t f p g+ YouTube icon

Concerns About the Implications of BioLogos’ Science, Pt 5

Bookmark and Share

February 18, 2011 Tags: Science & Worldviews

Today's entry was written by Ard Louis. Please note the views expressed here are those of the author, not necessarily of The BioLogos Foundation. You can read more about what we believe here.

Concerns About the Implications of BioLogos’ Science, Pt 5

This is part five in a series taken from Louis' paper (downloadable here), which addresses common Christian misconceptions about the nature of science and its relationship to God's involvement in our world. Links to the first four parts are located on the side bar to the right.

In the last post, we considered several scientific metaphors for the evolutionary process. Today we examine a few more to illustrate that no metaphor tells the whole story about how evolution works. More importantly, none of them reveals where we come from or how we should live.

Shaven Baby, Tinman, Pax-6 and Sonic-hedgehog.

Genes that behave like switches have important consequences for development (how an organism changes from a fertilized cell into an adult). They are often given whimsical names like shaven baby (which makes the embryo hair fall off) or tinman (which governs development of the heart; the name comes from The Wonderful Wizard of Oz) or sonic hedgehog (a mutation in this genes gives the embryo little spikes). The same gene often turns out to be used throughout the animal kingdom: you can take the pax-6 gene that controls eye development from a human and put it into the part of a fly that controls wings formation and the fly will make a (malformed) eye on its wing. The same gene that controls the formation of human arms also controls the formation of wings on birds, fins on fish, and legs on centipedes! Modifying the way these genes are “wired together” can lead to massive changes in an organism. The burgeoning new field of evo-devo (evolutionary developmental biology) studies how evolution exploits these “toolbox genes” to help generate the endless forms most beautiful we see around us. Much remains to be understood, but adjectives like remarkable, elegant, and awe-inspiring are apt.

Clay or Lego Blocks?

In a fascinating book proposing a “theory of facilitated variation”1, biologists Marc Kirschner and John Gehrard point out that while the Modern Synthesis implicitly used the metaphor of clay -- evolution could produce variation in almost any direction, but in very tiny steps -- modern biology would be better served by the metaphor of Lego blocks: reusable connectable units are more constrained in what they can do, but you can generate useful new variation in much larger steps.

Selfish Genes, or Control on Many Levels?

The field of systems biology is challenging the reductionist bottom-up primacy that has dominated biological explanation over the last few decades. In a beautiful book, The Music of Life: Biology beyond the Genome (OUP 2006), Denis Noble, a remarkable polymath and one of the fathers of systems biology, takes the gene-centric view of his Oxford colleague Richard Dawkins to task. He asserts that we must look beyond the “selfish gene”. A better metaphor for understanding life is music, “a symphonic interplay between genes, cells, organs, body, and environment”. Earlier on in the book he mischievously inverts a famous passage from Dawkins’ The Selfish Gene (OUP 2006).

Dawkins himself admits that there is no experiment that he knows of that could distinguish these two viewpoints2. Nevertheless, this example does illustrate the power of metaphors: the concept of a “selfish gene” now permeates much popular thinking about evolutionary biology. There is a technical sense in which it is useful (e.g. in arguments about levels of selection3), but as a morally-freighted metaphor it is seriously misleading.

Evolution as a Tinkerer, or as an Engineer?

In a famous 1977 article entitled “Evolution as a Tinkerer”4, the French Nobel prize winner Francois Jacob introduced a powerful metaphor for the way that evolution can, for example, co-opt existing processes towards new ends. Unfortunately this metaphor also carries overtones such as ad-hoc and sub-standard. These connotations are then reflected in public debates about evolution. Whether tinkering is the best vantage point from which to view evolution is also not at all clear. In a provocative paper entitled “Biological Networks: The Tinkerer as an Engineer”5, the systems biologist Uri Alon showed how the biochemical networks that control cells display good engineering principles such as modularity, robustness, and the re-use of components. It should be kept in mind that the question of optimality is highly contested in evolutionary biology. To properly assess such questions one often needs consider counterfactuals, something that is much harder to do in biology than it is in say physics. Nevertheless, it seems to me that Jacob’s “tinkerer” metaphor is not nearly as widely applicable as some biologists claim.

Contingency or Inevitable Outcomes?

Wind back the tape of life to the early days of the Burgess Shale; let it play again from an identical starting point, and the chance becomes vanishingly small that anything like human intelligence would grace the replay.” In evolution, there is no direction, no progression. Humanity is dethroned from its exalted view of its own importance.

- Stephen J. Gould, Wonderful Life (W.W. Norton 1989)

When you examine the tapestry of evolution you see the same patterns emerging over and over again. Gould's idea of rerunning the tape of life is not hypothetical; it's happening all around us. And the result is well known to biologists — evolutionary convergence. When convergence is the rule, you can rerun the tape of life as often as you like and the outcome will be much the same. Convergence means that life is not only predictable at a basic level; it also has a direction. ….. the constraints of evolution and the ubiquity of convergence make the emergence of something like ourselves a near-inevitability.

- Simon Conway Morris, Life's Solution: Inevitable Humans in a Lonely Universe (CUP, 2003)

These two quotes could not be more different. Regardless of the metaphysical implications, it is a very fascinating scientific question to ask which man is right. Gould’s view is widely shared among biologists and frequently repeated in public debate. However, Conway Morris, one of the heroes of Wonderful Life, lists an astonishing catalogue of examples of convergence -- from antifreeze proteins to echolocation to social organization -- where the same features emerge independently in evolution.

My favorite quote on this topic is by Natalie Angier in “When Nature Discovers The Same Design Over and Over”, NY Times, Dec 15 1998:

Nature is like Henny Youngman: She writes great jokes, and then flogs them again and again. Take the spiny anteater of Australia, the pangolin of Africa, and the giant anteater of Latin America (please!). Each of these mammals has a long, sticky, worm-like tongue, no teeth to speak of and scimitar claws. Each has bulging salivary glands, a stomach as rugged as a cement mixer and an absurd, extenuated, hairless snout that looks like a cross between a hot dog and a swizzle stick […] Despite their many resemblances, the three creatures are unrelated to one another; the spiny anteater, in fact, lays eggs and is a close cousin of the duck-billed platypus. What has yoked them into morphological similitude is a powerful and boundlessly enticing process called evolutionary convergence. By the tenet of convergence, there really is a best approach and an ideal set of tools for grappling with life's most demanding jobs. The spiny anteater, pangolin and giant anteater all subsist on a diet of ants and termites, and myrmecophagy, it turns out, is a taxing, specialized trade. As a result, the predecessors of today's various ant hunters gradually, and quite independently, converged on the body plan most suited to exploit a food resource that violently resists exploitation.

This series is not the right forum to discuss the scientific implications of all this convergence. What is clear, I hope, is that evolution appears to be much more constrained than earlier generations of scientists may have thought.

So What Shall We Make of All These Metaphors?

One could describe evolution as a blind, purposeless, and directionless process that tinkers by modifying the genetic blueprints that determine our infinitely malleable biological outcomes. By a combination of random chance and survival of the fittest it stumbles upon contingent organisms best described as secondary phenomena cobbled together by selfish genes.

Or one could instead describe evolution as “a symphonic interplay between genes, cells, organs, body, and environment” that wires a toolkit of Lego-like components into interacting networks in order to explore a highly structured search space. The (inevitable?) outcome of this stochastic process is the emergent self-assembly of the “endless forms most beautiful” that include you and I.

The fact that there are so many different metaphors reflects the many facets of evolutionary processes. Christians may find some of these metaphors more palatable than others.6 But it must be kept in mind that all these metaphors, even those with which Christians would be more comfortable, are limited in their ability to fully capture the detailed scientific mechanisms at work. Nevertheless, familiarity with a broader spectrum of metaphors can help a Christian recognize the rhetorical subterfuge of those who pick specific metaphors over others in order to advance ideological agendas.6The most important point of this section is, however, that all these metaphors are severely restricted in what they can tell us about where we come from and how we should then live.

Notes

1. Marc Kirschner and John Gehrhard, The Plausibility of Life, Yale University Press, New Haven (2005)

2. For a more extensive discussion see D. Noble, Neo-Darwinism and Selfish Genes: Are they of use in physiology?, The Journal of Psychology, doi:10.1113/jphysiol.2010.20138 (2010)

3. S. Okasha, Evolution and the levels of Selection. OUP, Oxford (2006)

4. F. Jacob, Science, 196, 1161 (1977)

5. U. Alon, Science, 301, 1866 (2003)

6. D.R. Alexander and R. L. Numbers, eds., Biology and Ideology from Descartes to Dawkins, University of Chicago Press (2010)


Ard Louis is a Reader in Theoretical Physics and a Royal Society University Research Fellow at the University of Oxford, where he leads a research group studying problems on the border between chemistry, physics and biology. He is also the International Secretary for Christians in Science, an associate of the Faraday Institute for Science and Religion and served on the board of advisors for the John Templeton Foundation.

< Previous post in series Next post in series >


View the archived discussion of this post

This article is now closed for new comments. The archived comments are shown below.

Loading...
Page 1 of 1   1
Steve Ruble - #51530

February 18th 2011

I like the pair of alternate descriptions of evolution in the last section. I comfortably read them as describing identical things, with one exception: in the second paragraph, the “symphonic interplay” is described as doing its thing “in order to explore a highly structured search space.” While I can understand that phrase in a non-teleological way, I think that a natural reading of the sentence gives the impression that the process of evolution is trying or intending to explore the phenotype space.  That implication has no parallel in the first description - which explicitly denies teleology - and so I think that the examples ultimately do not provide interchangeable metaphors for the same underlying phenomena. 

I think this is an important difference. The implication of teleology can be helpful in a metaphor (e.g. the selfish gene) but, as the author himself points out, such anthropomorphizing of natural processes can be misleading.  The imputation of intention to natural selection itself (or a power behind it) is something which needs to be done through serious argument, not slipped in through (in the words of the author) rhetorical subterfuge, or (to be fair) careless phrasing of an example.


Jon Garvey - #51542

February 18th 2011

@Steve Ruble - #51530

A very fair comment, Steve. A strictly descriptive (and therefore scientific) formulation of evolution is philosophically and theologically agnostic, leaving room for the discussion of the presence or absence of purpose to other fields where it is legitimate.

But isn’t it the case that the discussion within society at large has been dominated since q976 by the highly loaded concept of the selfish gene> Noble’s admittedly faulty, and probably tongue-in-cheek, description could be seen as a welcome balance to this.


sy - #51661

February 19th 2011

Convergence is crititcal in evolution, but there is more evidence that suggests a direction to evolution that counters Gould’s argument. Fisher’s law of natural selection (which everyone, including Dawkins, seems to have forgotten) predicts that variation will always increase as a result of selection. This could be taken to imply that there is a tendency toward increased complexity, since increasing complexity allows for greater variation. Gould tends to deny that increased complexity is an actual direction of evolution, by showing that “simple” organisms, such as bacteria are the dominant life forms on Earth. I think that is incorrect (both that bacteria are dominant, and that they are simple), but that’s a whole nother topic.

If there is a trend toward complexity, (as the record shows), and if this is built in to the very fabric of evolution (according to Fisher) then the inevitability of intelligence may be assumed. Note that so far, this is not actually a teleological argument, although it has the appearance of teleology.


Jon Garvey - #51677

February 19th 2011

@sy - #51661

“If there is a trend toward complexity, and if this is built in to the very fabric of evolution then the inevitability of intelligence may be assumed.”

Does this really follow? Motor cars have shown a constant tendency to more complexity, but I’ve yet to meet one in a library.


sy - #51683

February 19th 2011

Well, Jon, Watson the computer just blew away two guys on Jeopardy so….

All kidding aside, there are intelligent machines, but I used the word intelligence on purpose. Dogs and monkeys are more intelligent than worms and goldfish, so there is an increase in intelligence as the brain gets more and more complex. But, to decide to go into a library and read something, (or to comment on a blog) you need more than intelligence, (which might not even be a necessary condition, in some cases). You do need free will, consciousness and human nature. No other animal, and to my belief, no machine, (no matter how intelligent) will ever have that. So we will not a need a sign in libraries that says “This section for humans only”.


Roger A. Sawtelle - #51705

February 19th 2011

“One could describe evolution as a blind, purposeless, and directionless process that tinkers by modifying the genetic blueprints that determine our infinitely malleable biological outcomes. By a combination of random chance and survival of the fittest it stumbles upon contingent organisms best described as secondary phenomena cobbled together by selfish genes.”

One could describe evolution in that way but one would be wrong.  It has been well demonstrated that our universe has been so constructed as to be able to produce life & evolution is the system that has produced life in all its diversity.  Even if one must not scientifically link the result with purpose, how can one say that the result has no purpose?

The article noted that evolution has produced similar unusual animals who are not genetically related to each other.  However if you look at the ecological niche that each of these anteaters occupy, you will find much similarity.  Life forms in similar ecological niches often use similar responses to similar challenges.  Many marsupials in Australia use the same ways to adapt to niches as mammals.


Roger A. Sawtelle - #51713

February 19th 2011

Part 2

Evolution is not blind, because it moves in step with the environment.  It also conforms to the rules of symmetry.

In the same way it is not without direction because it always moves forward and toward more DIVERSITY and more complexity.  Also more interdependency.

The term survival of the fittest has become a meaningless tautology.

The process is not random in a strict sense.  Genes are not free to connect in any and every fashion.  The process should be called indeterminant. 

Genes are not selfish in the way Darwin and Dawkins have portrayed them.  Genes constructed to take advantage of the nonzero nature of life where mutualism or cooperation makes best use of all the resources of an environment.  Darwinism portrays life as a zero sum situation where conflict fo resources is the way to survival.


Alan Fox - #51948

February 20th 2011

Genes are not selfish in the way Darwin and Dawkins have portrayed them

I am pretty sure Darwin did not portray genes at all. He did postulate something he called gemmules but I don’t think he ever used the description “selfish” in this context.

WRT to Dawkins, have you read “The Selfish Gene”? He explains at length that he is concerned with effects of behaviour, not motives.


Mike Gene - #51951

February 20th 2011

One could describe evolution as a blind, purposeless, and directionless process….Or one could instead describe evolution as “a symphonic interplay between genes, cells, organs, body, and environment”

Exactly.  Duck? Rabbit?  Who can tell?

What you are describing are perceptions of evolution, as metaphors as simply ways to communicate one brain’s perception to other brains.  This is so widespread and common because none of us can objectively see evolution with our eyes; we see it with our minds.

“Perception is not just a product of the stimulus, but also of mental activity – that we see with the mind as well as the eye.” - John F. Kihlstrom


Alan Fox - #52046

February 21st 2011

#51951

If we have phenomenon X and two explanations A and B, falsification of A does not affect the candidacy of explanation B. Moreover, the fact there may be another explanation, C, which has not been thought of and may ultimately prove correct. So Jastrow’s rabbit or duck may be an informative illustration of visual perception, it only suggests false dichotomies in a general sense..


Roger A. Sawtelle - #52123

February 21st 2011

“But it must be kept in mind that all these metaphors, even those with which Christians would be more comfortable, are limited in their ability to fully capture the detailed scientific mechanisms at work.”

The problem is that there are no detailed scientific mechanism to for Darwinian natural selection.

“Dawkins himself admits that there is no experiment that he knows of that could distinguish these two viewpoints.” 

If there were detailed mechanisms they could be tested.  Thank you for the reference to the abstract of an article that states that the “selfish gene” does not work for physiology, so it conflicts with other science as well as ecology.

Louis presents two conflicting models for the way evolution works, one is Darwinian based on Malthusian conflict.  The other is holistic more like the ecological model of Lovelace.  Kuhn, who wrote the book on scientific models and whom Dawkins has ridiculed, I think would say one model will win out, survival of the fitter if you will.  I agree and for me the available evidence clearly points to the ecological model as the one of the future.


Mike Gene - #52171

February 22nd 2011

Alan,

It’s not just visual perception, but all perception.  And it has nothing to do with “false dichotomies.”  It’s about ambiguity and how it tips the perceptual balance to the top-down processing that stems from the mind. 

In this situation, Ard Louis describes two general perceptions on evolution.  So the question needs to be asked – why are there two general perceptions? Why don’t all scientists, everywhere, share the same perception?  In other words, there is no “one true scientific” perception.  Why is that?  My answer is that we’re all dealing with an ambiguous reality, one that is more “up for grabs” than most people think. In steps Jastrow’s bunny (or is it a duck?).  If there is a better explanation, I’m all ears.

You are correct when you note, “If we have phenomenon X and two explanations A and B, falsification of A does not affect the candidacy of explanation B.”  That is why you won’t find me arguing that the Rabbit exists by trying to disprove the Duck.  On the contrary, my advice and method has always been about chasing dat rabbit and shunning attempts to hunt da duck. 

The non-teleologists don’t like the rabbit chasing.

The IDers insist on a good duck hunt.


Alan fox - #52272

February 22nd 2011

So the question needs to be asked – why are there two general perceptions? Why don’t all scientists, everywhere, share the same perception?

It would be a worry if scientists shared one perception. There is plenty of unsettled science left to argue about.

The non-teleologists don’t like the rabbit chasing.

The IDers insist on a good duck hunt.

Not sure who you are referring to as “non-teleologists” and how you have established what they don’t like. Teleology, I believe, is a philosophical concept about cause and purpose which doesn’t appear to be at all useful in science. What tangible contribution has any duck-hunting IDer made so far to human knowledge?


Rich - #52808

February 28th 2011

Alan Fox:

The tangible contribution that ID has made so far to human knowledge is to show that neo-Darwinism, in its unadulterated form, is an incredibly weak theory.  It is just as much a contribution to human knowledge to expose bad answers as it is to discover better ones.  Indeed, until people realize that there is something seriously defective about existing theories, they are unlikely to look for new ones.

The neo-Darwinist establishment (mostly older biologists now) is of course violently opposed to ID.  Naturally the Emperor will be opposed to the people who announce that he has no clothes.  But ID, by slowly weaning the public from neo-Darwinism, will make it easier for the non-neo-Darwinian biologists of the younger generation to gain a hearing.  Once you no longer regard Mayr, Dobzhansky and Fisher as untouchable deities who must not be criticized, you can listen to the ideas of Lynn Margulis, Stuart Newman, Richard Sternberg, Michael Denton, and others who want to take evolutionary theory in a non-Darwinian direction.  So even if ID fails to offer an adequate alternative account of origins, it has done a public service by helping to overthrow the 70-year-old rule of the graying tyrant.


Tim - #52810

February 28th 2011

Rich, when you claim that “neo-Darwinism” ... “is an incredibly weak theory” what exactly do you mean? Is it that the evidence for common descent is weak, that the evidence for natural selection as the main mechanism in driving the process is weak, or something else?  How has ID demonstrated what you claim it has? Where has it done so, and whom has it convinced? Apparently, not Todd Wood.


Rich - #52867

March 1st 2011

Tim:

I’ve explained on dozens of threads here what I mean by “neo-Darwinism” (aka the Modern Synthesis), and why I think it’s pathetically weak as a scientific theory, and I’m sure you’ve been present on some of them.  In any case, you can easily find my posts.  Just locate the discussions where ID people are being misrepresented and unfairly attacked.  (Yes, I know, that’s probably half the discussions on the site, but I mean where an ID person’s name is in the title.)

I aimed my comment at Alan Fox and only at him, as a parting shot.  I don’t wish to start a further conversation with you at this point.  That’s why I’m refraining from giving you my opinion of the overall importance of Todd Wood in the grand scheme of modern evolutionary thought.  It’s nothing personal, I just don’t have the time.  Best wishes.


Leigh Copeland - #71855

August 11th 2012

What I would appreciate is someone who can turn the light of evolutionary discoveries back upon itself.  Does all this amazing progress give any helpful hints how knowledge of this progress will progress?  Knowledge of evolution considered as a step in that very evolution?  Can we anticipate how evolutionary knowldege will spread by thinking of it as a new tool, or social structure or genetic modification, or what?  Would an analogy from the sapien displacement of neanderthal be a good metaphor for BioLogos displacing YEC, or ID, for example?


Page 1 of 1   1