Tuesday, May 31, 2005

Evolutionary Theory or Evolutionary Theology?

This was one of the last papers that I wrote during my undergraduate program at Berea College. It was for BIO 494, a required capstone class for all Biology majors which focused on evolutionary theory.

Evolutionary Theory or Evolutionary Theology?
Fact and myth-making in the biological sciences.

I. Different narrators, different narratives

In August of ’99, following hot on the heels of a controversial Kansas Board of Education vote to remove evolution from that state’s science curriculum, Stephen Jay Gould authored an impassioned essay which alleged that this was not simply a decision about educational standards, but a blow to the very foundation of human society and progress:

“Let me suggest that, as patriotic Americans, we should cringe in embarrassment that, at the dawn of a new, technological millennium, a jurisdiction in our heartland has opted to suppress one of the greatest triumphs of human discovery” (Gould 1999).

In order to mollify his perhaps questioning readers, those “…Americans of goodwill [who] might be excused for supposing that some genuine scientific or philosophical dispute motivates this issue,” Gould (1999) assured them of three fundamental matters. The first was that no corresponding controversy surrounding the acceptability of evolution exists in other nations of similar culture, demographic, and progressivism (i.e., “the West”). Secondly, he bore witness to the “fact” of evolution. And finally, Gould asserted that science is no threat to religion and philosophy, but rather seeks a separate but equal status to these disciplines.

As his faculty position at Harvard alone might attest, Gould was a highly respected evolutionary scientist. Readers who perhaps were not aware of his credentials were informed of them by the endnote attached to his essay. What most of his readers, and perhaps even Gould, may have missed however, was the thin ice he skated on in his attempt to reconcile two seemingly at-odds, foundational myths(1) underlying Western culture: the myth of human purposefulness and the myth of scientific knowledge. On the one hand, certain interests within Western society have advanced the notion that humans are a creation of the divine, governed by and accountable to the laws of our Creator first and foremost. Competing interests have informed us that humans lack inherent purpose, and are a provisional accident of nature. Despite his best efforts to play nice and lubricate relations between these rival interest groups, Gould fell decidedly with the latter. What he conveniently neglected to address in his essay is how two opposing truths about how the world works and how human behavior should be governed can be peaceably reconciled, or at least co-exist.

This dissonance between competing narratives should be of significant concern to biology students as we endeavor to more fully understand the “fact” of evolution, the narrative which forms the basis of our discipline and which we may, like Gould, be called upon to defend in the classroom, the courthouse, and the halls of Congress. In order to do so, we should certainly familiarize ourselves with the facts, the mechanisms, and the paths of evolution as they are currently held. Yet we must also understand the history of the idea of evolution, and the institutional processes which have legitimated and replicated it. Through such an understanding, we are more apt to avoid telling the little white lies that Gould is guilty of in his essay and likely in much of the public relations work that he performed for the scientific community. What are the “lies”(2) that inform Gould’s assertions? They are numerous, but three in particular are of concern in the telling of the evolution story:
• “Good science” requires adherence to a specific process, and those who abide by it are able to accurately observe and explain phenomena.
• This scientific process, or method, has established the “fact” of evolution, and there is no legitimate scientific or philosophical challenge to this “fact.”
• By not including evolution as a core component of science curriculum, we are undermining human society and progress(3) (Schuster 1995).
Oversimplifications based upon an uncritical understanding of how science works obfuscate several important elements of the development of evolutionary theory. A retelling of the evolution story is necessary in order to more clearly understand how the theory has arrived at its current status. Through this retelling we might also gain clearer insight into the ongoing evolution-creationism debate and broker a more honest compromise between the parties involved.

In order to do so, several important, underlying issues must be addressed. The first of these is the Charles Darwin narrative. Darwin, at least as he is popularly portrayed, is the archetype of the scientist-hero; and his theory of natural selection is one of the “great ideas” to which all scientists aspire. In what ways do modern values and knowledge tint our retelling of the past and lead us to distort the image of Darwin, the formation of his ideas, and the character and intelligence of his opponents?

Another important issue is the development, or evolution, of evolutionary theory. To what extent was Darwin’s theory “true” compared to the evolutionary theory of today, and in what ways was the formation of his theory shaded by ideological rather than informational differences with modern science? How has the theory’s relationship to “fact” changed over time, and what are the observed phenomena and natural processes which tend to favor evolution’s version of natural history? Through what institutional processes has the theory of evolution grown from a fringe idea to become the very basis of the discipline of biology, and in what ways does its replication within the pedagogy of natural science resemble dogmatism?

And finally, to what extent is the theory of evolution “necessary” to the institution of science? Is the grassroots assault on evolutionary theory really, as Gould asserted, an attack on the foundations of human society?

II. The Charles Darwin narrative

“As the earth and ocean were probably peopled with vegetable productions long before the existence of animals; and many families of these animals long before other families of them, shall we conjecture that one and the same kind of living filaments is and has been the cause of all organic life?”
-Darwin, Erasmus. 1794.

While nearly every science textbook can be counted upon to have a short, opening section which discusses the history of the given field, it may be that the history of science is better left to historians than to scientists. As historian Herbert Butterfield (1965) pointed out, people often examine the past with a particular set of objectives of which they may or may not be aware. Such analysis does not provide a genuine mediation between past and present, but instead serves to vindicate a particular idea or institution in light of currently held beliefs. If history is to be truly understood, it must be examined in its completeness, its complexity, and with the goal being to, as much as is possible, contextualize a given historical moment rather than to seek out its commonality with the present (Butterfield 1965). The history we are presented with in the science classroom often does just the opposite. Its stories are abridged and simplified, and the objective, at its most harmless, appears to be cutting to the chase so that students can move directly on to the important stuff—i.e., the currently-held facts, mechanisms, and underlying theory (Pigliucci 2002).

Unfortunately, it appears that such abridgement at times also serves a more pernicious purpose--that is, propagandizing. An example of the propagandistic retelling of science history can be seen in the film Darwin’s Dangerous Idea. With its use of mainstream film convention(4), its transparent efforts to identify Charles Darwin and his allies as the story’s heroes and those who denied or questioned evolution as villainous, the filmmakers present an entertaining contest between those who sought to further the progress of humankind and those who hindered it. As with numerous other tellings of the evolution story, we are given very little sense of the shortcomings of Darwin’s own ideas and the merits of his critics. Instead, his critics are portrayed as less intelligent, less objective, and/or somehow less able to see the truth of evolution sitting clearly before them.

Similarly, a shallow retelling of history often leaves us with the impression that rational people, when presented with two clearly differing ideas, based their decisions solely upon the merits of the ideas rather than any mediating social factors operating within the scientific community itself. In his retelling of the Darwin narrative, Massimo Pigliucci (2002) provides significant detail of the extent to which Darwin and his colleagues waged a conscious publicity campaign in support of their theory. These efforts included keeping track of who their opponents were, encouraging the publication of reviews and letters favorable to their ideas, seeking strategic positions of influence for themselves and their allies, and even establishing a new scientific magazine with the purpose of appealing to younger scientists. Yet Pigliucci (2002) ultimately falls into the same trap as other pseudo-historians of science, proclaiming that Darwin’s public relations campaign “…does not explain why evolutionary theory became accepted in scientific circles. It did because it was good science.”

One aim of this sort of storytelling is to present a particular model of how science works. That model asserts that scientific knowledge is based upon sound, universally-applied process and objective facts, and that it is therefore impervious to social forces. The implication of the model is that scientific method offers the only legitimate path to truth discernment, and that anything “less” than scientific methodology cannot be relied upon as accurate. Further, since truth-discernment is obviously in the best interests of humankind, anything which stands in its way is a regressive force on society (Schuster 1995). This model of how science works depends upon an abridged, oversimplified version of history in order to stand. The deeper we go into the historical record and the more we work to contextualize the lives and ideas of the past, the more we muddy the water and undermine the myth of scientific knowledge; hence the expedience to science propagandists of a shallow investigation of the past. Pigliucci (2002) bemoans the tendency of scientists to overlook history, claiming that a deeper understanding of the past will help us to understand the importance of scientific process. He is correct in that assertion, but may yet be unaware of the Pandora’s box of new questions and challenges to commonly-held assumptions in which such an inquiry may result.

So what are some of the important details that are missing from the abridged version of Charles Darwin’s formulation of his theory of evolution, and why are these important today? What was perhaps most interesting (and dangerous) about Darwin’s idea was that it unified a number of pre-existing challenges to the creationist(5) worldview which had for so long shaded Western scientific (and popular) thought. These challenges had been some time in the making, and none of them originated with Charles Darwin (Bowler 2003). They included, among others, the age of the Earth, the elasticity of the natural world, descent with modification, the view of humanity as a component of the natural world, and an insistence upon “scientific” explanation for natural phenomena (Bowler 2003). The history of each of these challenges is rich and worthy of their own documentation, notwithstanding their influence upon Charles Darwin and his contemporaries. But even a cursory glimpse at any one of them helps to broaden our understanding of the formation of Darwin’s theory.

It is oft-noted that Charles Lyell’s two-volume “Principles of Geology,” which accompanied Darwin aboard the Beagle, challenged prevailing theories regarding the age of the Earth (Volpe and Rosenbaum 2000). What is less often discussed is the ongoing debate during that time between uniformitarian geologists and the burgeoning science of thermodynamics (Hull 1988). Proponents of thermodynamics placed the Earth’s age somewhere between 20-200 million years old; old enough to pose a significant challenge to the creationists’ estimation of a few thousand years, but not nearly old enough to satisfy the needs of uniformitarians such as Lyell and his followers (which came to include Darwin). In the middle years of the 19th century, there seemed to be significant data supporting and challenging both theories, and both would themselves be subject to considerable modification with time (Hull 1988; Bowler 2003). During the latter half of the nineteenth century however, the views of leading physicist Lord Kelvin and his fellow proponents of thermodynamics were favored by many physicists and geologists. Kelvin’s ongoing reductions in his estimation of the Earth’s age contributed to significant undermining of natural selection’s efficacy given its reliance upon incredibly slow, gradual change (Bowler 2003).

Another challenge to creationist philosophy that is rich with complexity is the debate around the fixity of the natural world. There existed a wide diversity of ideas with regards to this issue (some of them dating to the pre-Christian society of ancient Greece), such as the assertion that all life was exactly as God created it and that the natural world lacked the capacity to alter itself, the idea of a “chain of being” which arranged all organic matter into a hierarchy, and the view that the adaptive form many organisms hold with regard to their environment is evidence of divine wisdom (Bowler 2003). At the time, there was no easy distinction between those who were influenced by this line of thinking and those who weren’t. Yet Darwin’s age witnessed the beginnings of the unraveling of this paradigm, as one-by-one, chinks began to accumulate in the armor of those believing in a fixed natural world. In response there was a significant effort to save the paradigm, and natural philosophers fell along a wide spectrum with regards to their response.

While the field of geology had already begun to pose some intriguing questions as to the age of the Earth, the slowly uncovered fossil record was also presenting researchers with evidence of curious forms of life previously unseen by humanity. How was it that such a significant portion of God’s creation had inexplicably gone missing? And what of the discoveries, such as Darwin’s in Argentina and Galapagos, that revealed extinct organisms with a striking resemblance to the living (Hull 1988)? Jean Baptiste Lamarck, whose ideas are often cited in order to contrast them with Darwin’s, recognized that organisms undergo physiological change in response to their environment. Lamarck endorsed, as did a growing number of his contemporaries, the idea of inheritance of these acquired characteristics as a means of explaining how organisms changed over time. Yet he remained committed to the stability of species; i.e., he did not believe that new species came into existence through the modification of existing ones (Hull 1988). Further, his ideas about the underlying forces which brought about these changes reflected a bias towards a deeply hierarchical arrangement within nature.

Georges Cuvier, a respected zoologist at the Museum of Natural History in Paris and an adversary of some of Lamarck’s ideas, held even stronger views with regards to the stability of species. While he acknowledged that certain species had gone extinct over time, he viewed dissonance with the species’ environment solely as a cause of extinctions rather than a driving force for modification. Cuvier envisioned an Earth that in its original form had contained a vast repository of species, this repository having been depleted over time as a result of sporadic yet severe catastrophes (Hull 1988). Yet despite his allegiance to a strict, largely immutable natural order, Cuvier is often credited with developing the earliest, most widely-accepted challenge to the idea of a “chain of being” through his categorization of all life into four distinct embranchements.

David Hull, in his work Science as a Process (1988), designates another interesting response to the fossil evidence as a school of thought he refers to as idealism. The central theme that unifies this movement is the belief that “archetypes” of physiological form can be found in nature. Indeed, comparative anatomy of living and extinct organisms does reveal striking resemblances. Modern science explains these resemblances via convergence, the action of similar selective pressures on a wide variety of distantly-related organisms, and homology, the accumulation of distinctive modifications to organisms which share a common ancestor in their recent past (Volpe and Rosenbaum 2000). For the idealists, modification of archetypes explained both the unity and diversity of nature, and this idea seemed initially quite compatible with Darwin’s formulations. T.H. Huxley, often referred to as “Darwin’s bulldog,” was both an early convert to evolution and a student of leading idealist thinker Edward Forbes; Huxley and many others did not initially see a conflict between some notions within idealism and evolution (Hull 1988). Even for Darwin, some aspects of idealism clearly worked, and in his Origin he seemed to avoid openly confronting idealism, as he would later, referring to “unity of type” as “interesting” and a “law” of biology. For at least some of the idealists however, their observation of archetypes did not so easily amount to evidence for Darwin’s theory of natural selection, which sought to explain a causation for these similarities (Hull 1988). Idealism presented an important factual observation, but one which, at least on the surface, could be seized as evidence by both those advocating for descent with modification and those arguing for divine creation. Eventually, open ideological warfare would be waged between some of the idealists and those who aligned themselves with Darwin. While in retrospect Darwin’s explanation of unity of type seems much more robust, Hull (1988) also points out that Darwin’s group had some important sociological advantages over the idealists as well, such as a greater uniformity of ideas and a central figure to rally around. These differences contributed to Darwin’s ability to ignore attacks by individual idealists as his own following grew.

The pattern that begins to emerge as we examine the myriad characters who involved themselves ferociously in the scientific debates of Darwin’s day is that while many of them contributed to the tremendous change in worldview which characterizes their age, no one of them held a complete set of views which corresponds directly to those held today. Lyell, Lamarck, Cuvier, the idealists, all sought to reconcile their observations, and those of their colleagues, with varying aspects of the theoretical zeitgeist of their era. No one thinker pulled a uniquely new idea out of thin air, and no one clearly pulled ahead to cross the finish line first, because the finish line itself is only a convention, produced in hindsight, that is used to wrap history up into a tidy bundle. Even the primary protagonist of this story, Charles Darwin, relied upon already-existing ideas in the formulation of his theory, some of them ideas which have been soundly rejected with time. Although the theory of evolution by natural selection that Darwin and his colleagues advanced seems to more clearly and cohesively represent modern views than anything else we’ve inherited from that period, a closer examination of Darwin’s theory reveals a number of problems which have forced modern thinkers to rescue Darwin’s evolution from becoming yet another theoretical relic.

III. A Theory in Crisis?

Just as the retelling of the period leading up to the formation of Darwin’s theory has been oversimplified, so too has the period between 1859 to the present. The “Darwinism” that modern biology students inherit in the science classroom is not the same as that originally advanced by Charles Darwin and his allies. Further, while Pigliucci (2002) declares that the “end of the scientific debate” around evolution occurred in the 1890s, and Gould (1999) asserts that there is no “genuine scientific or philosophical dispute,” in reality, Darwin’s theory has been and remains subject to numerous legitimate criticisms, alterations, and gaps in efficacy.

The burgeoning field of genetics is remaking the biological sciences, if not our entire society. As we gain greater historical perspective on the latter half of the 20th century, we will acknowledge this fact even more fully than many of us do now (Ridley 1999). No aspect of the biological sciences will remain untouched by this genomic revolution, including Darwinism. In 1859, Charles Darwin and most of his contemporaries had very little understanding of the heritability of traits, despite the fact that it played such an important role in his theory. To surmise that there is a heritable basis to physical traits and that the environment judges these traits and hence affects the rate at which they are reproduced is one thing, but understanding how these traits are passed on and manifest from parent/s to child is quite another. For Darwin, this phenomenon was explained via a process he referred to as “pangenesis” in his 1868 publication Variation of Animals and Plants under Domestication. There are two important pieces to the pangenesis theory: the first is the source of phenotypic variation, the second is the means through which these variations are passed between generations (Bowler 2003).

There was not such a clean break between Lamarckism and Darwinism as we are often led to believe. Where the overlap is most apparent is in Darwin’s ideas about the source of variation, which are clearly Lamarckian. Like Lamarck and many scientists of the day, Darwin accepted the idea that changing environmental conditions act upon the reproductive system of the parents, thereby leading to variation. Darwin differed from Lamarck in that he didn’t believe that these changes were inherently purposeful, but that they were essentially random, to be tested and sorted by the environment (Bowler 2003). One of the strongest 19th century proponents of natural selection, August Weismann, did not accept these Lamarckian remnants. In his now famous experiments in which he chopped off the tails of mice in generation after generation, Weismann sought to disprove Lamarck’s (and Darwin’s) notion that changes to the parents could lead to variation in the offspring (Bowler 2003). Weismann instead proposed a theoretical substance known as “germ plasm” which was passed between generations without parental modification. This theory was essentially Weismann’s attempt to save natural selection from its degenerate Lamarckian relics, and resembles more closely the accepted view of transmission within modern genetics; yet it was also subject to significant controversy at the time. In order to distinguish between true Darwinians like himself and those extremists such as Weismann who found natural selection alone to be a sufficient explanation for species change, George John Romanes coined the term “neo-Darwinian” towards the end of the 19th century (Hull 1988).

The other important component of the heritability question is transmission. Regardless of how variation occurs, how is it passed between the generations? Darwin’s pangenesis theory proposed the existence of “reproductive elements” which comprised the next generation and were derived from the parents’ various tissues. He referred to these elements as “gemmules,” and believed that they would “bud off” from the different tissues of the parents, circulate via the bloodstream, and concentrate in the reproductive organs; they would then mix together within the offspring to determine its overall phenotype (Hull 1988; Bowler 2003). This explanation is now referred to as “blended inheritance,” and has been thoroughly rejected in hindsight. Even before the advent of modern genetics, theorists contemporary to Darwin found serious flaws in the idea of blended inheritance. Scottish professor of engineering and colleague of Lord Kelvin, Fleeming Jenkin, was an early critic of blended inheritance, pointing out that it could not be reconciled with natural selection because each new and advantageous change would be lost in the general dilution of descent (Bowler 2003; Hull 1988; Ridley 1999).

The rise of a coherent discipline now recognizable as genetics (originally organized around Mendelian principles) led to sustained, credible challenges to Darwinism, and it became clear to proponents of natural selection that serious modifications to Darwin’s theory would be necessary if it were to avoid “eclipse.” William Bateson, premier British proponent of Mendelism and coiner of the term genetics, led the assault on Darwinism. His 1894 book Materials for the Study of Variation argued that the elements of inheritance are not only particulate (rather than blended, as Darwin maintained), but that this phenomena severely limits the power of Darwin’s version of natural selection (Bowler 2003; Ridley 1999). Indeed, a growing number of Bateson’s colleagues began to abandon natural selection’s explanation for speciation entirely, instead proposing that new species arose directly via mutation rather than small, gradual change mediated by selection pressures. Hugo De Vries’s (one of the original “rediscoverers” of Mendel’s work) “mutation theory” fell at least partially along these lines, and was widely advanced as an alternative evolutionary theory throughout the early decades of the 20th century (Bowler 2003). Thomas Hunt Morgan, another profoundly important character in the nascent field of genetics, early on took an even harder line than De Vries in his rejection of Darwinism. The strengths of De Vries’s version of evolution were that it solved the problem of intermediates (i.e., they largely didn’t need to exist) and fast-tracked evolutionary change such that it could be achieved within the sort of time-scale required by Kelvin’s thermodynamics.

While these challenges never succeeded in completely demolishing the theory of natural selection, they did bring it seriously into question; so much so that some authors were led to refer to the late 19th/early 20th century as the “eclipse of Darwinism” and the “deathbed of Darwinism” (Bowler 2003). Ironically, genetics has proven to be a stronger ally than enemy to the theory of natural selection. The intense debates around the mechanisms of variation, heritability, and speciation that erupted as a result of the new science not only forced the adaptation of Darwinism, it also eliminated its theoretical opponents; early geneticists were successful, for instance, in eliminating any possibility of Lamarckism as a reasonable explanation for these phenomena (Bowler 2003). As the field of genetics grew and became more experimentally-based, researchers recognized that the vast majority of mutations are not species-forming, but mostly random and inconsequential. This changing concept of mutation, combined with a retooling of some of Darwin’s ideas about heritability, ultimately led to what has been referred to as the “modern synthesis.” The synthesis brought armistice to the short but brutal conflict between Darwinists and Mendelians; notably important contributors to this effort included Ronald Aylmer Fisher and his work Genetical Theory of Natural Selection in 1930, J.B.S. Haldane (who cited the famous example of “industrial melanism in the peppered moth”), Theodosius Dobzhansky and his Genetics and the Origin of Species, and Julian Huxley, grandson of T.H. Huxley and author in 1942 of Evolution: The Modern Synthesis (Bowler 2003; Hull 1988). It was Huxley who both coined the term “modern synthesis” and who referred to the period leading up to the synthesis as the “eclipse of Darwinism.”

If the courtship between genetics and Darwinism was rocky, the honeymoon has been generally (though not entirely) more convivial. Modern genetics continues to both support certain aspects of Darwinism and to challenge others. Since the synthesis, which resulted not only in a general acceptance of modified Darwinism but also in elimination of its rivals, newly-uncovered understanding of the inner workings of the genome has been interpreted through the lens of natural selection. The universality of the nucleotide-based “language of life” found in the DNA has, for instance, been viewed as strong evidence for descent from common ancestry, a core component of evolutionary theory (Volpe and Rosenbaum 2000). Yet other insights into the genome have brought about some troubling questions; troubling, that is, if one holds to rigid, Darwinist-based explanations. As geneticist Steve Jones (2000) points out, a full explanation of the structure and function of genomes may well require movement beyond Darwinism. This supposition makes sense given that The Origin of Species predated gene theory by half a century and that Darwin’s model of heredity has been completely discarded.

Genetics has not been the only science-based hindrance to traditional Darwinism. Credible, if imperfect, critiques of Darwinism have been raised by biochemists who claim to observe irreducible complexity in some structures (Denton et al. 2003). Additionally, the idea of slow, continuous change advocated by Darwin has been at least partially replaced with a punctuated equilibrium, in which speciation occurs over relatively short time periods interspersed between much longer periods in which very little lasting change occurs (Volpe and Rosenbaum 2000). Ironically, Gould (along with Niles Eldredge) played a prominent role in this modern alteration of classical Darwinism, a fact he strangely seems to overlook in his assertion that no “genuine scientific or philosophical dispute” exists with regards to evolution. Numerous significant questions have also been raised which challenge traditionally-held views on the mechanisms of natural selection. Motoo Kimura’s “neutral theory of evolution” has brought into question how tightly selective pressures regulate genetic changes (Bowler 2003; Volpe and Rosenbaum 2000). In addition, the discovery of periodic catastrophes throughout Earth’s history has introduced a significant degree of randomness into the development of life. The implications of such randomness are not only that fitness can take a complete backseat to a species simply finding itself in the wrong place at the wrong time, but also that the uniformity that Darwin’s theory relies upon may not be quite so reliable. Finally, traditional Darwinism depends upon the action of selective pressures on the individual, but modern genetics suggests that these pressures might often work at the level of the genes, or, as is seen in insects, at the colony level, resulting in significant differences from selection pressure exerted at the level of the individual organism (Jones 2000; Keller and Reeve 1999).

Finally, significant challenges have been leveled at the supposedly scientific formulation of the theory of natural selection. It is an acknowledged fact within even the shallowest retellings of the Darwin narrative that the formulation of his theory was at least somewhat influenced by the economic paradigm of Victorian society. More specifically, the writings of Thomas Malthus are said to have influenced Darwin’s realization of a great “struggle for existence” resulting from limited resources and an ever-expanding population (Volpe and Rosenbaum 2000). What is less often discussed is that while Malthus’s ideas still hold true in a general sense—i.e., resources do seem to be finite and most species do not appear able to consciously limit their own reproductive capacity—the predictions stemming from these generalizations have not held. These predictions have not held with regards to humanity because human cooperation and specialization has allowed for the development of agricultural technologies which have increased food production to a level commiserate with human population growth. We hence observe the power of cooperation—a somewhat foreign concept perhaps to those residing in laissez faire England--as a moderating force upon outright competition. Might cooperation play a similar role in other species as well? E.O. Wilson has proposed a theory of “mutualistic symbiosis” which would seem to assert the powerful role of inter-species cooperation in softening the strict competitiveness of traditional Darwinism. There exists a wide array of opinions amongst historians of science as to just how strongly Darwin was affected by Malthus, and how much it matters, but that his theorizing was affected by the overall socio-political zeitgeist that existed in Victorian England is in little doubt (Bowler 2003).

The purpose of such a cursory examination of these challenges and amendments to the ideas that Darwin advocated is not to throw the baby out with the bathwater, but simply to acknowledge that they exist. Some proponents of Darwin’s ideas argue that there is an essential theoretical core which has remained intact from 1859 to the present. If that is the case, this core has only been maintained as a result of significant paring down and modification of the ideas proposed by Darwin and his early allies which are not useful to the modern biologist. As historical analysis shows, the path that Darwinism has followed from 1859 to the present has been circuitous at best, and certainly not linear; yet this lack of linearity does not make modern evolutionary theory any less true. Similarly, pointing out that Darwin, and really all scientists, are influenced by the cultural context in which they live does not nullify their ideas per se. Indeed, some would argue that the modifications and challenges Darwinism has been subjected to actually reflect the strength of science; that is, its self-correcting mechanism which brings us progressively closer to knowing the truth about the world we inhabit. It seems schizophrenic however to argue two sides simultaneously—scientific findings are either always tentative or they’re not; scientific processes are either always influenced by social forces or they’re not—these are mutually exclusive claims.

Yet this schizophrenia is evident even in statements by some of science’s most erudite defenders. When Gould (1999) says on the one hand that “science does not deal in certainty,” but then insinuates the fact of evolution as “a proposition affirmed to such a high degree that it would be perverse to withhold one’s provisional assent,” what does he mean? Is he referring to the evolutionary theory of 1859, the post-synthesis evolution, and/or the evolution as currently held after his own attempts at revision? Are the more modern challenges to traditionally-held Darwinism, many of them levied by thoughtful, educated, credentialed scientists, somehow perverse? And what is provisional about the assent modern biology students are asked for with regard to evolution, especially when presented with such a narrow historical understanding of how it has arrived at its current position? Hull (1988) provides an interesting anecdote resulting from his ongoing interviews with scientists; when asking them whether “…science is provisional, that scientists have to be willing to reexamine any view that they hold if necessary?” he received unanimous affirmation. Yet when he later asked “Could evolutionary theory be false?” he received not-so-straightforward responses and many replies that no, evolutionary theory could not be proven false.

Once more it should be noted that this argument is not one about the complete unreliability of evolution for understanding some aspects of the natural world; even many of its critics would not go that far. Nor does this argument seek to deny science’s overall efficacy in shedding light on the empirical world around us; we would be hard-pressed to find anyone making that claim. This argument is about how science operates versus how many scientists claim that it operates—both to themselves and to the wider public.

IV. Science and Progress

Assumptions are a dangerous necessity. In a world increasingly jam-packed with competing stimuli, powered by biological machines built for sifting through tremendous amounts of information and quickly transforming it into coherency, it is unlikely that we could exist in a state of permanent tentativeness with respect to our understanding of the universe around us (Pigliucci 2002). Yet tentativeness seems to be called for, as nearly every declarative statement which one could make about the world has built-in assumptions which are certainly not universally agreed upon. Often, the best way to consider an argument is to discern what its underlying assumptions are—if one or more of those assumptions do not hold, then the argument is suspect. The tacit story that we get from Gould, and from many scientists, is a story about knowledge arrived at via an objective scientific process, that process mediated by a community of people striving to divorce their work from any sort of social influence. If this story is to be believed, the edifice of science is a special place, a place in which the normal rules of subjectivity of knowledge do not exist and in which Truth can be discerned. This story of gradual accumulation of ever-greater understanding of the universe fits in nicely with a vision of overall societal progress, so much so that science and progress have almost become synonymous. But what are the assumptions which underlie this story?

In his critique of the master legitimatory narrative, J.A. Schuster (1995) gets to the heart of one of the foundations of this narrative—the “myth of scientific method.” As Schuster argues, and as has hopefully been illustrated by a retelling of the Darwin story, there are a number of problems with the presentation of scientific method as a purely objective means of truth discernment. The first of these problems lies with the supposed objective observation of fact. Neither Darwin, nor any non-omnipotent scientist, is capable of gleaning purified nuggets of information from the world around them. Instead, our observations and experiences must be interpreted and passed through a lens that includes all of our ideas about how the world works. Schuster (1995) refers to the “shaping of perceptions by prior knowledge, beliefs, values, and aims” as the theory-loading of perception. Theory-laden perception helps to explain why Darwin’s initial ideas make more sense when interpreted through his zeitgeist than our own, why some facets of his theory have had to be discarded, and why prevailing theories of his time had such a profound influence upon the formulation of his own ideas. These theories, whether or not he agreed with them in totality, comprised the imperfect lens through which Darwin made sense of his observations. Hence the faulty influences of Lamarck and Malthus upon Darwin’s theorizing are not some sort of exception, but the rule; the same can be said however for the positive influence of Lyell. Further, this theory-loading of perception is not an example of “bad science,” but is simply inherent in the way that humans exist in a world comprised of limitless, confounding stimuli; given the choice between perpetual confusion and a workable, if limited understanding of the world around us, our brains make the choice on our behalf.

Hence we observe the profoundly important role, indeed, perhaps even primacy, that “prior knowledge, beliefs, values, and aims” can play in shaping an individual’s interpretation of the facts (Schuster 1995). Commitment to a particular theoretical worldview—whether that commitment is based on intellectual, social, or spiritual underpinnings—influences what questions we ask, how we go about answering those questions, what evidence we are willing to accept, and how that evidence is construed. It is even possible that identical facts can be used to support opposing theories. Darwin’s disagreements with the idealists, for instance, demonstrates how one observation—unity of type—was used to support both evolution and the idea of archetypes. In this case, there was no immediately clear answer to this disagreement; the different theories were, in a sense, incomparable. Both interest groups continued amassing evidence to support their views, and the Darwinist victory was eventually obtained as a result of a number of factors, not all of them entirely scientific (Hull 1988). In hindsight, we know that Darwin’s ideas were more correct than the idealists, or at least that they are a better fit with our own modern ideas. But it is an interesting thought experiment to consider how future observations—the universality of the nucleotide-based language of the genome, for instance—might have been interpreted had the idealists overcome the Darwinists. It is not unreasonable to suggest that the biological sciences could be operating today under a highly modified version of idealism rather than modified Darwinism. Indeed, such questions begin to reveal how profoundly theory-laden our own perceptions are today, as biology students are indoctrinated with evolutionary theory and are instructed to interpret their observations through a natural selection lens.

The danger in these basic challenges to the purported objectivity of scientific method is not that they undermine science itself—quite the opposite. A realistic assessment of how the edifice of science works, where the weak points can be found in its structure, can only assist scientists in their goal of eliminating social biases from their efforts. The real danger is that questioning scientific method causes one to question further assumptions that flow from it. If we believe that science reveals truth, first and foremost, and that its findings are not obscured by subjective forces, then questioning science becomes tantamount to questioning truth (Schuster 1995). Hence the furthering of science becomes equated with progress, and unscientific becomes synonymous with dishonesty, or at least unreliability. This coupling of science and progress is what entitles Gould (1999) to insist that a blow against evolutionary theory is a blow against society itself. Yet just as the story of Darwinism reveals more than simply a contest between those who favored progress and those who opposed it, the long history of science reveals numerous instances in which science cannot be so neatly equated with progress. The dark history of the scientific community’s support for eugenics, stretching from Nazi Germany, through much of 20th century America, to modern-day China, reveals the dastardly effects of unchallenged scientific ideology coupled with social inequity (Ridley 1999). The development and use of nuclear weapons provides another example, in which the simple pursuit of knowledge, funded and directed by a militaristic state, can have horrendous ramifications. While it would be an unreasonable stretch to equate proponents of evolution with proponents of eugenics or nuclear weapons (at least in my mind), it is clearly not difficult to make a case for skepticism as regards the coupling of science and progress.

Given the limitations of scientific method and its proprietors, and given the justified skepticism with which we should always approach scientific findings, it seems reasonable to make a case for tentativeness, or humility, within the sciences. Yet arrogance abounds. Whether it is Gould’s (1999) curt dismissal of those who challenge evolutionary theory, or Matt Ridley’s (1999) neglect of any notion of free will that is not easily quantified, proponents of a scientific worldview repeatedly overstep their authority. In such an environment, Gould’s assertion that science is no threat to religion and philosophy rings false. In the increasingly technocratic society we inhabit, disciplines such as philosophy and religion have no choice but to grapple with the implications of science. Is there a corresponding willingness on the part of most science faculty and researchers to better understand how their own discipline fits within a complex matrix of sociological, economic, and political forces? When scientists do enter the public realm, is it in this spirit of exploration, or to heap scorn at their opponents and cast them as modern Luddites seeking to cast a dark shadow over human society?

Were I compelled to defend the teaching of evolutionary theory in our public schools, I would approach the challenge rather differently than did Gould. Rather than making arguments based upon the truth of evolution, my arguments would be based upon my understanding of how science, as a process, works (or strives to work). I would explain that science operates much like a courtroom, where some evidence—regardless of its basis in truth—simply cannot be allowed as admissible; to do so would undermine the functioning of the process as a whole. This argument was used by Darwin against the idealists--essentially that observation (of unity of type) mistaken for causation degrades the operation of science (Hull 1988). I would acknowledge that evolutionary theory is not necessarily superior to creationism, but that the two are actually incomparable on the basis of what evidence is admissible within their respective courtrooms; the science courtroom has an inherent bias against arguments that cannot be easily quantified and tested, for instance. I would also feel little obligation to so neatly link my own understanding of evolutionary theory to that of Charles Darwin, since I recognize the ongoing permutations to which the theory has been and likely will continue to be subjected. Deconstructing the theory into its constitutive elements and being willing to discuss each of them separately would likely diffuse my opponents and undo the false polarization of a strict evolutionist-creationist debate; it might also help all parties to get to the heart of their disagreements. I would acknowledge the positive aspects of dissonance between competing narratives by looking to historical examples in which science has played a positive role in undoing theocracy, and in which out-of-control scientism has been challenged by faith-based moralists. And finally, I would recognize that much of the activity of science—i.e., its information gathering and direct technological application—would be largely unaffected by how strongly certain theoretical positions are maintained. This last point can be evidenced easily enough via a survey of how many science workers and students actually understand the complexities of the theory of evolution; such a survey may well reveal that their commitments are based upon the sort of indefinite provisional assent called for by Gould rather than an actual basis in the facts.

At its base, the creationist-evolutionist argument seems less about the effects of the debate on science, or on societal progress, as it is about power—whose story or meme gets replicated to the next generation. Both sides may appeal to the Truth of their positions, and these appeals may indeed help to rally the troops, but in the end such language smacks of rhetoric. I, for one, have no more desire to live in a technocracy than I do a theocracy; as such, I have an interest in speaking out against what David Hull (1988) calls the “romantic hypocrisy” that lubricates our societal discourse. In the final analysis, I recognize, as did Darwin and his allies, that the victor in this debate will not necessarily be those with the closest approximation of truth, but those with the best public relations machine in place. Perhaps in that light, Gould’s propagandizing makes the most sense; whether or not his views are true is a question better left to hindsight.

1). Myth: A popular belief or story that has become associated with a person, institution, or occurrence, especially one considered to illustrate a cultural ideal; A fiction or half-truth, especially one that forms part of an ideology. Source: The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2000 by Houghton Mifflin Company.

2). Whether or not a “lie” must imply a conscious intent to propagate untruth is left for the reader to decide. For the purposes of this paper, I define a lie as simply propagation of untruth, regardless of the liar’s awareness that their words are untrue; hence referring to someone as a liar, as I do with Gould, may simply speak to ignorance rather than malevolent intent on their part.

3) These assertions, implicit in the mind of most scientists, form part of what J.A. Schuster refers to as the “master legitimatory narrative” of Western societies.

4) Convention: The primary tool governing the communication of meaning in film; repeated stylized interactions between the actors that viewers have come to expect from watching countless other films of the same genre. As defined by Margaret R. Miles in Seeing and Believing: Religion and Value in the Movies. Beacon Press: Boston, 1996.

5) As Pigliucci points out, the term “creationist” is a convention which is frequently used by supporters of evolution to neatly categorize all opponents or critics. For the purposes of this paper, I define as “creationists” those who seek to advance a worldview which adheres to fundamentalist Christian philosophy and those whose thinking is profoundly influenced by that philosophy.

Bowler, Peter J. 2003. Evolution: The History of an Idea. Berkeley, University of
California Press.
Butterfield, Herbert. 1965. The Whig Interpretation of History. London, W.W.
Norton & Co.
Darwin, Erasmus. 1794. Zoonomia: or the laws of organic life. London, J. Johnson.
Denton, Michael J., Peter K. Dearden, and Stephen J. Sowerby. (2003). "Physical
law not natural selection as the major determinant of biological complexity
in the subcellular realm: new support for the pre-Darwinian conception of
evolution by natural law." Biosystems, Vol 71, Issue 3, October 2003.
Gould, S. J. 1999. “Dorothy, It’s Really Oz.” Time Magazine, August 23, 1999.
Hull, David L. 1988. Science as a Process: An Evolutionary Account of the Social
and Conceptual Development of Science. Chicago, University of Chicago Press.
Jones, Steve. 2000. Darwin’s Ghost. New York, Ballantine Books.
Keller, L. and H.K. Reeve. 1999. Levels of Selection in Evolution. Princeton,
Princeton Univ. Press.
Pigliucci, Massimo. 2002. Denying Evolution: Creationism, Scientism, and the
Nature of Science. Sunderland, Sinauer Associates.
Ridley, Matt. 1999. Genome. New York, HarperCollings Publishers Inc.
Schuster, J.A. 1995. An Introduction to the History and Social Studies of
Science. University of Wollongong, Australia.
Volpe, E. Peter and Peter A. Rosenbaum. 2000. Understanding Evolution. 6th ed.
Boston, McGraw-Hill Company, Inc.

No comments: