Tuesday, August 16, 2005

Harvard to Investigate Origins of Life, etc

Here are news items with my comments in square brackets:
Harvard to Investigate Origins of Life, ABCNEWS/ Associated Press Aug. 16, 2005 - Harvard University is joining the long-running debate over the theory of evolution by launching a research project to study how life began. The team of researchers will receive $1 million in funding annually from Harvard over the next few years. The project begins with an admission that some mysteries about life's origins cannot be explained. "My expectation is that we will be able to reduce this to a very simple series of logical events that could have taken place with no divine intervention," said David R. Liu, a professor of chemistry and chemical biology at Harvard. The "Origins of Life in the Universe Initiative" is still in its early stages, scientists told the Boston Sunday Globe. Harvard has told the research team to make plans for adding faculty members and a collection of multimillion-dollar facilities. Evolution is a fundamental scientific theory that species evolved over millions of years. It has been standard in most public school science texts for decades but recently re-emerged in the spotlight as communities and some states debated whether school children should also be taught about creationism or intelligent design. The theory of intelligent design says life on earth is too complex to have developed through evolution, implying that a higher power must have had a hand in creation. Harvard has not been seen as a leader in origins of life research, but the university's vast resources could change that perception. "It is quite gratifying to see Harvard is going for a solution to a problem that will be remembered 100 years from now," said Steven Benner, a University of Florida scientist who is one of the world's top chemists in origins-of-life research. ... [The references to "the long-running debate over the theory of evolution … whether school children should also be taught about creationism or intelligent design," "intelligent design says life on earth is too complex to have developed through evolution" and "with no divine intervention" is a dead give-away that Harvard (which up till now has shown little or no interest in origin of life research) is reacting to the rising tide of scepticism about evolution. As Phil Johnson observed, "If Darwinists are to keep the Creator out of the picture, they have to provide a naturalistic explanation for the origin of life." (Johnson P.E., "Darwin on Trial," 1993, p.103). Antony Flew's abandoning of atheism for deism because, "It has become inordinately difficult even to begin to think about constructing a naturalistic theory of the evolution of that first reproducing organism" (Philosophy Now) would not have gone unnoticed among the Harvard secular elite. It is also a tacit admission that, more than a half-century since the Miller-Urey experiment (1953), materialistic-naturalistic science has no explanation of the origin of life. Note that the proposition there was "no divine intervention" in the origin of life is "science", and so can be taught in schools, but the counter-proposition that there was divine intervention" is dismissed as "religion" and so cannot be taught in schools!]
Study: Most Wild Chimps Are Southpaws, ABCNEWS/ Associated Press … RANDOLPH E. SCHMID AP Science Writer The Associated Press Aug. 16, 2005 - When it comes to fishing tasty termites out of their mounds, wild chimpanzees don't have the right stuff. Most, in fact, are southpaws. A three-year study of 17 wild chimps in Gombe National Park, Tanzania, found that 12 of them used their left hands when using sticks to probe for termites. Four were right-handed and one was listed as ambiguously handed. "Contrary to previous claims, wild chimpanzees show population-level handedness in tool-use," reported the research team led by William D. Hopkins of the Yerkes National Primate Research Center at Emory University in Atlanta. Population-level handedness indicates a preference for one hand in a large group. Hopkins' findings are reported in Tuesday's issue of Proceedings of the National Academy of Sciences. The paper also looked at previous studies of chimpanzees and found that others had noted a left-handed preference when using sticks to fish for termites, but there had been reports of a right-handed preference when cracking nuts. Scientists have long debated whether nonhuman primates exhibit handedness. Because the hands are controlled by opposite sides of the brain, the finding could indicate that this brain division had begun as long as 5 million years ago, prior to the split between humans and chimpanzees. Richard W. Byrne of the University of St. Andrews in Fife, United Kingdom, who has reported on hand-preference in mountain gorillas doing complex tasks, said: "It now looks as if whatever gives a population skew to manually skilled behavior has its roots deep in the shared ancestry of humans and all other African great apes." ... A larger question concerns the evolution of language, Hopkins said in a telephone interview. Most people, right and left handed, use the left hemisphere of the brain to process language, he explained. The argument has been made that if humans developed language after the split from apes, and language is related to handedness, then there shouldn't be handedness in apes, he said, "This reinforces the view that the whole historical link between language and handedness is probably not a correct one and people need to rethink those ideas," Hopkins said. ...
Study: Chimps show hand preference, CNN, August 16, 2005 … Chimpanzees in captivity show a right-handed preference for some tasks, but researchers have wondered if this because they are raised by humans, who are mostly right-handed. ... Humans are still far more likely than chimps to be right-handed. It could be there was a genetic mutation favoring right-handedness in humans, the researchers said. Or it could be that this is a reflection of the unique organization of human brains, they added.
[If chimps were predominantly right-handed like humans, it would be hailed as evidence of our close relationship. Therefore, the opposite handedness in chimps from humans is evidence of a more distant relationship. This also indicates that the language ability in humans arose after the chimp-human split. This reminded me of what Gould pointed out about the differences between humans and chimps:
"The genetic differences between humans and chimps are minor, but they include at least ten large inversions and translocations. An inversion is, literally, the turning around of a chromosomal segment. Each hybrid cell would have a set of chimp and a corresponding set of human chromosomes. Egg and sperm cells are made by a process called meiosis, or reduction division. In meiosis, each chromosome must pair (lie side by side) with its counterpart before cell division, so that corresponding genes can match up one to one: that is, each chimp chromosome must pair with its human counterpart. But if a piece of human chromosome is inverted relative to its counterpart in chimps, then gene-by-gene pairing cannot occur without elaborate looping and twisting that usually precludes successful cell division." (Gould S.J., "Ever Since Darwin: Reflections in Natural History," [1978], Penguin: London, 1991, reprint, p.55)
Each of those "ten large inversions and translocations" would presumably mean a new species (for the "meiosis" reason that Gould gave), so while I accept that humans and chimps share a common ancestor, there are probably at least ten species in between them and us.]
Cloning a world away, Roger Highfield, Daily Telegraph, 10 August 2005. ... In the light of cloned mice, goats, horses, pigs, deer, carp and fruit flies, the creation of Snuppy by South Korea's king of cloning, Prof Wook-Suk Hwang, shows that there is no fundamental reason why humans cannot be cloned, though experiments to date underline how risky and inefficient the process is. ... Early cloning attempts relied on sea urchins, salamanders, frogs and other creatures which have big eggs that are conveniently delivered as spawn. These cold-blooded pioneers were used to explore the biology of development to shed light on whether creatures were fully formed at the moment of fertilisation, and just grew, or if they developed from a single cell to the complex arrangement of billions in an adult. Nuclear transfer was first used almost a century ago by the great German embryologist Hans Spemann, who used a delicate hair from Margrette, his baby daughter, as a noose to manipulate a newly fertilised salamander egg. ... Evidence that all of the cells of an adult contained the recipe to make an individual was obtained in the 1950s by John Gurdon at Oxford University, who was trying to clone the African clawed frog Xenopus laevis. He went on to create 30 albino frogs, cloned by nuclear transfer from the cells of an albino tadpole into the eggs of normally pigmented frogs. One of his pupils, Chris Graham, wanted to develop nuclear transfer for mice and this marked the start of efforts to clone mammals that culminated in 1986 in the work of Steen Willadsen, an inventive Dane working in Cambridge. His lambs were the first mammals to be cloned beyond any doubt by nuclear transfer and his work would provide much of the impetus that drove Prof Ian Wilmut to create Dolly at the Roslin Institute, near Edinburgh. Over the years, Hollywood has invested millions in cloning fantasies. ... Copies of Adolf Hitler starred in the 1978 movie of another Ira Levin novel, The Boys From Brazil. ... Based on Prof Hwang's experience with Snuppy (although, admittedly, there are technical reasons why dogs are hard to clone) to ... clone a baby would mean obtaining more than 1,000 fresh human eggs, which are in very short supply, and using them to create 1,000 cloned embryos. If the Snuppy example holds true, these would then be implanted in 123 women. Of those surrogate mothers, all but one would risk the hurt and turmoil of the pregnancy failing, of miscarriages and deformed foetuses. Another common problem with nuclear transfer is unusually big offspring. Prof Wilmut also fears the psychological effects on a clone. In short, despite Hollywood's efforts to make it look easy, even a totalitarian dictator would find it tough to indulge a narcissistic cloning fantasy. ... [I did a major assignment on cloning in a molecular biology unit 3-4 years ago, and my conclusion then was that humans, who are particularly difficult to clone, apart from the ethical, social, economic and legal reasons (a cloned human, unlike a dog, could sue its creators), would never be cloned. It is nice to see this now being increasingly acknowledged. Indeed, so many are the problems of cloning, it is unlikely that even the original idea of cloning identical lines of high-quality farm animals (to replace the hit and miss of selective breeding) is an economic proposition.]
Did double whammy of volcano and asteroid wipe out dinosaurs?, Steve Connor, The Independent 17 August 2005 ... 16 August 2005 Volcanic eruptions may have triggered the demise of the dinosaurs. Many scientists believed that an asteroid caused the mass extinction 65 million years ago. However, a new study points to a more complex event that began with a series of eruptions which took place in what is now north-western India. The Deccan Traps in Maharashtra state are flows of lava resulting from huge outpourings of molten rock and ash. A mile deep, they cover about 200,000 square miles. Vulcanologists have long thought the eruption, dated to about 65 million years ago, could have caused the extinction. However, the Deccan Traps resulted from a series of eruptions that occurred over perhaps a million years. This would have given the global climate plenty of time to adjust. But the study shows a major part of the eruption occurred over a short period. Scientists from the Institut de Physique du Globe de Paris calculated that at least 2,000ft of lava was deposited in 30,000 years, which could have greatly altered global climate. They have also shown that the Traps were erupting when the asteroid crashed into what is now Mexico. This was a spectacular and almost unprecedented double whammy for Earth. Mike Widdowson, a vulcanologist, said it seems the end of the dinosaurs may have begun with climate change brought about by the eruptions and ended with the asteroid. "The eruptions pre-conditioned the global environment toward a catastrophic tipping point before the impact occurred. The asteroid was the coup de grĂ¢ce," he said. ... [Another article on this that makes it clearer that the K/T mass extinction that took out the dinosaurs was an "almost unprecedented double whammy for Earth", in a short period of global warming caused by the greenhouse effect of volcanic emissions, then a sudden period of global cooling by the asteroid impact's `nuclear winter'. Since without this `one-two punch' we would not be here, I regard this as another fine-tuned event by an Intelligent Designer (who I assume is the Christian God), in preparing the Earth for man. I will add this also to section PC 8.3.1.1.1 "Preparing Earth for Life and Man ... Pruning the Tree of Life ... The Cretaceous-Tertiary (K/T) extinction " to the outline of my planned second book "Progressive Creation"]
Building a Virtual Microbe, Gene by Gene by Gene, Carl Zimmer The New York Times, August 16, 2005, Michael Ellison has a dream: to reconstruct a living thing inside a computer, down to every last molecule. It is, he said, "the ultimate goal in biology to be able to do this." It's a dream that Dr. Ellison, a biologist at the University of Alberta, shares with other scientists, who have imagined such an achievement for decades. Understanding how all of the parts of an organism work together would lift biology to a new level, they argue. Biologists would be able to understand life as deeply as engineers understand the bridges and airplanes that they build. "You can sit down at a computer, and you can design experiments, and you can see the performance of this thing, and then you can figure out why it's done what it's done," Dr. Ellison said. "You're not going to recognize the full return of the biological revolution until you can simulate a living organism." In the past few years this fantasy has become plausible and now Dr. Ellison is part of an international team of biologists who are now trying to make it a reality. They have chosen to recreate Escherichia coli, the humble resident of the human gut that has been the favorite species for biology experiments for decades. "We picked the simplest organism about which we know the most," Dr. Ellison said. Scientists may know more about E. coli than they do about any other species on earth, but that doesn't mean that creating a virtual E. coli will be a snap. Many mysteries remain to be solved, and at the moment even a single E. coli may be too complex to recreate in a computer. But the effort is still worthwhile, some scientists argue, because it would become a powerful tool for drug testing, genetic engineering and for understanding some of life's deepest mysteries. Discovered in 1885, Escherichia coli soon proved easy to raise in laboratories. Its popularity boomed in the 1940's when scientists figured out how to use it to pry open the secrets of genes. In the 1970's scientists figured out how to insert foreign DNA into E. coli, turning them into biochemical factories that could churn out valuable compounds like insulin. ... Research on E. coli accelerated even more after 1997, when scientists published its entire genome. Scientists were able to survey all 4,288 of its genes, discovering how groups of them worked together to break down food, make new copies of DNA and do other tasks. Some scientists speculated that before long they might understand how all of the pieces of E. coli worked together. Such speculations were not new. In 1967, Francis H. C. Crick, the co-discoverer of DNA, and the Nobel Prize-winning biologist Sydney Brenner had called for "the complete solution of E. coli." But the call went unheeded for over 30 years. After all, E. coli contains an estimated 60 million biological molecules. Simulating all of them at once was an absurdly difficult task. But by the late 1990's, it began to look plausible, although not necessarily easy. Despite decades of research, many of E. coli's genes still remain a mystery - "probably around 1,000 genes," Dr. Thomas said. "There's a lot more we need to know about E. coli before we can build a really solid model." ... As knowledge of E. coli grows, scientists are starting to build models of the microbe that capture some of its behavior. "This field is moving forward very aggressively," said Bernhard Palsson of the University of California, San Diego. Dr. Palsson models E. coli's metabolism. ... Meanwhile, researchers at the laboratory of Philippe Cluzel at the University of Chicago have been focusing their efforts on making E. coli swim. The microbe swims with several spinning tails, each driven by a motor revolving 270 times a second. If the tails turn counterclockwise, they all wrap into a bundle that can propel E. coli forward. If the microbe makes the motors turn clockwise, on the other hand, the tails fly apart and send E. coli into a tumble. By alternatively swimming and tumbling, E. coli can navigate through its tiny world. It "decides" which way to spin its motors based on the information it gets from sensors that stud its outer membrane. "It's a big information-processing network," said Thierry Emonet, a research scientist at the University of Chicago. To understand this microbial computer, Dr. Emonet and his colleagues have created a virtual E. coli that can sense its surroundings and decide how to swim. They simulate the chemical reactions that carry signals from sensors to motors, and then track the path a virtual E. coli takes through three-dimensional space. ... Dr. Emonet said he hoped that his model would allow scientists to understand other sorts of decisions made by cells. Cells "decide" to divide in response to certain signals, for example, and runaway cell division can lead to cancer. Understanding the simple decisions of E. coli may help researchers understand the decisions of more complex cells like those in our own bodies. "If you can't understand how a single E. coli is able to find food by passing information from the outside to the inside, there's very little hope for understanding a system like cancer," Dr. Emonet said. A full-blown model of E. coli would be able not only to swim, but eat food, fight off invading viruses, make copies of its DNA, and do many other tasks all at the same time. Scientists agree that building a multitasking model would be a daunting job. "Technically, that's incredibly more difficult," Dr. Thomas said. Dr. Ellison and his colleagues have decided to take the first steps toward creating a full-blown model. They want to begin by simulating a simplified E. coli. "We're going to strip E. coli down to about one-quarter of its original size," Dr. Ellison said. Dr. Wanner is working with colleagues in Japan to make this minimal E. coli. "We're trying to knock out groups of 100 genes at a time," Dr. Wanner said. They hope to produce a stripped-down E. coli with only around 1,000 genes within two years. .... The researchers hope to use the model to recreate an entire E. coli, complete with genes, enzymes, membrane channels and other parts. There is one major catch, however. Even a stripped-down E. coli is so complex that no existing program can simulate it. "Our gamble in this is that computers are getting more powerful, so we build the framework and within 5 or 10 years the computers will be able to deal with this," Dr. Ellison said. "Assuming the speed of computing keeps increasing, I don't see why it's not possible," said Dr. Emonet ... But, like some other scientists, he has some reservations about its usefulness. "Even if we could make a simulation of everything inside E. coli today, that does not mean we would understand it," he said "The trick is to build the thing in steps and check that you understand the phenomena one at a time." A full-blown model of E. coli is still worth the effort, many scientists argue, because of its potential benefits. Scientists could
adapt the E. coli model to more complex human cells to simulate how they react to different drugs. "Then you can really do genetic engineering," Dr. Ellison said. "I mean where you can actually design an organism or change it in massive ways. When people talk about genetic engineering today, it's really kind of a joke because they mean, 'I moved a gene from one organism into another organism, and I'm going to pray that it works.' " A virtual E. coli could allow scientists to see in advance how major changes to the microbe would affect it. "That opens up a huge amount of opportunity," Dr. Ellison said. ...
[Personally I doubt that they could ever completly model an entire bacterium like E. coli. And even if they did, the simulation would be so complex that no human mind could understand it. But it will be interesting if they work out its the information content. The "motor revolving 270 times a second" that is controlled by "a big information-processing network" is none other than the bacterial flagellum! It will be particularly interesting if they can work out the information content of that!]
Stephen E. Jones, BSc (Biol)
"Problems of Evolution"

4 comments:

John A. Davison said...

The Semi-meiotic Hypopthesis provides the cytological basis for the instantaneous production of each of the dozen or so chromosomal rearrangements that distinguish us from our chimpanzee cousins. Such all-or-none events have no intermediate states and provide an adequate explanation for the saltational evolution of man from his Primate ancestors.

Assuming each of the rearranements occurred independently, one can conclude that there were exactly that number of intermediate species separating us from our chimp cousins, an estimate certainly in accord with what we know from the fossil record. Such an evolution can never be reconciled with the Darwinian model and apparently proceeded entirely independently of any environmental influences. The first meiotic division is the most likely instrument for this saltational evolutionary model.

Stephen E. Jones said...

John

JD>The Semi-meiotic Hypopthesis provides the cytological basis for the instantaneous production of each of the dozen or so chromosomal rearrangements that distinguish us from our chimpanzee cousins.

Thanks for your comments. First, I agree with the thesis that chromosomal rearrangements have a (if not *the*) major role in speciation, and as this quote I found researching an assignment for one of my biology degree units:

"The role of chromosomal rearrangements in speciation has been considered in Chapters 3 and 6. More and more, it appears as if such rearrangements, of many different types, have played the *primary* role in the *majority* of speciation events. It by no means follows, however, that their significance in speciation is always of the same type. In fact, each chromosomal rearrangement-whether fusion or dissociation, translocation, inversion, gain or loss of heterochromatin-must be regarded as a *unique* event whose consequences will be almost impossible to predict in the present stage of our knowledge. It is thus extremely difficult to incorporate chromosomal rearrangements into mathematical models of speciation and phyletic evolution, which may be one reason why they have been relatively neglected by many evolutionary geneticists."
(White M.J.D., "Modes of Speciation," W.H. Freeman & Co: San Francisco CA, 1978, p.336. My emphasis)

As can be seen, White states that: 1) "chromosomal rearrangements … have played the *primary* role in the *majority* of speciation events" (my emphasis); and 2) this mode of speciation has "been relatively neglected by … evolutionary geneticists" because "each chromosomal rearrangement … [is] a *unique* event whose consequences [are] … almost impossible to predict" and therefore "It is … extremely difficult to incorporate chromosomal rearrangements into mathematical models of speciation and phyletic evolution".

IOW, chromosome mutations do not fit the Neo-Darwinian paradigm of the natural selection of random genetic point micromutation, so they are just ignored. Moreover, if "chromosomal rearrangements … *have* played the primary role in the majority of speciation events", then Darwinism would only be a theory at or below (not above) the species level. And evolution would then be "a
specific sequence of unique events, no different from, say, the history of England" than a science:

"Popper himself, in "The Poverty of Historicism" singles out evolutionary theory for an attack. "Can there be a law of evolution?" "No, the search for the law of the 'unvarying order' in evolution cannot possibly fall within the scope of scientific method...". By this, Popper means only that the history of living organisms and their transformations on Earth are a specific sequence of unique events, no different from, say, the history of England. Since it is a unique sequence, no generalities can be constructed about it." (Lewontin R.C., "Testing the Theory of Natural Selection," review of Creed R., ed., "Ecological Genetics and Evolution," Blackwell: Oxford, 1971, in Nature, Vol. 236, March 24, 1972, p.181. Ellipses in original.)

But there are major problems for a *naturalistic* theory of macroevolution by chromosomal mutations. The most obvious are what both Dawkins and Goul refer to: 1) the problem of a macromutant finding a compatible mate: "if a new species really did arise in a single mutational step, members of the new species might have a hard time finding mates" & "With whom shall Athena born from Zeus's brow mate? All her relatives are members of another species"; and 2) the problem of the macromutant and its offspring surviving: "What is the chance of producing Athena in the first place, rather than a deformed monster? Major disruptions of entire genetic systems do not produce favored or even viable creatures.":

"So, macromutations do happen. But do they play a role in evolution? People called saltationists believe that macromutations are a means by which major jumps in evolution could take place in a single generation. Richard Goldschmidt ... was a true saltationist. If saltationism were true, apparent 'gaps' in the fossil record needn't be gaps at all. For example, a saltationist might believe that the transition from sloping-browed _Australopithecus_ to dome-browed _Homo sapiens_ took place in a single macromutational step, in a single generation. The difference in form between the two species is probably less than the difference between a normal and an antennapaedic fruitfully, and it is theoretically conceivable that the first _Homo sapiens_ was a freak child - probably an ostracized and persecuted one - of two normal _Australopithecus_ parents. There are very good reasons for rejecting all such saltationist theories of evolution. One rather boring reason is that if a new species really did arise in a single mutational step, members of the new species might have a hard time finding mates." (Dawkins R., "The Blind Watchmaker," [1986], Penguin: London, 1991, reprint, p.231)

"We can well imagine such a non-Darwinian theory of discontinuous change-profound and abrupt genetic alteration luckily (now and then) making a new species all at once. Hugo de Vries, the famous Dutch botanist supported such a theory early in this century. But these notions seem to present insuperable difficulties. With whom shall Athena born from Zeus's brow mate? All her relatives are members of another species. What is the chance of producing Athena in the first place, rather than a deformed monster? Major disruptions of entire genetic systems do not produce favored or even viable creatures."
(Gould S.J., "The Return of the Hopeful Monster," in "The Panda's Thumb: More Reflections in Natural History," [1980], Penguin: London, 1990, reprint, pp.158-159)

However, an Intelligent Designer (e.g. the Christian God) could cause complementary macromutations to occur in a male and female in the same population at the same time and place, such that they would mate with each other and since their chromosomes matched, their offspring would be viable.

Dawkins himself explains how "if we were skilled enough at genetic engineering, we could move from any point in animal space to any other point … If only we knew which genes to tinker with, which bits of chromosome to duplicate, invert or delete":

"There is another mathematical space filled, not with nine-gened biomorphs but with flesh and blood animals made of billions of cells, each containing tens of thousands of genes. This is not biomorph space but real genetic space. The actual animals that have ever lived on Earth are a tiny subset of the theoretical animals that could exist. These real animals are the products of a very small number of evolutionary trajectories through genetic space. The vast majority of theoretical trajectories through animal space give rise to impossible monsters. Real animals are dotted around here and there among the hypothetical monsters, each perched in its own unique place in genetic hyperspace. Each real animal is surrounded by a little cluster of neighbours, most of whom have never existed, but a few of whom are its ancestors, its descendants and its cousins. Sitting somewhere in this huge mathematical space are humans and hyenas, amoebas and aardvarks, flatworms and squids, dodos and dinosaurs. In theory, if we were skilled enough at genetic engineering, we could move from any point in animal space to any other point. From any starting point we could move through the maze in such a way as to recreate the dodo, the tyrannosaur and trilobites. If only we knew which genes to tinker with, which bits of chromosome to duplicate, invert or delete. I doubt if we shall ever know enough to do it, but these dear dead creatures are lurking there forever in their private corners of that huge genetic hypervolume, waiting to be found if we but had the knowledge to navigate the right course through the maze." (Dawkins R., "The Blind Watchmaker," [1986], Penguin: London, 1991, reprint, p.73)

But an omniscient, omnipotent Genetic Engineer (i.e. the Christian God) *would* know "which genes to tinker with, which bits of chromosome to duplicate, invert or delete" (e.g. to build a human from an ape)!

I will develop this proposed mechanism in my second book, "Progressive Creation: A Scientific General Theory of Creation"
[http://members.iinet.net.au/~sejones/pc00summ.html]

JD>Such all-or-none events have no intermediate states and provide an adequate explanation for the saltational evolution of man from his Primate ancestors.

Agreed about the "no intermediate states" but disagree about the "evolution" (see above and previous).

JD>Assuming each of the rearranements occurred independently, one can conclude that there were exactly that number of intermediate species separating us from our chimp cousins, an estimate certainly in accord with what we know from the fossil record.

Thanks for confirming that. But you are tacitly conceding the mate problem above. If the macromutant could mate and have viable offspring with its parent species, the macromutation would be reabsorbed by the population (see tagline-which BTW supports the speciation by chromosomal mutation mechanism). The fact that "each of the rearrangements" would create a new "species" means there would have to be *two* compatible macromutations in a male and female near in time and space.

But metaphysical naturalists like Dawkins and Gould (and yourself) know the improbability of this occurring even *once*, let alone thousands (if not millions) of times in the history of life, especially in a progressive, coordinated series* towards a distant goal, e.g. humans:

"Gradualists and saltationists alike are completely incapable of giving a convincing explanation of the quasi-simultaneous emergence of a number of biological systems that distinguish human beings from the higher primates: bipedalism, with the concomitant modification of the pelvis, and, without a doubt, the cerebellum, a much more dexterous hand, with fingerprints conferring an especially fine tactile sense; the modifications of the pharynx which permits phonation; the modification of the central nervous system, notably at the level of the temporal lobes, permitting the specific recognition of speech. From the point of view of embryogenesis, these anatomical systems are completely different from one another. Each modification constitutes a gift, a bequest from a primate family to its descendants. It is astonishing that these gifts should have developed simultaneously. Some biologists speak of a predisposition of the genome. Can anyone actually recover the predisposition, supposing that it actually existed? Was it present in the first of the fish? The reality is that we are confronted with total conceptual bankruptcy." (Schutzenberger M-P., in "The Miracles of Darwinism: Interview with Marcel-Paul Schutzenberger," Origins & Design, Vol. 17, No. 2, Spring 1996, pp.10-15. http://www.arn.org/docs/odesign/od172/schutz172.htm)

is *astronomical* and *way* beyond what an unintelligent, `blind watchmaker', natural process could reasonably be expected to achieve.

JD>Such an evolution can never be reconciled with the Darwinian model and apparently proceeded entirely independently of any environmental influences. The first meiotic division is the most likely instrument for this saltational evolutionary model.

Agreed. But you are not facing up to the mate problem (see above).

So what you call a "saltational evolutionary model" I call my Progressive (Mediate) *Creation* model.

But as I have said, 10+ years of debating evolutionists on three different lists has shown me that, because of our radically different metaphysical starting assumptions about God, there is no point us wasting each other's time and getting frustrated discussing anything that depends on those assumptions (e.g. whether it was "evolution" or "creation"), but our positions must pass by each other like ships in the night.

Steve

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"But continuing unhappiness, justified this time, focuses upon claims that speciation causes significant morphological change, for no validation of such a position has emerged (while the frequency and efficacy of our original supporting notion, Mayr's "genetic revolution" in peripheral isolates, has been questioned) Moreover, reasonable arguments for potential change throughout the history of lineages have been advanced although the empirics of stasis throws the efficacy of such processes into doubt. The pattern of punctuated equilibrium exists (at predominant relative frequency, we would argue) and is robust. Eppur non si muove; but why then? For the association of morphological change with speciation remains as a major pattern in the fossil record. We believe that the solution to this dilemma may be provided in a brilliant but neglected suggestion of Futuyma [Futuyma D.J., "On the role of species in anagenesis," American Naturalist, Vol. 130, 1987, pp.465-473)] He holds that morphological change may accumulate anywhere along the geological trajectory of a species. But unless that change be `locked up' by acquisition of reproductive isolation (that is speciation), it cannot persist or accumulate and must be washed out during the complexity of interdigitation through time among varying populations of a species. Thus, species are not special because their origin permits a unique moment for instigating change, but because they provide the only mechanism for protecting change. Futuyma writes: `In the absence of reproductive isolation, differentiation is broken down by recombination. Given reproductive isolation, however, a species can retain its distinctive complex of characters as its spatial distribution changes along with that of its habitat or niche...Although speciation does not accelerate evolution within populations, it provides morphological changes with enough permanence to be registered in the fossil record. Thus, it is plausible to expect many evolutionary changes in the fossil record to be associated with speciation.' By an extension of the same argument, sequences of speciation are then required for trends: `Each step has had a more than ephemeral existence only because reproductive isolation prevented the slippage consequent on interbreeding other populations...Speciation may facilitate anagenesis by retaining, stepwise, the advances made in any one direction.' Futuyma's simple yet profound insight may help to heal the remaining rifts and integrate punctuated equilibrium into an evolutionary theory hierarchically enriched in its light" (Gould S.J. & Eldredge N., "Punctuated Equilibrium Comes of Age," Nature, 18 November 1993, Vol 366, pp.223-227, pp.226-227. Ellipses in original)
Stephen E. Jones, BSc (Biol).
http://members.iinet.net.au/~sejones
http://creationevolutiondesign.blogspot.com/
http://members.iinet.net.au/~sejones/PoE/PoE00ToC.html
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John A. Davison said...

Chromosome rearrangements are not random and probably never have been as I pointed out in my Prescribed Evolutuonary paper. Certain sites are more prone than others to restructuring.

As for evolution being a unique historical event, I agree with Schindewolf that it cannot be reconstructed or duplicated experimentally. It is precisely these considerations that have led me to abandon both Darwinism and Lamarckism in favor of what seems to me the only viable explanation.

Phylogeny, like ontogeny, has been front-loaded with virtually no role for the environment beyond acting as a stimulus for the release. No role for the environment exists for ontogeny so why should one exist for phylogeny? They are both part of the same organic continuum so we can expect similar properties or at least I can.

I have no idea how many independent front-loadings took place but my present estimate is very many, perhaps even as many as the tens of thousands that Berg postulated. There is no good reason to adhere to a monophyletic origin of the biota and plenty of reasons not to.

In additipn to the Prescribed Evolutionary Hypothesis paper I recommend Davison, J.A., Ontogeny, Phylogeny and the Origin of Biological Information, Rivista di Biologia 93: 513-524, 2000, with an online version available at my home page. www.uvm.edu/~jdavison

That page has been frozen by the University of Vermont since 2000 when I resigned. They were threatening to detenure me if you can imagine such a thing. I resigned just in case. Actually there is no record at UVM that I taught there for 33 years. I guess I proved to be a real embarrassment to them. I sure hope so.

John A. Davison said...

There are no problems with finding a mate either as it is perfectly clear that semi-meiotically (gynogenetically) produced offspring can be of both sexes. Even in ordinary sexual reproduction excess males can be produced by simply delaying fertlization in frogs. I recommend for a detailed treatment of these matters including the comments by M.J.D. White, "An Evolutionary Manifesto: A New Hypothesis for Organic Change" also available at my home page and elsewhere on the internet where it has been largely ignored when not being ridiculed. It earned my most cherished award, "The Crankiest." Isn't that precious?

Without endorsing any Christian beliefs, virgin semi-meiosis can produce both males and females, at least in frogs, thus providing a basis for both the immaculate conception of Mary and her child, Jesus.