Evolutionary Catechism

Under 'Evolutionary theory beyond Darwin', David has drawn our attention to an article by Barry Arrington, an ID-er, castigating Darwinists for imposing their theory on the facts ... in this case, filling the gaps in the fossil record with their hypotheses. George has directed us towards two Darwinist responses.-I find it a bit rich that an ID-er should attack Darwinists for promoting their agenda while he tries to promote his own, but of course that doesn't in itself invalidate the argument. I do wish, though, that both sides would approach the theory of evolution scientifically, i.e. without any agenda, and I do wish everyone would recognize that it isn't just one idea but a combination of several ideas. It might therefore be interesting to take the different components separately and see where all of us stand. Here are a few relevant questions. -1) Do I believe that all life is descended from one form (or a few forms)?
(If so, there must be a line from those early forms to all species, including ourselves.)
2) If the answer to 1) is yes, do I believe that the line from early forms to ourselves has been gradual and continuous, or a "punctuated equilibrium"?
3) Do I believe that all complex organs have come into existence through random 
mutations followed by successive modifications?
4) Do I believe that organisms can be changed by their environment?
5) Do I believe that natural selection results in the preservation and improvement of advantageous characteristics?
6) Do I believe that natural selection gives rise to new species? 
7) Do I believe that the gaps in the fossil record are caused by "the extreme imperfection of the geological record" (Darwin) or by imperfections in Darwin's theory?-Answers, comments and additional questions would be most welcome.

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dhw,-A few observations before I get to the meat:-Who is it really, that is engaging in an agenda push? If David is right and (60%) of life-scientists are religous believers of some sort--then why is ID such a castigated philosophy among scientists at large? Peer pressure doesn't work as an explanation if greater than 50% of scientists support some kind of theism. Look at American politics, where the religious right control only 30% of the population at large, yet are so predominant in American politics that you can't go one day without hearing from them. Either 60% of life scientists are enormously quiet--or there's something wrong with ID in America. -MEAT:-1) Do I believe that all life is descended from one form (or a few forms)?
(If so, there must be a line from those early forms to all species, including ourselves.)-This is difficult for me: I think that the chemistry behind life stands reason to be very ubiquitous, so I think possibilities exist where life appeared in multiple places at once, and of course, it's possible that life occurred once and all things descended from one organism. I know all life has DNA, and I accept whatever implications that has. 

2) If the answer to 1) is yes, do I believe that the line from early forms to ourselves has been gradual and continuous, or a "punctuated equilibrium"?-Belief for me here is irrelevant; this is an area of contention within modern biology. In either case, changes in organisms are only passed on by reproduction alone making it very difficult to argue that punctuated equilibrium isn't simply a ramping up of the pace of natural selection over time. 

3) Do I believe that all complex organs have come into existence through random
mutations followed by successive modifications?-Most biologists here would ask, "What's the difference?"-4) Do I believe that organisms can be changed by their environment?-This is tricky, do you mean to ask whether or not organisms respond to change, or that something in the environment forces them to change? It's subtle but there's a difference. If it's the former, there is clear evidence of this. If its the latter, than how would we differentiate it from the former? -5) Do I believe that natural selection results in the preservation and improvement of advantageous characteristics?-I have seen nothing that refutes this. -6) Do I believe that natural selection gives rise to new species?-Whatever the driver behind change; epigenetics, etc, there is no way to refute the role natural selection would still play. It would still explain how *many* species came to be. -7) Do I believe that the gaps in the fossil record are caused by "the extreme imperfection of the geological record" (Darwin) or by imperfections in Darwin's theory?-I think the former stands more to reason; natural selection is used actively by scientists conducting all sorts of experiments. An argument based on the fossil record alone is weak simply because of the chances of intact fossils being recovered; though Darwin's theory was based on the fossil record, the modern uses of natural selection far outstrip the evidence for evolution based on the fossil record. In short, Watson and Crick have done more to verify natural selection than Darwin.

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\"Why is it, Master, that ascetics fight with ascetics?\"

\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"

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> 1) Do I believe that all life is descended from one form (or a few forms)?
> (If so, there must be a line from those early forms to all species, including ourselves.)-A few forms. I believe in convergence (Conway Morris)
>
> 2) If the answer to 1) is yes, do I believe that the line from early forms to ourselves has been gradual and continuous, or a "punctuated equilibrium"?-Punctuated equilibrium. that is what the fossil record says.
> 
>3) Do I believe that all complex organs have come into existence through random
 mutations followed by successive modifications?-Mutations play a role, but the major organs are developed following a pre-arranged plan in DNA-
> 
> 4) Do I believe that organisms can be changed by their environment?-No question. Yes->
> 5) Do I believe that natural selection results in the preservation and improvement of advantageous characteristics? -Yes
>
> 6) Do I believe that natural selection gives rise to new species? -No. Only variations in existing species.-
>
> 7) Do I believe that the gaps in the fossil record are caused by "the extreme imperfection of the geological record" (Darwin) or by imperfections in Darwin's theory? -Yes, there are large gaps. Darwin's theory does not create gaps, as a question seems to imply. What Darwinists do is create just-so stories to fill the gaps by their theory. Gaps are an unknown territory and should be left vacuous until intermediate forms are discovered, if they exist at all. We still have puctuated equilibrium and saltation to rely on.

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Responses to your catechism, but please bear in mind that I'm not a biologist, just someone with a interest in the subject:-1) Do I believe that all life is descended from one form (or a few forms)?
(If so, there must be a line from those early forms to all species, including ourselves.)-It may depend how you distinguish one "form" from another. For instance, the earliest replicating molecules may have formed a system of related structures that reproduce each other cyclically. Also there is not a single line but a branching tree.-2) If the answer to 1) is yes, do I believe that the line from early forms to ourselves has been gradual and continuous, or a "punctuated equilibrium"?-This may depend on how close you look, i.e. what magnification you use. Since everything is made from atoms, which are discrete objects, strictly continuous evolution in the mathemartical sense of continuity is impossible. But generally changes to an organism will be very minor. I can't see how big changes can occur by natural processes. -3) Do I believe that all complex organs have come into existence through random 
mutations followed by successive modifications?-Random variation followed by natural selection. There may be many different ways in which variations occur, not necessarily mutation caused by radiation. -4) Do I believe that organisms can be changed by their environment?-Populations of organisms with variation may be subject to environmental changes that are advantageous to part of the population but deleterious to others, thus resulting in the next generation having a different distribution of variations, and over many generations this can result in a change of significant magnitude.-5) Do I believe that natural selection results in the preservation and improvement of advantageous characteristics?-The characteristics need not be advantageous in any absolute sense, only in relation to the circumstances. For example loss of sight in cave dwellers. Or loss of brain in inactive creatures.-6) Do I believe that natural selection gives rise to new species? -Over a considerable time period, subject to environmental changes.-7) Do I believe that the gaps in the fossil record are caused by "the extreme imperfection of the geological record" (Darwin) or by imperfections in Darwin's theory?-We are lucky to have any fossils at all, in view of the special conditions necessary for dead bodies to be preserved in this way.

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GPJ

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There was a good Horizon programme on TV this evening about viruses.
http://www.bbc.co.uk/programmes/b00q2rdj-It mentioned the work of Eckard Wimmer who synthesised a virus.
This was back in 2002.
http://news.bbc.co.uk/1/hi/2122619.stm-It also featured a scientist who has located viruses in archaea in hot springs at Yellowstone Park, and who thinks viruses may have preceded the evolution of bacteria and other forms of life.
http://www.spaceref.com/news/viewpr.html?pid=14215-
On facebook one of my Friends posted this link:
Should Evolutionary Theory Evolve?-http://www.the-scientist.com/2010/1/1/24/1/-This is about the Altenberg conference.-Quote: City University of New York evolutionary biologist and philosopher Massimo Pigliucci insists that expanding evolutionary theory so that it captures recent insights doesn't mean throwing out 150 years of sound thinking. "We're not talking a revolution," he says. "Nobody's going to deny Darwin and all that stuff. But it has been several decades since the last time evolutionary biologists actually sat around the table, so to speak, and came up with the basic principles of their field." -Quote: There's no need to formally revisit the Modern Synthesis, argues Douglas Futuyma, an evolutionary biologist at the State University of New York at Stony Brook, because evolutionary theory is flexible enough to incorporate well-substantiated new ideas as they arise. "I think the evolutionary synthesis has already been extending itself almost continually for the last few decades," he says. "I'm not saying that there's nothing interesting [in the Extended Synthesis]. I just think the self-conscious labeling of it as a new point of view or a challenge to the old, most people don't buy."

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GPJ

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My thanks to Matt, George and David for three sets of rather different answers to my list of questions. It goes without saying that none of us subscribe to Creationism, but how evolution moves from early forms of life to its present complexities remains a wide open subject. -This is reinforced by a thought-provoking article on the subject ... for which again my thanks to George. He quotes Massimo Pigliucci, who says: "Nobody's going to deny Darwin and all that stuff." But which aspects of Darwin is nobody going to deny? The gradualness of evolution ("Natura non facit saltum", says Darwin), innovation through random mutations and slow modifications, natural selection resulting in new species (as opposed to variations in existing species), absence of intermediate forms due to the imperfection of the geological record?-I think we all accept evolution in some form, but the devil is in the detail, and evolutionary biologists themselves can't agree on that. -Douglas Futuyma says there's "no need to formally revisit the Modern Synthesis". Andreas Wagner says: "If you're interested in evolutionary innovation, you can't get away anymore with a very simple, one-dimensional notion of a phenotype. Now we can recognize that there is a deficiency in the Modern Synthesis."-Here's another stimulating quote: "Genotypes were assumed to translate more or less directly into phenotypes, and evolutionary change stemmed from the slow, gradual accumulation of random genetic mutations. But with the rise of the EvoDevo field [...] this simplified picture is becoming more complex."-Epigenesis also comes under scrutiny:
Vincent Colet: "Epigenetic inheritance is widespread, but that doesn't mean it lasts and causes evolutionarily meaningful effects."
Jerry Coyne: "Usually epigenetic characters aren't inherited past one or two generations."-The more complex the process (and the more disagreements there are among the experts), the more difficult it becomes to justify agendas. -One very useful term also emerges from the article. In my discussions with George, I've repeatedly argued that in addition to being able to replicate, the first forms of life must have had the potential ability to change ... otherwise there could have been no evolution. Now to my delight I find there is an official scientific word for it: EVOLVABILITY.

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> Douglas Futuyma says there's "no need to formally revisit the Modern Synthesis". Andreas Wagner says: "If you're interested in evolutionary innovation, you can't get away anymore with a very simple, one-dimensional notion of a phenotype. Now we can recognize that there is a deficiency in the Modern Synthesis."
> 
> Here's another stimulating quote: "Genotypes were assumed to translate more or less directly into phenotypes, and evolutionary change stemmed from the slow, gradual accumulation of random genetic mutations. But with the rise of the EvoDevo field [...] this simplified picture is becoming more complex."
> 
> Epigenesis also comes under scrutiny:
> Vincent Colet: "Epigenetic inheritance is widespread, but that doesn't mean it lasts and causes evolutionarily meaningful effects."
> Jerry Coyne: "Usually epigenetic characters aren't inherited past one or two generations."
> 
> The more complex the process (and the more disagreements there are among the experts), the more difficult it becomes to justify agendas. 
> 
> One very useful term also emerges from the article. In my discussions with George, I've repeatedly argued that in addition to being able to replicate, the first forms of life must have had the potential ability to change ... otherwise there could have been no evolution. Now to my delight I find there is an official scientific word for it: EVOLVABILITY.-Larry Moran's blog Sandwalk on 2/15/11 has a fascinating discussion of Evodevo describing the advent of HOX genes, new genes and control genes in the development of differing forms that are no way homologous. The discussion does not account for these jumps in evolution, and still support Gould's punctuation theory.-http://sandwalk.blogspot.com/

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One very useful term also emerges from the article. In my discussions with George, I've repeatedly argued that in addition to being able to replicate, the first forms of life must have had the potential ability to change ... otherwise there could have been no evolution. Now to my delight I find there is an official scientific word for it: EVOLVABILITY.-
Here is another example of Evodevo: Eye spots in mollusks. The embryos migrate toward light, and light related chemicals are present. Eye convergence at an ancient time? Pre-planning? Be sure to listen to the research scientist and skim his paper. Looks like evolvability to me, set up well in advance.- http://blog.the-scientist.com/2011/03/31/yale-passamaneck-and-eye-evolution/

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Evolutionary Catechism (Evolution)