Archive for the ‘history of science’ category

The failure of Intelligent Design

February 18, 2011

“Were there no example in the world of contrivance except that of the eye, it would be alone sufficient to support the conclusion which we draw from it, as to the necessity of an intelligent Creator.  It could never be gotten rid of; because it could not be accounted for by any other, supposition, which did not contradict all the principles we possess of knowledge.[i]

–William Paley, Natural Theology, 1857

“To suppose that the eye, with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest possible degree.  Yet reason tells me, that if numerous gradations from a perfect and complex eye to one very imperfect and simple…can be shown to exist…then the difficulty of believing that a perfect and complex eye could be formed by natural selection, though insuperable by our imagination, can hardly be considered real.[ii]

– Charles Darwin, On the Origin of Species, 1859

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

–Michael Behe, 1996.

Charles Darwin refuted the teleological argument from design in 1859.  Apparently Behe didn’t get the memo.  Through his theory of evolution by means of Natural Selection, Darwin accomplished what earlier evolutionists could not.  Unlike previous theorists such as Lamarck and Erasmus Darwin, Darwin (and Alfred Russel Wallace working with him) provided a working mechanism for evolution. In short, Darwin’s theory of Natural Selection replaced Paley’s divine watchmaker with a blind watchmaker; the selective force of nature.  Following the strengthening of Darwinian theory by intellectuals on both sides of the Atlantic Ocean, especially after the development of the Modern Synthesis in evolutionary biology, evolutionary theory effectively replaced “Design” as a creative force.

Natural Selection, therefore, is able to explain organs and features of organisms formerly relegated to creation by an “intelligent Designer”, or a “divine watchmaker” of sorts.  Regardless of whether it is Paley’s eye or Behe’s bacterial flagellum, evolutionary theory effectively explains the development of these organs and features.  Therefore, the “Watchmaker hypothesis,” in both its historical and modern forms, does not present an effective challenge to the efficacy of evolutionary theory.  Thus, the argument from “Design”, or “irreducible complexity”, is not an adequate tool with which to challenge evolutionary theory.  Both fail to undermine the strength of evolutionary theory on closer inspection.  Although one might ask “what good is 2/10ths of an eye?”, any working “eye” is better than no eye at all.  Even if we are referring to just a few light-sensitive cells that are useful for an organism to detect light or predators, these cells will provide a definite survival advantage compared to organisms that lack these cells. In time, variation and selection can and do build more complex organs through differential survival rates.  In the case of “irreducibly complex” organs, the key flaw in Behe’s argument is the fact that he fails to account for the fact that so-called “irreducibly complex” organs can and do have other uses if a component or group of components are removed from them.  Natural selection works by jury-rigging and adaptation of available features, not by the design of new ones.  Therefore, the “watchmaker hypothesis” fails on all counts.

Another key aspect of modern arguments from design is the “fine-tuning” argument for the existence of the universe. This argument, stated simply, alleges that since the universe appears to be “finely tuned” for the existence of life as we know it (i.e. cosmological constants are exactly what they need to be for life to exist as we know it), that the universe therefore must be designed.  While this argument seems cogent at first glance, it is, in fact, fatally flawed.   In fact, the apparent “fine tuning” of the universe is exactly what one would expect if life evolved.  Natural selection produces organisms that are well-fit to their environment.  If life did, in fact, evolve, it did so in this universe, on this planet, governed by the constraints placed upon it by the existing cosmological constants.  You do not build a vehicle that sinks quickly but has really good wheels if you are only going to be using it in an ocean.  Rather, you construct a vehicle that is well-adapted for oceanic travel.  Natural selection works the same way.  It is governed by physics and chemistry as well as biology and ecology.  Natural selection, in short, is as much a slave to cosmological constraints as organisms are to their dietary requirements.  Thus, the cosmological argument is as much a failure as the “watchmaker hypothesis”.

Another key argument advanced by Intelligent Design proponents can be described in the following manner. The proteins/molecules/cells, etc. that make up life are extremely complex.  It is extremely improbable that they developed through solely naturalistic means. Therefore, these features must be designed.  However, this approach is philosophically and scientifically flawed.  Scientists have done a decent job exploring the origin of life. Even though scientists have not definitively explained the origin of life, they have developed some tantalizing glimpses at possible explanations for this event. This topic is relatively complex, and a bit intensive for a short post, so if you’re interested I’ll refer you to the work of Robert Hazen as a first guide to this topic. See, for example, his book “Genesis“. I will focus on the philosophical flaw with this argument in this post.

The philosophical argument inherent to this portion of the Intelligent Design argument can be re-phrased in the following manner.  A million (pick your favorite large number here, and replace “A million” with it if you’d like) lottery tickets are sold for a lottery. One ticket must win.  Each ticket represents a possible combination of proteins (the building blocks of DNA).  The “winning ticket” is the actual combination generated by nature.  According to the Intelligent Design approach, since a million tickets (possible protein sequences/amino acids) exist, the chances of drawing the winning ticket are extremely low, and therefore no ticket will win.  However, we know this to be false; one ticket ultimately DOES win.  Therefore, as improbable as the development of DNA sequences was, by nature, it was at least possible.  And, in fact, there are possible ways to increase the probability of the development of complex protein sequences (Hazen discusses the possibility of proteins growing within the microstructures of carbonate rocks, a hypothesis which explains the extremely high proportion of “left-handed” amino acids). Therefore, the Intelligent Design perspective once again proves flawed.

Before closing this essay, I will mention a few other key claims/approaches fronted by Intelligent Design proponents. The first is Dembski’s Explanatory Filter, which fails miserably as a tool to supposedly discern design in nature (see critique here). The second is the claim that natural selection cannot “increase information” in a genome.  Here’s a rebuttal for that claim as well.  Finally, perhaps the most ridiculous claim advanced by Intelligent Design advocates such as Stephen Meyer is the claim that the “Cambrian Explosion” somehow undermines evolution.  This is the old “there are GAPS!!!  Gaps in the fossil record!” argument trotted back out to play. Even a cursory glance at modern paleontology proves such a claim irreparably flawed.  A good explanation of why such an argument is flawed can be found in one of my all time favorite books on transitional forms, Donald Prothero’s “Evolution: What the fossils say and why it matters“.  For a good online critique of the “Cambrian Explosion” argument advanced by Design advocates, see Keith Miller’s article (part one here and part two).

Therefore, as demonstrated, upon closer inspection, the arguments against evolution advanced by Intelligent Design proponents consistently fail to withstand scrutiny.  I consciously avoided arguments from social ills in this post (“well evolution influenced Hitler, or communism, or what have you”) due to the extremely flawed nature of this type of argument.  What is more important is attacking so-called “science” of Intelligent Design.  As I’ve shown here, even a cursory critical glance at the pseudoscientific structure of Intelligent Design reveals massive and irreparable flaws. Therefore, Intelligent Design fails as a science.

Works Cited:
Behe, M.  Darwin’s Black Box: The Biochemical Challenge to evolution. Free Press, New York. 1996.

Darwin, CR. The Origin of Species.  Harvard University Press, Cambridge.  First Ed. facsimile, 2002 (1859)

Paley, W. Natural Theology: or, Evidences of the Existence and Attributes of the Deity, Collected From the Appearances of Nature. Gould and Lincoln, Boston, 1857

Happy Darwin Day 2011!

February 12, 2011

February 12th, 1809.

Two individuals are born an ocean apart, in vastly different economic settings.  One, an American, is born in a one-room cabin in Kentucky (just west of the old Colonial realm).  The other, a Englishman, is born in Shropshire, England, to a prominent doctor, himself the son of a major 19th Century intellectual, and the daughter of a prominent British pottery maker.  These individuals, of course, are Abraham Lincoln and Charles Darwin.

Although Darwin and Lincoln never directly corresponded, the two share more than a common birth-date.  Both were considered to be lazy during their formative years. More importantly, both were ardent abolitionists.  Lincoln grew into abolitionism from a more neutral position, ultimately issuing the Emancipation Proclamation on January 1st, 1863.  Lincoln, is remembered as much for the American Civil War as he is for ending slavery in America.  Charles Darwin became an abolitionist as a result of both first-hand experience and, possibly, family upbringing (the Wedgewoods were well-known British abolitionists).

Darwin and Lincoln, then, share a common historical legacy.  Both rejected slavery, Darwin for moral reasons, Lincoln perhaps for both moral and pragmatic reasons.  However, the two individuals are remembered differently by the general public.  Lincoln is often praised (at least in Northern America) for his decisive moves to both preserve the American nation through the Civil War and for ending American slavery.  Darwin, however, is condemned in many circles for his role in decentralizing the biological status of the human species through his theory of Descent with Modification by means of Natural Selection.

Does Darwin deserve to be condemned?  By publishing his theory, Darwin was not attempting to unilaterally destroy theism.  The Origin was published in a wider intellectual and historical context that already included multiple texts advocating “evolutionary” thought. Some famous predecessors to the Origin include Robert Chambers’ Vestiges of the Natural History of Creation (1844) and Lamarck’s evolutionary model (first documented in 1800).  Darwin’s grandfather, Erasmus Darwin, also published an evolutionary account of life in a book titled Zoonomia during the 1790s.  Natural Selection, then, was born into an intellectual scene which was already used to theories of evolution.  However, Darwin and Wallace’s Natural Selection had one feature that Lamarck, Chambers, and Erasmus Darwin’s work lacked: a working mechanism.  Therefore, Darwin (and to a lesser extent in the public realm Wallace) are remembered (wrongly) by many as the first evolutionists.  As a result, they are most often condemned for the idea of evolution.

Although evolutionary theory DOES have major implications for theology, evolutionary theory does not, in fact, disprove religion.  If one takes an extreme reductionist approach to theology and philosophy, evolutionary theory can be used in an attempt to reduce philosophy and theology to a mere consequence of physical and chemical forces.  However, as religious belief is a non-disprovable hypothesis (God could be out there, regardless of whether evidence exists for or against God’s existence), it is impossible to disprove God through mere science.  In fact, some theological positions incorporate both a relatively traditional conception of God and evolutionary theory.  For example, the Roman Catholic Church does not have an issue with evolution; they accept evolution as valid science, yet they also retain a role for creative acts by God.  Kenneth Miller’s Finding Darwin’s God provides a good example of one Roman Catholic biologist attempting to achieve a harmonious relationship between God and evolution, and is a worthwhile read.

Another key criticism of Darwin and evolution is that it creates social ills.  Evolutionary theory has been blamed for racism, the Holocaust, abortion, crossdressing, and numerous other things by its opponents.  However, such an approach is philosophically and scientifically unsophisticated.   Nuclear weaponry utilizes physics, so does that mean that Newton, one of the fathers of modern physics, is responsible for nuclear proliferation? Of course not! If I tried to make that statement, any sane person would (rightly) declare me to be a fool.  Scientific theories are not moral or immoral.  By nature, they do not have a moral stance (they are amoral).  They can be used for moral or immoral means, but a scientific theory, on its own, does not have a moral position.  Therefore, to blame evolution for society’s ills is at best an attempt to put a bandage on an underlying cause.  Darwinian theory is not, in itself, responsible for its application within society (for good causes or bad).  Yes, evolutionary theory was developed by human agents operating in specific places and times.  Therefore, there is an inherent human aspect to evolutionary theory. However, this human aspect is present in ALL scientific theories.  It is not the scientific theory that is the issue. It is how people choose to use it for extrascientific purposes.

Therefore, its time for society to stop condemning Darwin.  If you’ve got a problem with something in society, stop trying to blame people who are at best indirectly related to the root of the problem and actually attempt to fix the issue.  Let’s remember Darwin for what he actually DID contribute to society, rather than condemn him for the problems his theory allegedly caused.  The Darwinian Revolution is one of the key scientific revolutions in modern times.  And it is arguably the final step in the Newtonian Revolution.  First, Newton demonstrated that the universe operates according to fixed laws.  Then the heliocentrists come along and demonstrate that the Earth is not at the center of the universe.  Finally, Darwin comes along and places humanity right where it belongs, squarely within nature, as a part of nature rather than separate from it.  Although some might consider this step to be both theologically and scientifically radical, it is, to me, as elegant  to think of humanity as being intricately intertwined and tied to the rest of life on Earth as it is to think 0f humanity as somehow “above” and “separate from” nature.

The latter approach is flawed at its best, and dangerous at its worst. To forget that we are inherently and directly tied to the rest of the biosphere is to forget that our actions as a species have a direct, and often extreme, impact on that biosphere.  We are extremely capable of signing our own death warrants through our collective actions, and to accept that we are tied to the rest of the biosphere is to claim responsibility for our actions as well as for the wellbeing of life on Earth.  We are capable of destruction, yes, but we are also capable of preserving the small pockets of non-human life on this planet that we have not altered or destroyed.  This is one of the key lessons of the Darwinian Revolution, namely that the fate of the biosphere is inherently and directly responsible for our own fate as a species.

Darwinism, frankly, is not the root of all evil.  So let’s get over it, and fix the real problems facing this planet.  For me at least, crossdressing and atheism pale in comparison to starvation, homelessness, climate change, and the destruction of the biosphere.  First we need to fix the big problems facing humanity, and then we can argue about semantics.    Happy Darwin Day 2011, and don’t forget to remember Lincoln for a moment as well!

Megaloceros and orthogenesis

September 24, 2010

Megaloceros on display at AMNH

Megaloceros, commonly (and wrongly) known as the “Irish Elk” offers a good example of an organism utilized as proof of orthogenesis during the latter half of the 19th century and the early 20th century.  During this period, paleontologists utilized the term “orthogenesis” to explain trends in the fossil record.  Under the model of orthogenesis, once a species begins to develop, it continues to develop along that line and exhibits an inability to stop this process of development.  In the case of Megaloceros, the argument was structured such that through the process of orthogenesis, Megaloceros’ antlers grew to extreme sizes.  Ultimately, this unchecked antler growth caused the extinction of Megaloceros.  This example offers a good model to demonstrate why orthogenesis does not work.  A trait isn’t going to survive if it causes a problem for the survival of the organism in question.  Ultimately, even if selective pressures do support the development of larger antlers in Megaloceros, the antlers won’t get large enough to cause extinction.  If an individual Megaloceros has antlers so large that they end up getting caught in trees (part of the orthogenesis argument), then it’s not going to have much success with reproduction. Sure, a few individuals with extremely large antlers might get to reproduce, but as a rule, most of these will, in fact, be weaned from the gene pool.  This is why orthogenesis does not work.

If you’re interested in this topic, check out Stephen Jay Gould’s article “The misnamed, mistreated, and misunderstood Irish Elk.” The article is available in his 1977 book Ever Since Darwin.

Ontogeny trumps Phylogeny

September 24, 2010

A recent paper published by Museum of the Rockies paleontologists John Scannella and Jack Horner, “synonymy through phylogeny, illustrates that Torosaurus, a genus originally described by OC Marsh, is in fact an adult form of Triceratops.  For a basic article on the topic, click here.  The citation information for the original Scannella and Horner article is as follows, and is available here if you have access to the Journal of Vertebrate Paleontology:

Scannella, J., & Horner, J. (2010). Torosaurus Marsh, 1891, is Triceratops Marsh, 1889 (Ceratopsidae: Chasmosaurinae): synonymy through ontogeny, Journal of Vertebrate Paleontology, 30 (4), 1157-1168.

Publications such as this one highlight the difficulty with which paleontologists define species.  It’s generally impossible to go back and look at skin (with a few key exceptions, such as the hadrosaur “mummy” at the AMNH), behavior, or other non-skeletal traits.  Thus, paleontologists are stuck trying to define species and genera from bones  alone, more often than not.  However, this article highlights the self-correcting nature of science.  While any historian of science can highlight numerous social influences on science, when at its best, science  in fact can be a self-correcting enterprise.  OC Marsh described Torosaurus and Triceratops as two separate genera.  Scannella and Horner come along a century later, with more specimens to compare, and correct Marsh’s mis-classification.  This is self-correcting science at its best.

evolution in action: ceratopsians and the paleontological evidence for evolution

September 24, 2010

Nearly everybody familiar with evolutionary theory and anti-evolution movements is familiar with the old refrain claiming that “the fossil record does not support evolution.”  However, such claims are extremely misguided, and stem from a major misunderstanding of what the fossil record does, in fact, show.  While one could pick any one of hundreds of fossil lineages to examine, we’ll look at one that most people are familiar with, the ceratopsian dinosaurs. To get a partial idea of the diversity of this group, I’ll post some pictures before continuing.

chasmosaur skull on display at AMNH

triceratops on display at AMNH

Protoceratops display at AMNH

While I’ve only shown a few specimens here, the ceratopsian lineage itself is far more diverse.  However, for the sake of ease and sanity, we’ll only look at a few key ceratopsians for our comparison.  For some basic paleontological background, ceratopsians are a Cretaceous group, thus existing towards the end of the reign of the dinosaurs.  The group as a whole was relatively successful, with a distribution throughout Western North America, Asia, and possibly Australia and South America as well.  They were herbivores, and tended to live in large groups.  In phylogenetic terms, the ceratopsians shifted from a relatively lightly built, at least partly bipedal, basal form such as Psittacosaurus, through slightly more robust forms such as Protoceratops, and ultimately towards larger forms such as Triceratops. Now I don’t want to speak in terms of “progress” or “orthogenesis” here; I’m not trying to imply that there was something inevitable about how these forms developed. Rather, it’s just the way it happened. Selective pressures pushed towards that direction, and natural selection responded by building larger, more robust forms.  Let’s take a quick look at the basic sequence:

psittacosaurus on display at AMNH, public domain pic from wikipedia

another psittacosaurus picture, this time on display in Copenhagen. Also from wikipedia.

Protoceratops on display at Carnegie Museum of Natural History, from Wikipedia

Triceratops at AMNH, from Wikipedia

With these specimens, you can get a pretty good idea of how body plans shifted during the phylogenetic history of the Ceratopsians.  However, don’t get the wrong idea here; it isn’t necessarily so that Psittacosaurus evolved into Protoceratops evolved into Triceratops. This isn’t how the fossil record works.  Rather, an organism like Psittacosaurus evolved into an organism like Protoceratops, and so on.  These specific examples show us a basic picture of the transition that occurred. They aren’t the full story.  We’re looking at over a hundred million years between us and them.  We don’t have the full picture.  Look at today’s biodiversity, and compare it to what’s available in the fossil record.  The fossil record itself is like trying to understand a person’s life by looking at a photo album, most of the pictures missing, with a picture of an individual, we’ll call him Bob, as a toddler, then as a highschooler going to the prom, then maybe as a middle-aged man with another younger man (perhaps his son?), then a funeral announcement.  We can get a basic idea of how his life unfolded, but there are many, many things that we can’t answer about his life.  This is the way the fossil record works. In order to understand how evolution operates over time, one has to look at the basic patterns visible in the fossil record. Sure, you can’t get a complete, full, exact picture of every species-to-species transition, but you can get a pretty good idea of what actually did happen in an evolutionary sense.

Another thing to note about evolution, something which is often overlooked, is the fact that evolution can, in fact, transform entire bodies as a whole. The transmutation in body plan visible in our ceratopsian lineage is a complete one, with changes in cranial anatomy (just look back at some of the ceratopsian skulls shown to see it), body size, stance, and (as we’ll look at in a minute), sacral (a fancy word for the region of the backbone that runs through the pelvis) anatomy.  What you’re looking at is not natural selection working on just one trait at a time, but rather many traits, all interacting with each other, all being tweaked slightly through the differential reproductive success of different individuals, not as distinct parts, but as a whole.  People far too often think of natural selection as acting on just one trait at a time.  Sure, it can happen like that in rare cases, but a more full understanding of evolution implies that it is the body as a whole which is acted upon by natural selection.  Yes, individual traits play key roles in reproductive success. But it is the entire body, not merely one trait, which is the agent of reproduction.  Sure, you might have a reproductive edge because you have bigger horns than your opponent.  But you ultimately get to mate because you’re a complete organism, not just one sexy part.  Now that I’ve gotten your attention by talking about reproduction, let’s look at some hips:

psittacosaurus sacrum at AMNH

If you’re having trouble finding the sacrum in this picture, look to the right of the “gastroliths” arrow, right between the little guy’s (not sure if it’s male or female, but I digress…) hind legs. It’s the bone structure shaped more or less like this: )I(

Now onto the next specimen, Protoceratops:

Protoceratops sacrum, AMNH

Look in the same place on this one, right between the hind legs. I apologize about the crappy images with the last two pictures. I took both of them a few years ago, without this purpose in mind.  But I have them, so might as well use them as examples.  Now let’s check out a Triceratops sacrum:

Triceratops sacrum, AMNH

With these three sacrums, you can see how evolution has shaped one specific body part over time. However, after looking previously at the full bodies of these dinosaurs, its much easier to view this for what it is, natural selection tinkering away at one body part as it shapes the whole body.  Regardless, this series of sacrums at least helps to illustrate the relationship between these organisms.  But keep in mind, once again, that it is the entire body that evolves, not just one part.  What paleontologists look for in the fossil record is not “transitional forms”, but “transitional features”, such as our sacrum example, when trying to define evolutionary lineages (phylogenies).  This happens precisely because superficial traits (size, weight, etc) are relatively fluid.  In order to fully understand an evolutionary lineage, it is necessary to look at specific traits which are carried throughout a sequence.  While our sacrum example is not a perfect one, we can at least roughly view how one might find such a trait.  Yes, you can see it change through the lineage, but it is also possible to build a relatively complete picture of how the sacrum has changed throughout its evolution.  Therefore, it could be used to help understand phylogenetic relationships between ceratopsians. Thus, while natural selection does operate on entire bodies, specific traits are also extremely important in defining exact evolutionary sequences.  Both angles are necessary in order to fully define an evolutionary sequence.

Anyway, let me shut up before I make this post any longer/more painful to read.  So what exactly does our quick look at ceratopsians do?  Besides being a (relatively dull) way to kill a few minutes, it also provides an often overlooked example of an evolutionary lineage.  So read up on your ceratopsian evolution (I’ve tried to stay away from the boring, terminological stuff for the sake of a quick introductory glance; Donald Prothero’s Evolution: What the Fossils Say and Why it Matters has a really good discussion of ceratopsian evolution, and would make an extremely good starting point for looking at evolution in the fossil record in general), and be ready next time someone tries to explain away the basic examples of paleontological evidence for evolution like Tiktaalik, Ambulocetus, or Archaeopteryx.  Provide an example of a full lineage such as the ceratopsians, rather than one “transitional form” in a vacuum.  It’ll provide a much stronger proof if you’re ever trying to explain evolution to someone with an open mind that doesn’t know much about the subject.

On Progress: Philosophical Ramblings on the Nature of Evolution

April 10, 2010

Let us consider, for a moment, the pinnacle of evolution.  This group of organisms builds its own cities, engages in organized labor, builds stratified, complex societies, and even practices agriculture in a sense.  I am referring to ants.  You might argue that my momentary classification of ants as the pinnacle of evolution demonstrates a level of inane stupidity on my part, but please allow me a moment to explain myself.

What would you replace ants with in my model? Most likely, you are thinking “well humans, of course”.  But why?  What justifies the classification of humanity as the ultimate pinnacle of evolution? One might argue that we are currently the “dominant” species on Earth, but “dominant” is a tricky term.  Yes, we shape the environment itself in an extremely tactile and observable manner, but even the humble stromatolite has altered Earth’s atmosphere on a global scale (by releasing oxygen early on in life’s history on Earth).  Yes, we use tools and make war with each other, but chimps do the same thing.  Is it perhaps because we are still alive today? This seems like an even worse reason to assume human superiority than the previous ones.  Given the diversity of life on Earth today, the assumption that humans are somehow the pinnacle of an evolutionary process, while perhaps a nice idea from our perspective, is not a scientifically tenable hypothesis.

Of course, I am not implying that there is nothing special about the human species when Earth’s long history is considered.  Yes, we have technological and intellectual capacities far greater than that of other species here on Earth.  Our species has achieved great things, and this should not be overlooked.  However, on the same note, our connections to the world around us must also not be overlooked.  The human species is clearly a biological phenomenon at some deep and fundamental level; we are part of nature, one with the natural world.  If one reads evolution as a progressive ladder trending inherently towards human excellence, it is far to easy to overlook our connection to the greater world around us.  How does this ideology of progress work?

The ideology of progress is actually quite simple to grasp.  If one reads evolution as a progressive process in the sense we are focusing on, then one accepts that evolution inherently operates as follows:

first, nice simple life

then, more complex life

then, even more complex life

finally, upright, bipedal, conscious organisms with social capabilities.

Of course, the fossil record mirrors this trend to an extent. We start with invertebrates, then fish, amphibians, reptiles, mammals, primates, and ultimately humans as a late arrival on the scene.  However, the ideology of progress attempts to place a directional framework around life’s evolution on Earth.  A Progressivist would argue that life somehow inherently evolves in a directional sense, ultimately tending towards consciousness.  This mindset is reflected in many popular (as opposed to academic) texts dealing with paleontology, as well as in the depiction of evolution as a tree.  First, fish appear, and then disappear as amphibians appear. Then it’s reptiles replacing amphibians. And so on.  Such a mindset is culturally constructed rather than demonstrated by scientific data. In the model of evolution as a tree, humanity is ultimately placed at the top and center of the tree, with other lineages, such as reptilia, as side branches.  The message in such a presentation is clear: humans are the most important species on Earth.  Ernest Haeckel’s own evolutionary tree is perhaps the most beautiful illustration of such an idea. The illustration is public domain, so I’ll upload it in a minute, but here’s the wikipedia page where I borrow the image itself from. Anyway, here’s the image:

Haeckel's tree of life

However, Haeckel’s tree of life is extremely problematic. Species do not stop evolving once a more “advanced” group appears on the scene.   When amphibians first evolved during the Devonian, fish did not disappear, never to be heard from again. Nor did they stop diversifying.  Indeed, evolution still shapes new piscine permutations, even today.  If we were self-aware fishes rather than mammalian in nature, perhaps we would shape our evolutionary ladder in such a way that our fishy heritage would be the defining trunk of the tree of life, with humans off on some side branch of their own. Of course, we are not really fish, we are humans. Therefore, we understandably view our own species as the most important product of evolution (as demonstrated by Haeckel’s tree).  Such an anthropocentric model of evolution, while understandable, is not scientific in nature.

In fact,  Darwin rejected the ideology of progress inherent in Haeckel’s tree.  Darwin preferred the analogy of a coral, rather than a tree.  On p. 25 of the B Notebook (available here), Darwin states that “The tree of life should perhaps be called the coral of life, base of branches dead; so that passages cannot be seen.” Darwin was contemplating  tree-like models, but his tree, or coral, was inherently nonprogressive (image from here):

Darwin's tree, or "coral" of life

Note that in contrast to Haeckel’s tree, Darwin’s own illustration (although superficially tree-like) has no obvious pinnacle. Branches “A”, “B”, “C”, and “D”, each branch off in their own separate direction, with no single branch occupying an obviously central position on top of a well-defined trunk.  Thus, no progress inherent in Darwin’s own illustration of how natural selection works.

But what does this all mean? Is there a reason for my posting of these beautiful yet archaic images?  Trees, branches, corals, and progress…who cares?  This line of inquiry is useful for multiple reasons.  First, Darwin’s coral and Haeckel’s tree offer a wonderfully clear illustration of how one’s own biases can influence one’s science.  While Darwin’s coral suggests natural selection as a wholly non-progressive enterprise, inherent in Haeckel’s tree is his own, and indeed our own, anthropocentrism.  Haeckel’s tree places humans exactly where most of us view ourselves, at the top of the ladder and central to all life on Earth.  In Haeckel’s tree, non-human lifeforms are portrayed as inherently “lower” than humans. In Darwin’s coral, we are relegated to one branch of the larger model, diverging from other lifeforms in a similar manner to that of Haeckel’s tree, but merely away from other lifeforms rather than inherently upward.

So what?  Darwin drew corals to illustrate evolution but Haeckel drew trees. This split, in itself, signifies a far greater split within human society.  Most mainstream Western religious belief systems uphold a view of humanity similar to that presented in Haeckel’s tree.  Humans are presented as beings “Created in God’s image”, at the pinnacle of all life on Earth.  Darwin’s coral, being non-progressive in nature, seems to contradict these belief systems.

However, is such a contradiction between evolution and religious belief really necessary?  While religiously inspired anti-evolution movements see such a contradiction as inherent and deadly to either evolution or religion (choosing, of course, evolution as the ideology to reject), is such a contradiction really there?  Not necessarily.  While some evolutionary biologists, such as Richard Dawkins, are ardent atheists, others, such as Kenneth Miller, are devoutly religious.  As I argue in Gould’s Hopeless Monster, evolutionary theory can, in fact, co-exist with religious belief.  However, the two magisteria DO overlap in some cases, forcing some level of compromise in the zones where this overlap occurs in order to maintain coexistence.

Of course, if one wants to truly accept all implications of modern science, then religious beliefs will often end up shifting to accommodate science in these contested zones.   But this is not to imply that science disproves God.  Indeed, God is a supernatural hypothesis outside the magisteria of science; one cannot scientific prove or disprove the existence of the supernatural.  What science can and must do is to follow the available evidence where it leads in search of natural explanations for natural phenomenon.  So is Darwin’s coral or Haeckel’s tree the correct model for the diversity of life? The fact that the history of life on  Earth has followed a relatively contingent path of development over the past few billion years lends credibility to Darwin’s coral rather than Haeckel’s tree.

But what does this mean for religious belief? Surprisingly, not as much as one might initially think.  While such a model suggests that we are deeply tied to the web of life surrounding us, it does not necessarily exclude the existence of God.  As much as one might argue that a rejection of the ladder of progress somehow “lowers” the significance of human existence, why is such a statement necessary? One could just as easily argue that such a position rather elevates the position of non-human lifeforms, perhaps focusing on the unity of all lifeforms as part of God’s creation, if one wanted to debate the issue in theological terms.  Of course, such a discourse, while influenced by science, is not in itself scientific in any sense, since science cannot, by nature, answer theological questions dealing with the supernatural.

Now, moving away from the question of religion, let’s finally focus on the implications for science as a whole.  The ladder of progress is heavily embedded within the scientific community, even though, as we have seen, it is a non-scientific concept.  In fact, Michael Ruse (1996) has published an entire book, Monad to Man: the Concept of Progress in Evolutionary Biology, focusing on the subject.  If you’re at all interested in the question of progress after reading this post, I strongly suggest checking it out.  Regardless of whether we embrace Darwin’s coral or Haeckel’s tree, our choice has major implications for how we view life as a whole.  If we are to embrace Haeckel’s tree, then consciousness is likely to be the end result of an evolutionary programme, suggesting that self-aware life is likely to be ubiquitous, or at least fairly common throughout the universe.  If we are to rather embrace Darwin’s coral, then consciousness is likely to be far rarer in the universe.  So perhaps ironically, while Darwin’s coral seems to de-emphasize the importance of human life here on Earth, it may prove to be foundational to the importance of human existence in the cosmos as a whole.  If evolution does not necessarily trend towards consciousness, and if it is therefore plausible to argue that we are one of only a few (if not the only) “conscious”, self-aware species in the universe as a whole, then that is an intriguing thought.  If we are indeed organisms of an exceedingly rare nature within the cosmos as a whole, then perhaps such a plausibility is worth contemplating.

Ray Comfort, A Creationist’s worst nightmare

December 5, 2009

Well I’m back in the swing of things after celebrating Thanksgiving with the traditional holiday consumption of everybody’s favorite derived theropod, and I finally got my hands on the Ray Comfort version of Darwin’s Origin of Species. I could hardly wait to read through it!  Comfort added a fifty page Creationist introduction to Darwin’s classic text and handed copies out for free at multiple college campuses in the United States.  I figured I might as well share the wealth, and discuss the introduction on here!

Comfort’s introduction begins with a short biography of Darwin.  This biography is surprisingly good, compared to the rest of the text. Perhaps this is because this segment was “borrowed” (I’ll be nice here and won’t use the term “stolen”) from Stan Guffey.  A story on the NCSE website today described these allegations, which if true, are pretty bad.  Here’s the NCSE story.  Here, we’ll focus on the parts that are definitely (as far as we know for now) written by Comfort.

First, (9-13), Comfort describes alleged “difficulties” for evolutionary theory caused by DNA.  Comfort implies that DNA is so complex that it necessitates the creative actions of a creator.  However, Comfort’s stance assumes that given an extremely unlikely event A, that A, or an event equally as unlikely as A, would never happen.  This is patently false.  If you have 1 in 23521532352535235 odds (randomly selected number) of something happening, this means that one of 23521532352535235 possible outcomes WILL occur.  If you were to claim that probability based arguments rule out the possibility of DNA being formed without Divine intervention, you would be committing a logal fallacy, as demonstrated here. Just because the odds of something happening are extremely low does not mean that it is impossible for said thing to happen.  This line of reasoning also assumes that DNA came into existence in one fell swoop, without steps along the way.  However, we do have models which do not work in this way.  For example, Robert Hazen (among others) has suggested that amino acids could have grown and replicated on a crystalline framework (i.e. on rocks).  The nice thing about this model is it provides a mechanism for explaining the left-handed bias among amino acids in life.  This line of logic also ignores the relatively common nature of amino acids; they pepper comets like candy in a 5-year-old’s bedroom.  Given such models, the odds against DNA coming into existence are far smaller than one would think if one were to argue that DNA came into existence all at one magic moment.

Even if the DNA argument put forth by Comfort (that DNA necessitates a Creator), that does not undermine the validity of Darwinian natural selection.  Darwin’s theory does not seek to explain the origin of life; it can, by nature, work only on already existing lifeforms.  Therefore, the origin of DNA does not seem to be a problem for Darwinian theory, even if one could not offer a plausible scientific explanation.  Therefore, Comfort either misunderstands evolution or is intentionally conflating Darwinian theory with abiogenesis.  Either way, doesn’t bode well for the strength of his introduction!

We’ll move on to something that actually could be problematic for evolution, if Comfort’s allegations were true.  Comfort implies (13-14) that the fossil record does not support evolution, since there are, as he would have usbelieve, no transitional forms present in the fossil record.  He obviously hasn’t gotten the memo on this one:

While I include an image of one of the well known ancestral forms of modern whales (this guy on display at the Smithsonian Natural History Museum), I could have just have easily included one of hundreds of other known “transitional forms”.  However, according to Comfort, we don’t KNOW that whales evolved, so this doesn’t count as a valid transitional  form.  Comfort also heavily emphasizes two fraudulent “transitional forms”, including the classic favorite among antievolutionists, Piltdown Man.  Of course, a few fraudulent finds do not discredit an entire science.  Comfort is building strawmen here, and is apparently hoping that his audience does not do enough further research to catch on.

Comfort also makes the glaring error of calling the recently published fossil Ida “THE” ‘missing link’.  Comfort’s statement implies that scientists are working with only one transitional form, or “missing link”.  It’s an obviously flawed semantic statement, and also an extremely scientifically naive one.  We have hundreds of transitional forms and features.  Why do we absolutely NEED Ida to be “the missing link”?  As it is, there is currently debate going on over the implications and relationships of Ida. However, the semantic problem is not Comfort’s alone.  At least part of the blame can be placed squarely on the shoulders of the press.  However, Comfort should have done his homework on this one first.  For further discussion about Ida, click here.

Next (18-20), Comfort discusses the Cambrian Explosion, claiming (18) that “virtually all the major animal forms appeared suddenly without any trace of less complex ancestors“.  This is utterly and patently wrong.  Many paleontologists today describe the Cambrian “Explosion” as actually occurring relatively slowly.  Even if it was “sudden” in geological terms, by “sudden”, paleontologists mean happening over hundreds of thousands or a few million years.  Comfort’s rhetoric would imply that it happened in a few days.  Comfort therefore misrepresents scientific data on the tempo of the Cambrian “explosion”.  Comfort also ignores, or is not aware of, the presence of “simpler” organisms pre-dating the Cambrian “Explosion”, such as the small shelly fauna. The small shelly fauna DO provide some possible ancestral forms to organisms that Comfort would have us believe arose out of nowhere. Therefore, Comfort once again  drops the ball when trying to discuss science.

Since I’ve demonstrated the lack of scientific validity of Comfort’s claims, I will not waste any more of your time or mine describing  Comfort’s further scientific errors. We’ll move on to his historical ones.  First, p. 31, Comfort implies that Darwin is responsible for “Social Darwinism”, when anyone that knows about the history of scientific racism will immediately tell you that this type of mentality pre-dated Darwin’s work by decades.  Any attempt to blame Darwin for the misuse of his work in this pre-existing racist construct is rediculously flawed.  Once again, Comfort has either failed to do his research, or is attempting to obscure the real story.

Along these lines, Comfort makes a big fuss over Darwin’s views on race.  Apparently, we should be appalled when Comfort tells us of Darwin’s belief that Black people are somehow less intelligent than Whites.  I am appalled, but for the wrong reasons (in Comfort’s eyes).  First, Darwin was a racial moderate for his day (see an earlier post on my blog that essentially debunks any attempt to describe Darwin as a racist).  Second, Darwin actually learned taxidermy from a freed Black slave.  Therefore, it is likely that Darwin viewed Blacks as both intelligent and able.  Comfort then makes a fuss about a statement made by Darwin that implies that women are less intelligent than men.  After quoting (relatively out of context) Darwin’s reasons for marriage, Comfort makes the following statement :

Darwin believed that women were not as competent as men, and less intelligent than men, but they were better than a dog.” (35).

So wait a minute….Comfort is condemning Darwin because he was a British Victorian man?  Of course Darwin is going to seem racist and sexist by today’s standards, especially when selectively quoted.  But Comfort is attempting to judge Darwin by today’s standards, rather than the standards of the Victorian Era.  Darwin lived 200 years ago; even a child should be able to see the underlying problems with Comfort’s approach here.  It both saddens and disappoints me to see such an error made by a grown man, and even worse, get overlooked by editors.

Next (35-37), Comfort attempts to blame Darwin for Hitler’s actions.  There are numerous problems with this approach.   First, even if Hitler did warp Darwinian theory to fit his own agenda, this does not mean that Darwinian theory is inherently genocidal.  Hitler also utilized inherently Christian terminology at times.  Does this mean that Christianity is the real cause of Hitler’s agenda?  Of course not!  So even if Hitler did utilize Darwinian theory, you cannot implicate the theory in Hitler’s crimes.

However, Hitler’s views on evolution were inherently non-Darwinian in many ways.  Hitler sought a biological basis for a Nazi master race, one that pure Darwinian theory could not provide.  Hitler utilized “Social Darwinism”, that old racial pseudoscience that predates Darwinian theory at a far deeper level than he utilized pure Darwinian theory.  If Hitler was so sold on evolutionary theory, then why did the Nazis ban the writings of Ernest Haeckel, the prominent German champion of Darwin? Seems like the Nazis had some issues with pure Darwinian theory.  This thought is confirmed in the article previously linked in this paragraph.  In a quote from a Nazi document on banned books, the following statement is included as a criterion for banning texts: “writings of a philosophical and social nature whose content deals with the false scientific enlightenment of primitive Darwinism” (again, from here).  While it is difficult to grasp what the text means by “primitive Darwinism”, one can assume that it likely includes Darwin himself, being the founder of Darwinism.  It seems that yet again, Comfort has failed to do his homework.

Comfort then tells us that Darwinian theory is embraced by atheists, and implies that it is an inherently athiestic idea (see, for example, pp. 39-41).  However, Comfort fails to tell us about such Christian evolutionists such as Kenneth Miller.  One wonders why…

Finally, we get to the most entertaining part of the introduction.  I have to admit that I never expected to open a copy of the Origin of Species and find a passage warning me about the fires of hell.  Yet this is exactly what one does find near the end of Comfort’s introduction.  However, we are lucky enough to have an explanation from Comfort himself on how to be saved from Hell.  Here’s what he tells us:

To receive the gift of eternal life, you must repent of your sins (turn from them), and put on the Lord Jesus Christ as you would put on a parachute—trusting in Him alone for your salvation. (49)”

Then, to conclude his introduction, Comfort presents the following paragraph:

Please don’t toss this book aside.  If it’s been helpful to you, pass it on to someone you care about—there’s nothing more important than where they will spend eternity.  Thank you for reading this. (49)”

The implications of this statement are clear.  After Comfort devotes nearly 50 pages to telling us why Darwinism is a racist, atheistic, bankrupt science, Comfort is then offering us salvation through his specific interpretation of Christianity.  Comfort is implying, either intentionally or unintentionally, that accepting evolution will likely lead one into the fires of Hell.  One might be tempted to quote Judge John E. Jones III of Kitzmiller v. Dover (“breathtaking inanity”) in reaction to Comfort’s introduction. Comfort has misrepresented both science and history at the most basic level in an attempt to push his own religious views on others.  Worse yet, he has tarnished one of the most important and elegant texts in the history of scientific thought in the process.  While Comfort’s claims do nothing to undermine the strength and validity of Darwin’s work, they do  show an inherent disrespect both for science and for religion.  Comfort forces a wall between evolution and Christianity, which in Comfort’s model, cannot be breached.  However, as I have demonstrated in Gould’s Hopeless Monster, while science and religion may need to make compromises in order to coexist, they ultimately can coexist in some fashion.  Comfort’s model rejects this possibility.  What worries me most is that some people might not research beyond Comfort’s claims, and as a result may actually believe him.  Luckily, the National Center for Science Education has provided protection against Comfort’s patently false claims in the form of a bookmark (available here to print out).  Share one with somebody you care about, especially if they have recieved a copy of the Ray Comfort edition of the Origin of Species.

One Long Argument, one hungry blogger

November 19, 2009

In anticipation of the 150th anniversary of the publication of Darwin’s Origin of Species (November 24th; mark your calendars!), I figured I would address evolutionary theory.  The concept of evolution is one of the simplest in science, yet is often misunderstood.  While searching for a good illustration of how evolution works, I realized that I was hungry.  Heading out to the lobby, I checked the vending machines for something to eat:

 

Noticing the presence of M&Ms in the machine, I had an idea. M&Ms come in different colors; i.e. they have a built-in source of variation.  I opted for the ones with peanuts (E7), put in my dollar, and got a package.  Upon returning to the room, I opened the package of M&Ms, and laid them out to display the degree of variation within said population of M&Ms:

After examining the population, I realized that there was a level of variation such that we have a healthy population, with some traits being rarer than others.  Blue, Green, and Orange were designated as “common”, Brown as “uncommon”, and Red and Yellow as “rare”.  So we have a population with variation.  How does said population evolve?

Certain traits (in this case colors) are advantageous, while others are disadvantageous.  If a predator likes to eat red things, the red M&Ms are in trouble.  There is only one representative of that variety in our population, and this blogger does like red M&Ms.  Therefore, we have a disadvantageous trait, and said variety is removed from the gene pool, i.e. it goes extinct.

While the red variety goes extinct, the blue, green, yellow, and orange varieties go on living happily, and breeding (unfortunately I cannot make M&Ms reproduce…bear with me).  Eventually, some event occurs that alters some portion of our population (be it a behavioral change, mutation, etc).  In this case, we’ll use a reference to 2001 A Space Odyssey.  A monolith pops into the scene.  The blue and orange M&Ms are attracted to it.  The other M&Ms run away:

 

 

If you are not familiar with the scene this is referencing, it is available here.  So the Blue and Orange varieties gain some sort of differential survival advantage (call it “intelligence”) from contact with the monolith.  We’ll say that the monolith is radioactive and caused rapid mutations within the Blue and Orange genomes; we’re not looking at long periods of time here, so I’m taking a leap here and increasing the speed of our demo.  The Blue and Orange varieties chase off the other varieties of M&Ms due to their inherent differences (we’ll say through a mountain pass), and then return to their own region.  A landslide (or in this case a giant screw falling in the middle of the picture) blocks off the pass, separating the blue and orange varieties from the other varieties:

After separation, you have two separate varieties, which compete amongst themselves, and evolve along separate paths.  This is called allopatric speciation:

Eventually, an earthquake or something of the sort removes the geographic barrier, and the populations mix once again:

If the two populations have been separated long enough, and evolved along different enough lines, then they will be able to coexist without competition.  If this is the case, populations will stabilize between the two without much competition:

 

OK, but what has this little thought experiment demonstrated about evolution?  Evolution through natural selection, at its most basic level, requires variation within a population.  When dealing with living organisms, this variation is provided by genetic mutation.  Genetic mutation is pretty much random in nature.  However, certain mutations are favorable for survival, other mutations are unfavorable, and some are neutral.  Darwin’s model of natural selection is based on a competition for resources; certain individuals will just be better able to compete for resources.  These individuals are the ones that will tend to leave the most offspring.  Natural selection works by weeding out unfavorable mutations and increasing the population of organisms with favorable mutations.  Mutation is random.  Natural selection is not.  Natural selection will inherently favor those organisms that have traits which give them an edge for survival.  In our M&M analogy, if predators like to eat red M&Ms, then red M&Ms will likely be rarer (or go extinct quicker) than other varieties.  If some gazelles run faster than others, and the slow ones are the ones that generally get eaten by lions, then natural selection will gradually increase the average speed of the gazelle population as a whole.
Within our M&M analogy, we saw a rapid “Poof”-style evolutionary shift in which some M&Ms drastically changed form after coming into contact with a monolith.  I do not mean to imply some sort of magical evolutionary process in which a bird suddenly hatches from a lizard egg; that’s saltationism, and saltationism is wrong.  However, given the right conditions and environmental pressures, evolution can happen relatively quickly.  When you separate one large population into two smaller ones (our screw-landslide), you decrease the size of the gene pool, and thus enlarge the potential impact of a given mutation.  As such, relatively small populations can often change relatively quickly.  In some cases, once the separated populations come back into contact with each other, they have evolved along separate enough paths that they do not directly compete with each other, allowing for the coexistence of both groups.  In other cases, both groups do still directly compete with each other.  In these cases,  natural selection once again weeds out certain individuals, and allows others to prosper.

As demonstrated, evolution through natural selection is an extremely simple process. Some organisms are better adapted than others, and these well-adapted organisms will tend to reproduce more often, eventually taking over the population. However, as demonstrated through our brief, rough look at allopatric speciation, natural selection is not the only force involved in controlling the evolution of life on Earth.  Environmental factors also can play a major role.  Barriers between populations are also important.  Meteor impacts and other mass extinction events can drastically shift the course of evolution on Earth.  But can evolution explain the diversity of life on Earth?

Given the long period of time for which the Earth has existed (approximately 4.6 billion years), we certainly have had enough time to evolve the diversity of life on Earth.  While some have raised questions (generally pseudoscientific in nature) about the ability of evolution to explain the origin of the eye, or transitions between major groups of animal, for example, these objections are weak.  While we have a working mechanism for evolution, and a huge amount of evidence in support of the idea that life on Earth is the result of a long, drawn-out process of evolution, there is no mechanism given for these arguments against evolution.  No defined laws which would forbid the evolution of the eye.  No tactile reason to believe that one could not evolve a bird from a dinosaurian ancestor, or an amphibian from a fish.  The evidence is clear, and the process is as elegant as it is simple.  Evolution happens.

 

neat source; James Hall obituary

October 30, 2009

If you’ve been following my blog for a while, you may remember my “In the Footsteps of Giants” post.  In it, I mention New York State Geologist James Hall.  Interestingly enough, his New York Times obituary is accessible online (click here, PDF format).  Hall was an interesting figure, and his obituary sheds more light on his life.  Hall worked closely with the likes of Charles Lyell and Louis Agassiz, and published some noteworthy works of his own (especially focusing on the geology of New York).  The obituary is short, and well worth spending a minute or two to read.

Gould’s Hopeless Monster

October 30, 2009

I’m back, after a brief hiatus (getting back into the swing of college again).  Sorry about disappearing off of the radar recently.  I’ve been doing some pretty intense reading focusing on the relationship between science and religion lately, and this paper is the result: a critique of Stephen Jay Gould’s concept of Non-overlapping Magisteria. It’s pretty long, but seems enjoyable enough to me:

While Stephen Jay Gould’s thesis of non-overlapping magisteria (NOMA)[1] has some merit, it is as a whole highly problematic.  Although Gould does allow for some minor contention at the boundary between science and religion[2], his contention that science deals with only empirical questions and religion deals only with moral and spiritual questions is deeply flawed.  While science is, at its core, an empirical process, scientific ideas often have far-reaching consequences which can deeply impact religious thought.  Therefore, although the claim that science and religion are constantly at war with each other is nothing more than a myth[3], there are contested zones in which science and religion are inherently in a state of conflict.  These contested zones run deeper than NOMA implies, and therefore are a problem for Gould’s construct.  This essay will explore these contested zones through the interaction between evolutionary theory and revealed religion. Due to the asymmetrical public treatment evolution has received from different religious groups, this discussion will focus mostly on the interaction between evolutionary theory and Christianity.  However, contested zones are present between evolutionary theory and non-Christian religions as well, as will be demonstrated later through the example of Kennewick Man.  In conclusion, it will be demonstrated that Gould’s concept of non-overlapping magisteria is inextricably flawed, and should be discarded.

While pre-Darwinian discussions of evolution[4] certainly did have theological implications, for the purposes of this essay, these discussions will be bypassed here due to the nature of the texts.  Pre-Darwinian theories of evolution tended to be Progressive in nature, focusing on the gradual improvement on life on Earth, eventually culminating in the development of White European Christians.  Darwin rejected this model, and sought to distance himself from these authors.  As such, Darwin refrained from using any derivation of the term “evolution” until the last word in On the Origin of Species.  This text is where we will begin our discussion.

Darwin’s thesis, which states that life evolves mainly through natural selection, is an elegantly simple one.   In a given population, different organisms will exhibit slightly different traits.[5] Some of these traits will provide their owners with a distinct survival advantage.  Other traits will prove problematic to their owners.  These differences lead to differing rates of reproductive success.[6] Over long periods of time[7], this process will drastically alter the features of members of the given population.  In essence, natural selection acts as an agent of design, shaping the features of life on Earth.

As such, Darwinian natural selection is a direct refutation of Paleyan natural theology. Darwin was thoroughly aware of this fact; in fact, as Darwin notes in his autobiography, he studied Paley’s Evidences of Christianity, and Moral Philosophy as a student at Cambridge[8] (and Natural Theology later in life). As a young man studying to become a minister, Darwin was deeply impressed with Paley’s work, which was deeply influential in Christian thought at the time.  Therefore, it is not surprising that the Origin of Species, in a sense, can be read as a refutation of Paley.

In fact, certain passages in Darwin’s Origin of Species directly allude to Paley’s work.  Consider, for example, the following passage:

To suppose that the eye, with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest possible degree.  Yet reason tells me, that if numerous gradations rom a perfect and complex eye to one very imperfect and simple…can be shown to exist…then the difficulty of believing that a perfect and complex eye could be formed by natural selection, though insuperable by our imagination, can hardly be considered real.[9]

This statement serves as a direct refutation to Paleyan theology, as demonstrated below (from Paley’s Natural Theology):

Were there no example in the world of contrivance except that of the eye, it would be alone sufficient to support the conclusion which we draw from it, as to the necessity of an intelligent Creator.  It could never be gotten rid of; because it could not be accounted for by any other, supposition, which did not contradict all the principles we possess of knowledge[10]

Paley continues to describe the perfection of the eye in a way similar to which Darwin does.  However, while Paley viewed this perfection as necessitating an intelligent Creator, Darwin viewed natural selection as sufficient to explain the origins of the vertebrate eye. This comparison illustrates the profound theological implications of On the Origin of Species.  Through the lens of natural theology, the Creator is viewed as one which is responsible for every detail of an organism.  Through the lens of natural selection, the Creator becomes one which created the first few organisms and who allowed life to evolve as a result of natural processes.

This radical re-definition of humanity’s place in nature created a major contested zone between science and theistic religion.  Le Conte[11] notes that evolutionary theory, like the heliocentric model before it, might be seen to pose a threat to religious beliefs. However, Le Conte implies, as with the heliocentric model, religious belief will come to encompass evolutionary theory. According to Gould[12], Pope John Paul II’s October 22nd, 1996 speech to the Pontifical Academy of Sciences would seem to confirm this hypothesis. Ruse 2001[13], however, notes that the Pope’s endorsement is valid only if the basic tenets of Catholic faith are not compromised.  Therefore, if an aspect of evolutionary theory contradicts Catholic faith, then it must be rejected. This hesitance towards evolution is understandable. Accepting evolutionary theory as part of a religious framework fundamentally alters the structure of that belief.  Daniel C. Dennett has called evolutionary theory a “universal acid” that alters everything that it touches[14].  This is as true with science as it is with religion.  Evolution itself becomes a contested zone, with atheists such as Richard Dawkins and theists such as Kenneth R. Miller both claiming a consistency between evolutionary theory and their own personal belief systems.

What is evident, even within Miller’s work, is that evolutionary theory does drastically alter religious belief.  Miller’s vision of God is one who created human life through natural evolutionary processes, one who could have created our species in a more direct fashion, but chose not to[15]. This view of God, while consistent with evolutionary theory, is drastically different than a classical view of God in which God created humans out of dust in His own image.  In order for evolutionary theory to co-exist with religious belief, the religious belief system in question must be fundamentally altered.  While Miller’s God[16] is consistent with evolutionary theory, it is necessary to accept certain Biblical passages (for example Ch. 1 of Genesis) as allegorical rather than factual.  The religious belief in question must make compromises in order to incorporate evolutionary theory.  As implied by Ruse 2001 (as mentioned above), there is only so much room in which Catholicism is able to move to incorporate evolution. Eventually, evolutionary theory will find itself at odds with Catholic belief[17]. Therefore, it is clear that science and religion do not inhabit totally separate spheres. Contested zones exist wherever scientists attempt to study topics classically relegated to the religious realm, for example where humanity came from.  Gould’s model of non-overlapping magisteria fails to incorporate this logical problem, and is therefore incomplete.

The contested zone between science and Christianity is even greater among literalist Christian groups such as the Seventh Day Adventists and Baptists.  These groups accept a 6,000 year old Earth on which life was created in six literal days[18]. Seventh Day Adventists such as George McCready Price and Ellen White published books that criticized science that did not fit within a literal interpretation of the Bible.  Price went so far as to attempt to reinterpret the geologic column using Noah’s Flood as a creative mechanism, so as not to necessitate long periods of time for the formation of the geologic record[19]. In the mid-20th century, individuals such as John C. Whitcomb and Henry Morris would continue the pursuit of Price’s model of flood geology[20]. Whitcomb and Morris’ work would spark the growth of a relatively significant Young Earth Creationist movement within the United States, one which attempts to deny evolutionary theory for religious reasons.  It is clear that to these groups, evolutionary theory and religious belief cannot coexist.  Acceptance of evolutionary theory or an old Earth directly contradicts a literal interpretation of Genesis, and therefore becomes a religious issue[21].  In this instance, it seems that evolutionary theory and religion cannot peacefully co-exist.  Here, the science itself is altered[22] in an attempt to force it to conform to religious expectations.

Disagreements between evolutionary theory and religion are not solely a Christian issue.  The case of Kennewick Man offers an alternate issue, featuring a contested zone between Umatilla religious belief and science.  The study of skeletons such as Kennewick Man is seen by archaeologists as an attempt to understand where the first people to colonize the Americas traveled from.  The remains of Kennewick Man are drastically different (and older) than the remains of modern Native American peoples.  Although Kennewick Man is now suspected to be most closely related to the Ainu of Japan[23], the original press releases on the skeleton suggested that Kennewick Man was “Caucasian” in derivation[24]. Regardless of the ancestry of Kennewick Man, any non-North American interpretation directly contradicts the Umatilla creation story[25], which implies that their ancestors have always inhabited the North American continent.  In cases such as this, there is no legitimate compromise between scientific data and religious belief.  Either the ancestors of the Umatilla always inhabited North America, or they didn’t.  Both sides cannot be correct.  Here, science and religion are not occupying separate realms; both the scientific and religious interpretations are dealing with the same exact question.  In cases such as this, Gould’s concept of NOMA breaks down completely.

In many cases, science and religion are inextricably linked.  For example, Noble 1999 describes the deep level to which religious belief has influenced Western technological and scientific growth.  While millenarian Christian beliefs deeply influenced the exploration of the Americas,[26] later human exploration in space would also be infused with Christian belief[27]. Both projects of exploration were couched both in scientific and religious terms.  Newton himself viewed his scientific achievements as being deeply tied to his religious beliefs[28]. Much like Kenneth Miller, prominent evolutionary theorist R.A. Fisher viewed evolution as deeply linked to his Christian faith.  However, deeply linked to Fisher’s belief system is the notion of Progress.  In Fisher’s case, it was the need for human action to further the human condition[29].

While science can be positively linked to organized religion in some settings, in other settings, science can be deeply tied to atheism.  Granted, by definition, science is not meant to favor one religious belief system over another.  However, some philosophers and scientists such as Richard Dawkins (2006) and Daniel Dennett (2006) have tried to forge a link between science and atheism.  Both authors view religion as an ultimately explainable natural phenomenon that does not ultimately require any type of God.  To these authors, religion is seen as an evolved response to external pressures.  Cziko (1995) offers a classic example of this type of view.  Cziko focuses on the link between rice cultivation and religion in Bali, and describes the link in terms of cultural evolution.  Under this type of model, the Balinese religious beliefs are important for rice cultivation because they help explain when to plant and harvest crops[30].

It is at these moments, within these contested zones, which the alleged separation between science and religion collapses.  Gould is correct in stating[31] that science and religion do in fact collide at the border between the two “magisteria[32]”. However, while Gould does note that science and religion can interact, he misses the main point.  Gould develops his position such that science deals solely with empirical fact and that religion deals solely with questions of moral meaning and value[33]. Gould’s model ignores situations in which religious belief has a seemingly direct impact on scientific matters[34].  It also overlooks instances (such as Cziko 1995) in which scientific theory attempts to explain away religious beliefs.  Instances such as this provide a classic instance of a contested zone.  The realm of science is, in these instances, delving directly into religious questions.  Granted, while attempts put forth by the likes of Dawkins and Dennett to use science to prove atheism are philosophically flawed[35], areas where science does seem to explain the basis of a given religious belief does seem to contradict Gould’s model. At some level, the scientific explanation of the belief in question will likely directly contradict the religious explanation of the belief.  This presents a situation in which science and religion do directly overlap.

Scientific thought also has direct influences on religious belief.  As previously demonstrated, Darwinian natural selection, as a direct refutation of Paleyan design, revolutionized religious thought.  In the case of Roman Catholicism, evolutionary theory directly altered such thought.  While one could argue that this alteration resulted from an interaction between science and religion, it is better defined as a direct overlap between the two.  First, in an attempt to support NOMA, Stephen Jay Gould explains that Catholics can accept evolution as long as they believe that the soul is divinely created. However, while Gould (through a Pope John Paul II quote) notes[36] that one cannot directly scientifically observe the spiritual, he overlooks a key issue.  Ruse 2001[37] notes that an acceptance of evolution by John Paul II directly contradicts earlier Catholic belief, which necessitated a monogenist[38] view of humanity. While merely accepting evolution does not cause problems for Catholics, a deeper analysis of the consequences of such an acceptance clearly does.  To fully accept evolution is to reject the monogenist view, which in turn calls into question the concept of Original Sin.  The rejection of this view also raises questions about the most basic of all Christian beliefs, that of mankind being created in God’s image.  If humans evolved, then can one truly say that humans were created in God’s image?  Ruse 2001 argues that Pius XII viewed monogenism as a key component of Christian belief,[39] and notes that Pius XII addressed this topic in Humani Generis. While Gould 1999 does address Humani Generis,[40] he misses this point. The concept of monogenism is one in which evolutionary theory and Catholic theology directly collide, and yet Gould fails to acknowledge it.  This failure raises questions with regards to the accuracy of Gould 1999.

Gould also fails to sufficiently address religious belief systems other than Roman Catholicism (although Gould does admirably admit a lack of background with some religious belief systems, especially Eastern ones).  Gould implies that “Creationism” is a small-scale American fundamentalist Christian institution[41].  However, this statement is false.  Christian Creationism is not a solely American institution; Christian Creationist groups exist in Australia, England, and elsewhere[42]; Jewish[43], Muslim[44], and Native American Creationist[45] groups also exist.  Therefore, Gould’s picture of religion as a whole is a flawed one.

Gould fails to adequately address the fact that different religious belief systems interact with science in different ways.  Gould creates a false dichotomy in which science either does not overlap with religion at all or is completely anti-scientific in nature.  The first group is assumed by Gould to incorporate the majority of religious believers, with the latter occupying a small fringe group.  However, this description creates a dreadfully oversimplified picture of the boundary between science and religion.  Some believers (such as Roman Catholics) are pretty open to science.  Other groups (such as Seventh Day Adventists and Baptists) often try to alter science into something that is consistent with their faith.  Some groups merely reject science that contradicts their beliefs.  Given the vast number of different religious sects globally, it seems nearly impossible to draw one distinct line separating science and religion.

Gould’s concept of contingency[46] also seems logically inconsistent with NOMA.  Contingency implies that evolution itself is a totally random process.  Replay life’s tape a thousand times and a thousand different results will be produced.  This concept implies that there is nothing special about human existence.  Taken to its logical end, contingency implies that humans are the result of accident and luck.  This in itself is a spiritual statement.  The concept of contingency inherently crosses Gould’s artificial boundary between science and religion.  Contingency addresses a direct question of value. It seeks to answer a key religious question, one which focuses on our very identity as a species.  The concept of contingency follows Gould’s reading of the fossil record to its logical end.  However, by arguing that humanity is the result of a series of accidents, Gould crosses the boundary between science and religion established in Gould 1999, therefore rendering the boundary a false one.  Science, like religion, can be used in an attempt to answer questions of a moral or value-based nature.  Religion, like science, often does delve into traditionally scientific questions.  Therefore, Gould’s concept of non-overlapping magisteria fails at the most basic level.

Gould’s argument is flawed in that it creates a false dichotomy between science and religion.  As demonstrated through the previous discussion of Darwin and Paley, scientific discoveries can fundamentally and drastically alter religious belief systems.  When scientific fact and religious belief collide, there are multiple possible reactions. In some cases, no overlap (and no conflict) is present[47].  In other instances, where overlap does occur (such as with evolutionary theory and Catholicism[48]), one or both sides make compromises[49] to avoid conflict.  In the case of religiously-based anti-science movements, science that is seen to conflict with religious belief is openly rejected on the grounds of such a conflict.  While Gould[50] seeks to imply that these movements are fringe groups and that no such conflict exists, clearly there is some level of overlap between religion and science. While this overlap can result in either conflict or compromise, its very existence calls the validity of Gould’s NOMA into question.

While Gould’s NOMA model is deeply flawed, this does not mean that science and religion cannot coexist.  However, a more sophisticated model is necessary to address the boundaries between science and religion.  Gould argues that science and religion occupy wholly separate realms, which occasionally collide, but never overlap.  Gould relegates religious belief to a realm of morality and science to a realm of empiricism.  However, this division is overly simplistic.  Science can and does create morally troubling questions (such as the debate surrounding the creation of the atomic bomb).  However, religion is not the only possible pathway to moral choice.  Scientific data plays a major role in weighing the costs and benefits of any morally taxing scientific question.  The political elements operating within a society also play a key role. The picture of science as a solely empirical force with religious belief picking up the moral slack is a deeply flawed one.

Religion also delves into the empirical realm.  If religion were a solely moral force, there would be few (if any) contested zones between science and religion.  However, the presence of these contested zones suggests that religion is more than a moral force.  As has been shown, scientific discoveries do often create contested zones between religion and science.  This suggests that religion itself is somehow concerned with empirical questions.  Of course a distinction must be drawn here, such that the scientific questions that concern religion tend to be questions of ultimate meaning and causality (such as the question of evolution).  Since both science and religion seek to answer questions of this nature, these spaces are where the overlap between the two is greatest.  At these points, there is no clean separation between religion and science, at least in the sense that Gould’s NOMA model predicts.  The question, for religion, becomes not only a spiritual one but also a physical one.  Either God created humanity out of dust (or some other method depending on the religious group at hand) in its current state, or humans evolved through natural selection.  One cannot have it both ways.

Therefore, revisions are necessary if Gould’s model is to work at all.  NOMA is a useful concept, but a deeply flawed one.  The idea that religion and science can coexist peacefully is a good one.  There is much merit to this inference.  However, if progress is to be made in the dialogue between science and religion, the idea of completely separate spheres must be discarded.  Science and religion are both human socio-cultural constructs.  Both are presented as pathways to truth.  They are not mutually exclusive; for example, Darwin likely didn’t give up his Christian faith because of his work on evolution, but rather as a result of the logical problem of evil[51] and the problem of hell[52].  Evolutionary theorists such as Fisher and Miller openly accept both Christianity and evolution.  It is therefore obvious that science and religion can coexist.  However, compromises must be made.

The magisteria of science and religion do occasionally overlap.  Therefore, any revised look at the two subjects must incorporate this fact.  A simplistic Draperian conflict thesis is obviously flawed, but some level of heated interaction between the two magisteria is likely.  The contested zones between science and religion are where any thorough focus on the interplay between these two subjects must begin.  Science and religion can both be easily understood in a vacuum, but when the two are combined, the picture becomes convoluted. While Gould describes science and religion as two wholly separate magisteria that can interact but never overlap, a better model is one which allows for some overlap between science and religion.  However, given the complexities of religious philosophy (such as the myriad belief systems on a global level) and science, it is impossible to define exactly where such overlaps will occur.  To make such a comparison, one must compare scientific fact with religious belief on a sect by sect basis.  Rather than denigrating religious groups that reject science as radicals outside of the norm, a useful model will incorporate these groups such that it will be possible to outline exactly where scientific thought overlaps with religious faith in such cases.  Perhaps Gould’s greatest gaffe is oversimplifying the interaction between science and religion; since there is no single monolithic religion, but rather myriad different belief systems, such a simplification is fatally flawed.  For science and religion to peacefully coexist, compromises must be made within the contested zones between the two, or one or the other must be partially or totally rejected.  Gould’s model of NOMA does not predict or incorporate such an outcome.  Therefore, non-overlapping magisteria, while an interesting thesis, is fatally flawed, and should be drastically altered or rejected.

Works Cited:

-Cziko, G. Without Miracles: Universal Selection Theory and the Second Darwinian Revolution. MIT Press, Cambridge, 1995.

-Darwin, CR. The Origin of Species. Barnes & Noble Books, New York, 2005. 6th Edition, original year of publication 1872

-Darwin, CR. The Autobiography of Charles Darwin. Barnes & Noble Books, New York, 2005. Original year of publication 1887.

-Darwin, CR.  Autobiographies. Penguin Books, New York, 2002.  Originally published 1903

-Dawkins, R. The God Delusion. Houghton Mifflin Company, New York, 2006

-Dennett, DC.  Darwin’s Dangerous Idea: Evolution and the Meanings of Life.  Simon & Schuster, New York, 1996.

-Dennett, DC. Breaking the Spell: Religion as a Natural Phenomenon. Viking Penguin, New York, 2006

-Draper, JW. History of the Conflict Between Religion and Science. 8th edition, D. Appleton and Company, New York, 1878

-Egan, T. Tribe Stops Study of Bones That Challenge History. National Report, the New York Times, Sep. 30, 1996.

-Gould, SJ. Wonderful Life: The Burgess Shale and the Nature of History. WW Norton & Company, New York, 1989

-Gould, SJ. Non-overlapping Magisteria. In Leonardo’s Mountain of Clams and the Diet of Worms: Essays on Natural History. Three Rivers Press, New York, 1999 p. 269-283

-Le Conte, J. Evolution and it’s Relation to Religious Thought. D. Appleton And Company, New York, 1890.

-Miller, KR.  Finding Darwin’s God: a Search for Common Ground Between God and Evolution. Harper Perennial, New York, 2002

-Noble, DF.  The Religion of Technology: The Divinity of Man and the Spirit of Intervention.  Penguin Books, New York, 1999

-Numbers, RN. Introduction to Galileo Goes to Jail and Other Myths About Science and Religion. Harvard University Press, Cambridge, 2009 p. 1-7

-Numbers, RN. The Creationists: From Scientific Creationism to Intelligent Design. Harvard University Press, Cambridge, 2006.

-Paley, W.  Evidence of Design (from Natural Theology), in Readings in Philosophy of Religion. Ed. Eschleman, A. Blackwell Publishing, Malden, 2008. p. 144-145

-Pope John Paul II.  “Truth Cannot Contradict Truth”.  October 22nd, 1996 address presented to the Pontifical Academy of Sciences.

-Quammen, D. The Reluctant Mr. Darwin: An Intimate Portrait of Charles Darwin and the Making of His Theory of Evolution. Atlas Books, New York, 2006

-Ruse, M. Monad to Man: The Concept of Progress in Evolutionary Biology. Harvard University Press, Cambridge, 1996

-Ruse, M. The Evolution Wars: A Guide to the Debates. ABC-CLIO, Santa Barbara, 2000

-Ruse, M. Can a Darwinian be a Christian?. Cambridge University Press, Cambridge, 2001

-Strong, EW.  Newton and God. Journal of the History of Ideas, Vol. 13, no. 2, p. 147-167, April 1952

-Schnee, K. Make No Bones About It (The Tech. Online Edition.  Vol. 119, Issue 52: October 22, 1999) http://tech.mit.edu/V119/N52/col52schne.52c.html accessed 2/25/2009

-White, AD. A History of the Warfare of Science With Theology in Christendom. V 1 and 2. D. Appleton and Company, New York, 1897

-Zimmerman, LJ. Public Heritage, a Desire for a “White” History for America, and Some Impacts of the Kennewick Man/Ancient One Decision. International Journal of Cultural Property, 2005, 12:2:265-274


[1] Gould 1999 p. 269-283.  In a nutshell, NOMA states that science and religion need not conflict since they occupy different realms.

 

[2] Gould 1999 p. 274

[3] This idea is known as the conflict thesis. As noted by Numbers 2009 p. 6, this thesis, presented in such texts as Draper 1878 and White 1897, is deeply flawed.

[4] Such as those ideas presented by Lamarck, Chambers, and Erasmus Darwin

[5] Variation.  We now know that variation is a result of genetic mutation.  However, the source of variation in evolution was demonstrated after Darwin’s death.

[6] After all, if an organism has a trait which makes it difficult for it to survive, it is unlikely to leave many offspring.

[7] If selective pressures remain steady

[8] Darwin 1887 (2005) p. 20

[9] Darwin 1872 (2004) p. 207-208

[10] Paley 1855 (2008) p. 145

[11] Le Conte 1890 p. 262

[12] Gould 1998 p. 270, 272

[13] p. 74-75.

[14] Dennett1995 p. 63

[15] Miller 2002 p. 243-245

[16] And the Roman Catholic God in general; Miller is Roman Catholic.

[17] At points which Catholic dogma is directly called into question.

[18] Ruse 2000 p. 110

[19] Numbers 2006 p. 90-104

[20] Numbers 2006 p. 211-215

[21] This is not to say that evolutionary theory or geology is in any sense “religious”, but rather that it contradicts the beliefs of some Christian sects.

[22] At which point it becomes wholly unscientific in the eyes of the mainstream scientific community.

[23] Schnee 1999

[24] Zimmerman 2005

[25] Egan 1996

[26] Under a description of the New World as a New Eden.  See Noble 1999 p. 21-33

[27] Noble 1999 p. 115-142

[28] Strong 1952

[29] Ruse 1996 p. 301-303

[30] Cziko 1995 p. 152-157

[31] Gould 1999 p. 274

[32] To borrow Gould’s terminology

[33] Gould 1999 p. 274

[34] See, for example, Fisher’s Progressivism.

[35] Science cannot ultimately disprove the existence of God.  God’s existence is a supernatural question, which means that science does not have the ability to answer it one way or the other.

[36] Gould 1999 p. 278

[37] p. 75-76

[38] In this situation, a view in which all humans are directly descended by Adam and Eve, who were, according to this interpretation, two literal individuals. It is worth noting, however, that evolutionary theory is strongly consistent with a more basic form of monogenism which merely states that all living humans are ultimately derived from the same ancestral stock.  Darwin even indirectly affirms such a framework in On The Origin of Species, where he states that “[l]ight will be thrown on the origin of man and his history” (Darwin 2005 [1872]).  In this case, the term “man” is singular, implying a singular ancestry for all of humanity, rather than separate origins for each race of human.  This statement, in itself, stands as an open rejection of polygenist thinkers such as Agassiz.

[39] p. 75

[40] See p. 275-280

[41] p. 270-271

[42] See Numbers 2006 p. 399-432

[43] Numbers 2006 p. 427-431

[44] Numbers 2006 p. 420-427

[45] For example Umatilla Creationists, this essay

[46] 1989 p. 288-289

[47] Due to a definition of science such that science cannot answer questions dealing with supernatural causation, if religion is defined such that it does not overlap with scientific thought, then the two can coexist without an issue. However, such definitions of religion do not always exist.

[48] Christian monogenism being threatened by evolution

[49] Such as John Paul II stating that Catholics can accept evolution as long as they believe that God created the soul.

[50] 1999 p. 270-271

[51] As expressed through the deaths of two of his children (Quammen 2006 p. 118-119)

[52] Darwin devotes one of the shortest, most pointed paragraphs (Darwin 2002 [1903] p. 50) in his entire body of work to the idea that his “Father, Brother, and almost all [of his] best friends will be everlastingly punished” merely for not accepting the Christian belief system:

“And this is a damnable doctrine.”

Along with the deaths of his children (especially Mary in 1842 and Annie in 1851), the problem of hell seems to have been a major component of Darwin’s loss of faith.  However, it is worth noting that Darwin was most likely never an atheist, but rather likely died as an agnostic.  Therefore events that occurred during Darwin’s life (and the nature of Christian belief itself), and not evolution, caused Darwin’s loss of faith.