists assume the story of human life is an evolutionary one, and then they plug the fossils into a preexisting narrative where they seem to fit" [p.63], as if the fossils themselves had no meaning and could be used to support any conceivable hypothesis equally well.

I also want to highlight one particularly obnoxious bit of dishonesty. Here's Wells quoting science writer Henry McGee:

"In fact, he said that all the fossil evidence for human evolution 'between ten and five million years ago - several thousand generations of living creatures - can be fitted into a small box.'" [p.63]

It's true that the oldest fossil evidence of human evolution - the species nearest the branch point of humans and other apes - is fragmentary. But by definition, those species would be the least humanlike. What Wells neglects to mention is that all the most important fossil evidence showing how humans became human is younger than five million years! Australopithecus afarensis, and the other australopithecines, are between 4 and 3 million years old. Homo habilis is between 2.5 and 1.5 million years old. Homo erectus is between 2 million and half a million years old. We have multiple fossils for most of these species and others, far more than would fit in a "small box". Wells' sleazy tactics would be like a defense attorney getting a witness to admit that he saw nothing unusual between 5 and 6 PM, and triumphantly concluding his client was innocent - even though the crime took place at 7.

Again, what stands out about this section is how little time Strobel and Wells spend on discussing the actual fossils of human ancestors. We never hear about Turkana Boy. We never hear about Lucy or Homo habilis. What were these creatures? How does the intelligent-design worldview explain them? This is a question Wells steers well clear of, other than repeating postmodernist claims that any explanation is just as good as any other.

Now I'll do something that Strobel and Wells never do: show you the fossils so you can see them for yourself. Here's a table, with pictures, which lists some of the most important hominid specimens and shows what creationists think about each of them.

As you can see from the table, although all the creationists are adamant that every fossil is either fully human or fully ape, they can't agree which is which. (Java Man in particular is an almost even split, especially if you include Strobel and Wells' claiming that it's human.) This, of course, is exactly what we would expect if these fossils were genuinely transitional: being intermediate between two groups, they would resist unambiguous classification as one or the other. Ironically, the creationists themselves provide the best testimony of that.

Other posts in this series:

• Rebutting The Case for a Creator

The Case for a Creator, Chapter 3

Up until now, Jonathan Wells' critiques of evolution, although misguided, have been fairly sophisticated, touching on topics such as abiogenesis, the Cambrian explosion, and embryology. That's about to change. In this section, Wells and Strobel haul out the most breathtaking, shameless lie bandied about by creationists: that there are no such things as transitional fossils. This opening quote foreshadows the direction they're going:

I was under the impression that [Archaeopteryx] was featured in my books on evolution because it is just one example of many transitional links that have been found. But I was wrong. [p.56]

Strobel then quotes this jaw-dropping passage from Michael Denton:

[T]he universal experience of paleontology... [is that] while the rocks have continually yielded new and exciting and even bizarre forms of life... what they have never yielded is any of Darwin's myriads of transitional forms... The intermediates have remained as elusive as ever and their absence remains, a century later, one of the most striking characteristics of the fossil record. [p.56]

Even by creationist standards, this is a bald-faced and brazen lie. Not only do transitional fossil series exist, we have a strikingly large number of them, bridging most of the major evolutionary changes in life's history. But don't take my word for it, see the evidence for yourself.

There's the tetrapod transitional series - fossils documenting the evolutionary change from fish to four-legged land animals - whose crown jewel is Tiktaalik roseae. There's the therapsids, the fossils documenting the evolution of mammals from reptiles, which preserve in exquisite detail the evolution of the jaw. There's the well-known horse transitional series. We know much detail about the evolution of whales, including Ambulocetus, the so-called walking whale. And of course, there's the evidence creationists hate the most - fossil human ancestors - which we'll get to in due time.

But this section focuses on Archaeopteryx, a particularly striking example of evolutionary transition. This feathered dinosaur is far too well-known even for creationists to deny it exists, but Wells tries to fog the evidence by implying that it's not really transitional:

"Besides, we see strange animals around today, like the duck-billed platypus, which nobody considers transitional but which has characteristics of different classes." [p.57]

This is another example of the things Wells should already know. In fact, the platypus is transitional - albeit a kind of living transition.

The platypus belongs to a very rare group of mammals called monotremes. Although these animals have fur, give milk and show other mammalian traits, they have others that are more primitive, most notably the fact that they lay eggs. They also lack the well-developed nipples of mammals that their young can suck on; their milk oozes from glands on their chest, and the babies lick it up. But they also have advanced adaptations not shared by other mammals, like venomous spurs or the platypus' famous "bill" - which has nothing in common with the bills of ducks, but is actually an electrosensitive organ of exquisite sensitivity.

Living monotremes are found only in Australia and New Guinea, and this separation is a clue to their evolutionary history. The most likely explanation is that, during the Mesozoic era, the animals that would ultimately become mammals split into several branches. One branch became the placental mammals, which includes us. Another branch became the monotremes. Both groups inherited proto-mammalian features such as fur and milk from their common ancestor, while others, such as the bearing of live young, evolved in placentals after the branch point, while monotremes retained the ancestral egg-laying state. In this sense, and discounting its own unique adaptations, the platypus is a sort of living example of what our common ancestor might have looked like.

But, back to Archaeopteryx. As I said, even Wells can't deny it exists, but he does resort to lying about the nature of the species:

"But the archaeopteryx is a half-bird, half-reptile, right?"
"No, not even close," he insisted. "It's a bird with modern feathers... not part bird and part reptile." [p.57]

Image via.

Wells makes no attempt to justify this assertion, because it is patently false. Other than its feathers and a few other subtle characteristics, Archaeopteryx is actually much more like a dinosaur than it is like a bird. The Talk.Origins Archive's All About Archaeopteryx FAQ lists its reptilian features, which far outnumber the avian characteristics. (See also.)

And even besides this, what about the many other feathered dinosaurs, such as Sinornithosaurus and Microraptor? Over twenty genera of feathered theropods are known, most from China. Wells steers well clear of these, other than to mutter an accusation that they're probably all fakes [p.59]. We do, however, get a sermon on Archaeoraptor, which serves the same purpose as Haeckel's embryos - a convenient whipping boy for creationists which they use to distract attention from the real facts that support evolution.

Archaeoraptor was a chimera - a composite of bones from several different animals - most likely created by unscrupulous amateur fossil hunters. The fraud was detected almost immediately, within a matter of weeks, and was never published in peer-reviewed papers (source). In fact, the Archaeoraptor saga is an excellent example of how science is supposed to work. The only reason we're hearing anything about it is because one popular, non-peer-reviewed publication, National Geographic, exercised insufficient caution and ran with the story before scientists had authenticated it.

After lying about the existence of well-known scientific evidence and accusing paleontologists of mass fraud, Wells has one final card to play:

"...reptiles that are more bird-like in their skeletal structure... they find them millions of years after archaeopteryx! So here we have archaeopteryx, which is undeniably a bird, and yet the fossils that look most like the reptilian ancestors of birds occur tens of millions of years later in the fossil record." [p.57]

As I said earlier, Wells has an education in biology and should know better than to make these obviously deceptive claims. A real scientist would have known the explanation for this immediately and would not have tried to mislead readers by implying that this is unexpected or a problem for evolution.

Evolution rarely, if ever, works in a single, smooth trajectory of change - species A changes into species B, which changes into species C, and so on. Instead, what we usually see is a path of descent more like a densely branching bush: species A radiates into species B1, B2, B3... and so on. Most of these go extinct, but B2, say, speciates into C1, C2, and C3, and again, some of the daughter species go extinct and others diverge in their own ways. But species don't have fixed lifespans, and there's nothing to dictate how long a particular species will survive before it goes extinct. There may still be living species from the A or B generation existing side-by-side with far more advanced descendants. (Readers are referred, again, to the platypus for an example of how this can turn out.)

In the case of Archaeopteryx, that's just what happened. In the bird family tree, feathers were an early innovation, one that arose before most of the other features typical of modern birds, and Archaeopteryx was one of the earlier species to have them. (Remember, again, that it has far more reptilian than birdlike characteristics.) But other feathered reptiles, other lines of descent in the same family tree, spun off descendants of their own, and some of these had more of the features that, in retrospect, we classify as diagnostic of birds. In short, Archaeopteryx wasn't a direct ancestor of modern birds: it was an aunt or an uncle. But even if it's not on the direct line of descent, it's still a powerful and compelling example of transition in progress, one twig on the branching tree of life's history.

Other posts in this series:

• Rebutting The Case for a Creator

The Case for a Creator, Chapter 3

Strobel's discussion of embryonic similarities with Jonathan Wells leads into a broader discussion of homology, which deserves its own post.

I've been harder on Wells than I otherwise would because he, unlike the vast majority of creationists, has a legitimate degree in biology. It's impossible that he doesn't understand some of the things he claims not to understand, or that he doesn't know the actual scientific explanations for the questions he poses. That being the case, there's no explanation for many of the confusions or patently false claims he makes, other than that he's deliberately attempting to deceive lay readers. This post will point out some examples of that.

To get our definitions straight, homology is a detailed similarity of organization that is functionally unnecessary. The streamlined shapes of fish and dolphins are not homologous, because they can be explained by similar adaptive pressures acting on both species to increase their swimming speed. But the fact that both humans and dolphins have five finger bones (in dolphins, buried in their fins) is an example of homology, because no adaptive necessity that we know of would compel such a similarity of structure. In fact, nearly all mammals show this striking pattern, even though their limbs have been radically modified to serve purposes as different as swimming, burrowing and flying:

"Actually, these homologies were described and named by Darwin's predecessors - and they were not evolutionists." [p.52]

From the emphasis Wells puts on this statement, it seems we're meant to find it shocking. I don't know why he thinks we should be surprised that scientists who predated Darwin were not evolutionists. Is the argument here that if something was first noticed by non-evolutionists, it can't be used to support evolution? That would be a ridiculous distortion of how science works.

As with the similarities in vertebrate embryos, the homology among living creatures is an observation. Evolution is an explanation for that observation, and many others as well, which shows how a wide variety of observed facts can spring from the root of a single unifying principle. That's how science is meant to work. No one scientist "owns" an observation, nor are they the final judge of what theories it can be used to support, even if they're the one that discovered it.

Wells goes on to claim that homology can't be used as evidence for evolution unless we understand how it arises. This is a fair point, but the explanation is obvious, though he tries very hard to make it seem incomprehensible:

"A more common explanation nowadays is that the homologies come from similar genes. In other words, the reason two features are homologous in two different animals would be that they're programmed by similar genes in the embryo. But it turns out this doesn't work very well...
    There's a gene that's similar in mice, octopuses, and fruit flies. If you look at a mouse eye and an octopus eye, there's a superficial similarity, which is odd because nobody thinks their common ancestor had an eye like that. What's more striking is if you look at a fruit fly's eye - a compound eye with multiple facets - it's totally different. Yet all three of these eyes depend on the same or very similar gene.
    In fact, it's so similar that you can put the mouse gene into a fruit fly that's missing that gene and you can get the fruit fly to develop its eyes as it normally would." [p.53]

Wells claims that this is a deep mystery and an insurmountable difficulty for explaining homology, but it's neither.

In addition to creating proteins which do the hard work of building body parts, genes can also turn other genes on or off. Genes like the one Wells mentioned (its actual name is eyeless, because of the effect on development when it's knocked out) are master control switches. When activated, they set in motion an entire cascade of other genes. It's differences in those downstream genes that create the differences between mouse, octopus, and fly eyes, but the initial genetic switch that kicks off this program is very similar across species - so similar that, as Wells notes, the mouse eyeless gene can trigger the development of eyes in fruit flies.

This is the explanation for homology that Wells claims not to understand. When we see these homologies, what we're seeing is alterations of a developmental program. All mammals have inherited a toolbox of genes from their common ancestor which they use to do things common to all mammals, such as building limbs. In every mammal species, the same master control switches are there; the same genes building the same body parts are there. But the program has been altered by selective pressure - turning some genes on for longer, or suppressing others sooner - to change the limbs in ways that are adaptive for various different niches.

This leads into Wells' next distortion, about the genetic similarities between humans and apes:

"If you assume, as neo-Darwinism does, that we are products of our genes, then you're saying that the dramatic differences between us and chimpanzees are due to two percent of our genes... The problem is that the so-called body-building genes are in the ninety-eight percent. The two percent of genes that are different are really rather trivial genes that have little to do with anatomy. So the supposed similarity of human and chimpanzee DNA is a problem for neo-Darwinism right there." [p.54]

This passage implies that Wells rejects not only evolution, but genetics itself, which would put him well on the way to rejecting every discovery in biology in the last several hundred years. What explanation is he proposing for the differences between humans and chimps if he doesn't think it's due to genes? Do tiny angels with hammer and chisel reshape human embryos in the womb?

That aside, the evolutionary explanation neatly accounts for this supposed difficulty. Humans and chimps, after all, have the same body parts in the same basic arrangement. Our "body-building" genes don't need to be much different. What is different is the genetic master switches, the developmental program, which has been altered to emphasize certain features and reduce others. Indeed, it's widely understood that many of the differences between human and chimp stem from a developmental principle called neoteny: the retention of juvenile features into adulthood. To put it another way, humans look a lot like larger versions of baby chimps. This is most apparent if you look at our skulls:

Top row: A fetal, infant, and adult chimpanzee skull. Bottom row: Fetal and adult human skull. Note how the adult human strongly resembles the infant chimp.

The final card Wells has to play is the one that creationists always use to explain away homology, the "common design" argument.

"A designer might very well decide to use common building materials to create different organisms, just as builders use the same materials - steel girders, rivets, and so forth - to build different bridges that end up looking very dissimilar from one another." [p.55]

The flaw in this argument is that, although it can explain isolated similarities on an ad hoc basis, it cannot explain the overall pattern of similarities we see in living things. Designers, particularly omnipotent ones, are not constrained by past history in their work. They are not limited to variations or elaborations on designs they've already produced. They can borrow useful designs from anywhere and incorporate them into their plans.

But when we observe life on Earth, we don't see this kind of mix-and-match planning. We don't see dolphins with gills, bats with feathers, and so on. Instead, what we see are organisms whose adaptations apparently are constrained by past history. The mammal five-finger pattern is a clear example: it has no obvious explanation under common design (how would "common building materials" explain why a designer chose to repeat a pattern with no apparent purpose?). But it's just what we'd expect if mammals were all descended from a common ancestor with five fingers.

As the old saying goes, the more things change, the more they stay the same. That slogan excellently summarizes the principle of homology. Even though the bodies of living creatures have changed dramatically to adapt to different environments, they still retain the deep similarities that point to their common descent from ancient ancestors.

Other posts in this series:

• Rebutting The Case for a Creator