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Breaking our link to the “March of Progress”

The views expressed are those of the author and are not necessarily those of Scientific American.


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It never fails. Whenever scientists announce the discovery of a hitherto unknown fossil species intermediate between two already known forms there is always one newspaper or magazine that calls it a "missing link". Score another point for evolutionary science—another gap in the fossil record has been filled in.

I hate the phrase "missing link". It immediately sends up a red flag in my mind, and is almost always a sure indicator that the person employing it has only a very superficial understanding of the way evolution works. To understand why this is, however, we have to inspect the intellectual baggage that the phrase carries with it.

Long before the explosion of evolutionary ideas during the mid-19th century, scholars of various stripes arranged all of nature according to an intricately graded scale called the Great Chain of Being. (Arthur Lovejoy’s book by the same name remains one of the most comprehensive studies of this concept through history.) Rooted in the ruminations of Plato and Aristotle, but most famously adopted by Medieval theologians and Renaissance thinkers, this concept ranked the natural world into a static hierarchy which elucidated the character of the Almighty. The chain was not a ramshackle assemblage of minerals, plants, and animals, but instead a carefully ordered sequence of increasing complexity and closeness to God in which our species occupied a crucial hinge point – animal in body but infused with a divinely-prescribed soul.

There could be no gap in this linear sequence. Given God’s wisdom and grace, every link in the chain had to be filled in. This caused some rather hairy dilemmas. Prior to the discovery of the great apes by Western naturalists during the 18th century, there was nothing between the vulgar monkeys and us. Strange "wild men" captured in western Africa and seen in the jungles of Indonesia eventually filled this gap—what we now call orangutans, gorillas, chimpanzees, and bonobos—and were comfortably slotted in between us and "lower" primates. They were exceptionally humanlike in body, but could not speak or reason, and hence were cast as near-humans which lacked souls.

By the dawn of the 19th century, however, the Great Chain of Being was no longer useful as an organizing concept. Naturalists were cataloguing such a wide diversity of species that they could not all be ranked one above the other. The hierarchy only worked if there were relatively few creatures which were disparate in character. The circulation of evolutionary hypotheses and speculation during the early 19th century also broke down the idea that nature was static, and of course we all know that in 1859 Charles Darwin took the controversial idea of evolution by natural selection and presented it as an idea which merited careful, thorough investigation. Darwin did not shoehorn life into constrained, straight-line hierarchies, but perceived innumerable, branching lineages which were constantly changing according to the exigencies of local ecology.

Fig. 1 – The single image in On the Origin of Species, depicting the branching nature of evolutionary change. From Darwin, 1859.

But the old imagery still held fast. By the late 19th century the order of the Great Chain had become impressed onto the geologic timescale and the appearance of life on Earth. (Just as fish were inferior to amphibians, for example, fish appeared before amphibians in Earth history.) Given the capricious nature of the fossil record, however, paleontologists did not have a complete record to investigate. There were significant geologic and evolutionary gaps in the history of life. Darwin knew this well and accounted for it in On the Origin of Species, but other naturalists took the lack of finely graded transitional series as a sign that evolution had occurred in rapid jumps or by some mechanism very different from natural selection.

It wasn’t all that long before potential transitional series began to be identified. During the 1870’s T. H. Huxley—the English anatomist who was evolution’s staunchest public advocate—presented plausible scenarios for the evolution of whales from land-dwelling carnivorous mammals, of horses from tiny, multi-toed ancestors, and of birds from dinosaurlike reptiles. Of these only the horse sequence was represented by relatively complete string of species which could be considered as ancestors and descendants, but Huxley underscored each case as a relatively straightforward, stepwise process of change along a linear evolutionary pathway.

This is the scientific context in which the phrase "missing link" became popular, especially in reference to human evolution. Darwin’s evolutionary theory predicted long strings of finely-graded species in the fossil record, and now that they knew what to look for paleontologists were beginning to find them. As was the case when the intellectual grip of the Great Chain remained firm, what existed in the shadowy place between monkey and human was of extreme interest. Were our ancestors really like the apes kept in the zoological gardens, or were they more of a "pre-sapiens" type—like us but rougher around the edges? The Neandertals, first discovered in Germany right around the time that evolutionary debate was ramping up in the 1860’s, were too close to us to fill that space. No one could agree whether they were a distinct species, a throwback, or pathological individuals of our own species. Instead the first fossil to be widely heralded as a missing link was "Java Man"—known to us today as Homo erectus—discovered by the Dutch physician Eugene Dubois in Indonesia. There was debate about this fossil just as there was about the Neandertals, but it was the first fossil with the right mix of "human" and "ape" characteristics to fit snugly in a straight-line progression of human evolution from primitive, brutish ancestors to modern humanity.

Stripped of its theological underpinnings, the image of minutely-graded, linear evolutionary transitions proliferated. There is perhaps no more direct way to illustrate macroevolutionary change than to lay out a series of transitional forms which document the change from the archaic into the modern. This kind of imagery is quick, easy, and powerful, but it also obscures the grander patterns of the fossil record which paleontologists have recognized for well over a century.

Fig. 2 – The traditional image of horse evolution from the archaic Eohippus [bottom] through the modern Equus [top]. From Matthew, 1926.

Let’s take the evolution of horses as an example. The evolution of the modern Equus from the diminutive Eohippus is one of the most iconic of all evolutionary transformations, and typically a series of multi-toed horses are slotted between the two following the pattern which Huxley and other naturalists laid out. But, as paleontologists have recognized since the beginning of the 20th century, there were too many fossil horses to fit into this geologic chain. Horse evolution was a branching process in which multiple species and genera lived alongside one another, some leaving descendants and others sinking into extinction. The technical literature on horses from the past century is full of branching evolutionary trees, yet the chosen depiction for books and museums—perhaps in response to the threat of creationism and Christian fundamentalism which reared its ugly head in 1920’s America—was of a linear series in which both the geologic and anatomical gaps had all been filled in. If a horse did not fit on the neat march towards modern Equus, it was simply left out as an aberrant side branch.

The dichotomy between what scientists know and what the public is presented with still hangs on now, even as research conducted within the past 30 years has shown horse evolution to be a tangled story which cannot be corralled into a straight-line narrative. Not only were there multiple radiations of horses over time, but there were even some reversals in which large lineages became dwarfed. There was no onward-and-upward march towards Equus. Instead, in what Stephen Jay Gould called "Life’s Little Joke," the only reason we can hold horses up as an evolutionary icon is that there is one genus left, making it easy to condense all those fossils into a linear pathway.

Fig. 3 – A modern (2005) vision of horse evolution. Any straight-line march of fossil horses would have to leave out numerous collateral relatives. From MacFadden, 2005.

Horses have not been the only groups of vertebrates to fall victim to this kind of imagery. Since it is the standard mode of evolutionary storytelling, the origins of the first tetrapods from fish, the earliest birds from dinosaurs, of whales, of elephants, and—of course—humans have all been cast this way. The cases of feathered dinosaurs and early humans, especially, underscore the struggle between what paleontologists have found and the traditional narrative of linear change.

An influx of new fossils and the development of new techniques have revolutionized our understanding of bird origins during the past decade. The origin of birds is much more complicated than the straightforward transformation of a single lineage of small, feathered, predatory dinosaurs into flying avians as has often been portrayed. Many traits once thought to be unique to birds and their direct ancestors—such as feathers and complicated sets of air sacs which leave telltale pockets on skeletons—have been found to be widespread among dinosaurs. Just last year, in fact, paleontologists found that Tyrannosaurus rex—a distant cousin of the dinosaurs which were ancestral to the first birds—suffered infestations of a microorganism which bored holes into the jawbones of their hosts and are still commonly seen in living hawks and pigeons. Rather than dinosaurs being birdlike, it is perhaps more proper to say that living birds are dinosaurlike, and we cannot hope to achieve a comprehensive understanding of avian evolution without more fully understanding dinosaurian evolution as well.

Fig. 4 – The lower jaws of a hawk [left] and a Tyrannosaurus [right] showing lesions created by the microorganism Trichomonas gallinae (or a similar species in the case of Tyrannosaurus). From Wolff et al., 2009.

Human evolution has also been traditionally depicted in an upward push towards modernity, as if we had been driving our own evolution all along. The most famous depiction of this—adapted from an illustration in the 1965 Time–Life book Early Man—is called the "March of Progress". It is exactly what it sounds like—a parade of human evolution from an archaic ape to a tool-wielding modern human.

Yet we know human evolution never took such a direct path. As with horses, during the past six million years there have been multiple species of human living on the planet at any one time. It is truly unusual that there is only one species today, and the rapid discovery of new species has shown the human family tree to be rather bushy. Even our own direct ancestry was marked by branching events. In 2007 a team of paleontologists lead by Fred Spoor announced that fossil evidence from Ileret, Kenya showed that Homo habilis and Homo erectus—long regarded as two successive stages in our own ancestry—had overlapped with each other for a few hundred thousand years.

News reports crowed this discovery rewrote our evolutionary history—a bit of boilerplate which is trotted out almost anytime anything new is discovered about human evolution—but it actually was perfectly consistent with what we know from other fossil transitions. As outlined by Gould and Niles Eldredge in their theory of punctuated equilibrium, descendant species can rapidly branch off from an ancestral stock which is going through a period of little change (stasis). The pattern this creates is of ancestral and descendant species overlapping in time. In this case, Homo erectus branched off from a population of Homo habilis and both coexisted for a time before the ancestral species became extinct, and depicting their relationship as simply a straight line blinds us to this branching trend. (Of course, the alternative scenario of both Homo species having branched off independently from an earlier common ancestor is also possible, but there is no hard evidence to support this hypothesis and it would still be best understood within a more tangled evolutionary scenario.)

Given all that we have learned about evolutionary patterns in the fossil record, why do we keep returning to the same outdated imagery?

At the beginning of the 20th century, American fundamentalism was gaining momentum and the public circus that was the Scopes trial turned the teaching of evolution into a controversial public issue. Now, at the beginning of the 21st century, anti-scientific opposition to evolution remains a prominent cultural force. Be it straight-up young-Earth creationism or its insidious sibling intelligent design, fundamentalism-fueled views of science and nature abound. Groups such as the National Center for Science Education are continually tracking the spread of anti-evolution agendas which would further erode the quality of scientific understanding. Perhaps this is why we keep returning to the March of Progress. When the fossils and stratigraphy are laid out so plainly, how can any reasonable person deny that evolution is a reality? Yet, by preferring this antiquated mode of imagery, we may have hamstrung ourselves. Given all that we have gleaned about evolution from the fossil record—especially the major pattern of contingent radiations cut back by extinction before bursting into numerous splendid forms all over again—why not bring this wonderful "tangled bank" imagery to the public?

Of course the problem is not just one of imagery or the way in which science education has suffered. Anti-science attitudes are influenced by religion, politics, and other sociocultural factors which make it impossible to offer up any single antidote. Nevertheless, we have to do more than simply say "We have the fossils; we win." If we become so focused on rhetoric and winning an argument that we strip evolutionary changes from their full context, then we are only setting ourselves up for failure as public presentations of evolution continue to drift from what we truly understand.

This is a boom time for paleontology. New species are being discovered and described at an astonishing rate and techniques from molecular biology, genetics, embryology, geochemistry, and other disciplines are allowing us insights into prehistoric life which have never been possible before. (See David Sepkoski and Michael Ruse’s recently-published The Paleobiological Revolution for an excellent overview of these changes to the discipline.) The age when museums would send out their best bone hunters for top museum-quality specimens alone is over. We are now in a time when paleobiology is more vibrant than it has ever been. This reinvigorated science is providing the detailed context by which to understand life as it is today, and it is essential in understanding what G. G. Simpson once called the "tempo and mode of evolution." We should take full advantage of this, and step one involves casting out types of imagery which constrain rather than enlighten. I, for one, would not miss the phrase "missing links" at all.

References:

Darwin, C. 1859. On the Origin of Species by Means of Natural Selection. London: John Murray.

Eldredge, N., and Gould, S.J. 1972. Punctuated equilibria: An alternative to phyletic gradualism. Models in Paleobiology. San Francisco: Freeman, Cooper and Company. pp 82–115

Gould, S. J. 1991. Bully for Brontosaurus. New York: W.W. Norton and Company. pp. 168–181

Howell, F. C. 1965. Early Man. New York: Time Life Books. pp. 41–45

Huxley, T. H. 1870. The anniversary address of the president. Quarterly Journal of the Geological Society, London, XXVI: xxix–lxiv

Lovejoy, A. 1964. The Great Chain of Being. Cambridge: Harvard University Press.

MacFadden, Bruce. 2005. Fossil horses—Evidence for evolution. Science 307: 1728–1730

Matthew, W. D. 1926. The Evolution of the Horse: A Record and Its Interpretation. The Quarterly Review of Biology, 1: 139–185.

Sepkoski, D., and Ruse, M. 2009. The Paleobiological Revolution. Chicago: University of Chicago Press.

Simpson, G. G. 1944. Tempo and Mode in Evolution. New York: Columbia University Press

Spoor, F.; Leakey, M. G.; Gathogo, P. N; Brown, F. H.; Anton, S. C.; McDougall, I.; Kiarie, C.; Manthi, F. K.; Leakey, L. N. 2007. Implications of new early Homo fossils from Ileret, east of Lake Turkana, Kenya. Nature 448: 688–691

Wolff, E.; Salisbury, S.; Horner, J.; Varricchio, D. 2009. Common avian infection plagued the tyrant dinosaurs. PLoS One 4: e7288 http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0007288

About the author: Brian Switek is a freelance science writer and a paleontology research associate at the New Jersey State Museum. He has written articles on paleontology for a variety of popular and academic publications—from the London Times to Evolution: Education and Outreach—and he presently blogs at WIRED Science’s Laelaps and Smithsonian magazine’s Dinosaur Tracking. His first book—Written in Stone: Evolution, the Fossil Record, and Our Place in Nature—has just been published by Bellevue Literary Press. To keep up with Brian’s latest work, follow him on Twitter @Laelaps or friend him on Facebook.

The views expressed are those of the author and are not necessarily those of Scientific American.

 






Comments 32 Comments

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  1. 1. tharriss 10:20 am 12/3/2010

    Nice work, thank you!

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  2. 2. Tucker M 10:54 am 12/3/2010

    Lovely article and argument, thank you.

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  3. 3. jtdwyer 12:29 pm 12/3/2010

    A very nice social analysis. It must be understood that those who object on religious grounds are at best searching for some method of incorporating the scientific data within religious preconceptions. There is no convincing…

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  4. 4. frankblank 3:02 pm 12/3/2010

    Good article! And highly amusing. Many years ago in school I did an analysis of how Hamlet descended the great chain of being to arrive at, well, a terminal mess.

    Ever since, I’ve been sad to see how rarely the chain of being is discussed, even though it obviously informs many people’s notion of reality.

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  5. 5. Major_Ray 3:05 pm 12/4/2010

    Very good for paleontology. However, evolutionary theory and Darwinism will soon be replaced by Creationism and Intel Design. This rising movement will not stop regardless of what scientists say.

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  6. 6. mayankmpat 3:53 pm 12/4/2010

    Given the increased momentum and popularity that faith-based movements have gained in deciphering our state of being – what does that say about (the real) evolution of human intelligence (read ability to philosophize)? That it has plateaued, or even started regressing? Or is that this dichotomy actually represents the budding off of two separate branches in our evolution? That would be the optimistic outcome (as long as "they" are sent away to inhabit Mars).
    It could be that it doesn’t really matter who gets the last word in, because unless we evolve enough to get along with each other we are all doomed (surely, the increase in violent means of expression of fundamentalism is not lost on anyone)!
    I hope the Mars habitat idea works out.

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  7. 7. jtdwyer 4:55 pm 12/4/2010

    How sad.

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  8. 8. Circuitman1996 6:00 pm 12/4/2010

    This article is a laughing stock to the scientific community. This author has such a bigoted attitude toward Christianity and the belief in creationism. I am a Christian and a biologist. The author of this article in multiple places indicates that a person that opposes evolution is anti science. I do not believe that cows evolved into whales but that does not mean I oppose science. A person that is a young earth creationist does not mean they oppose science. It does mean that they have interpreted the evidence differently than the author did. I am disappointed in the editors of this magazine for allowing such a bigoted and unscientific viewpoint to be published.

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  9. 9. bewertow 7:03 pm 12/4/2010

    Circuitman, YOU are the laughing stock of the scientific community. I doubt that you have a degree even remotely connected to biology if you are stupid enough to believe in young Earth creationism. The evidence against creationism is so massive that you cannot possibly pretend to be intelligent while still holding onto that outdated dogma.

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  10. 10. denswei 8:46 pm 12/4/2010

    I’ve never seen a creationist argument that held water. If one bothers to check facts, one inevitably finds misunderstood theories, misrepresented data, misused statistics, and misquoted authorities. As a great chain of logic, it is nothing but missing links.

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  11. 11. denswei 8:53 pm 12/4/2010

    Intelligent Design as originally argued by Behe? If you bothered to read Darwin’s Black Box, you would know that (1) evolution is a major tenant of ID, since God (or whatever) only intervened to engineer some very specific cellular structures that could not have evolved, (2) as is an ancient earth.
    Any concept of Intelligent Design that excludes those premises is just relabeled, old-fashioned, and thoroughly debunked creationism.

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  12. 12. denswei 8:57 pm 12/4/2010

    Perhaps we need to use the phrase ‘missing branches’ instead of ‘missing links’.

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  13. 13. Befell 11:39 pm 12/4/2010

    I can only hope that religiously AEVASIVE human animals will speciate away from the kind of non-religiously AEVASIVE human animals that I (and others like me) belong to! :-/

    "Homo Sapiens Sapiens" is a highly inappropriate and undeserved name/description that covers all kinds of (including both religiously naive and intelligently irreligious) people.

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  14. 14. zstansfi 1:22 am 12/5/2010

    Your statements clearly reflect a mis-understanding of the scientific method. The purpose of science is to delineate objective, empirical and falsifiable evidence in support of hypotheses. While the very basis of science requires that we cannot "prove" absolutist claims to be true, it does not mean that all viewpoints are equally valid. There is a vast amount of evidence which strongly supports the contention that Evolutionary Theory accurately describes how organisms have evolved over many millions of years. This is a factual statement. Just because future evidence might be produced to refute part or even all of Evolutionary Theory does not make this statement any less true. Nor does one’s "belief" play any part in whether this statement is factually correct. Scientific evidence is not subject to "belief", it is subject to objective analysis and falsification through the careful, systematic accumulation of evidence.

    I should also point out, you are welcome to your beliefs–this is your right as a member of a free society–whether they be beliefs based in evidence or otherwise. You are also perfectly welcome to disagree with, or provide evidence which disputes current scientific theories and to postulate your own hypotheses. What is more: no rational person will ever ask you to hold ONLY scientifically verifiable beliefs. However, if you believe that Creationism is a scientifically valid concept, then clearly you are deluding yourself as to the function of the scientific method.

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  15. 15. tuibguy 8:18 am 12/5/2010

    If you oppose evolution without presenting the science behind your opposition, it is you who are a laughingstock.

    The word bigotry is tossed around quite freely, but in the context of illustrating that people who believe in creationism have been proven time and again that they have been proven wrong, it has no place and is used a blunt instrument to try to deflect from the true issue at hand.

    This is a strongly illustrative article that dispels the notion, common both to those who accept evolution but don’t understand it well and those who reject evolution religious grounds, that evolution follows a linear progression from simple to complex life is a mistake.

    You would do well, Circuitman1996, to read Brian’s book. It is well-written and clear on how the rocks themselves show the process of evolution. You are behooved, if you are seriously into biology, to at least have a solid understanding of that which you are criticizing.

    Unless, of course, you merely wish to stand in the field and cry "Help, help, I am being oppressed."

    It is also ludicrous for Major_Ray to claim that anything will be gained by replacing science with the ignorance that permeated our knowledge in the 18th century.

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  16. 16. AnimalCO 5:28 pm 12/5/2010

    No, you are not a biologist, nor are you a scientist of any stripe. I have long seen that creationists will lie as reflexively as they draw breath. You are one such.

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  17. 17. Centaurus-A 3:42 am 12/6/2010

    Again, Brian’s article is a flashpoint, a microcosm of the utter contempt that he has for the Christian position. It takes this to a new level. A level where everything wrong with the standard model of evolution is blamed on theology. I say this to Brian: this is a poor peice of writing. You appear to be a high school kid and you need to grow up son.

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  18. 18. Centaurus-A 3:55 am 12/6/2010

    "Be it straight-up young-Earth creationism or its insidious sibling intelligent design, fundamentalism-fueled views of science and nature abound. Groups such as the National Center for Science Education are continually tracking the spread of anti-evolution agendas which would further erode the quality of scientific understanding. Perhaps this is why we keep returning to the March of Progress."

    Let me be specific. This paragraph above is incorrect. By saying the last statement "perhaps…" What a total collapse of logic this is. This is Brian’s own ruminations not scientific at all but a "perhaps" a supposition an opinion.

    No Brian, you are a totally clueless writer masquerading behind your very slight scientific credentials. No, "the march of progress" evolutionary tree was created by evolutionary scientists who believed in God not the other way around. It isn’t the influence of religious pressure that has influenced scientists. Scientists could care less about religious pressure. It is rather from those scientists who believed in God who kept creating these kind of diagrams. You know nothing about the history of science. Many of the founders of modern paleontology that you are now a beneficiary of were believers in God. Look at Walcott for example–a devout Christian. Read "A Wonderful Life" by Gould and you will know the truth and the truth will set you free.

    So quit espousing your ideological bias and propaganda as atheist, and learn to appreciate your founding fathers of many of the sciences.

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  19. 19. Centaurus-A 4:18 am 12/6/2010

    And for anyone who would espouse that evolution and a correct understanding of biology precludes the concept of God please prove this. There is no proof that God does not exist using the scientific method neither is there proof He does exist using this method. It is not in the realm of science (or the scientific method) to answer this question. Other kinds of knowledge are involved in determining this question. If by science education we mean to prohibit or deny religious faith how are we to reach out to the public. No wonder why there is such anger and misunderstanding among the public about science. Most scientists I know are not this way. They are not atheists but are typically agnostic. Many believe in God as well. And those people who are on here constantly criticizing others for holding to Christian beliefs are themselves rejecting the faith for a different reason not connected to science. They are ideological atheists, many of whom are not even scientists.

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  20. 20. manyfaucets 12:11 pm 12/6/2010

    I would also add "self-replicating molecules" to the list of red-flag phrases. This flawed notion has been oft quoted as the holy grail of molecular evolution. In fact, it very likely has nothing whatsoever to do with evolution. That doesn’t mean that it isn’t an interesting possibility in its own right but when it is associated with evolution as an insight into early evolution, it confuses and misdirects.

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  21. 21. sckavassalis 5:20 pm 12/6/2010

    This was a wonderful article; I’m sad to see so much creationist hate towards good writing and well articulated science. However, just because some of the louder voices on the internet happen to be a little clueless, it doesn’t need to take anything away from the fact that now is really a great time for paleontology, and science in general.

    "We are now in a time when paleobiology is more vibrant than it has ever been." – Yes! And this is exciting, and beautiful, and what will, slowly but surely, lead to the global acceptance of the theories that come from it (ie. evolution).

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  22. 22. b_calder 5:47 pm 12/6/2010

    Brian has done a good job writing about the situation as it stands today. Unfortunately, his detractors demonstrate that many of the characteristics that cause them to hew to wrong headed ideas are indeed those that cause them to persist in those views. They are sadly behind the state of actual science as usual. A person that is a young earth creationist may not *think* he opposes science, but then he doesn’t really understand what it is.

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  23. 23. alunsalt 5:55 pm 12/6/2010

    I thought it was a very good article. It reminds me a lot of what Daniel Lord Smail has been saying about the development of History (in On Deep History and the Brain). After abandoning the Bible as historical narrative, History was seen as pinned to texts. So instead what you have is an origin of civilisation story based on the rise of agriculture in Mesopotamia, with historical humanity spreading from this original point.

    This mode of thought persists in current History courses in American universities. Prehistoric humans, being quite literally pre-historic don’t appear in the historical record so you get the start of civilisation as an event with a linear narrative to Western Civilisation.

    Yet in the historical record this kind of presentation also puts modern civilisation as the end result, possibly even the only natural and inevitable result of human development. Conveniently that makes us superior to what has gone before and therefore justified in dealing with what we think of a primitive societies.

    I’m wondering then if there’s a strong secular element of now being the inevitable result of evolution and therefore all environmental actions in the current era being justified. Just as linear histories lead to us as the dominant feature so to linear evolutionary tales make the purpose of nature to create us as the end point. A more sophisticated tale of evolution as a many branched process threatens to remove humans as The Big Important Thing.

    It doesn’t discount the strong social pressures from creationism, but it might show how secular and religious linear narratives co-evolved to embed linear development as the default explanation and the debate being reduced to the matter of the mechanics of how it works.

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  24. 24. Dana Hunter 6:18 pm 12/6/2010

    Fantastic as ever, Brian! I hope educators of all stripes pay attention to this post, because the Great Chain needs breaking.

    Ultimately, that linear way of explaining evolution set me back several years. Yeah, it may be simple, but it’s too simple. It doesn’t leave room for all the side trips, dead ends, and scenic routes, and it doesn’t give a person room to think outside of a destination. That confused the hell out of me, because there are plenty of things that didn’t reach the supposed destination, but were there for a good part of the journey. It’s like supposing several cars worth of people can only travel between Phoenix and Flagstaff: you can’t explain then why some of them buggered off sideways to Prescott instead.

    Once I saw the tree, it started to make sense. Not every branch goes "up." The top of the tree isn’t the only place to be. It’s still a simple model, but it’s one that leaves plenty of room for all the bits that don’t fit when you chain yourself to the Great Chain.

    That’s true in a lot of things about life. It’s time to let go of the black/white either/or thinking and embrace the world as it is: fuzzy, chaotic, contingent, and far more interesting than mere lines from A to B.

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  25. 25. Centaurus-A 7:17 pm 12/6/2010

    As usual you miscontrue my point because you would rather detract than face my argumant head on. I was just saying that Brian does not know his history. Again let me repeat, I am not a young earth creationist neither was Charles Walcott the famous paleontologist who discovered the Burgess fossils. I was pointing out that much of this linear thinking was posited by early paleontologists who also happened to be devout Presbyterians and believers. Again, Brian shows a lack of knowledge of this connection. I’m not debating the merits or the demerits of a linear theory just pointing out that his attribution is incorrect. This linear progression of evolution cannot be denied even by its detractors. And I’m not arguing theology here. When we look at a the history of earth the fossil recored DOES show the gradual evolution from simple organisms (bacteria) to more complex organisms (multi-cellular) for the most part, even when considering periodic extinction events.

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  26. 26. drskyskull 11:21 pm 12/6/2010

    Centaurus-A wrote:

    <blockquote>No, "the march of progress" evolutionary tree was created by evolutionary scientists who believed in God not the other way around. </blockquote>

    Sir, you’re embarrassing yourself. The particular paragraph you quote doesn’t say anything about who initiated the idea of the "march of progress", it discusses what misguided efforts in modern times have helped perpetuate the idea. Before you criticize the writing of others, you should perhaps work on some reading comprehension. I certainly won’t bother reading any of your clearly ideologically-based rants.

    ************

    That unpleasantness aside, I’d be interested in knowing: who was the first person to draw the "march of progress", and what was their background and what were their direct influences? Does anyone know?

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  27. 27. Centaurus-A 12:09 pm 12/7/2010

    Drskyskull,

    You say you will not read my posts, but obviously you are reading my posts LOL. It is Brian who is on a ideological rant and people who defend him like yourself. Brian is trying to make the connection between the bad influence of theological thinking on the Great Chain of Being and on the idea of progress in evolution. This is not historical. This is inaccurate. What is not clear when I say this? Read Gould in A Wonderful Life and see what he has to say about Walcott. I am just merely pointing out that one of the greatest paleontologists of the 20th century was a believer in God. Gould does not demonize believers at all nor does he attribute bad influences on evolution from religion. He simply states the fact that Walcott’s linear progression that he saw in evolution was influenced by his religion. It is too much for you to face because your objection to God is not reasonable but emotionally based. That’s my point.

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  28. 28. bucketofsquid 5:25 pm 12/7/2010

    I volunteer to go to Mars!!!

    Link to this
  29. 29. bucketofsquid 5:47 pm 12/7/2010

    The idea that humans are the pinacle of evolution is ludicrous <–(I have no idea how to spell that word). A simple fungus or bacteria can end our species as a viable life form.

    The simple fact is that science and religion are both evolving and adapting to the environment they find themselves in. A modern Christian such as myself bears no resemblance to an early Christian at all. I have found no prohibition against slavery, poligamy or even genocide in the New Testament and the Old Testament openly encourages all three. Indeed, early Christianity glorified being a slave because "the meek shall inherit the Earth". Even so, I hate all three concepts and view them as inherently evil.

    Early science in the west was conducted primarily by Catholic and Orthodox clergy or people sponsored by them. In the East and Mid-East, the science was conducted primarily by secular people funded by political entities.

    There is no conflict between religion and science. There is only conflict between theologies. Science doesn’t care.

    Link to this
  30. 30. Centaurus-A 4:15 am 12/8/2010

    bucketsofsquid, thankyou. That is what I said earlier that science does not care (my comment 19 above), nor can it be used to provide evidence to support or contradict the existence of God.

    What I was objecting to was the general tone of falsely attacking religious thought as holding science back by influencing the staying power of the idea of linear progress in evolution. I was just pointing out that Brian was wrong here. I’ll go further. It is actually the opposite.

    None other than Charles Darwin first proposed that the tree was a true simile of evolution (see chapter 4 on Natural Selection in the Origins). So Brian why not attack Charles Darwin? The theory of evolution itself has at its heart the unstated notion of improvement of species through "survival of the fittest" that Herbert Spencer took to extremes in the 19th century, even to the point of grading different races.

    I don’t deny religious influence and thought on the diagram but the origin of this is with the founder Charles Darwin. Not the Great Chain of Being.

    Link to this
  31. 31. jtdwyer 10:57 am 12/8/2010

    Isn’t this article objecting to the linear chain as the simile of evolution, not the tree?

    The difference, of course, is that a chain linearly progresses to its singular end point, whereas the branches of a tree have a common origin (the trunk) but innumerable potential ‘end points’.

    How would the existing human species respond if the growing incidence of autistic characteristics in the populace eventually produced a new human species of demonstrably superior intellectual abilities?

    Link to this
  32. 32. Bbear41 8:44 pm 12/15/2010

    I presume that you mean that, (at least in the USA) a right-wing theocratic administration will ban the teaching of evolution. I think it probable. Stalin banned the teaching of Darwinian evolution.

    Link to this

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