The Case for a Creator: Meet Your Ancestors

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.

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July 31, 2009, 6:55 am • Posted in: The ObservatoryPermalink164 comments

The Case for a Creator: Ancient Wings

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.

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July 17, 2009, 7:20 am • Posted in: The ObservatoryPermalink25 comments

The Case for a Creator: The More Things Change

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:

Below: Examples of homology in vertebrate limbs: Bats, moles, and dugongs all have five fingers. From Carl Zimmer, At the Water's Edge, p.58.

Vertebrate Homology

"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:

Neoteny in humans

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.

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July 10, 2009, 6:42 am • Posted in: The ObservatoryPermalink26 comments

The Case for a Creator: Beating a Dead Haeckel

The Case for a Creator, Chapter 3

Ernst Haeckel died a hundred and fifty almost a hundred years ago [fixed - thanks, Alex!], but the creationists won't let him rest in peace. In this section, Wells again exhumes these old bones and takes a few kicks at them, and imagines that by doing so he's brought the entire edifice of modern evolutionary biology crashing down.

If you're not familiar with Haeckel, here's a bit of background. Ernst Haeckel was a nineteenth-century biologist, one who lived at about the same time as Charles Darwin. He's best remembered for his dictum "ontogeny recapitulates phylogeny", meaning that a developing embryo retraces the evolutionary history of its ancestors - i.e., a human fetus first passes through a fish-like stage, then an amphibian-like stage, then a reptile-like stage, and so on. Haeckel is also infamous for defending this claim by using his own drawings of developing embryos, which turned out to be faked to exaggerate the stages he claimed were there.

What makes this more than a hundred-year-old cautionary tale is that creationists claim that Haeckel's drawings are still presented in textbooks as evidence for evolution. Here's how Wells puts it:

"They're still being used, even in upper-division textbooks on evolutionary biology. In fact, I analyzed and graded ten recent textbooks on how accurately they dealt with this topic. I had to give eight of them an F. Two others did only slightly better; I gave them a D." [p.48]

Strobel chimes in, declaring that he too remembers being taught about these drawings as evidence for evolution, and that "anger was brewing inside of me" [p.48] as he realized that he had been duped.

I'll give Strobel the benefit of the doubt and assume he's confabulating memories. Wells, however, I don't intend to treat so charitably: again, he is lying, making statements which he must know are false. P.Z. Myers quotes one of the books which Wells disparages by claiming that it is "resurrecting Haeckel", Campbell's Biology:

The theory of recapitulation is an overstatement. Although vertebrates share many features of embryonic development, it is not as though a mammal first goes through a 'fish stage', then an 'amphibian stage', and so on. Ontogeny can provide clues to phylogeny, but it is important to remember that all stages of development may become modified over the course of evolution.

Myers also cites a post listing a large number of other college textbooks that point out the problems with Haeckel's hypothesis. Out of 15 books reviewed, only one presents recapitulation uncritically - and that one is from 1937!

All of Wells' indignation is a smokescreen, intended to cover up an uncomfortable point: namely, vertebrate embryos do pass through a stage, called the phylotypic stage or the pharyngula, in which they all look very similar. Haeckel's biogenetic law was a hypothesis intended to explain that observation. By criticizing one particular faulty hypothesis, Wells hopes to cast doubt on the observation itself.

Wells repeatedly attacks textbooks for making claims such as "the early embryos of most vertebrates closely resemble one another" [p.50], implying that this is an endorsement of Haeckel. In fact, this is a completely true statement, referring to the phylotypic stage. These patterns of embryological development are real, and they do not disappear just because one particular explanation of their origin is falsified.

To take the measure of Wells' mendacity, realize that when he gives "grades" to textbooks, he lowers the grade if the book contains actual photos of embryos. He considers this a "misleading" tactic when it comes to making the case for evolution. Why, we wouldn't want to show people what embryos actually look like, do we? It might give them the wrong idea!

This fact explains Wells' great annoyance over the term "gill slits", a lay term for branchial arches, which are a structure common to embryos at the phylotypic stage. Wells insists, despite the name, that these are not gills [p.51]. This is true, but unfortunately for him, he then goes on to undermine his own argument:

"In humans, the ridges become one thing; in fish, they become gills." [p.51]

It's correct to say that human embryos do not have gills. (That would be Haeckel's biogenetic law.) But the more important point is one that Wells, unintentionally I'm sure, has illustrated: vertebrate embryos pass through a stage where they are very similar, and the same structures that exist in the embryonic forms of many species develop into completely different adaptations in the adult forms of those species. This is a phenomenon that evolution provides a good explanation for. How, or whether, ID can explain it is a question never raised in this book.

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June 27, 2009, 11:19 pm • Posted in: The ObservatoryPermalink13 comments

The Case for a Creator: Small Twigs

The Case for a Creator, Chapter 3

Jonathan Wells' second "icon" is Darwin's tree of life, which he says is a "dismal failure" [p.43] as an illustration of the fossil record.

With a lead-in like that, you'd expect a typical creationist jeremiad against transitional fossils. In fact, that's not what we get. The focus of Wells' complaint is about the Cambrian explosion, 550 million years ago. No transitional series more recent is treated here: not the origin of tetrapods, not the therapsids which illustrate the evolution of reptiles into mammals, not the beautiful and compelling whale transitional series, and certainly not the emergence of the human species. Wells never even mentions these compelling, and indisputably relevant, examples of evolutionary transition preserved in the fossil record. Instead, the source of his ire dates all the way back to the origins of modern phyla:

"Darwin knew the fossil record failed to support his tree. He acknowledged that major groups of animals - he calls them divisions, now they're called phyla - appear suddenly in the fossil record. That's not what his theory predicts." [p.43]

This is a lie. For the record, Darwin was well aware of the imperfection of the fossil record, and devoted an entire chapter of his book to explaining why we should not expect to see clear transitions preserved. If anything, he was too pessimistic, and our paleontological surveys have surpassed his expectations.

"Then at the beginning of the Cambrian - boom! - all of a sudden, we see representatives of the arthropods, modern representatives of which are insects, crabs, and the like; echinoderms, which include modern starfish and sea urchins; chordates, which include modern vertebrates; and so forth. Mammals came later, but the chordates - the major group to which they belong - were right there at the beginning of the Cambrian.
    This is absolutely contrary to Darwin's Tree of Life. These animals, which are so fundamentally different in their body plans, appear fully developed, all of a sudden..." [p.44]

Wells' argument is that the various phyla are so different in their body plans, they could not possibly have all diverged from a common ancestor in such a brief period of time. The best answer to this is a clever analogy originally proposed by Richard Dawkins to clear up just this sort of confusion:

Suppose you have a great oak tree with huge limbs at the base and smaller and smaller branches toward the outer layers where finally there are just lots and lots of little twigs. Obviously the little tiny twigs appeared most recently. The larger boughs appeared a long time ago and when they did appear, they were little twigs. What would you think if a gardener said, "Isn't it funny that no major boughs have appeared on this tree in recent years, only small twigs?"

Strobel and Wells would like their readers to believe that the various phyla were already radically different from each other at the time of the Cambrian explosion. This is not the case.

The phyla are like the twigs on Dawkins' tree. Originally, far back in the Cambrian, they were very similar to each other. But over great spans of geological time, they have diverged farther and farther, and what were originally slight differences became accentuated by evolution to fit the varying lifestyles to which they adapted. Today, the living representatives of these groups have major differences from each other, and looking all the way back, we can see how those differences developed from what were originally slight distinctions. In that sense, it's fair to say that the "fundamental body plans" first appeared in the Cambrian. But that's not the same thing as saying that the earliest members of these groups were radically different when they lived side by side.

When Wells speaks of "major groups", he subtly misleads the reader. Based on his examples, a lay reader might erroneously conclude that starfish, crabs, reptiles, insects, and the like all just suddenly appeared during the Cambrian. In fact, as already stated, most species of the Cambrian explosion were relatively similar, and none of them looked much at all like the modern groups that are thought to have descended from them. Here are several Cambrian animals that Wells claims represent "major groups" that are "fundamentally different in their body plans". Can you tell which one is the ancestor of what modern group?

(All images from the Smithsonian's Burgess Shale Fossil Specimens page.)

If you've given up, the first of these animals is called Aysheaia, and is thought to be an ancestor of the velvet worms (phylum Onychophora), segmented worm-like animals with rows of clawed feet. The second is Canadia, believed to be an ancestor of annelids (phylum Annelida), whose modern representatives include earthworms and leeches. And the last is Pikaia, believed, with some dissenters, to be an ancestor of the phylum Chordata - us. All modern animals with dorsal nerve cords - fish, amphibians, reptiles, birds, mammals - all of them were represented in the Cambrian by this tiny, one-inch-long free-swimming creature.

These supposedly vast phylum-level differences, in the beginning, were trifling things. It's only time and evolution that have turned these small twigs into great branches spreading far and wide.

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June 20, 2009, 10:38 pm • Posted in: The ObservatoryPermalink12 comments

Science Needs Good PR

My recent post on Project Steve brought several comments arguing that it's pointless to take a survey of scientists, like this one from Freidenker:

Frankly, I have no idea whatsoever how many scientists accept or reject evolution, and furthermore - it doesn't matter: even if all scientists all over the world rejected evolution, the evidence for evolution is still there. really survey the scientific community for evolution support is truly a stupid thing to do: popularity has no bearing on scientific validity.

Reasonable as this sounds, I believe it's misguided, and in this post I'll try to explain why.

If we were waging a debate in the peer-reviewed literature, trying to convince other scientists to accept evolution, then citing the evidence would be the thing to do. But this isn't a scientific debate; as we should all well know, creationists are not scientists, and have no interest in evidence. They're advancing a religious belief which they hold regardless of what the facts say. Moreover, their objective is not to freely convince scientists, but to bypass the process of peer review altogether, and to directly force their beliefs to be taught in schools by lobbying school boards and legislatures.

In short, creationism is not a scientific movement, but a public-relations movement. Their goal is not to change scientists' minds - for how could they possibly convince the experts? - but to influence the public's perception. And to be victorious, we have to fight them on the same ground.

If we try to make the case for evolution solely by citing the evidence, we're playing into the creationists' hands. They can easily respond by saying, "That's very interesting, but we have lots of evidence of our own. The [cell/bacterial flagella/bombardier beetle/blood clotting cascade/take your pick] is so complex it couldn't possibly have evolved on its own! There must have been a Designer. Teach the controversy!"

Against laypeople and the uninformed - and, unfortunately, school boards and legislatures include generous quantities of each - this is an effective line of attack. A person who lacks the expertise to evaluate the scientific evidence, and to see that the creationist case is hogwash, will come away with nothing but the impression that both sides have good evidence of their own, so why not be fair and teach them both? It's this superficial sense of fairness that the creationists count on.

To defeat this tactic, it's not enough to cite evidence that the creationists can counter with "evidence" of their own. What we need is to go further and show that there is no genuine controversy, that real, practicing scientists are all but unanimous in their support of evolution, and more, that creationists have avoided laying their case before the people best qualified to evaluate it.

That's why efforts like Project Steve, lighthearted as they are, make an important point. Ordinary people may not know much about the scientific method, but they respect the authority of scientists. Laypeople may be ill-prepared to decide the merits of dueling arguments, but when they see that all the scientists line up on one side, that is something they can understand. This is why creationists fight so hard to give the impression that plenty of real scientists support creationism - and we must not concede that point to them! It's vital to show that their list of "scientists who doubt Darwinism" is, in reality, just a minuscule and carefully cultivated minority of dissenters, one that's swamped by the overwhelming tide of working scientists who not only accept evolution but rely on it in their work every day.

Yes, we should present the evidence for evolution - strongly and comprehensively. We should always be ready to show the public the many wonderful transitional fossils we've found. We should always be ready with evidence of new mutations that increase genetic information, new and incipient species in the process of formation, and maps of gene trees that illustrate the nested hierarchy of descent. But to supplement all this evidence, we must also be prepared to prove that these arguments actually have convinced scientists, and that the creationists' arguments have not. Only this two-pronged strategy can effectively undermine the creationist case and win acceptance of evolution in the eyes of the public.

June 12, 2009, 6:49 am • Posted in: The ObservatoryPermalink20 comments

The Case for a Creator: Facts About VD

The Case for a Creator, Chapter 1

We pick up where we left off, with self-proclaimed former skeptic Lee Strobel interviewing a rural Appalachian community whose inhabitants were violently resisting the teaching of evolution. As we'll see, Strobel believes a person can be fully justified in advocating creationism. Yet it seems improbable that these isolated, deeply religious communities were thoroughly acquainted with the complicated philosophical and scientific arguments he deploys later in the book. Their staunch rejection of science was not based on any detailed knowledge of the subject matter. Rather, the real reason for their anger was laid out, albeit unintentionally, in several different interviews:

"The books bought for our school children would teach them to lose their love of God, to honor draft dodgers and revolutionaries, and to lose their respect for their parents," insisted the intense, dark-haired wife of a Baptist minister... [p.9]

The preacher... turned to the crowd and held aloft a book titled Facts about VD. "This is gonna turn your stomachs, but this is the kind of book your children are reading!" [p.15]

And a local businessman:

"Let me put it this way," he said. "If Darwin's right, we're just sophisticated monkeys. The Bible is wrong. There is no God. And without God, there's no right or wrong. We can just make up our morals as we go. The basis for all we believe is destroyed. And that's why this country is headed to hell in a handbasket. Is Darwin responsible? I'll say this: people have to choose between science and faith, between evolution and the Bible, between the Ten Commandments and make-'em-up-as-you-go ethics. We've made our choice - and we're not budging." [p.11]

As you can clearly see from these quotes, the primary reason these West Virginians were so upset about evolution is not because they believed it was incorrect - though they certainly believed that - but because they disliked what they saw as the consequences of teaching it. They preferred to choose their belief, and their children's beliefs, based not on what is true but on what they wanted to be true.

The residents were also enraged that anyone might want to study Christianity any way other than devotionally, as that businessman goes on to say:

"Listen to what Dynamics of Language tells our kids," he said as he quoted an excerpt from the textbook: "Read the theory of divine origin and the story of the Tower of Babel as told in Genesis. Be prepared to explain one or more ways these stories could be interpreted." He tossed the well-worn clipping on the table in disgust. [p.11]

Horrors! Children might learn in school about alternative interpretations of religion? Why, those wicked school administrators even wanted to teach them facts about STDs! What's next - teaching them to question and think critically? How could any self-respecting Christian community permit that?

One would think that, at this point, a rational, hard-nosed journalist would point out that the possible social consequences of a scientific theory have no bearing on whether that theory is true. Strobel does not do this. Instead, he seemingly underlines and excuses his interviewees' fears with the following incredible assertion:

Darwin's theory of evolution... meant that there is no universal morality decreed by a deity, only culturally conditioned values that vary from place to place and situation to situation. [p.16]

Leave aside the evolutionary biologists who are Christian. (We'll get to them later.) Strobel's astonishing claim is that evolution being true would rule out not just Christianity, but all possible beliefs about God. As an atheist, I have to admit I'd be greatly pleased if that were true, but it just doesn't follow by any conceivable chain of logic. Why would evolution rule out a deity who creates through evolution and who also decrees a universal morality for humans? Strobel doesn't say.

But the lunacy about evolution and morality isn't over yet. In the next installment, it will become more ridiculous still.

Other posts in this series:

April 10, 2009, 6:47 am • Posted in: The ObservatoryPermalink48 comments

Evolutionary Algorithms

One of the bedrock claims of creationism is that mutation can never create new information, that random changes can only make complex systems worse and never improve them. Although there are many examples of information-increasing mutations in the natural world that prove this claim false, there's an even more potent and understandable counterexample, one that I think defenders of evolution too often overlook. That counterexample comes in the form of evolutionary algorithms.

Altshuler and Linden used EAs to design this crooked-wire antenna. Despite its strange, asymmetric shape, it has a nearly perfect hemispherical radiation pattern. (source)

Evolutionary algorithms are a type of computer simulation that uses evolution as a design tool. In an EA, the problem to be solved is represented as a fitness function, a quantitative metric that measures how well a proposed solution meets the parameters of the problem. An EA begins with a population of candidate solutions, usually generated at random, and uses the fitness function to evaluate each of them. The best candidates are copied with random mutations, creating "offspring" that go on to the next generation, and the process repeats. Some EAs even simulate sex by allowing candidate solutions to swap parts of their code.

As simple as this sounds, evolutionary algorithms have proven their worth as a problem-solving strategy of dramatic creativity and power, often producing solutions that surpass the best efforts of human engineers. EAs are widely used in academia and industry to get a handle on problems that seem intractable by any other method.

EAs have two major advantages over human design techniques. One is their open-mindedness. Because EAs operate through randomness, mutating their candidate solutions without trying to predict in advance whether the changes will be beneficial, they are not limited by human preconceptions about how a problem should be approached. The only thing that "matters" to an EA is results, and as a consequence, they often come up with solutions that a human designer would never have thought of.

Computer simulations suggest this EA-designed expandable truss for an aircraft or satellite would damp out damaging vibrations much better than an ordinary design. (source)

The other advantage, more subtle, is called the Schema Theorem. Many important problems in industry and science exhibit combinatorial explosion - that is, they have so many different possible solutions that it would be impossible to individually test each one, even on a computer. This vast number of candidates can be grouped into what are called search spaces, collections of individuals that are similar in important ways. The idea behind an evolutionary algorithm is that, by evaluating an individual from a given search space, it's learning something about all the individuals in that search space. As it repeats this process, it will gradually build up more and more accurate information about the average fitness values of these spaces, until it can home in on the one that's most likely to contain the answer being sought. This sounds complicated, but fundamentally it's the same thing that a scientific poll does. Pollsters ask questions of a certain member of an ethnic, religious or social group because they expect to learn something about the opinions of all members of that group, and therefore gain the ability to predict national opinion after sampling only a small fraction of the population.

But far more important than these theoretical concerns is the empirical evidence demonstrating the power of evolutionary algorithms, and the facts do not disappoint. EAs have been used throughout academia, industry and government to solve problems that seemed insoluble or to come up with answers that outclass their best human-designed competitors. They have been taught to play expert checkers, to design wings for supersonic aircraft, to predict stock market swings and currency exchange rate fluctuations, to schedule assembly lines and air traffic, to control automobile anti-lock braking systems, to optimize engines and turbines, and many more. Here are some other examples of evolutionary algorithms in the news over the past few months:

The next time an ignorant creationist insists that evolution can never produce anything complex, functional and useful, point him to the evidence of evolutionary algorithms. These algorithms permit us to view evolution at work in real time, and in human technology, as in organic life, it proves to be a problem-solving strategy of surpassing flexibility and power.

March 18, 2009, 6:31 am • Posted in: The ObservatoryPermalink25 comments

Noble Africa

To those who are following the continuing genocide in Darfur, every day brings grim headlines:

Fighting has prompted thousands of people in the southern part of Sudan's Darfur region to seek security and shelter at a refugee camp in the northern part of the war-torn area, according to the United Nations.

...An estimated 300,000 people in the western Sudanese region have been killed through combat, disease or malnutrition, according to the United Nations. An additional 2.7 million people have been forced to flee their homes because of fighting among rebels, government forces and the violent Janjaweed militias.

Though its plight has attracted the most attention, Darfur is far from the only troubled region of Africa. There's the failed state of Somalia, now a haven for terrorism and piracy, and the outbreaks of famine and cholera brought on by the near-total collapse of Zimbabwe in the face of dictator Robert Mugabe's refusal to surrender power, to name just the two most prominent examples from recent headlines. How did we let this happen?

Africa was the human race's first home. It is our birthplace, our cradle. The continent should be a sacred place to all of us, a living temple of memory reminding us of our origins. Instead, it's poverty-stricken, politically fractured, still laboring under corrupt autocracies and mired in backwardness and superstition. The picture is not all bleak - there are success stories, and notable bright spots - but even so, Africa as a whole lags behind the rest of the world, and still struggles with the legacy of imperialism and the unbridged chasms of its own political divides.

And yet, there was a time when all humans were Africans. Though we've spread all over the world in successive waves of migration, our genes have not forgotten the past. Whether you're European or Asian, from the Arctic or from Polynesia, your heritage can be traced back to families that lived in Africa millions of years ago. If you care to categorize on the basis of something as superficial as skin color, then you can know to a certainty that the blood of black men and women flows in your veins.

It was Charles Darwin who ventured the bold guess that the human race evolved in Africa, and the evidence has vindicated him. It's in Africa that we find the bones of our earliest known ancestors and our close cousins in the human family tree: species like Lucy's, Australopithecus afarensis, small hominids who had the heavy brows and brain size of chimpanzees but stood and walked upright like us. It's in Africa, in Laetoli, that we find the oldest trace evidence of human bipedalism: two trails of footprints frozen in stone, four million years old, where three people - perhaps a family of man, woman and child - walked together across a field of new-fallen volcanic ash. It's in Africa, in Tanzania's Olduvai Gorge, that we find the earliest stone tools. And more controversially, it's in Africa, at sites like Kenya's Koobi Fora, that we find possibly the earliest evidence for the domestication of fire.

In short, it's in Africa that we learned to be human. It was under the shade of Africa's trees that we first descended to the ground, and on African savannas that we stood upright and walked for the first time. The songs of our childhood were first sung beneath an African dawn; the stories that echo in your bones were first told around African campfires.

Of course, we did not stay in our birthplace forever. As the population grew and wanderlust took the human spirit, we flowed out in successive waves of settlement and conquest. We spread north into the fertile crescent of the Middle East, where we first domesticated animals and plants and built the world's oldest cities, and into Ice Age Europe, where we eradicated our brothers - the stocky, heavy-browed Neanderthals, who had lived and thrived in the frozen landscape for tens of thousands of years until we arrived. We walked across the Bering Strait into the Americas and fanned out across the Pacific by raft and canoe. We spread over the face of the earth, building mighty civilizations and forging empires in battle and conquest. And, in due time, the conquerors returned - to their own birthplace, had they but known it - and put it under their heel as well.

It took centuries for Africa to throw off that yoke, and the injuries that it suffered still are not fully healed. Its people still grapple with endemic disease, with political corruption and with their own tribalisms, all of which are exacerbated by poverty and international neglect. But still and all, Africa is a noble continent, not in the condescending caricature of the "noble savage", but nobility in the true sense of the word: those whose blood is purest, whose lineage traces back longest. It is still the home of the most deeply rooted branches of the human family tree: as Richard Dawkins writes in The Ancestor's Tale, the disappearance of everyone outside Africa would decrease human genetic diversity only slightly, while the disappearance of everyone in that continent would mean the loss of most of our species' gene pool. Compared to Africa, all the rest of humanity is a prodigal son, descended from a relatively small number of restless wanderers who left a great and ancient family to seek their fortunes in the world.

In the slow ascent of human progress, we have many milestones left to reach. There are ancient trouble spots throughout the world, and we can count ourselves more advanced as we overcome each of them. But the turmoil of Africa is our species' greatest shame. I can imagine an Earth where Africa takes its rightful place among the pantheon of peoples; an Africa where the archaeological sites of humanity's origin are sites of pilgrimage, sacred places preserved for all to see and walk in the footsteps of our ancestors. I can imagine an Africa that's peaceful and prosperous, where gleaming cities exist alongside the simple beauty and grandeur of the savannahs and rainforests that were our childhood home. We may, perhaps, have no right to call ourselves truly advanced until that world is a reality.

March 6, 2009, 7:55 am • Posted in: The ObservatoryPermalink23 comments

Answering Lee Strobel's Questions for Atheists

Friendly Atheist has posted the third part of a dialogue with Christian apologist Lee Strobel. In it, Strobel poses questions that he thinks would be the most effective at planting seeds of faith in an atheist's mind. In this post, I'll answer those questions. I've written on some of these issues at greater length in the past, and I'll also provide links to those essays where appropriate.

Historian Gary Habermas: "Utilizing each of the historical facts conceded by virtually all contemporary scholars, please produce a comprehensive natural explanation of Jesus' resurrection that makes better sense than the event itself."

These historical facts are: (1) Jesus was killed by crucifixion; (2) Jesus' disciples believed that he rose and appeared to them; (3) The conversion of the church persecutor Saul, who became the Apostle Paul; (4) the conversion of the skeptic James, Jesus' half-brother; (5) The empty tomb of Jesus. These "minimal facts" are strongly evidenced and are regarded as historical by the vast majority of scholars, including skeptics, who have written about the resurrection in French, German, and English since 1975. While the fifth fact doesn't have quite the same virtual universal consensus, it nevertheless is conceded by 75 percent of the scholars and is well supported by the historical data if assessed without preconceptions.

Ebon Musings: Choking on the Camel

Even if we grant that dubious 75% figure, what Habermas fails to acknowledge is that most of the scholars who study the historicity of Jesus are Christians, and are unlikely to produce conclusions that deviate from orthodoxy, even if - as in this case - those conclusions are supported by no evidence outside the biblical record itself. Habermas' alleged "historical facts" are just the tenets of Christian belief presented in a facade of neutrality.

As such, I don't intend to begin by making the concessions he would prefer. I maintain that of his five facts, (1) is recorded primarily in the Bible, and only secondarily, and spottily, in some documents written decades later. (2) is mostly correct, so long as we remove the question-begging assumption that the first Christians were disciples personally chosen by Jesus. (3) and (4) derive from no evidence I know of outside the Book of Acts, which was written for apologetic purposes and which Habermas has naively accepted as historical truth (see below). (5), again, is just a derivation from the creeds of Christian orthodoxy, not from any historical documents which suggest that first-century non-Christians acknowledged this.

For a comprehensive natural explanation, I propose this alternative: The first Christians believed that Jesus was a savior deity, similar to those of other mystery religions of the time, whose sacrificial death and resurrection was a sacred mystery that took place in a higher, heavenly plane and was revealed to believers through visions and revelations. Allegorical documents like the Gospels set the activities of this mythological figure in recent history for teaching purposes. Over time, through war and disruption, the original purpose of these writings was forgotten. This explanation neatly accounts for most of the available facts, including the vague and fragmentary references to Jesus in early historical documents that gradually become more concrete, the lack of reference in the epistles to a human life and career of Jesus, and the first Christians' apparent lack of interest in sacred relics or holy places of their religion.

Philosopher Paul Copan: "Given the commonly recognized and scientifically supported belief that the universe (all matter, energy, space, time) began to exist a finite time ago and that the universe is remarkably finely tuned for life, does this not (strongly) suggest that the universe is ontologically haunted and that this fact should require further exploration, given the metaphysically staggering implications?

Ebon Musings: Unmoved Mover: The Fine-Tuning Argument

I take strong exception to the claim that the universe is "remarkably finely tuned for life". On the contrary, simple observation suggests that the universe is not well suited to life such as ours. When we consider the entire volume of the cosmos, we see that 99.999999... percent is cold, hard vacuum with a temperature of 3K. Within the galaxies, most of the interstellar medium is flooded with radiation. Most of the planets we've discovered are either freezing cold or boiling hot, unsuitable for life. In fact, in all the vastness of the cosmos, we only know one place where life can thrive - our own world - and even there, it's restricted to a relatively narrow range of habitable zones and climates. A universe "finely tuned" for life should produce it abundantly; but in fact, life is confined to a single, infinitesimally small and fragile corner. This strongly suggests that life, far from being the intended purpose of the universe, was an unintended side product arising from a confluence of rare and unlikely circumstances.

And, second, granted that the major objection to belief in God is the problem of evil, does the concept of evil itself not suggest a standard of goodness or a design plan from which things deviate, so that if things ought to be a certain way (rather than just happening to be the way they are in nature), don't such 'injustices' or 'evils' seem to suggest a moral/design plan independent of nature?

Absolutely not! The injustices and evils that we perceive are not intrinsic properties of the universe, but qualities of human perception. We evaluate natural phenomena based on whether they have a harmful or beneficial effect for us. Often those effects are harmful, but this doesn't imply that the universe has deviated from an original plan of goodness - that belief is a product of Christian presuppositions - only that natural phenomena occur randomly and don't take human needs into account. In reality, the randomness and amorality of nature is a much stronger argument for atheism than it is for theism.

Talk show host Frank Pastore: "Please explain how something can come from nothing, how life can come from non-life, how mind can come from brain, and how our moral senses developed from an amoral source."

Ebon Musings: Pay No Attention to the Deity Behind the Curtain

Pastore is asking for a full account of the current state of several entire scientific disciplines - cosmology, abiogenesis, and the evolution of the conscious mind. This is more than I'll attempt to explain or even summarize in this space, but I do have one shorter observation. If Pastore's question is meant to raise doubts in atheists, it can only be an example of the "God of the Gaps": the belief that anything not currently known must be miraculous.

The fallacy is a glaringly obvious one. Throughout human history, countless natural phenomena that were not understood were attributed to divine action: mental illness, contagious disease, the seasons, weather, fertility, life and death, and many more. Without exception, these supernatural explanations have receded and been replaced by natural ones as our knowledge grows. Pastore is just applying this tactic to the issues where we don't yet know the full answers, trusting that this time the gaps will remain impenetrable, and expecting that supernatural answers should be accepted despite their repeated past failures. But if we go by track record, we should all admit that the more likely answer is that these phenomena will turn out to be natural ones as well.

Historian Mike Licona: "Irrespective of one's worldview, many experience periods of doubt. Do you ever doubt your atheism and, if so, what is it about theism or Christianity that is most troubling to your atheism?"

Yes, I do occasionally experience doubt, as I've written about before. That's a necessary consequence of having an open mind. But what I generally find gives me the most uncertainty is unfamiliarity. I'm not the kind of person who can dismiss a claim out of hand without looking into it, and claims I've never heard before usually give me a moment's pause for that reason. But so far they've all failed to pan out, and the more I learn about most religious and supernatural claims, the less plausible they seem.

Author Greg Koukl: "Why is something here rather than nothing here? Clearly, the physical universe is not eternal (Second Law of Thermodynamics, Big Bang cosmology). Either everything came from something outside the material universe, or everything came from nothing (Law of Excluded Middle). Which of those two is the most reasonable alternative? As an atheist, you seem to have opted for the latter. Why?"

Ebon Musings: Unmoved Mover: The Cosmological Argument

Atheists are not committed to believing that "everything came from nothing". Koukl's alleged dichotomy overlooks a third alternative: that we simply do not know the ultimate origins of the universe at present, and that we can accept this as our answer for the time being until more evidence is discovered. As with Pastore's question, Koukl assumes that a supernatural explanation, even one with no evidence in its favor, "wins" by default if a natural explanation is not currently known - this despite the well-established pattern of natural explanations replacing supernatural ones over time.

I didn't email Alvin Plantinga, considered by many to be among the greatest philosophers of modern times. But based on his assertion that naturalism is self-defeating, we could formulate this question (thanks to William Lane Craig for some of the concise wording): If our cognitive faculties were selected for survival, not for truth, then how can we have any confidence, for example, that our beliefs about the reality of physical objects are true or that naturalism itself is true? (By contrast, theism says God has designed our cognitive faculties in such a way that, when functioning properly in an appropriate environment, they deliver true beliefs about the world.)

Daylight Atheism: Are Evolved Minds Reliable Truth-Finders?

The fallacy of this argument is its assumption that "survival" and "truth" are two different objectives, such that they could be selected for independently of each other. But it should be obvious that, all else being equal, greater accuracy in perceiving the world will always be a survival advantage. Granted, evolution can and does take shortcuts, producing well-known psychological fallacies like the urge to anthropomorphize natural phenomena, and many people have been misled in this way. But even here we are not helpless. By using cognitive prostheses like science, we can compensate for our mental shortcomings and learn to view the world still more accurately.

By contrast, a theist who believes that God has designed our cognitive faculties to be accurate is faced with the embarrassment of explaining why there are so many conflicting and incompatible religions. How is this so, if we are designed to perceive the world accurately? Why is there so much confusion, ignorance and error among humans when it comes to determining what the true faith is?

For me, when viewing all Strobel's questions, what stands out about them is their ordinariness. I concur with Greta Christina that these arguments, far from being anything new or unusual, are no different - and no more difficult to defeat - than those of the run-of-the-mill amateur apologists that most atheists encounter on a routine basis. That's not surprising, of course, since most of those people take their cues from the leading apologists.

But for the same reason, it's meaningful because this should give us confidence - confidence that we truly can stand up to the superstars of modern apologetics and answer the best that they have to offer. It's not even difficult. Any reasonably well-versed atheist should be able to shoot down these arguments without a problem. If this is truly the best they have to offer, then we can be all but certain that the evidentiary base of Christianity does not have anywhere near the depth or breadth that would justify an atheist's conversion.

February 2, 2009, 7:56 am • Posted in: The LibraryPermalink65 comments

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