Tuesday, December 16, 2008

Testing Natural Selection: Part 1

 
The latest issue of Scientific American has an interesting article by H. Allen Orr entitled Testing Natural Selection.
Biologists working with the most sophisticated genetic tools are demonstrating that natural selection plays a greater role in the evolution of genes than even most evolutionists had thought.
Orr is an adaptationist. His perspective on evolution focuses on natural selection as the predominant mechanism. He tends to dismiss all other mechanisms as either uninteresting or unimportant.

I though it might be interesting to compare what a pluralist might say about some of the things in the article. It's one way of highlighting the difference between the two points of view.

Naturally, as a pluralist, I disagree with some statements. My main beef, however, is with the growing tendency to over-emphasize natural selection as we approach the 200th anniversary of Darwin's birth and the 150th anniversary of publication of On the Origin of Species. I think it's possible to describe the differences between evolution in the eighteenth century and evolution in the 21st century without diminishing Darwin's contributions.

Orr begins his article by describing natural selection. He explains that there are several kinds of mutations ...
Most important, we know something about the effects of mutations on fitness. The overwhelming majority of mutations are harmful—that is, they reduce fitness; only a tiny minority are beneficial, increasing fitness.
That's not exactly how I would put it. I would have added that there's a third type of mutation that is neither harmful nor beneficial—neutral mutations.

Furthermore, I would have explained that the frequency of these three different kinds of mutations can vary considerably from one species to the next depending on the organization of the genome. In animals and plants, for example, most of the DNA does not seem to be essential so that the overwhelming majority of mutations are neutral and a smaller number—those that interfere with an essential function—are deleterious. A few mutations can be beneficial.

Orr goes on to say ....
Most mutations are bad for the same reason that most typos in computer code are bad: in finely tuned systems, random tweaks are far more likely to disrupt function than to improve it.
I would not use this analogy because it emphasizes something that I think is false; namely that organisms are "fine tuned systems." I tend to think of them as sloppy Rube Goldberg machines and not as well-tested computer code.

I would say that most mutations in essential regions of the genome are deleterious because random hits in DNA are more likely to make things worse than to make things better. The distinction is subtle, but important. Many adaptationists use language implying that living organisms are almost perfectly adapted to their present environment.

In the next section, Orr describes the advances of population genetics and its influence on how we understand natural selection. I would have described how population genetics led to an understanding of all type of evolution, and not just natural selection. Here's what Orr says,
Population geneticists have also provided insight into natural selection by describing it mathematically. For example, geneticists have shown that the fitter a given type is within a population, the more rapidly it will increase in frequency; indeed, one can calculate just how quickly the increase will occur. Population geneticists have also discovered the surprising fact that natural selection has unimaginably keen “eyes,” which can detect astonishingly small differences in fitness among genetic types. In a population of a million individuals, natural selection can operate on fitness differences as small as one part in a million.
I would have said that the growth of population genetics in the early part of the 20th century led to the recognition of random genetic drift as an important mechanism of evolution. Models were developed to explain how natural selection affected the increase in frequency of a beneficial allele and how neutral alleles could also increase in frequency even though they were invisible to natural selection.

The population geneticists also discovered that harmful alleles could become fixed by accident, although that turns out to be a rare event. More importantly, they discovered that natural selection has a stochastic component. Beneficial alleles will only become fixed part of the time. The probability depends on the fitness advantage. For example, if an allele has a fitness advantage of 10% then it will only become fixed 20% of the time. In 80% of cases when such an allele arises in a population it will be lost by random genetic drift before it becomes fixed.1

As the fitness advantage diminishes, the probability of fixation becomes lower and lower so that alleles with small fitness advantages (<1%) will hardly ever change the species. That's what population geneticists discovered about natural selection.

The probability of fixation of neutral alleles (or nearly neutral alleles) is very low but since there are so many more of them than beneficial alleles, much of evolution is characterized by changes due to random genetic drift.

The next section is "How Common Is Natural Selection?". This is where Orr asks the key question ...
One of the simplest questions biologists can ask about natural selection has, surprisingly, been one of the hardest to answer: To what degree is it responsible for changes in the overall genetic makeup of a population? No one seriously doubts that natural selection drives the evolution of most physical traits in living creatures—there is no other plausible way to explain such large-scale features as beaks, biceps and brains. But there has been serious doubt about the extent of the role of natural selection in guiding change at the molecular level. Just what proportion of all evolutionary change in DNA is driven, over millions of years, by natural selection—as opposed to some other process?
We've discussed this distinction between molecular changes and physical traits many times. One of the most annoying characteristics of adaptationists is that they insist on relegating other mechanisms of evolution to the level of DNA sequences but refuse to consider anything but natural selection when it comes to visible phenotypes. There is no justification for this assumption. Many physical traits can be neutral or even deleterious. They were not fixed by natural selection.2

What Orr says is simply not true. There are many biologists who seriously doubt that natural selection drives the evolution most physical traits, even though such pluralists readily agree that most adaptions are due to natural selection. Random genetic drift is a plausible way to explain many physical traits.
Until the 1960s biologists had assumed that the answer was “almost all,” but a group of population geneticists led by Japanese investigator Motoo Kimura sharply challenged that view. Kimura argued that molecular evolution is not usually driven by “positive” natural selection—in which the environment increases the frequency of a beneficial type that is initially rare. Rather, he said, nearly all the genetic mutations that persist or reach high frequencies in populations are selectively neutral—they have no appreciable effect on fitness one way or the other. (Of course, harmful mutations continue to appear at a high rate, but they can never reach high frequencies in a population and thus are evolutionary dead ends.) Since neutral mutations are essentially invisible in the present environment, such changes can slip silently through a population, substantially altering its genetic composition over time. The process is called random genetic drift; it is the heart of the neutral theory of molecular evolution.
As I've already pointed out, random genetic drift was discovered in the 1920s and it was incorporated into the first version of the Modern Synthesis in the 1940s. It dropped out of favor when the synthesis hardened at the time of the Darwin centennial in 1959.

Random genetic drift was revived in the late 1960's with the discovery of neutral alleles. Drift is the way in which selectively neutral alleles become fixed in a population. Random genetic drift and neutral theory are not synonyms.

As I indicated above, since the vast majority of animal and plant genomes is non-essential, it stands to reason that the vast majority of alleles will be neutral. Thus at the molecular level, at least, random genetic drift must be the dominant mechanism of evolution.

By the 1980s many evolutionary geneticists had accepted the neutral theory. But the data bearing on it were mostly indirect; more direct, critical tests were lacking. Two developments have helped fix that problem. First, population geneticists have devised simple statistical tests for distinguishing neutral changes in the genome from adaptive ones. Second, new technology has enabled entire genomes from many species to be sequenced, providing voluminous data on which these statistical tests can be applied. The new data suggest that the neutral theory underestimated the importance of natural selection.
Hmmm ... I could see where this was going even before I read it. Orr is about to quote the infamous work of Drosophila geneticists who have devised complicated tests to show that some synonymous mutations might confer a selective advantage in one species but not in another closely related species. Some of the papers claim that many alleles in coding regions are not neutral even thought they don't change the amino acid. There's no question that this is true in some cases.

It's also true that mutations altering the amino acid are sometimes beneficial, and therefore selected. However, if you align the amino acid sequences of a given gene from hundreds of species and map them on to the structure of the protein it becomes readily apparent that most substitutions cannot have a significant effect on the function of the protein. They must be neutral, or nearly neutral. As a matter of fact, in most proteins it is difficult to find any clearly beneficial alleles present in one species and not in the others.
In one study a team led by David J. Begun and Charles H. Langley, both at the University of California, Davis, compared the DNA sequences of two species of fruit fly in the genus Drosophila. They analyzed roughly 6,000 genes in each species, noting which genes had diverged since the two species had split off from a common ancestor. By applying a statistical test, they estimated that they could rule out neutral evolution in at least 19 percent of the 6,000 genes; in other words, natural selection drove the evolutionary divergence of a fifth of all genes studied. (Because the statistical test they employed was conservative, the actual proportion could be much larger.) The result does not suggest that neutral evolution is unimportant—after all, some of the remaining 81 percent of genes may have diverged by genetic drift. But it does prove that natural selection plays a bigger role in the divergence of species than most neutral theorists would have guessed. Similar studies have led most evolutionary geneticists to conclude that natural selection is a common driver of evolutionary change even in the sequences of nucleotides in DNA.
Pluralists disagree. We still think that random genetic drift is by far the dominant mechanism at the molecular level and that it even plays a significant role at the level of visible phenotypes.

In addition, we like to remind adaptationists that most beneficial alleles are eliminated by random genetic drift before they ever become fixed in a population.


1. Many biologists, and most evolutionary psychologists, do not understand this important point. They think that all they have to do is identify some (real or imagined) benefit and it will automatically take over the population no matter how small the benefit.

2. I know that Orr said "most" physical traits and not "all" physical traits. It's a distinction without meaning since the percentage of non-adaptive changes that adaptationists are willing to admit, grudgingly, is not much different than zero.

12 comments :

  1. A couple of comments:

    1. Although you seem to be making the charge again, I don’t think Orr (or Dawkins, or other “adaptationists”) dispute that, if you qualify by changes in DNA sequence (wherever those changes occur in the genome), that the bulk of evolution (as so defined) is due to random genetic drift. Moreover, in the last piece of Orr’s article that you quote, he clearly states that he is referring to changes in “genes”, and even here he concedes that the results of the studies he cites show that the majority of differences were due to drift.

    So, I’m missing the point. You end with the pseudo-quantitative claim that genetic drift plays a “significant” role in phenotypically visible changes, but so far (in the couple of years I’ve been a faithful reader of your blog), you have never provided any evidence of a documented instance of this. I won’t dispute the statistical likelihood that it does play a role, but you are making claims about some sort of relative importance in that absence of any evidence.

    Although in theory one can imagine lots of examples where a phenotypically visible trait *could* result purely from random drift, the problem is demonstrating that that is the case. It’s almost like the burden of proving Intelligent Design: in any one instance you have to rule out all the plausible alternatives. (And I’m not sure the data will ever be robust enough in any real world example studied to pin this down.) You have raised several examples in the past that you seem to feel are inexplicable except as products of genetic drift. For example, you previously mentioned epicanthal folds in Asians as something you think is a likely candidate for being due to drift in humans, as it does not appear to have any particular function. Yet animals commonly use external appearance as guides in mate selection, and one benefit of doing so is to avoid mating with closely related species or sub-species (where fertility is often lower). Particularly where the example is a feature of the human face (an object for which our brains seem to have a rather disproportionately well developed pattern-recognition function), the odds that epicanthal folds would be under sexual selection pressure is quite high.

    2. You stated: “For example, if an allele has a fitness advantage of 10% then it will only become fixed 20% of the time. In 80% of cases when such an allele arises in a population it will be lost by random genetic drift before it becomes fixed.

    This could be misleading, so a few comments to help put it in context: the low 20% fixation odds for a 10% fitness advantage is mostly due to the high probability of stochastic events removing the beneficial allele when there are only one or two copies in the population. So your statement is true, and I agree that it is important that biologists recognize this. But it is equally important to understand why, because it really has no bearing on the situation once an allele has established a toehold. Once there are more than a few copies in a population, the chance of that allele being randomly wiped out completely in a single generation due to random events are low, and at that point the odds of becoming fixed go way up. For example, if instead you model a population where 50% of the alleles in a population of 50 individuals give a 10% reproductive advantage, it is virtually certain (>99.9%) to become fixed. (A 5% benefit is fixed 99% of the time, and a 1% benefit will be fixed about 70% of the time). (And you can invert the numbers to see what the complementary fitness penalty would lead to.)

    For an allele that gives a 5% fitness advantage starting from single mutation in one individual in a population of 50 individuals (so initial incidence is 1%), the chance of fixation is about 10%, and a 2% allele will get fixed a bit over 4% of the time. You need about a 40% fitness advantage to have a 50% chance of being fixed. (For comparison, a neutral allele will get fixed 1% of the time in this population). Alleles with a fitness *penalty* above a couple of percent don’t really make it; a 2% fitness penalty will get eliminated 99.9% of the time.

    The point is that most mutations don’t get fixed, and even the beneficial ones are more likely than not to get eliminated. And since there are many more neutral mutation than beneficial ones, most changes that do get fixed will be neutral.

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  2. After 10+ years of persistent prodding by Larry, I've come around to his way of thinking on genetic drift.

    The question must be asked, does that mean I'm becoming a curmudgeon?!

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  3. Chris Nedin asks,

    The question must be asked, does that mean I'm becoming a curmudgeon?!

    Certainly not! That takes another 10 years (and several more visits to Toronto). But keep at it, the gain is worth the pain! :-)

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  4. Speaking of neutral evolution, I recommend Austin Hughes' recent review paper:

    Hughes, A.L. (2008) Near Neutrality: Leading Edge of the Neutral Theory of Molecular Evolution. Annals of the New York Academy of Sciences, 1133, 162-179.

    The nearly neutral theory represents a development of Kimura's neutral theory of molecular evolution that makes testable predictions that go beyond a mere null model. Recent evidence has strongly supported several of these predictions, including the prediction that slightly deleterious variants will accumulate in a species that has undergone a severe bottleneck or in cases where recombination is reduced or absent. Because bottlenecks often occur in speciation and slightly deleterious mutations in coding regions will usually be nonsynonymous, we should expect that the ratio of nonsynonymous to synonymous fixed differences between species should often exceed the ratio of nonsynonymous to synonymous polymorphisms within species. Many data support this prediction, although they have often been wrongly interpreted as evidence for positive Darwinian selection. The use of conceptually flawed tests for positive selection has become widespread in recent years, seriously harming the quest for an understanding of genome evolution. When properly analyzed, many (probably most) claimed cases of positive selection will turn out to involve the fixation of slightly deleterious mutations by genetic drift in bottlenecked populations. Slightly deleterious variants are a transient feature of evolution in the long term, but they have substantially affected contemporary species, including our own.


    Worth reading for many things, including more of Hughes thoughts on problems with detecting positive selection.

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  5. "No one seriously doubts that natural selection drives the evolution of most physical traits in living creatures—there is no other plausible way to explain such large-scale features as beaks, biceps and brains"

    That, in summary , is where Orr's commitment with natural selection is coming from. There is NO OTHER PLAUSIBLE WAY!!! Oh dear!!!


    It's just plain stupid...selection is only part of gthe explanation of how these things come to be. Take exaptaion, for instance. And does orr mena that there is no role for contingency? is natural selection all tehre is to the origin of adapataions?

    "nobody seriously doubts"...a goood phrase to precede an enforced dogma

    The fact is, selection is an important influece, but this does not mena there is nothing else than selection "no toher plausible way", to understand the origin of adaptations. Satements like that form Orr are just brain-dead, dogmatic orthodoxy. All about culutral baggage, little to do with actual biology.

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  6. Presumably drift advocates could point to the fixation of genotypes with strictly deleterious phenotypes as exemplars of drift. The inability of humans to synthesize vitamin C due to fixation of a broken allele of the L-gulonolactone oxidase gene comes to mind.

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  7. After reading Larry's post and Divalent's comment I was wondering, what then are a few dozen transgenic salmon (say the mutation confers no particular advantage in the wild)escapees chances of out-competing wild types?

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  8. Divalent says,

    Although you seem to be making the charge again, I don’t think Orr (or Dawkins, or other “adaptationists”) dispute that, if you qualify by changes in DNA sequence (wherever those changes occur in the genome), that the bulk of evolution (as so defined) is due to random genetic drift. Moreover, in the last piece of Orr’s article that you quote, he clearly states that he is referring to changes in “genes”, and even here he concedes that the results of the studies he cites show that the majority of differences were due to drift.

    It's a question of emphasis and perspective. While it's true that most adapationists don't deny the obvious when pressed, the fact remains that they don't voluntarily disclose the truth if left to their own devices.

    In the Scientific American article, for example, we do not see an unequivocal statement saying that the dominant mechanism of evolution is random genetic drift.

    Instead, we see lots of qualifications questioning that conclusion, including a diagram that emphasizes the role of random genetic drift in preparing for new beneficial alleles.

    Although in theory one can imagine lots of examples where a phenotypically visible trait *could* result purely from random drift, the problem is demonstrating that that is the case. It’s almost like the burden of proving Intelligent Design: in any one instance you have to rule out all the plausible alternatives.

    You are putting the burden of proof on me to show that most visible phenotypes are the result of drift and not adaptation? How come you don't challenge the adaptationists to prove their claim?

    Blood type in humans is one trait that has been shown to be completely consistent with random genetic drift. Another interesting trait is the ability to roll your tongue. Is it up to me to prove beyond a shadow of doubt that this is neutral? In the absence of such a demonstration is it permissible for the adaptionists to simply declare that it must be adaptive because it's visible?

    What about the shape of your nose or whether your second toe is longer than your big toe? Are those assumed by default to be adaptations in the absence of any proof?

    The point is that most mutations don’t get fixed, and even the beneficial ones are more likely than not to get eliminated. And since there are many more neutral mutation than beneficial ones, most changes that do get fixed will be neutral.

    Correct. Is that the impression that a typical reader would have when they finish Orr's article? Do you object to the adaptationist perspective when Orr says, "Population geneticists have also discovered the surprising fact that natural selection has unimaginable "eyes," which can detect astonishingly small differences in genetic types. In a population of a million individuals, natural selection can operate on fitness differences as small as one part in a million"?

    What is the average reader going to take away from reading this? Are they going to understand that a beneficial allele has to confer a significant fitness advantage in order to have a chance of becoming fixed in a typical natural population? Or are they going to think that as long as an allele confers even a minute advantage it will sweep to fixation?

    One of the problems with evolutionary psychologists is that they have latched on to the false adaptationist image that Orr is propagating. Evolutionary psychologists think that as soon as you identify a selective advantage, no matter how small, it will become fixed.

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  9. One thing which I haven't seen given much emphasis in this debate is how changing population size influences the likelihood of mutations surviving long enough for selection to have an effect. If populations are increasing, most individuals would likely produce offspring, and any existing or new mutations they carry would be more likely to increase and be available for selection to work on. This doesn't have to coincide with a bottleneck, but it could.

    Some examples could be annual cycles in population of short-lived species (voles, annual plants), predator-prey cycles (lynx, hares), breakthrough to a new territory (birds on islands, human settlement). With all the current problems with exotic flora and fauna, there's plenty of opportunity for research. This is one example of novel traits being selected in an expanding population. Would it happen the same way if you could do the experiment over? If you had started with 10,000 lizards instead of 5 pairs?

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  10. "However, if you align the amino acid sequences of a given gene from hundreds of species and map them on to the structure of the protein it becomes readily apparent that most substitutions cannot have a significant effect on the function of the protein. They must be neutral, or nearly neutral. As a matter of fact, in most proteins it is difficult to find any clearly beneficial alleles present in one species and not in the others."

    Mapping the amino acid sequences of a protein from different species onto its structure does not give you any information on whether any of the variations observed are due to neutrality. All this variation evolved in the context of its own aminoacid sequence at the time, and thus comparing different sequences that encode the same protein with the same function cannot give you any direct information about neutrality..
    All of the variation may have been selected and been significant in terms of fitness in the context of the sequence at that point in time (although I agree that this is not likely to apply to all mutations)

    Nevertheless the mere presence of diversity in sequence is not evidence for neutrality in its evolution, even if the final phenotype is identical/very similar..

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  11. Oliver says,

    Mapping the amino acid sequences of a protein from different species onto its structure does not give you any information on whether any of the variations observed are due to neutrality.

    Of course it does. If most of the amino acid substitutions are located in loops on the surface of the protein they look much less important than substitutions at or near the active site of the protein.

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  12. Genome linked with culture!
    Listen listen, The Wheel Is Reinvented!
    Plant's Genome Found Linked With Plant's Culture!


    A. listen, listen
    the cat's pissin
    where, where?
    under the chair
    hurry hurry bring the plate
    never mind, it's too late...


    B. New from "Ecological nitrogen-limitation shapes the DNA composition of plant genomes"
    http://mbe.oxfordjournals.org/cgi/content/abstract/msp038

    - "The influence of ecological limitations on the composition of eukaryotic genomes is still unclear"

    - "These findings indicate a fundamental role of nitrogen limitation in the evolution of plant genomes, and they link the genomes with the ecosystem context within which biota evolve."


    C. "Seed of Human-Chimp Genomes Diversity"
    http://blog.360.yahoo.com/blog-P81pQcU1dLBbHgtjQjxG_Q--?cq=1&p=179
    Nov 2005, Dov, in biologicalEvolution forum.

    Biological Evolution's Seeds of Diversity, Human and Chimpanzee/Bonobo Genomes

    Chapter One, In which some wonder what made us human.

    Three recent quotations from Science, representative of many other recent similar statements in various scientific publications:

    1) "Understanding the genetic basis of how genotype generates phenotype will require increasing the accuracy and completeness of the currently available chimpanzee genome sequence, as well as sequencing other primate genomes."

    2)"Can we now provide a DNA-based answer to the fascinating and fundamental question, "What makes us human?" Not at all! Comparison of the human and chimpanzee genomes has not yet offered any major insights into the genetic elements that underlie bipedal locomotion, big brain, linguistic abilities, elaborated abstract thought, or any other unique aspect of the human phenome."

    3)"What makes us human? This question may be answered by comparison of human and chimpanzee genomes and phenomes, and ultimately those of other primates. To this end, we need to understand how genotype generates phenotype, and how this process is influenced by the physical, biological, and cultural environment."

    Chapter Two, In which is explained plainly and succinctly the obvious route by which we evolved,

    i.e. that genotype has not generated phenotype, that we evolved from our genotype via a group of feedback loops. From Science, Vol 308, Issue 5728, 1563-1565 , 10 June 2005, Immunology: Opposites Attract in Differentiating T Cells, Mark Bix, Sunhwa Kim,Anjana Rao:

    "During differentiation, precursor cells with progressively narrowed potential give rise to progeny cells that adopt one of two (or more) divergent cell fates. This choice is influenced by intricate regulatory networks acting at multiple levels. Early in differentiation, precursor cells show low-level activation of all progeny genetic programs. Bias toward a given lineage comes from environmental inputs that activate powerful positive- and negative- feedback loops, which work in concert to impose selective gene expression patterns".

    Chapter Three, In which we explain the revolutionary evolved uniqueness of the human ape's phenotype:

    The 6My-old revolutionary life evolution was initiated by our forefathers who adapted from life in semi- or tropical forest circumstances to life on plains. As changed living posture and circumstances led to modified perceptive/adaptive capabilities and eventually to language communication humans have gradually replaced adaptation to changed circumstances with self-evolving cultures/civilizations for control and modification of much of their circumstances. This is essentially similar to early life's celling evolution, but with culture functioning for humans for change/control of circumstances in lieu of RNA and protein toolings that function for the in-cell genomes for adapting their cell's physiology to changing circumstances.

    Chapter Four, In which appears, may be, genetic evidence/demonstration of the workings of human cultural evolution.

    (a) From Science, 2 Sept 2005: "Page's team compared human and chimp Ys to see whether either lineage has lost functional genes since they split.

    The researchers found that the chimp had indeed suffered the slings and arrows of evolutionary fortune. Of the 16 functional genes in this part of the human Y, chimps had lost the function of five due to mutations. In contrast, humans had all 11 functional genes also seen on the chimp Y. "The human Y chromosome hasn't lost a gene in 6 million years," says Page. "It seems like the demise of the hypothesis of the demise of the Y," says geneticist Andrew Clark of Cornell University in Ithaca, New York."

    (b) But look at this: From Science, Vol 309, 16 Sept 2005, Evolving Sequence and Expression:"An analysis of the evolution of both gene sequences and expression patterns in humans and chimpanzees...shows that...surprisingly, genes expressed in the brain have changed more on the human lineage than on the chimpanzee lineage, not only in terms of gene expression but also in terms of amino acid sequences".

    Surprisingly...???

    Chapter Five and conclusion, In which I suggest that detailed study of other creatures that, like humans, underwent radical change of living circumstances, for example ocean-dwelling mammals, might bring to light unique evolutionary processes and features of evolutionary implications similar to those of humans. end.DH.


    D. How astonishingly wondrous is the familiarity of nowadays researchers with years-old published scientific comprehensions

    From "Factors Involved In Extended Historical Darwinism"
    http://blog.360.yahoo.com/blog-P81pQcU1dLBbHgtjQjxG_Q--?cq=1&p=409

    - Earth Life Is A Real Virtual Affair; it pops in and out of existence in its matrix, which is the energy constrained in Earth's biosphere .

    - Genes are organisms, interdependent members of genes communes, genomes, all continuously undergoing evolution directed towards survival as long as possible, for maintaining Earth's biosphere as long as possible.

    - Culture is a ubiquitous biological entity and is the major effector of genetic evolution, of capabilities and attributes selected for survival.

    - The major course of natural selection is NOT by random mutations followed by survival, but via interdependent, interactive and interenhencing selection of biased replication routes by genes at their alternative-splicing-steps junctions, effected by the cultural feedback of the 3rd stratum multicells organism or monocells community to their prime stratum genes via their 2nd stratum genome organisms.

    - Evolution of life is but a minute component of the evolution of the universe. Cosmic evolution is the evolution of energy. Life, and all objects and processes and natural laws in the universe, are - since none in exsistence at singularity - products of evolution and are continuously further evolving. Everything in the cosmos is fractal, rehappens on many scales, and is continuously evolving. Each and every system in the universe continuously evolves within the total universal evolution and all the systems' evolutions are intertwined and within it life's evolution is the evolution of genes-genomes, continuously evolving in a losing attempt to survive, to maintain - as long as possible - pockets of constrained energy that would otherwise, and anyhow eventually, expand and dilute with the whole mass and energy of the cosmos...

    Dov Henis

    PS: Puzzled why even Darwinians do not comprehend that Darwinism starts all the way back with Life's day one, with the pre-archaea not-yet-genomed-celled genes...


    Exasperated,

    Dov Henis
    (Comments From 22nd Century)

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