My Evangelical Christian friend, Pastor Gregory Dickow, has often expounded the principle, “In the essential teachings, let there be unity, in the nonessential teachings, let there be liberty, and in all things, let there be charity.” For Dickow the essentials are that Christ died for your sins, and his blood was shed as a human sacrifice once and for all time to atone for all sins of humanity. Nonessentials are the points of sectarian disagreement (esp. the focus on petty subsequent sins after acceptance of Christ). Charity of course is love, the sort of love that should be exhibited by all Christians to all people, regardless of their sectarian differences. On his radio show, “Ask the Pastor” the other day I asked him where exactly the acceptance of evolution fit into this scheme, and if it was OK for Christians to come to such a conclusion.
Dickow answered that the acceptance of evolution does not award one a trip straight to hell on a greased pole. Because the only mortal sin that one can really have is the rejection of Christ, there might be many points of view that Christians can have that will not keep them out of heaven. I got the impression that he sort of expects believers to come around and eventually reject many of the perceived misconceptions that they might have as they “grow in Christ,” acceptance of evolution included. But as I hung up I thought that Dickow’s response seemed to represent a very interesting and satisfying admission coming from a biblical fundamentalist. I have listened to Christian radio quite a bit (more monitored it) to bear witness to the various machinations of the religious right, and in order to gain an understanding of what they tell each other in regards to the acceptance of evolutionary theory. Many of these folks spit God’s future vengeance on those that would even presume to give evolution a fair hearing, let alone accept it. For many you can’t be a Christian and accept evolution. But Dickow’s position is that Evangelical Christians can accept evolution, if tentatively, and not jeopardize their salvation. Wow. This man may be unique amongst fundamentalists, but many people listen to his radio show. I think he’s an influential man, if only regionally.
Dickow has often stated that the evidence of the historical Christ is incontrovertible, but also believes that adequate proof of evolution has not been established (“It’s only a theory, not fact”). I suspect that he has not spent the amount of time that would be required to review the comprehensive and multidisciplinary evidence for a rational person such as himself to come to the conclusion that evolution indeed has a factual basis. And like many creationists, the limited amount of time upon which he bases his seemingly certain conviction that evolution is “only theory, not fact” is spent on reviewing creationist literature. He may be specifically unaware of the deceit and duplicity exhibited by the Intelligent Design advocates that was exposed in a court of law in the Kitzmiller versus Dover case in 2005 (see Dawkins 2006 for a good account p. 157-160). For this reason many intelligent yet religious people will never critically review the best possible literature on the subject, that which is generated by the scientific community, which is readily available in our modern age of copious scientific information. I use Gregory Dickow as an example of the most rational Evangelical Christian that I know. So how can intelligent people reject evolution? What should be advocated to change that?
We all know that a staggering proportion of American populace does not accept evolution. But what can be done to change that such that evolution is finally seen for what it is, an actual process found in nature and the central unifying principle in biology? There’s a good review on the subject by Williams (2009). Williams cites a UK poll by a religious think tank that found that only 37% thought that evolution is a thoroughly established scientific theory, and 19% believe that it has little or no supporting evidence. He also cites Mazur (2008), whom posits that rejection of evolution is not a character flaw, but is a response to the social attachments developed early in life, and subsequent attachments to religious spouses, associates and friends. Many may secretly accept evolution or at least have enough savvy to realize that the religious right is certainly misrepresenting evolutionary theory, yet their social commitments may keep them from actively seeking out the scientific literature. Fear of rejection or ridicule by co-religionists are probably keeping many silent.
Williams quotes Duschl (2007), and states that the lack of acceptance of evolution stems from “the natural intuitive development of ‘creationist’ ideas as a very young child,” that the rejection of evolution comes from an “initial essentialist bias-that is, their initial tendency to believe that things have a true underlying nature (Williams quoting Duschl 2007).” Essentialist beliefs represent the sort of typological thinking (such as the creation of ‘kinds’ of organisms found in creation stories as in the bible) that was prevalent in the 19th century and a basis for early rejection of Darwinism (Mayr 2001). Williams also blames inadequate primary school education of evolutionary theory, the sloppy language that some scientists use that seems to imply design in the natural world (that creationists love to exploit), and even young science graduates inability to distinguish scientific theory, law, and fact. It’s no wonder that the general public confuses the difference between belief in a metaphysical position and acceptance of the factual basis of evolution. The answer as Williams correctly states would be to begin the education of evolutionary theory as early as possible in the public school curriculum. This very thing seems a very good possibility at least in England for this past November a bill was introduced into the British Parliament that will make the teaching of evolutionary theory compulsory in primary schools (Anonymous 2009).
The goal really is not to begrudge anyone their faith as long as science education is not impeded or waylaid by religious fundamentalism. Richard Dawkins and Christopher Hitchens suffer no fools and take no prisoners, and actively refute religious beliefs in order to change them. They would like to see religion neutered. If the goal is to break the nefarious hold that religion can have on society, then this is certainly a laudable position. At some point we would then bolster science education in the process. This seems to me a top-down strategy that, although satisfying to many atheistic ideologues, may not be particularly successful if a potentially more important and tangible goal of strengthening and advancing science education is desired. A more bottom-up strategy of early education would certainly diffuse some of the early misconceptions that children may develop. Williams and Dawkins (2006) claim that the targeting of youth by creationists even constitutes a form of intellectual child abuse, a charge that on the face of it seems pretty grave, but is difficult in my opinion to outright deny given some of the insidious tactics of ID crowd.
Evolution is taught to some degree in secondary schools, and at colleges and universities, and is widely promoted in museums and other institutions. But we have to admit that this influence has been insufficient as the high number of enemies of Darwinism in the U.S. attests to our failure to adequately defend and promote it. We must be careful, however, because early attempts in the courts to promote evolution education in the schools such as the Scopes Monkey Trial in 1925 lead to successful creationist strategies that stripped evolution from American textbooks and marginalized evolution education (Shermer 2006). On the other hand today such marginalization may not be quite as easy as modern texts are often written by experts and some are explicitly tackling the social milieu around creationism as in Evolution (Futuyma 2009).
Rationally convincing liberal Christian thinkers like the influential Gregory Dickow may help us gain some inroads into the hold that creationist dogma that Christian fundamentalists seem to have over many. Developing relationships with such individuals and getting them to realize and admit that evolutionary theory didn’t originate from the pit of hell is certainly a good start. Evolutionary theory is not responsible for Social Darwinism, all of social ills, or eugenics. The factual basis of evolution is in any case independent of its social implications. Liberal Christian thinkers may be reached if we take a more compassionate and reasoned approached. Only then can we diffuse the inevitable backlash that would come from advocating early childhood education of evolutionary theory.
References:
Anonymous. 2009. Evolution and history compulsory. BBC News. http://news.bbc.co.uk/2/hi/uk_news/education/8369172.stm
Duchl, RA, Schweingruber HA, and Shouse, AW. 2007. Taking Science to School: Learning and Teaching Science in Grades K-8. National Academies Press.
Futuyma, Douglas. Evolution. Sinauer Associates p. 609-633.
Dawkins, Richard. 2006. The God Delusion. Bantam Books.
Mayr, Ernst. 2001. What Evolution Is. Basic Books p. 74-75.
Mazur, A. 2008. Implausible Beliefs. Transaction Publishers p. 246.
Shermer, Michael. 2006. Why Darwin Matters. Henry Holt and Co.
Williams, James D. 2009. Belief versus acceptance: why people do not believe in evolution? BioEssays 31 pp. 1255-1262.
Sunday, January 3, 2010
Friday, November 27, 2009
Jerry Springer, Neo-Nazis, Ray Comfort, and Darwin
I don’t particularly want to spend a lot of time on this blog discussing the culture wars. There’s a fair amount of uninteresting hype in the blogosphere. My main interest is to have discussions within evolutionary theory but as I’ve a bum shoulder and am in a bit of pain, I don’t have the energy to research and write about one of the possible topics I had planned: determining the target of natural selection, epigenetics, a new LaMarkism? Stay tuned; these essays will follow soon. I will write soon also about Darwin’s Dilemma, the latest in the Discovery Institute’s lame attempt to try to legitimize intelligent design as science. I don’t really care to discuss creationist perspectives in terms of why they shouldn’t have equal time in the classroom or the hundred other reasons why they should just shut up and sit down, but if there is a way to use creationist hype to learn more about evolution, then I’m in. I also suppose that if my children’s and my grandchildren’s quality of science education didn’t hang in the balance, it wouldn’t be necessary.
I’m sure that many of you have heard about the new addition of Darwin’s Origin by Ray Comfort. And I’m also sure that if you had, you also have heard that it contains a creationist, propagandistic introduction that basically tells you not to believe any of Darwin’s ideas or that science has disproved all that the rest of the volume contains. I or any other evolutionist could take you through point by point and handily grind such drivel into the ground. But Darwin’s new bulldog, Richard Dawkins is doing a much better job than what I ever could. I’d rather like to make the point that I made to my wife after we sat through part of an episode of Jerry Springer.
Springer had on a group of Neo-Nazis, who as you might expect proceeded to rant about all things wrong about our society due to our willingness to accommodate minorities in America. Well Jerry is a sensationalist, and we all know that. But at the end of the episode he gave a very interesting justification for why he had these individuals on his show. He told us that it was important to allow these nuts to be front and center, and spout their nonsense. Yes you heard right; he was giving them the forum, but for a very interesting reason: Springer thought that we shouldn’t let these folks skulk in the background of guerilla politics. We should let them voice their opinion time to time, just so we could remember how crazy these people are.
That’s the way that I feel about Comfort and his introduction to the Origin. All the hype that his introduction produces may backfire on him. By focusing on college students, who probably accept evolution in far greater numbers than the American public at large, Comfort may be playing right into Dakin’s hands. It warms my heart to see free-thinking students rip that crap right out of their very special 150th edition of Origin. Many students who may even not understand that evolution is not a matter of belief, but acceptance of a process in nature may just be drawn to perhaps the most important book that has been published in the last 150 years. They will hear about the controversy, read the drivel, and then get to the Origin a little more sensitized to creationist nonsense. They will go to their biology professors and ask good questions. Their professors will have a wonderful context into which the teaching of evolution will be even more meaningful. Hopefully there will be plenty of our evolutionist brethren who can put evolutionary theory into context for them. And perhaps we can even thank a creationist for pointing them in the right direction rather than into the arms of anti-intellectual purveyors of nonsense.
I’m sure that many of you have heard about the new addition of Darwin’s Origin by Ray Comfort. And I’m also sure that if you had, you also have heard that it contains a creationist, propagandistic introduction that basically tells you not to believe any of Darwin’s ideas or that science has disproved all that the rest of the volume contains. I or any other evolutionist could take you through point by point and handily grind such drivel into the ground. But Darwin’s new bulldog, Richard Dawkins is doing a much better job than what I ever could. I’d rather like to make the point that I made to my wife after we sat through part of an episode of Jerry Springer.
Springer had on a group of Neo-Nazis, who as you might expect proceeded to rant about all things wrong about our society due to our willingness to accommodate minorities in America. Well Jerry is a sensationalist, and we all know that. But at the end of the episode he gave a very interesting justification for why he had these individuals on his show. He told us that it was important to allow these nuts to be front and center, and spout their nonsense. Yes you heard right; he was giving them the forum, but for a very interesting reason: Springer thought that we shouldn’t let these folks skulk in the background of guerilla politics. We should let them voice their opinion time to time, just so we could remember how crazy these people are.
That’s the way that I feel about Comfort and his introduction to the Origin. All the hype that his introduction produces may backfire on him. By focusing on college students, who probably accept evolution in far greater numbers than the American public at large, Comfort may be playing right into Dakin’s hands. It warms my heart to see free-thinking students rip that crap right out of their very special 150th edition of Origin. Many students who may even not understand that evolution is not a matter of belief, but acceptance of a process in nature may just be drawn to perhaps the most important book that has been published in the last 150 years. They will hear about the controversy, read the drivel, and then get to the Origin a little more sensitized to creationist nonsense. They will go to their biology professors and ask good questions. Their professors will have a wonderful context into which the teaching of evolution will be even more meaningful. Hopefully there will be plenty of our evolutionist brethren who can put evolutionary theory into context for them. And perhaps we can even thank a creationist for pointing them in the right direction rather than into the arms of anti-intellectual purveyors of nonsense.
Saturday, November 21, 2009
In Defense of Darwin
One of the reasons why I started this blog was so that an open discussion could be had on evolutionary theory and Darwin himself. Mostly I intended this to focus on areas of theory within evolutionary biology, but also recognize that this could also be a tool for a clarification and explanation of evolutionary principles to a wider audience that could include scientists outside the field of biology and the public. To that end I’d like to respond to some comments that someone left in the blog about Darwin and evolution. I hope this individual does not take offense because I disagree, but at least welcomes the discussion that I will try to keep respectful.
Comment:
“Of course most of (Darwin’s) initial observations have been disproved (for example his observation on black moths in England- now there are no black moths only white so his observations proved nothing more, or less, than it is easier to eat black moths on a white background and white moths on a black background...there is no evidence of macro evolution there)… I am a convinced micro evolutionist btw, on the macro level I see too many disconnects to fully accept his theory.”
Answer:
If Darwin was mistaken in his early career, it was that it took him until the 1840’s before he came to the conclusion that the diversity of life was not a product of intelligent design, but that evolution proceeds by natural causes. He read the argument for design in the analogy of the watch by Paley (1809), and was influenced by him…early on. It may be easy to try to say that a scientist was wrong about certain things, especially early in his or her career. I don’t think that’s a very fair argument. I would be surprised if a young scientist was never wrong. And even if an old one was allegedly never wrong, I would find that highly suspect. The fact that remains is Darwin’s theory of evolution has not been falsified, which by definition continues to make it a viable theory. We have such an overwhelming evidence for biological evolution that we can characterize it as Ernst Mayr has as a description of a process in nature.
In terms of the scientific value of Darwin’s early work we can look to his first scientific book after his return from his voyage on the Beagle was centered on his observations of coral. He correctly recognized three stages of coral reef development: fringing reefs, barrier reefs, and atolls (1842). His initial hunch that artificial selection of domesticated animals and plants is a type of evolution that mirrors natural selection was correct. Sure Darwin wasn’t right about everything. Probably the worst theoretical misstep Darwin had was his theory of Pangenesis later in his career (1868) in which he incorrectly surmised a process for inheritance. But no reliable authority chides him for not knowing where the first step in natural selection, variation, comes from. It wasn’t until the rediscovery of Mendel’s work and the Modern Synthesis that a fuller understanding could be obtained. It remains that the majority consensus still rests in Darwin’s multi-component edifice for evolution (common decent, transmutation or speciation, uniformitarianism, and natural selection-Mayr 2001). It’s popular rhetorical device to take swipes at Darwin so that the full, perhaps unpalatable, implications of evolutionary theory are diminished if the founding father had flaws. Stephen Jay Gould in The Structure of Evolutionary Theory (2002) gives a very good account of this phenomenon:
“We must rank challenges by their degree of engagement with the Darwinian core; we cannot follow a strategy of mindless “raw empiricism” towards the Origin and simply compile a list of Darwin’s mistakes. All great works are bursting with error; how else could true creativity be achieved? Could anyone possibly reformulate a universe of thought and get every detail right the first time? “We should not simply count Darwin’s errors, but rather assess their importance relative to his essential postulates. (Consider, for example the standard rhetorical, and deeply anti-intellectual, ploy of politically motivated and destructive critics, American creationists in particular. They just list the mistakes, envelop each in a cloud of verbal mockery, and pretend that the whole system has drowned in this tiny puddle of inconsequential error.)”
I don’t know of any of Darwin’s errors that change the fact that he was correct in his core theories of the totality of evolution. But what about this business of industrial melanism being an error of Darwin’s? I wasn’t aware that Darwin was the first or at least early describer of industrial melanism. I did a little digging into the literature, and could find no direct reference that cites Darwin being involved in any of the early investigations. Steward (1977) states that although the first Biston betularia carbonaria (black phenotype with B. betularia typica being the white phenotype) was caught in Manchester, England in 1848, but wasn’t reported until 1864 by Edelston. After moving to Down House in the 1840’s Darwin rarely left predominantly due to ill health. His home was in the countryside. It is doubtful that Darwin observed industrial melanism, but may have heard about it. I would be interested in any references to that effect. Modern literature on the subject deals with bird predation of the peppered moth in industrial areas in England in the 1950’s (Kettlewell 1973).
I did some surfing on the internet and I did find information about industrial melanism. Interesting that many of the sites were creationist, and were attacking the example of industrial melanism as a textbook example of evolution. The two things that were continually repeated were that the research was a fraud because Kettlewell apparently glued dead moths to a tree for a photo that was published along with his paper. I am fairly certain that Kettlewell had no intention to deceive anyone by this act. It was simply a visual aid to show how well camouflaged the dark moths were. Remember his research took place in the 1950’s; and I imagine it would be very difficult to create a good resolution picture without immobilizing the subject. Besides the photo did nothing to falsify the observations of the original research, which subsequently was reproduced by others.
The other error in this comment was that if industrial melanism is discredited, then it’s not an example of macroevolution. First of all this “icon” of evolution was never intended to be an example of speciation. Industrial melanism has been cited in numerous biology textbooks rightly because it is an example of natural selection. There is a natural variability in phenotypic expression in peppered moths such that some moths were darker than others. Birds could not see the darker moths on soot-stained trees, and gobbled up the lighter colored moths. So dark moths were selected naturally. It’s a simple, elegant example of variation and selection, the core of Darwin’s theory. It’s popular in the creationist literature to try to make a distinction between micro- and macro-evolution with some accepting the former, but not the latter. The reason is simple. It’s virtually impossible to ignore the findings of modern molecular biology, which support evolution at the level of gene frequencies and genetic regulation that affects the phenotypically expressed individual, which is what is presented to the natural environment for selection. But creationists won’t accept phylogeny; that is they find it impossible to reconcile the biblical version of creation in which God created “kinds” of animals with Darwin’s alternative explanation, in which variation and selection results in adaptations and speciation. Morphological changes can accumulate as each successive species unfold in a lineage. Eventually these exhibit characteristics and morphological adaptations to allow the taxonomist to detect enough of a difference from that which has been previously described to feel that a new category is necessary. In the fossil record it is the descendent species from the earlier one that allows us to see that a new genera or family might have been initiated.
For creationists it’s harder to deny the findings of modern molecular biology in which a deluge of research findings indicate that natural selection chooses successful individuals that have a particular phenotype that can be demonstrated to have adaptive value. Populations beget others usually at the periphery of the species range. Once reproductively isolated, these are considered new species by definition. You might try to argue then that it’s as far as evolution can go. If you are intellectually committed to a sacred text that specifically states that all of life was created in a matter of days with each “kind” of creature being separately created, then it’s a lot harder to accept speciation and phylogeny. Perhaps you can accept speciation, but not phylogeny (macroevolution); then you are stuck, however, because once you accept the fact that speciation occurs, you don’t have to go any further intellectually to accept phylogeny. There are really no “kinds” of organisms. They are simply the current endpoints in lineages. Darwin showed us that evolution acts upon populations, not abstract essences that don’t exist in nature. There is no compelling indication that the evolutionary mechanisms found in microevolution cannot explain what is termed “macroevolution.” It’s the same process. This fact could be the subject of an essay in of itself, so I’ll move on.
Comment:
“Well of course (Darwin’s) original theory is pretty well shot what we now have posited is Neo Darwin...but you know that I am sure.”
Answer:
I’m not sure if our commentator is saying that Neo-Darwinism discredited industrial melanism, if it contradicts Darwin’s alleged observation of melanism, or if it supposed to negate all five sub-theories of evolution that are contained in Darwin’s “original theory.” I’ve already addressed the peppered moth specifically. The Modern Synthesis from which the Neo-Darwinist school sprung specifically vindicated Darwin. Yes that is the case. Scientists like Mayr, Simpson, and Dobzhansky reconciled the findings of the geneticists after Mendel’s work was rediscovered with natural selection. The secret of heredity was deciphered, and was identified as the source of variation on which selection acts. After 1859 some components of Darwin’s theory (common descent, speciation, diversification, and uniformitarianism) were accepted, but the mechanism of evolution, natural selection wasn’t accepted until the source of variation could be explained after the rediscovery of Mendel. Adaptations were thus explained, and were in total agreement with Darwin’s thesis. That’s why it is called the Modern Synthesis.
Comment:
“Another interesting "fact" is a study done on the acceptance of Macro evolution as fact among scientists and engineers. The "soft' scientists (biologists chemists etc) are four to five more times as likely to accept macro evolution as fact than the hard scientists (engineers, physics, etc). What amazed the researchers (and I will point you to the study when I get a chance) was the relatively high number of scientist and engineers (most of these were the "hards") that did not accept Macro Evolution as fact. (I think it was almost 40% who considered themselves Evolutionary agnostics)”
Answer:
I’m not sure that chemists would agree that they are “soft.” They are all about positing reaction mechanisms on the molecular level and testing their ideas statistically to determine if the proposed mechanism matches their predictions. Like wise I’m not so sure biologists would feel this way. Of course I have my own prejudices, and when I think of soft science I think of psychology and sociology, so perhaps shame on me. I’m not sure that the study specifically made the hard vs. soft distinction, but it does not surprise me at all that engineers or physicists are agnostic where evolution is concerned. Actually I take exception of the use of the term agnostic as it regards any scientific theory, because it implies that you can believe or disbelieve anything in science. In the analysis of data, evidence either supports a theory and therefore should be accepted, or does not support it and so should be rejected. Belief is irrelevant.
So I’m not surprised. If you move away from the field of evolutionary biology you very quickly find individuals who may not be aware of or understand how the evidences support evolutionary theory. Outside the circle of evolutionary biologists, physical scientists and the general public may have a hard time understanding how the actual natural history of organisms unfolded. Some engineers or physicists may have religious intellectual commitments that they can hold that aren’t inconsistent with their disciplines, while others scientists might simply have a problem with any science like biology or geology that to some extent relies on historical narrative. But let me make this perfectly clear. Biology is not (or at least is no longer) a soft science. Literature in biology is rife with statistical and computational analysis as in population biology. Darwinian evolution has not been falsified, and has been confirmed my multiple, independent lines of evidence from multiple fields of science. The argument that evolution is not empirical is a mischaracterization. To be sure not every field of science can be easily described by mathematics or amenable to laboratory investigation. But even in the laboratory we see that evolution has been vindicated in the form of “microevolution,” which explains phylogeny very well. To be sure it is extremely difficult to see new genera or families being born; such things could take thousands or millions of years. But we see changes in gene frequencies, we see how the phenotype is generated in ontogeny with variation on which selection acts, and we have morphological evidence from the study of extant and fossil species. Neo-Darwinism may even be considered to have hardened too much according to Steven Jay Gould.
In my previous essay, “How Can Evolution Inform Us in Predicting Extraterrestrial intelligence,” I discuss how it is predominantly astronomers, astrophysicists, and perhaps planetary scientists who may be assuming that intelligent life is rampant. I explain that a simplistic argument is employed and many have jumped on the bandwagon of egregious speculation. Not knowing how unlikely was the course of evolution that unfolded on our own planet was, somewhat wild speculation becomes the order of the day. Howard Gest of Indiana University says much the same thing. In his essay in the bulletin of the American Society of Microbiology (2005), he tells us that when he was asked to be on the Martian Meteorite Working Group organized by the Lunar and Planetary Institute in Houson, Texas after it was reported that the meteorite ALH4001 had potential signs of life, he found that he was the only biologist in attendance. So it may be easy for some scientist to be unsure of evolution if they haven’t consulted the proper authorities in biology or not have taken the time to really evaluate the wealth of evidence for evolution. That is truly soft thinking if there ever was.
Thanks to TIKTOK1984 for giving us something to talk about today. I’ve hoped that I’ve helped to clarify the matter from a biologist’s viewpoint.
Darwin, C. 1868. The Variation of Animals and Plants Under Domestication 2 vols. Murray, London.
Gest, H. 2005. “Microbes in the Search for Extraterrestrial Life.” ASM News 71:12 pp.560-561.
Gould, S. J. 2002. The Stucture of Evolutionary Theory. Belknap Press, Cambridge.
p. 168.
Kettlewell, B. 1973. The Evolution of Industrial Melanism. Clarendon Press.
Mayr, E. 2001. What Evolution Is. Basic Books, New York. p. 86.
Paley, W. 1809. Natual Thology: Or Evidences of the Existence and Attributes of the Deity. J. Faulder, London.
Steward, R.C. (1977). "Industrial and non-industrial melanism in the peppered moth Biston betularia (L.)", Ecological Entomology 2 (pp. 231–243).
Comment:
“Of course most of (Darwin’s) initial observations have been disproved (for example his observation on black moths in England- now there are no black moths only white so his observations proved nothing more, or less, than it is easier to eat black moths on a white background and white moths on a black background...there is no evidence of macro evolution there)… I am a convinced micro evolutionist btw, on the macro level I see too many disconnects to fully accept his theory.”
Answer:
If Darwin was mistaken in his early career, it was that it took him until the 1840’s before he came to the conclusion that the diversity of life was not a product of intelligent design, but that evolution proceeds by natural causes. He read the argument for design in the analogy of the watch by Paley (1809), and was influenced by him…early on. It may be easy to try to say that a scientist was wrong about certain things, especially early in his or her career. I don’t think that’s a very fair argument. I would be surprised if a young scientist was never wrong. And even if an old one was allegedly never wrong, I would find that highly suspect. The fact that remains is Darwin’s theory of evolution has not been falsified, which by definition continues to make it a viable theory. We have such an overwhelming evidence for biological evolution that we can characterize it as Ernst Mayr has as a description of a process in nature.
In terms of the scientific value of Darwin’s early work we can look to his first scientific book after his return from his voyage on the Beagle was centered on his observations of coral. He correctly recognized three stages of coral reef development: fringing reefs, barrier reefs, and atolls (1842). His initial hunch that artificial selection of domesticated animals and plants is a type of evolution that mirrors natural selection was correct. Sure Darwin wasn’t right about everything. Probably the worst theoretical misstep Darwin had was his theory of Pangenesis later in his career (1868) in which he incorrectly surmised a process for inheritance. But no reliable authority chides him for not knowing where the first step in natural selection, variation, comes from. It wasn’t until the rediscovery of Mendel’s work and the Modern Synthesis that a fuller understanding could be obtained. It remains that the majority consensus still rests in Darwin’s multi-component edifice for evolution (common decent, transmutation or speciation, uniformitarianism, and natural selection-Mayr 2001). It’s popular rhetorical device to take swipes at Darwin so that the full, perhaps unpalatable, implications of evolutionary theory are diminished if the founding father had flaws. Stephen Jay Gould in The Structure of Evolutionary Theory (2002) gives a very good account of this phenomenon:
“We must rank challenges by their degree of engagement with the Darwinian core; we cannot follow a strategy of mindless “raw empiricism” towards the Origin and simply compile a list of Darwin’s mistakes. All great works are bursting with error; how else could true creativity be achieved? Could anyone possibly reformulate a universe of thought and get every detail right the first time? “We should not simply count Darwin’s errors, but rather assess their importance relative to his essential postulates. (Consider, for example the standard rhetorical, and deeply anti-intellectual, ploy of politically motivated and destructive critics, American creationists in particular. They just list the mistakes, envelop each in a cloud of verbal mockery, and pretend that the whole system has drowned in this tiny puddle of inconsequential error.)”
I don’t know of any of Darwin’s errors that change the fact that he was correct in his core theories of the totality of evolution. But what about this business of industrial melanism being an error of Darwin’s? I wasn’t aware that Darwin was the first or at least early describer of industrial melanism. I did a little digging into the literature, and could find no direct reference that cites Darwin being involved in any of the early investigations. Steward (1977) states that although the first Biston betularia carbonaria (black phenotype with B. betularia typica being the white phenotype) was caught in Manchester, England in 1848, but wasn’t reported until 1864 by Edelston. After moving to Down House in the 1840’s Darwin rarely left predominantly due to ill health. His home was in the countryside. It is doubtful that Darwin observed industrial melanism, but may have heard about it. I would be interested in any references to that effect. Modern literature on the subject deals with bird predation of the peppered moth in industrial areas in England in the 1950’s (Kettlewell 1973).
I did some surfing on the internet and I did find information about industrial melanism. Interesting that many of the sites were creationist, and were attacking the example of industrial melanism as a textbook example of evolution. The two things that were continually repeated were that the research was a fraud because Kettlewell apparently glued dead moths to a tree for a photo that was published along with his paper. I am fairly certain that Kettlewell had no intention to deceive anyone by this act. It was simply a visual aid to show how well camouflaged the dark moths were. Remember his research took place in the 1950’s; and I imagine it would be very difficult to create a good resolution picture without immobilizing the subject. Besides the photo did nothing to falsify the observations of the original research, which subsequently was reproduced by others.
The other error in this comment was that if industrial melanism is discredited, then it’s not an example of macroevolution. First of all this “icon” of evolution was never intended to be an example of speciation. Industrial melanism has been cited in numerous biology textbooks rightly because it is an example of natural selection. There is a natural variability in phenotypic expression in peppered moths such that some moths were darker than others. Birds could not see the darker moths on soot-stained trees, and gobbled up the lighter colored moths. So dark moths were selected naturally. It’s a simple, elegant example of variation and selection, the core of Darwin’s theory. It’s popular in the creationist literature to try to make a distinction between micro- and macro-evolution with some accepting the former, but not the latter. The reason is simple. It’s virtually impossible to ignore the findings of modern molecular biology, which support evolution at the level of gene frequencies and genetic regulation that affects the phenotypically expressed individual, which is what is presented to the natural environment for selection. But creationists won’t accept phylogeny; that is they find it impossible to reconcile the biblical version of creation in which God created “kinds” of animals with Darwin’s alternative explanation, in which variation and selection results in adaptations and speciation. Morphological changes can accumulate as each successive species unfold in a lineage. Eventually these exhibit characteristics and morphological adaptations to allow the taxonomist to detect enough of a difference from that which has been previously described to feel that a new category is necessary. In the fossil record it is the descendent species from the earlier one that allows us to see that a new genera or family might have been initiated.
For creationists it’s harder to deny the findings of modern molecular biology in which a deluge of research findings indicate that natural selection chooses successful individuals that have a particular phenotype that can be demonstrated to have adaptive value. Populations beget others usually at the periphery of the species range. Once reproductively isolated, these are considered new species by definition. You might try to argue then that it’s as far as evolution can go. If you are intellectually committed to a sacred text that specifically states that all of life was created in a matter of days with each “kind” of creature being separately created, then it’s a lot harder to accept speciation and phylogeny. Perhaps you can accept speciation, but not phylogeny (macroevolution); then you are stuck, however, because once you accept the fact that speciation occurs, you don’t have to go any further intellectually to accept phylogeny. There are really no “kinds” of organisms. They are simply the current endpoints in lineages. Darwin showed us that evolution acts upon populations, not abstract essences that don’t exist in nature. There is no compelling indication that the evolutionary mechanisms found in microevolution cannot explain what is termed “macroevolution.” It’s the same process. This fact could be the subject of an essay in of itself, so I’ll move on.
Comment:
“Well of course (Darwin’s) original theory is pretty well shot what we now have posited is Neo Darwin...but you know that I am sure.”
Answer:
I’m not sure if our commentator is saying that Neo-Darwinism discredited industrial melanism, if it contradicts Darwin’s alleged observation of melanism, or if it supposed to negate all five sub-theories of evolution that are contained in Darwin’s “original theory.” I’ve already addressed the peppered moth specifically. The Modern Synthesis from which the Neo-Darwinist school sprung specifically vindicated Darwin. Yes that is the case. Scientists like Mayr, Simpson, and Dobzhansky reconciled the findings of the geneticists after Mendel’s work was rediscovered with natural selection. The secret of heredity was deciphered, and was identified as the source of variation on which selection acts. After 1859 some components of Darwin’s theory (common descent, speciation, diversification, and uniformitarianism) were accepted, but the mechanism of evolution, natural selection wasn’t accepted until the source of variation could be explained after the rediscovery of Mendel. Adaptations were thus explained, and were in total agreement with Darwin’s thesis. That’s why it is called the Modern Synthesis.
Comment:
“Another interesting "fact" is a study done on the acceptance of Macro evolution as fact among scientists and engineers. The "soft' scientists (biologists chemists etc) are four to five more times as likely to accept macro evolution as fact than the hard scientists (engineers, physics, etc). What amazed the researchers (and I will point you to the study when I get a chance) was the relatively high number of scientist and engineers (most of these were the "hards") that did not accept Macro Evolution as fact. (I think it was almost 40% who considered themselves Evolutionary agnostics)”
Answer:
I’m not sure that chemists would agree that they are “soft.” They are all about positing reaction mechanisms on the molecular level and testing their ideas statistically to determine if the proposed mechanism matches their predictions. Like wise I’m not so sure biologists would feel this way. Of course I have my own prejudices, and when I think of soft science I think of psychology and sociology, so perhaps shame on me. I’m not sure that the study specifically made the hard vs. soft distinction, but it does not surprise me at all that engineers or physicists are agnostic where evolution is concerned. Actually I take exception of the use of the term agnostic as it regards any scientific theory, because it implies that you can believe or disbelieve anything in science. In the analysis of data, evidence either supports a theory and therefore should be accepted, or does not support it and so should be rejected. Belief is irrelevant.
So I’m not surprised. If you move away from the field of evolutionary biology you very quickly find individuals who may not be aware of or understand how the evidences support evolutionary theory. Outside the circle of evolutionary biologists, physical scientists and the general public may have a hard time understanding how the actual natural history of organisms unfolded. Some engineers or physicists may have religious intellectual commitments that they can hold that aren’t inconsistent with their disciplines, while others scientists might simply have a problem with any science like biology or geology that to some extent relies on historical narrative. But let me make this perfectly clear. Biology is not (or at least is no longer) a soft science. Literature in biology is rife with statistical and computational analysis as in population biology. Darwinian evolution has not been falsified, and has been confirmed my multiple, independent lines of evidence from multiple fields of science. The argument that evolution is not empirical is a mischaracterization. To be sure not every field of science can be easily described by mathematics or amenable to laboratory investigation. But even in the laboratory we see that evolution has been vindicated in the form of “microevolution,” which explains phylogeny very well. To be sure it is extremely difficult to see new genera or families being born; such things could take thousands or millions of years. But we see changes in gene frequencies, we see how the phenotype is generated in ontogeny with variation on which selection acts, and we have morphological evidence from the study of extant and fossil species. Neo-Darwinism may even be considered to have hardened too much according to Steven Jay Gould.
In my previous essay, “How Can Evolution Inform Us in Predicting Extraterrestrial intelligence,” I discuss how it is predominantly astronomers, astrophysicists, and perhaps planetary scientists who may be assuming that intelligent life is rampant. I explain that a simplistic argument is employed and many have jumped on the bandwagon of egregious speculation. Not knowing how unlikely was the course of evolution that unfolded on our own planet was, somewhat wild speculation becomes the order of the day. Howard Gest of Indiana University says much the same thing. In his essay in the bulletin of the American Society of Microbiology (2005), he tells us that when he was asked to be on the Martian Meteorite Working Group organized by the Lunar and Planetary Institute in Houson, Texas after it was reported that the meteorite ALH4001 had potential signs of life, he found that he was the only biologist in attendance. So it may be easy for some scientist to be unsure of evolution if they haven’t consulted the proper authorities in biology or not have taken the time to really evaluate the wealth of evidence for evolution. That is truly soft thinking if there ever was.
Thanks to TIKTOK1984 for giving us something to talk about today. I’ve hoped that I’ve helped to clarify the matter from a biologist’s viewpoint.
Darwin, C. 1868. The Variation of Animals and Plants Under Domestication 2 vols. Murray, London.
Gest, H. 2005. “Microbes in the Search for Extraterrestrial Life.” ASM News 71:12 pp.560-561.
Gould, S. J. 2002. The Stucture of Evolutionary Theory. Belknap Press, Cambridge.
p. 168.
Kettlewell, B. 1973. The Evolution of Industrial Melanism. Clarendon Press.
Mayr, E. 2001. What Evolution Is. Basic Books, New York. p. 86.
Paley, W. 1809. Natual Thology: Or Evidences of the Existence and Attributes of the Deity. J. Faulder, London.
Steward, R.C. (1977). "Industrial and non-industrial melanism in the peppered moth Biston betularia (L.)", Ecological Entomology 2 (pp. 231–243).
Sunday, November 15, 2009
How Can Evolution Inform Us in Predicting Extraterrestrial Intelligence?
There’s nothing like a good sparring match among evolutionists. The skeptic Michael Shermer in his Nov. 2009 column in Scientific American comments that the likelihood of extraterrestrials with intelligence that are also humanoid is very small, perhaps only one other in the universe. Richard Dawkins disagrees, and reminds Shermer that Cambridge paleontologist S. C. Morris thinks that intelligent aliens would be “in effect bipedal primates” and Harvard University biologist Ed Wilson thinks that dinosaurs could have evolved into a humanoid type if the Alvarez impact never occurred. Shermer spars back, “If something like a smart, technological, bipedal humanoid has a certain level of inevitability because of how evolution unfolds, then it would have happened more than once here.” Shermer goes on to quote Ernst Mayr (2001), “Nothing demonstrates the improbablility of the origin of high intelligence better than the millions of phyletic lineages that failed to achieve it.” But then Dawkins responds that the universe is so big, and has so many inhabitable planets (presumably e.g. something like the Drake Equation), there must be more than a few humanoid civilizations.
I don’t know exactly where to begin. There is something wrong here on so many levels. The first is the hypothetical, “a certain level of inevitability because how evolution unfolds…” I’m not so sure that there is anything inevitable in evolution. I know that Shermer gave this as a hypothetical scenario, and probably doesn’t really accept this, but it sounds like Dawkins takes the bait. But we should know that any allegedly directional evolutionary trends “sooner or later either change direction or even reverse themselves (Mayr 2001).” If we see any trends at all it is just along the lines of what we know from evo-devo or Steven Jay Gould (2002), what we really see are the constraints of previous phylogenic histories that gave rise to developmental regulation in ontogeny.
But Morris and Wilson want to go beyond that and bemuse themselves that there may be some essential or directional push to become humanoid as if intelligence precludes that you must be bipedal, even a primate? I thought that orthogenesis was thoroughly refuted by the Modern Synthesis at least fifty years ago as again Mayr (2001) reminds us. There are no types. Being human is an endpoint in our lineage; that is all. There’s a certain logic to the assumption that an intelligent technologically advanced creature would have appendages that can manipulate objects with precision as in the grip afforded by the human opposable thumb. But bipedalism and opposability aren’t inevitable. I could understand why some might try work in some kind of directionality to evolution if one can’t divorce their biology from their theology, but let’s not even go there.
Extreme forms of this argument can be found in articles like that written by the planetary scientist Nancy Kiang in the April 2008 issue of Scientific American. Come let’s speculate on what plants would look like on other planets. Plants? We might as well ask what kind of vertebrate, what kind of tetrapod, what kind of reptile or amphibian, what kind of humanoid might we find? Did we forget of all the fits and starts and reverses that evolution took that resulted in terrestrial plants on Earth? Lynn Margulis reminds us (1998) that if it wasn’t for symbiotic fungi, there wouldn’t be any bloody plants. Plants aren’t inevitable, aren’t a type with an essence of autotrophism.
OK so it’s inevitable that there might be many intelligent life forms out there even if they’re not human? Even the skeptic Shermer concedes to this; Dawkins tries to remind us that the size of the universe might make it so. I just think that there is a certain simplicity here that seems to neglect how we really might begin to be able to calculate such a probability. We are constantly reminded that we really can’t do such a thing, but then we leap to the assumption that will be in favor of plenty of aliens to populate our potentially real Star Trek universe. There’s just an eerie resemblance to the simplistic argument for intelligent design…something like, “Creation is so complex, it must have been designed supernaturally.” If we oversimplify we end up with argument like that. Even if we can’t really calculate such a thing, I’d like to clarify at least what we need to consider before we even make such assumptions.
Even if you expect from a very similar basic imput of pre-biotic chemicals, life may have a certain probability, we are still at level of our prokaryotes. The expectation that complex multicellular life, then even human life, has some sort of probabilistic inevitability needs to be analyzed more than just superficially and in the context of the history of evolutionary theory.
Stereoscopic vision and opposable thumbs were probably adaptations to an arboreal life. Bipedalism may have been adaptation for locomotion for such a tree-loving creature after its environment started changing from forest to savannah. The human mind might be the result of emergent properties of the existing nervous system of hominids that were coapted to exploit an ever changing and complicated social landscape. Did we obtain these things through a directed process that inevitably resulted in a primate and a genus like Homo? Or do environments mold organisms into reoccurring, recognizable shapes that makes it likely that aliens would be recognizable to us as humanoid or even just multicellular? Just how inevitable are all these transitions?
The answer might lie in what I would call Critical Contingency Factors (CCFs) in the natural history of our planet. CCFs inform us how we think about the historical and contingent nature of biological evolution, and might allow us to begin to give more respect to what kind of evidence we would need to even begin to speculate about the frequency of life, even intelligent life on other planets.
Symbiotic Theory and Coevoltution. Perhaps the strongest argument for contigency in evolution is Symbiosis, two or more organisms that create an association sometimes intimately and permanently. Lynn Sagan (Margolis) in her historic paper (1969) on symbiosis demonstrated that the speculations of scientists as early as the late 19th century ( e.g. Schimper, 1883) had foundation, namely that some eukaryotic cellular organelles started out as prokaryotes, which associated with other prokaryotes and early eukaryotes to form the first unicellular animal and plant cells. For plants their precursors, algae, had to symbiotically associate with cyanobacteria (became chloroplasts) in order to photosynthesize. Before that critical event this organism already had another symbiont, the purple bacteria (became mitochondria), which made it possible to produce much energy in an atmosphere that was becoming ever more oxygenated (2 billion yrs. BP). Margolis developed her theory of symbiogenesis over the course of the next twenty years before the consensus caught up with her. By the time she published Symbiotic Planet (1998), she had the advantage of providing many, many examples beyond mitochondria and plastids of symbiotic associations that affected speciation events, changed lineages, creating even new genera. The point is that all of these events are completely unpredictable and contingent. Even the first eukaryotes are the product of both strict Darwinian evolution and symbiogenesis. The caveat here is that once the symbionts established a permanent relationship, subsequent change required natural selection per Darwin as Ernst Mayr reminded us in the forward to Margolis’ book. As for coevolution many organisms have evolved to keep in step with, to outcompete, and have arms races with other organisms that may not even be in the same domain, kingdom, phylum, etc. There’s no predicting what future associations organisms may have that affect their subsequent evolution.
Catastrophism. There have been as many as five previous global mass extinctions of life, not to mention the inevitably more numerous regional cataclysms (Gould 2002). It was just such events that remind us of the contingent nature of our natural history, and the affect that such events might inevitably have on the course of the evolution that ultimately created the diversity of life on Earth that man has been given the privilege to witness over the last 200,000 years. There is no way to predict what the future evolutionary path of any taxon could be after such events. New habitats open up if a major clade goes extinct. Unoccupied niches mean the potential of new adaptive zones. It is often stated that there never would have been the Age of Mammals if it hadn’t been for the extinction of the dinosaurs, which the consensus of the scientific community is
Emergence. It has often been remarked that the sort of intelligent cognition that humans have may be an emergent property of the evolution of our nervous system. All throughout the history of evolution at different turning points that beget perhaps a new genus, family, order, or class, biological systems that operate far out of equilibrium (as in Kaufmann 1993) make a biological-organizational leap to a new state of equilibrium upon which natural selection can shape further. Such events may mark the genesis of new adaptive radiations. Other examples might include:
1. Hypercyles of RNA that learn to replicate at first with first fidelity and then selectively evolve until some cycles approach the edge of thermodynamic equilibrium until a final snap into place, which marks a new metabolic efficiency that also just happens to inadvertently include a cellular membrane…the origin of life.
2. Genetic regulation in single cell eukarotes that at first aggregate as individuals, then reorganize the sort of phenotypic expression that allows for a division of labor amongst colonies…the birth of multicellularity…achieved perhaps by the push or pull of duplicated genes that maintain the old phenotypic expression as well as affect ontogeny in different ways as they mutate.
3. Genetic regulation in small, allopatric populations that as inbreeding continues, a loosening of the genotype occurs such that new pleiotropic regulatory networks are formed…typical speciation events at the micro/macroevolutionary divide.
All these scenarios start at the point of already having prokaryotic life, except for CCF Emergence #1. There are numerous more CCFs that precede the evolution of the first cell. I won’t go into those here but is interesting to mention that we can bring into the argument the same factors that creationists discuss, scenarios in which the conditions that allowed life to exist in our universe are very improbable. “Old Earth” creationist Hugh Ross in his book The Creator and the Cosmos (2001) discusses the many factors that reduce the possibility of ET life: large planets close enough, but not so far away that act as cosmic vacuum cleaners (e.g. Jupiter and Saturn in our solar system), and reduce the likelihood of asteroid and comet impacts on potentially habitable planets; our one moon allows a relatively reasonable wobble to our planet’s rotation; a habitable planet is one that is in the sweet spot in its solar system; the solar system has to be in a sweet spot in its galaxy; and many other points. Ironic to use a creationist argument, n'est-ce pas?
Many milestones in the evolution of life may have been the result of contigent, emergent properties that lead to new levels of biological organization. None of these turning points in our natural history were inevitable or predictable. Multicellular life may be very, very rare in the universe. We must be wary of any attempts to argue that there are inevitable progressions in evolution or some essence that is humanoid that MUST naturally occur on this or any other planet. I may have out-skeptified Michael Shermer.
References
Gould, S. J. (2002). The Stucture of Evolutionary Theory. Belknap Press, Cambridge.
Kaufmann, S.A. (1993). The Origins of Order. Oxford University Press, Oxford.
Kiang, N.Y. (Apr. 2008). “The color of plants on other worlds.” Sci. Am.
Margolis, L. (1998). Symbiotic Planet. Basic Books, New York.
Mayr, E. (2001). What evolution is. Basic Books, New York.
Ross, Hugh (2001). Creator and the cosmos. Navpress, Baltimore.
Schimper AFW (1883). "Über die Entwicklung der Chlorophyllkörner und Farbkörper". Bot. Zeitung 41: 105–14, 121–31, 137–46, 153–62.
Sagan (Margolis), L. (1967). "On the origin of mitosing cells". J Theor Bio. 14 (3): 255–274
Shermer, M. (Nov. 2009). Will ET look like us? Sci. Am. p. 36.
I don’t know exactly where to begin. There is something wrong here on so many levels. The first is the hypothetical, “a certain level of inevitability because how evolution unfolds…” I’m not so sure that there is anything inevitable in evolution. I know that Shermer gave this as a hypothetical scenario, and probably doesn’t really accept this, but it sounds like Dawkins takes the bait. But we should know that any allegedly directional evolutionary trends “sooner or later either change direction or even reverse themselves (Mayr 2001).” If we see any trends at all it is just along the lines of what we know from evo-devo or Steven Jay Gould (2002), what we really see are the constraints of previous phylogenic histories that gave rise to developmental regulation in ontogeny.
But Morris and Wilson want to go beyond that and bemuse themselves that there may be some essential or directional push to become humanoid as if intelligence precludes that you must be bipedal, even a primate? I thought that orthogenesis was thoroughly refuted by the Modern Synthesis at least fifty years ago as again Mayr (2001) reminds us. There are no types. Being human is an endpoint in our lineage; that is all. There’s a certain logic to the assumption that an intelligent technologically advanced creature would have appendages that can manipulate objects with precision as in the grip afforded by the human opposable thumb. But bipedalism and opposability aren’t inevitable. I could understand why some might try work in some kind of directionality to evolution if one can’t divorce their biology from their theology, but let’s not even go there.
Extreme forms of this argument can be found in articles like that written by the planetary scientist Nancy Kiang in the April 2008 issue of Scientific American. Come let’s speculate on what plants would look like on other planets. Plants? We might as well ask what kind of vertebrate, what kind of tetrapod, what kind of reptile or amphibian, what kind of humanoid might we find? Did we forget of all the fits and starts and reverses that evolution took that resulted in terrestrial plants on Earth? Lynn Margulis reminds us (1998) that if it wasn’t for symbiotic fungi, there wouldn’t be any bloody plants. Plants aren’t inevitable, aren’t a type with an essence of autotrophism.
OK so it’s inevitable that there might be many intelligent life forms out there even if they’re not human? Even the skeptic Shermer concedes to this; Dawkins tries to remind us that the size of the universe might make it so. I just think that there is a certain simplicity here that seems to neglect how we really might begin to be able to calculate such a probability. We are constantly reminded that we really can’t do such a thing, but then we leap to the assumption that will be in favor of plenty of aliens to populate our potentially real Star Trek universe. There’s just an eerie resemblance to the simplistic argument for intelligent design…something like, “Creation is so complex, it must have been designed supernaturally.” If we oversimplify we end up with argument like that. Even if we can’t really calculate such a thing, I’d like to clarify at least what we need to consider before we even make such assumptions.
Even if you expect from a very similar basic imput of pre-biotic chemicals, life may have a certain probability, we are still at level of our prokaryotes. The expectation that complex multicellular life, then even human life, has some sort of probabilistic inevitability needs to be analyzed more than just superficially and in the context of the history of evolutionary theory.
Stereoscopic vision and opposable thumbs were probably adaptations to an arboreal life. Bipedalism may have been adaptation for locomotion for such a tree-loving creature after its environment started changing from forest to savannah. The human mind might be the result of emergent properties of the existing nervous system of hominids that were coapted to exploit an ever changing and complicated social landscape. Did we obtain these things through a directed process that inevitably resulted in a primate and a genus like Homo? Or do environments mold organisms into reoccurring, recognizable shapes that makes it likely that aliens would be recognizable to us as humanoid or even just multicellular? Just how inevitable are all these transitions?
The answer might lie in what I would call Critical Contingency Factors (CCFs) in the natural history of our planet. CCFs inform us how we think about the historical and contingent nature of biological evolution, and might allow us to begin to give more respect to what kind of evidence we would need to even begin to speculate about the frequency of life, even intelligent life on other planets.
Symbiotic Theory and Coevoltution. Perhaps the strongest argument for contigency in evolution is Symbiosis, two or more organisms that create an association sometimes intimately and permanently. Lynn Sagan (Margolis) in her historic paper (1969) on symbiosis demonstrated that the speculations of scientists as early as the late 19th century ( e.g. Schimper, 1883) had foundation, namely that some eukaryotic cellular organelles started out as prokaryotes, which associated with other prokaryotes and early eukaryotes to form the first unicellular animal and plant cells. For plants their precursors, algae, had to symbiotically associate with cyanobacteria (became chloroplasts) in order to photosynthesize. Before that critical event this organism already had another symbiont, the purple bacteria (became mitochondria), which made it possible to produce much energy in an atmosphere that was becoming ever more oxygenated (2 billion yrs. BP). Margolis developed her theory of symbiogenesis over the course of the next twenty years before the consensus caught up with her. By the time she published Symbiotic Planet (1998), she had the advantage of providing many, many examples beyond mitochondria and plastids of symbiotic associations that affected speciation events, changed lineages, creating even new genera. The point is that all of these events are completely unpredictable and contingent. Even the first eukaryotes are the product of both strict Darwinian evolution and symbiogenesis. The caveat here is that once the symbionts established a permanent relationship, subsequent change required natural selection per Darwin as Ernst Mayr reminded us in the forward to Margolis’ book. As for coevolution many organisms have evolved to keep in step with, to outcompete, and have arms races with other organisms that may not even be in the same domain, kingdom, phylum, etc. There’s no predicting what future associations organisms may have that affect their subsequent evolution.
Catastrophism. There have been as many as five previous global mass extinctions of life, not to mention the inevitably more numerous regional cataclysms (Gould 2002). It was just such events that remind us of the contingent nature of our natural history, and the affect that such events might inevitably have on the course of the evolution that ultimately created the diversity of life on Earth that man has been given the privilege to witness over the last 200,000 years. There is no way to predict what the future evolutionary path of any taxon could be after such events. New habitats open up if a major clade goes extinct. Unoccupied niches mean the potential of new adaptive zones. It is often stated that there never would have been the Age of Mammals if it hadn’t been for the extinction of the dinosaurs, which the consensus of the scientific community is
Emergence. It has often been remarked that the sort of intelligent cognition that humans have may be an emergent property of the evolution of our nervous system. All throughout the history of evolution at different turning points that beget perhaps a new genus, family, order, or class, biological systems that operate far out of equilibrium (as in Kaufmann 1993) make a biological-organizational leap to a new state of equilibrium upon which natural selection can shape further. Such events may mark the genesis of new adaptive radiations. Other examples might include:
1. Hypercyles of RNA that learn to replicate at first with first fidelity and then selectively evolve until some cycles approach the edge of thermodynamic equilibrium until a final snap into place, which marks a new metabolic efficiency that also just happens to inadvertently include a cellular membrane…the origin of life.
2. Genetic regulation in single cell eukarotes that at first aggregate as individuals, then reorganize the sort of phenotypic expression that allows for a division of labor amongst colonies…the birth of multicellularity…achieved perhaps by the push or pull of duplicated genes that maintain the old phenotypic expression as well as affect ontogeny in different ways as they mutate.
3. Genetic regulation in small, allopatric populations that as inbreeding continues, a loosening of the genotype occurs such that new pleiotropic regulatory networks are formed…typical speciation events at the micro/macroevolutionary divide.
All these scenarios start at the point of already having prokaryotic life, except for CCF Emergence #1. There are numerous more CCFs that precede the evolution of the first cell. I won’t go into those here but is interesting to mention that we can bring into the argument the same factors that creationists discuss, scenarios in which the conditions that allowed life to exist in our universe are very improbable. “Old Earth” creationist Hugh Ross in his book The Creator and the Cosmos (2001) discusses the many factors that reduce the possibility of ET life: large planets close enough, but not so far away that act as cosmic vacuum cleaners (e.g. Jupiter and Saturn in our solar system), and reduce the likelihood of asteroid and comet impacts on potentially habitable planets; our one moon allows a relatively reasonable wobble to our planet’s rotation; a habitable planet is one that is in the sweet spot in its solar system; the solar system has to be in a sweet spot in its galaxy; and many other points. Ironic to use a creationist argument, n'est-ce pas?
Many milestones in the evolution of life may have been the result of contigent, emergent properties that lead to new levels of biological organization. None of these turning points in our natural history were inevitable or predictable. Multicellular life may be very, very rare in the universe. We must be wary of any attempts to argue that there are inevitable progressions in evolution or some essence that is humanoid that MUST naturally occur on this or any other planet. I may have out-skeptified Michael Shermer.
References
Gould, S. J. (2002). The Stucture of Evolutionary Theory. Belknap Press, Cambridge.
Kaufmann, S.A. (1993). The Origins of Order. Oxford University Press, Oxford.
Kiang, N.Y. (Apr. 2008). “The color of plants on other worlds.” Sci. Am.
Margolis, L. (1998). Symbiotic Planet. Basic Books, New York.
Mayr, E. (2001). What evolution is. Basic Books, New York.
Ross, Hugh (2001). Creator and the cosmos. Navpress, Baltimore.
Schimper AFW (1883). "Über die Entwicklung der Chlorophyllkörner und Farbkörper". Bot. Zeitung 41: 105–14, 121–31, 137–46, 153–62.
Sagan (Margolis), L. (1967). "On the origin of mitosing cells". J Theor Bio. 14 (3): 255–274
Shermer, M. (Nov. 2009). Will ET look like us? Sci. Am. p. 36.
Sunday, November 8, 2009
My Friend the Pastor
As an atheist my wife thinks I’m absolutely nuts when I listen to religious broadcasting on the radio. I’m pretty sure she’s not worried that I will convert; I once told her that after I’ve learned what I’ve learned and know what I know that if she sees me crossing myself before dinner that my mind is probably going. But I do listen to a couple of Christian radio stations that air out of Chicago. Originally I liked to listen the political opinions (seemingly homophobic rants in the guise of the protection of the institution of marriage, incredibly cynical and suspicious vitriol directed against candidate and later President Obama) and opinions on evolution, which unless these people are total idiots they must be knowingly distorting the record of 150 years of scientific research. As a biologist and a progressive, I am somewhat concerned what our religious brethren are up to. But on the evening drive home from work, I ran into the sort of Christian that defies stereotype casting.
Gregory Dickow is the pastor of Life Changers International Church based in Hoffman Estates, IL. He has a daily broadcast Ask the Pastor that airs in the early evening. I have listened to this radio call-in show for over a year, and have participated in the show by asking questions on subjects like evolution, different rewards in heaven for Christians with differing levels of good works, and other subjects. Mr. Dickow is always very cordial to me in spite of my handle, Chuck the Atheist. He should know that I don’t go around introducing myself as such, but thought that would be a good way for the Pastor to remember who I was. I’m by no means a vicious, spitting atheist of the Dawkins or Hitchens type (although I highly respect these individuals for other reasons). I think that evolutionists and atheists can have interesting and enlightening conversations without animosity. Gregory Dickow is one such Christian that does not make an atheist like me feel uncomfortable. I have to say that I am impressed by his more progressive stance that seeks to diminish the guilt that Christians might have about the normal contradictions in their lives in comparison to the ideal of a Christ-like existence. No sin is better or worse than an as Pastor Dickow relates, and the guilt that most Christians feel seemingly emanates more from other Christians who chastise them for their homosexuality or adultery while not seeing that their own vindictive, gossipy ways are just as much an affront to their god or religion.
Also interesting to me is that Gregory Dickow used to be a pastor with Maranatha Christian Ministries, which was a pretty fundamentalist Christian denomination from the 70’s and 80’s. This group was often the subject of suspicion from mainstream denominations and the press for its cohersive practices and close control over members dating lives and marriages. It wasn’t uncommon for ex-members to report that they were told implicitly or explicitly that their salvation was in jeopardy for leaving the church. MCM dissolved in the early 90’s. I have first-hand experience of this group from my early college years at SIU; I was a member of that church for a year and a half, and experienced some of the same things. I think that my path towards atheism was aided by my experience with Maranatha, although that was certainly not the only decisive factor. I suppose that makes me mildly suspicious of Gregory Dickow, but not overly so. I think he is a dynamic speaker, and has made a positive impact on his listeners. If anything he doesn’t seem horrified to speak with atheists or condemn anyone that doesn’t agree with him. A pretty interesting character. I wouldn’t mind writing a book with him, something along the lines of what questions atheists might have answered by the Pastor. Could be an interesting project.
Gregory Dickow is the pastor of Life Changers International Church based in Hoffman Estates, IL. He has a daily broadcast Ask the Pastor that airs in the early evening. I have listened to this radio call-in show for over a year, and have participated in the show by asking questions on subjects like evolution, different rewards in heaven for Christians with differing levels of good works, and other subjects. Mr. Dickow is always very cordial to me in spite of my handle, Chuck the Atheist. He should know that I don’t go around introducing myself as such, but thought that would be a good way for the Pastor to remember who I was. I’m by no means a vicious, spitting atheist of the Dawkins or Hitchens type (although I highly respect these individuals for other reasons). I think that evolutionists and atheists can have interesting and enlightening conversations without animosity. Gregory Dickow is one such Christian that does not make an atheist like me feel uncomfortable. I have to say that I am impressed by his more progressive stance that seeks to diminish the guilt that Christians might have about the normal contradictions in their lives in comparison to the ideal of a Christ-like existence. No sin is better or worse than an as Pastor Dickow relates, and the guilt that most Christians feel seemingly emanates more from other Christians who chastise them for their homosexuality or adultery while not seeing that their own vindictive, gossipy ways are just as much an affront to their god or religion.
Also interesting to me is that Gregory Dickow used to be a pastor with Maranatha Christian Ministries, which was a pretty fundamentalist Christian denomination from the 70’s and 80’s. This group was often the subject of suspicion from mainstream denominations and the press for its cohersive practices and close control over members dating lives and marriages. It wasn’t uncommon for ex-members to report that they were told implicitly or explicitly that their salvation was in jeopardy for leaving the church. MCM dissolved in the early 90’s. I have first-hand experience of this group from my early college years at SIU; I was a member of that church for a year and a half, and experienced some of the same things. I think that my path towards atheism was aided by my experience with Maranatha, although that was certainly not the only decisive factor. I suppose that makes me mildly suspicious of Gregory Dickow, but not overly so. I think he is a dynamic speaker, and has made a positive impact on his listeners. If anything he doesn’t seem horrified to speak with atheists or condemn anyone that doesn’t agree with him. A pretty interesting character. I wouldn’t mind writing a book with him, something along the lines of what questions atheists might have answered by the Pastor. Could be an interesting project.
Was Darwin a Creationist?
Was Darwin a creationist? A simple answer is that at the vast majority of those in the 19th century concerned with describing the natural world prior to the development of evolutionary theory were implicitly or explicitly creationists. After finding medical school quite distasteful, even Darwin contemplated joining the ranks of the clergy. For someone of the social status that the Darwins enjoyed, becoming a vicar was a profession that was befitting his social rank. But it would have also afforded him with the time to be a naturalist. In fact most naturalists were at the time clergymen. There was no biology then, there was only Natural Theology. Natural theologians attempted to define and characterize nature as a result of divine creation. Before Darwin solidified his career goals, he went on a six year circumnavigation of the globe on the HMS. He collected many specimens of plants and animals that he sent to academics back in England. It wasn’t until after Darwin returned from his voyage in 1836 that he began to develop a theory that attempted to explain the distribution of species that he found along his travels. But Darwin was never a foe of religion. His wife Emma Wedgewood (of the Wedgewood pottery fame) was deeply religious. Darwin quietly developed the theory of evolution with an incredible sensitivity to what implication his ideas might have even in his own home. Darwin never proclaimed himself to be an atheist, but simply developed a theory that attempted to explain the history of life based upon natural causes. He saw that the distribution of species that he found on his voyage and those described by his contemporaries were best explained by the Transmutation of species, one of the theoretical components of evolutionary theory. Species were thought to be fixed creations at the time, but Darwin eventually realized that one species gave rise to the next. He saw that the diversity of life could be explained by speciation events. Personally he probably thought of himself as an agnostic that had no need of supernatural explanations to explain natural history.
Thursday, November 5, 2009
Personal Note: Autobiography
My primary intention for this blog is the discussion of biological evolutionary literature and bio info on Charles Darwin. After the opening salvo along those lines, I thought it might be fun also to institute entries that will be called Personal Notes from time to time. I understand that although some might find the discussions on evolution interesting, comprehensive treatment of the subject may get a little dry for some readers. I have no real intention of dumbing down these discussions or making them funny or cute, so an interjection from time to time off subject may be just the thing. So here's a little of my autobiographical information.
I'm a microbiologist that works in the food industry. I'm involved mostly with research on the natural preservation of foods. Like Egon from Ghostbusters, I collect "spores, molds, and fungus." Over a several year period, I have collected many specimens of bacteria and fungi that have spoiled food such that I have microbial guinea pigs upon which I can test ideas. I've been in the consumer products industry for over 20 years. Growing up and in college I had two careers in mind that I thought I might end up pursuing, biology and anthropology. I liked reading and studying about human culture, but I really gravitated towards the rest of the living world that I find vastly more interesting and often a lot less ugly. I was an evangelical christian for a brief period of time, but realized rather quickly that this stifled my curiosity and zest for life. Now many years later, I would have to characterize myself as an atheist. Better yet I think I would have to say that I really don't put stock in belief itself. I feel that to believe is accept something out of hope, fear, and guilt, all of which seems to take me away from reality and the reality of the moment. We are here now; that's all. Some of these sentiments I got from Buddhism, but in my pursuit of eastern philosophical traditions, I came to the realization that I was just projecting my inner concerns again and simply looking for another religion. So really belief is an outmoded way of just projecting inner turmoil. There is a saying that if you meet the Buddha, you should kill him. The thing that you think you see may be wonderful, make you feel good, fashionable, but it's just a construct. Beliefs are completely unnecessary. You might be able to manufacture your own truths, but reality doesn't give a damn about what you think, what you want, what you think you want.
Oh, I suppose I forgot the part about being married to a really wonderful person, and having two really smart and funny kids. My kids take voice and acting lessons at a local community theater. The whole family gets involved. My son and I have worked on a props crew, my daughter and I on a paint crew, my wife has made costumes. I've done set construction for three shows. My son recently got cast in his first play; he is very excited. It's a really cool diversion. I never took drama classes or anything when younger, but I now find theater really fun and interesting. I also like hiking in the woods, raising and training dogs, and of course non-fiction science writing. I have in the past written some short stories. I enjoy fiction, but not don't think that it has a lot of staying power for me. OK that's quite enough. Going on and on about myself makes me feel a little uncomfortable.
I'm a microbiologist that works in the food industry. I'm involved mostly with research on the natural preservation of foods. Like Egon from Ghostbusters, I collect "spores, molds, and fungus." Over a several year period, I have collected many specimens of bacteria and fungi that have spoiled food such that I have microbial guinea pigs upon which I can test ideas. I've been in the consumer products industry for over 20 years. Growing up and in college I had two careers in mind that I thought I might end up pursuing, biology and anthropology. I liked reading and studying about human culture, but I really gravitated towards the rest of the living world that I find vastly more interesting and often a lot less ugly. I was an evangelical christian for a brief period of time, but realized rather quickly that this stifled my curiosity and zest for life. Now many years later, I would have to characterize myself as an atheist. Better yet I think I would have to say that I really don't put stock in belief itself. I feel that to believe is accept something out of hope, fear, and guilt, all of which seems to take me away from reality and the reality of the moment. We are here now; that's all. Some of these sentiments I got from Buddhism, but in my pursuit of eastern philosophical traditions, I came to the realization that I was just projecting my inner concerns again and simply looking for another religion. So really belief is an outmoded way of just projecting inner turmoil. There is a saying that if you meet the Buddha, you should kill him. The thing that you think you see may be wonderful, make you feel good, fashionable, but it's just a construct. Beliefs are completely unnecessary. You might be able to manufacture your own truths, but reality doesn't give a damn about what you think, what you want, what you think you want.
Oh, I suppose I forgot the part about being married to a really wonderful person, and having two really smart and funny kids. My kids take voice and acting lessons at a local community theater. The whole family gets involved. My son and I have worked on a props crew, my daughter and I on a paint crew, my wife has made costumes. I've done set construction for three shows. My son recently got cast in his first play; he is very excited. It's a really cool diversion. I never took drama classes or anything when younger, but I now find theater really fun and interesting. I also like hiking in the woods, raising and training dogs, and of course non-fiction science writing. I have in the past written some short stories. I enjoy fiction, but not don't think that it has a lot of staying power for me. OK that's quite enough. Going on and on about myself makes me feel a little uncomfortable.
Tuesday, November 3, 2009
More to Evolution than Natural Selection?
Is there really more to evolution than natural selection? There’s no denying that natural selection, acting at the organismic or individual level, probably explains most phylogenetic change. I have to do a little more studying on neutral theory starting with Sewall Wright, then Kimura’s neutral theory of genetic change, and genetic drift to really give a fair treatment of these theories so I won’t address them yet. I’ll leave that for another day except to say that I’m a little suspicious of mechanisms that are claimed not to significantly influence phenotypic change (on which selection obviously acts), yet are touted as important refinements to evolutionary theory.
I thought it might be more interesting initially to talk about a couple of theories or concepts of change that may have played part in evolutionary history, but might really be outside of traditional Darwinism. The first is symbiotic theory advanced by Lynn Margulis (more recently in her book, Symbiotic Planet) and others. It may not be known widely in the general public that perhaps one of the most significant events in evolution (at its barest definition, that of change, or more synonymous with natural history) was the incorporation of bacteria into early eukaryotic cells. Mitochondria are apparently vestiges of a symbiotic association of ancient eukaryotic cells with bacteria. It would be difficult to explain such an event as a result of genetic variation and selection. It may have been the result of a long association of organisms in a common ecosystem, but without this contingent happening multicellularity may have not evolved. For the bacteria once incorporated into cells as mitochondria allowed early eukaryotes to take advantage of an environment that was becoming increasingly oxygenated (around two billion years ago). Another significant symbiotic association was that of cyanobacteria and eukaryotes that gave rise to algae; the result was the chloroplast and a way of generating energy from sunlight.
Other perhaps significant agents of change are the concepts of emergence and self-organization. Stuart Kaufmann (in his book Origin of Order and earlier writings) proposed that stabilization of organic systems that fluctuate outside of equilibrium may and probably have produced new organizational states that result in the emergence of new properties that provide the new construct (organism) with a selective advantage. A simplistic example may be the rise of multicellular organisms. Before multicellularity, the biological world was microscopic. Early on this probably was the results of natural selection: the consequence of genetic variation that led to the ability of cells to associate intimately and become tightly integrated colonies of cells that are successful. But once such an organizational change took place, larger organisms could evolve that would have the selective advantage of being bigger and being able to exploit new resources at this higher level of biological organization. I’d like to conclude with the caveat that Ernst Mayr gave in the introduction of Margulis’ Symbiotic Planet, namely that whatever the source of change that was produced by symbiosis (and we could add here emergence), well weathered natural selection would afterward take over and be the primary source of diversification after emergent characteristics or symbiotic associations had arisen in these lineages.
I thought it might be more interesting initially to talk about a couple of theories or concepts of change that may have played part in evolutionary history, but might really be outside of traditional Darwinism. The first is symbiotic theory advanced by Lynn Margulis (more recently in her book, Symbiotic Planet) and others. It may not be known widely in the general public that perhaps one of the most significant events in evolution (at its barest definition, that of change, or more synonymous with natural history) was the incorporation of bacteria into early eukaryotic cells. Mitochondria are apparently vestiges of a symbiotic association of ancient eukaryotic cells with bacteria. It would be difficult to explain such an event as a result of genetic variation and selection. It may have been the result of a long association of organisms in a common ecosystem, but without this contingent happening multicellularity may have not evolved. For the bacteria once incorporated into cells as mitochondria allowed early eukaryotes to take advantage of an environment that was becoming increasingly oxygenated (around two billion years ago). Another significant symbiotic association was that of cyanobacteria and eukaryotes that gave rise to algae; the result was the chloroplast and a way of generating energy from sunlight.
Other perhaps significant agents of change are the concepts of emergence and self-organization. Stuart Kaufmann (in his book Origin of Order and earlier writings) proposed that stabilization of organic systems that fluctuate outside of equilibrium may and probably have produced new organizational states that result in the emergence of new properties that provide the new construct (organism) with a selective advantage. A simplistic example may be the rise of multicellular organisms. Before multicellularity, the biological world was microscopic. Early on this probably was the results of natural selection: the consequence of genetic variation that led to the ability of cells to associate intimately and become tightly integrated colonies of cells that are successful. But once such an organizational change took place, larger organisms could evolve that would have the selective advantage of being bigger and being able to exploit new resources at this higher level of biological organization. I’d like to conclude with the caveat that Ernst Mayr gave in the introduction of Margulis’ Symbiotic Planet, namely that whatever the source of change that was produced by symbiosis (and we could add here emergence), well weathered natural selection would afterward take over and be the primary source of diversification after emergent characteristics or symbiotic associations had arisen in these lineages.
Monday, November 2, 2009
What is Neo-Darwinism?
After publication of On the Origin of Species, the fact of organic evolution began to be accepted in the scientific community. But only certain elements of Darwin's thesis gained anything like a wide acceptance for the rest of the 19th and early part of the 20th century. Transmutation (speciation) and the decent of all organisms from a common ancestor were more or less accepted, but perhaps the primary mechanism of evolution, natural selection, was not necessarily thought to be a main factor in evolution as well as the gradualistic nature of evolution that Darwin envisioned. Darwin, however, did not understand the nature of genetic material or the source of the variation on which selection acts. After the turn of the 20th century, Mendel's research was rediscovered after being virtually ignored for close to fifty years. Mendel showed through experiments with pea plants how traits were passed from one generation to the next. Early geneticists and embryologists began to explain how variation in eukaryotic organisms can arise and affect phenotypic expression. Ernst Mayr, G. G. Simpson and others towards the mid-20th century recognized that a new synthesis should be made between Mendelian genetics and theory of natural selection to which Darwin adhered. This became to be known as the Modern Synthesis or Neo-Darwinism. Over the last six decades no theoretical challenge to the Modern Synthesis has gained a wide consensus.
Sunday, November 1, 2009
Conception
My interest in evolutionary biology began with a subscription of Natural History several years ago. I was captivated by the late Stephen Jay Gould's column, which motivated me to start a careful study of first the popular literature, and more recently the professional. I would like to start a forum for discussion of concepts and ideas that evolution encompasses. There really is "a grandeur to this view of life." (Darwin, On the Origin of Species). I open this blog to anyone who would like to comment on the posts, and thereby be part of this enterprise. I am very excited to share with you my thoughts and impressions of perhaps the greatest subject that science has to offer. Welcome all.
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