Evolution and male/female

Discussion in 'Creation vs. Evolution' started by Administrator2, Feb 20, 2003.

  1. Administrator2

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    PHIL HANSON

    I am looking for information about what evolutionists have to say about the development of male and female.

    When you look at their charts, they only show one gender, male, coming up out of the water, and then showing the various mutations on the way to what humans looked like today.

    The Scriptures tell us that God made both male and female.

    GE 1:26 Then God said, "Let us make man in our image, in our likeness, and let them rule over the fish of the sea and the birds of the air, over the livestock, over all the earth, and over all the creatures that move along the ground."

    GE 1:27 So God created man in his own image,
    in the image of God he created him;
    male and female he created them.


    I have never heard, or read, evolutionists discuss the issue of male and female.
    I have looked on the Internet for information, but have found none.
     
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    PAUL OF EUGENE

    Well, I can give you some general information about sex and evolution.

    Evolution is greatly assisted by sex. If beneficial mutation A occurs in individual "a" and beneficial mutation B occurs in individual "b", then sex can bring the two beneficial mutations together over a few generations. Creatures that do without sex - there are a very few of them - have to have all their beneficial mutations one at a time in the same line of descent. And as for harmful mutations, sex allows those to be swapped "out" instead of "in", thereby offering a way for the progeny to escape the defects of the earlier generation. These two affects make a big difference in a populations' ability to maintain itself.

    You of course realize that the swapping out and in occurs randomly. However, those progeny "stuck" with extra "bad" mutations leave fewer or no descendants, taking the bad mutations with them, and those progeny "blessed" with extra "good" mutations live long and prosper, probagating their good mutations. This is the non-random part of the theory of evolution - sometimes called "survival of the fittest".

    That is the "why" of having sex. But another question is, when did sex first come along?

    According to the theory of evolution, sex would have been "invented" way back about the time multi-cellular creatures began to come along. Even single celled bacteria can come together and exchange genes. As cells began to specialize in developing multi-cellular organs, the sex organs would have taken shape along with the rest. When God took the male "Adam" aside, caused him to become a living soul and put him in the garden of Eden, sex had already been around for oh, maybe a billion years. Thus, Adam by himself, was incomplete.

    There is a lot of variation in how the sex method is implemented.

    We mammals use the y chormosone method of determining sex. This is not the only method used. Some creatures don't have variations in the chromosones. Crocodiles, for example, decide what sex to become based on the temperature of the developing egg. Some creatures have both male and female organs, are able to both give and receive insemination. No need to determine sex of offspring there!

    Sex is involved in the actions of certain "selfish genes", for example the "media" gene, possessed by some flour beetles, involves killing offspring that don't have the right "media" gene. You can read about this at http://www.dhushara.com/book/evol/medea.htm . . .

    Is this the kind of thing you wanted to hear?
     
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    PHIL HANSON

    Reproduction in mammals requires a male and female mammal.
    This is the only way you can get a next generation.
    Evolution does not every portray both male and female, from what I
    have seen and read.
    Evolution does not explain how there could be both male and female,
    or how male and female developed independently of each other.

    "Today, there are about 4,000 kinds of placental mammals,
    ranging from humans, to dogs, cats, whales and bats."
    A quote from a science article at CNN.

    This means that at some time in the past, there had to be the
    development of a male and female for these 4,000 kinds, within the
    same generation. If only the male developed in a generation, then
    you don't get a next generation. If only the female developed in a
    generation, then you don't get a next generation. And then you have
    the problem of them finding each other. What is the male and female
    of certain kind of mammal developed in different locations? Then you
    don't get a next generation.

    Evolutionary theory seems to just assume that there is a male and a
    female in the same generation.
    This means that the male and female would develop completely in the
    same generation.
    This means that you would have a fully developed male and female,
    both able to sexually reproduce, in the same generation.

    The development of a male and female mammal could not have happened
    over time; thousands or millions of years.
    It would have had to have happened within a few years, so that this
    pair could reproduce, and have a next generation.

    How does evolutionary theory explain the development of a male and
    female within a single generation, so that they could reproduce, and
    have a next generation?
     
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    HELEN

    Hi Phil. Evolutionists have a lot to say – about how confusing sexual evolution really is. They have no explanation for it. Yet it exists in every major animal division.

    The main problem is that evolution posits that the genetic information is primary, and that the passing of it on to the next generation is the reason for reproduction of any kind. This is most efficiently done through asexual reproduction, not through sexual reproduction. The entire genome is passed on when reproduction is asexual. With sexual reproduction there is a 50% loss. That is an enormous loss! There is no evolutionary reason for sexual reproduction to exist, let alone so extensively.

    You are right about not finding much out about it on the internet. However Walter ReMine found out a great deal of what evolutionists say about the development of sexual reproduction in his book The Biotic Message, and here are some of the quotes he lists from evolutionists:

    Sex is the queen of problems in evolutionary biology. Perhaps no other natural phenomenon has aroused so much interest; certainly none has sowed as much confusion. The insights of Darwin and Mendel, which have illuminated so many mysteries, have so far failed to shed more than a dim and wavering light on the central mystery of sexuality, emphasizing its obscurity by its very isolation.
    G. Bell, The Masterpiece of Nature: The Evolution and Genetics of Sexuality, University of California Press, 1982

    Yet puzzles remain. One problem is the existence of six. … Despite some ingenious suggestions by orthodox Darwinians there is no convincing Darwinian history for the emergence of sexual reproduction.
    P. Kitcher, Abusing Science: The Case Against Creationism, MIT Press, 1982

    In discussions about the origin of sex in nature, evolutionist literature abounds with words such as ‘enigma,’ ‘problem,’ ‘curiosity,’ and the like, indicating they are not at all sure of the origin of this method of reproduction, especially being as prevalent as it is, while dividing the inherited traits approximately in half for each offspring each time. While this does produce a great amount of variation, it also has a strong tendency to eliminate mutations of any variety, simply by virtue of the numbers of combinations that are involved in a sexually reproducing population.

    Although the following does not bear directly on the origin of sexual reproduction, it is an expression of the confusion faced by evolutionists regarding the function of sexual selection and such. In other words, by refusing the biblical explanation as ‘religious’, they nevertheless have nothing better to offer:

    To Paul of Eugene:
    Evolution is not greatly assisted by sex; it is, on the contrary, greatly hindered by sex. Mutations are generally eliminated by sexual reproduction, unlike asexual reproduction which passes them on in totality.

    Please note the following from an expert in the field:

    The primary task for anyone wishing to show favorable selection of sex is to find a previously unsuspected 50% advantage to balance the 50% cost of meiosis. Anyone familiar with accepted evolutionary thought will realize what an unlikely sort of quest this is. We know that a net selective disadvantage of 1% would cause a gene to be lost rapidly in most populations, and sex has a known disadvantage of 50%. The problem has been examined by some of the most distinguished of evolutionary theorists, but they have either failed to find any reproductive advantage in sexual reproduction, or have merely showed the formal possibility of weak advantages that would probably not be adequate to balance even modest recombinational load. Nothing remotely approaching an advantage that could balance the cost of meiosis has been suggested. The impossibility of sex being an immediate reproductive adaptation in higher organisms would seem to be as firmly established a conclusion as can be found in current evolutionary thought. Yet this conclusion must surely be wrong. All around us are plant and animal populations with both asexual and sexual reproduction.
    G.C. Willaims, Sex and Evolutions, Princeton University Press, Princeton, 1975

    That is the most explicit quote I know of, but others like G. Bell, Maynard Smith, Kitcher, and even Dawkins consistently, in the past, have acknowledged the puzzle presented by a type of reproduction which not only produces a 50% cost to the genome, but eliminates most mutations as well.

    And in order to say sex had been around for a billion years before Adam is to explicitly deny what the Bible says.
     
  5. Administrator2

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    PAUL OF EUGENE

    Hi Phil! Greetings from Eugene, Oregon! May the Lord bless you with an alert mind and opportunities to witness in His name.

    Thank you for explaining your particular concerns. It seems that your understanding of evolution is focused on the individual. A single offspring, perhaps, leaves the others and goes off to found a new species. But this is not the way evolutionists actually think evolution occurs. Rather, a whole population evolves at once, over a time frame spanning a lot of generations. So when woodpeckers were developing from more ordinary birds, there was never a time when a completely ordinary bird and a completely formed woodpecker were competing for the same mate. Instead, a lady woodpecker would have to choose between two birds, one of which (in her generation) had a slightly larger bill than the other. Or perhaps the competition was that birds in one nest starved while birds in another survived due to their parents slightly tougher bills with consequent improved bug catching ability . At the same time, woodpeckers with plainer heads were loosing out in the competition for females with woodpeckers with brighter heads. And so forth. So there was never a time when pre-woodpecker pairs were incompatible as they became more and more like the modern form of woodpecker.

    Probably, as well, your thinking is also not fully adapted to the evolutionist view that there were vast spans of time available for all this to take place in. Many biblical literalists, perhaps including yourself, habitually think of all history occurring within 6000 years more or less, while to the evolutionist, 200,000 years would be but a blink of an eye so to speak in geological time! Yet over that span a species of bird that eats bugs under the bark of trees could easily develop from plain beaks into shock mounted wood drillers such as we have today in the woodpeckers, with each generation seeing such a slight change that your projected problem of leaving the opposite sex behind as evolution procedes never has a chance to occur.

    I hope this helps you see why evolutionists aren't particularly concerned over the matter of the opposite sex being a special problem every time a new species is formed.

    * * *

    [the following is from a second email on the same day]

    Hi Helen!
    In your post to Phil, you had this to say:

    There are very good reasons for sexual reproduction to exist! It's not as if every once in a while, non-sexual reproduction doesn't pop up and have its chance. Whiptail lizards, for example, are a species that do not bother with sex for reproductive purposes. Over the years I've discovered that a web search for "whiptail lizard" always comes up with some interesting sites. Try it out! You are sure to find some that will point out the disadvantages to the whiptail lizard species for having to live without a gene shuffling mechanism such as sex.

    Do you recall your own confident proclamations that accumulating mutations would eventually doom any given species due to "genetic load?" And here you explain yourself just how sex can help alleviate the problem of accumulating harmful mutations! We evolutionists must remember to thank you for that point on our side, and for noting the role sex has in helping that to happen. I wouldn't say it just the way you did - I'll try to describe how that happens in my own way in a bit.

    That was a good article by Stephanie Chasteen. Thanks for supplying it.

    Then you addressed some comments to me . . .

    Do you still have your February 2003 Scientific American hanging around the house? Check out the article on Page 52 and following, where the authors describe using computer simulated evolution to evolve useful electronics. In particular, note the diagram on top right of page 55. There, the article describes swapping "parts" in crossover fashion as a method of enhancing the efficacy of their Darwinian Evolutionary technique for creating novel and useful devices. This, of course, is the essense of sexual genetic shuffling!

    Every computer simulation of Darwinian Evolution always includes genetic swapping just because it speeds up the results!

    Now I'm going to attempt to make it clear why this works.

    Suppose I have a bad mutation in a sperm, one that causes the child to die when they reach puberty. If I reproduce without sex, every one of my kids will have that mutation, and they all die before they can have kids. Too bad! My line, regardless of the high quality of the rest of the genes, dies out.

    But we humans have sex. So when my chromosones divide - the one with the bad mutation goes to some sperm and the one without goes to other sperm. So half my kids can go on to have kids of their own anyway!

    OK now lets reverse the mutation, make it beneficial. This time, the gene makes the kid have a bank account of a million dollars on reaching puberty. Without sex, if I reproduce, all my kids have that good fortune, they have no trouble eating enough to be able to reproduce later.

    With sex, only half my kids get the million dollars. Seems a bummer, but the helper gene does, in fact, get its chance to help some of my kids.

    So with sex, the rate of beneficial mutations probagation is slower, but consider this: Its got to be pretty slow anyway, since beneficial mutations are so rare. Many mutations are neutral and a lot of them are harmful. And there is also the chance for beneficial mutations to happen in two seperate individuals and then come together!

    In my crazy example of the million dollar gene, suppose that another parent out here in Eugene has a child with the benefical gene of financial acumen. Unfortunately, they are not rich enough for the child to have much scope for her powers. But she grows up and marrys one of my million dollar offspring and the two genes seem to work well together in the kids. That couldn't happen at ALL without sex to bring them together. Instead, my line would have to wait for the time required for that financial acumen gene to occur again spontaneously in one of my direct descendants. So in a population of over a million individuals one of the benefits is, more than one gene can be being invented and tested at the same time, and combined when they start to spread into the population as a whole!

    But these things are amenable to computer simulation. Would you like for me to devise a program that we could run and see how evolution procedes, with and without sex, for purposes of comparison? Perhaps this has already been done.
     
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    HELEN

    Paul:

    1. One single offspring cannot found a new population unless it is an asexually reproducing organism. Even then, the chances of an entire population resulting from that one is not known of in biology, so if you could give an actual example, I would be fascinated and more educated.

    2. There is no known instance of us seeing a population of anything evolve into more than a very simple variation of the original population. The type of variation we actually see in real life does not lead to the formation of a different type of animal. Bones do not change. Breathing mechanisms do not change. Heart chambers do not change. And so it goes. All that changes that we have ever seen are slight predominances of color and size. We have seen some things lost, such as sight in the blind cave fish, but we have not, as yet, been privileged to see anything gained in terms of a new form or function. This is the reason that we refer to the evolutionary scenario as imaginary.

    3. You will find that, in actual real life studies done on mate selection, the ability to find food or other things which are primary to life often has little to do with it! I guess living organisms don't pay much attention to computer programs. At any rate, what you offered in this area was complete imagination. Imagination is nice, but it doesn't replace what really happens in real living nature.

    4. Vast spans of time? Evolution doesn't have nearly enough time even if it could happen (which, genetically, it can't seem to). For instance, the point is NOT years, but generation times. For instance, a bacterial generation time is about 20 minutes. Human generation time, at the minimum, is probably about 14 years. That's the time it takes from the beginning of the next generation until that generation is capable of reproducing itself. Now, it has been estimated by evolutionists that it took the earliest one-celled organism about a billion years to become a multi-celled organism with the simplest kind of cellular differentiation involved. Figure an hour generation time. That's about 24 generations on a good day. Let's be conservative and cut that to ten, since not all days are good days. That's 3650 generations a year. Times a billion. That's 3,650,000,000,000 GENERATIONS to get to the first multicelled organisms. Now please go from fish to primate. Averaging out generation times, let's settle for a year -- something much shorter than any primate is capable of -- but fine to get my point across. You now need three and a half billion years minimum to get some reasonable changes established. Add the billion years it took to get the one-celled organism to a multi-celled organism. Add the amount of time required to get that multi-celled organism to a fish. Evolution does not have enough time if you double or triple the age of the earth given by evolutionists!

    5. If there are very good reasons for sexual reproduction to exist, evolutionarily, please inform the evolutionary geneticists and theorists, for they can't find any.

    6. The very fact that whiptails and some crawfish etc. can reproduce asexually shows that sexual reproduction is not necessary! And yet it is prevalent. Reason? Evolutionarily unknown. Biblically, because God did that to prevent mutations from building up in a population too fast. Sexual reproduction slows down genetic load build-up.

    7. Sexual reproduction only slows down genetic load build-up, it does not eliminate it. I strongly suggest a course in population genetics if you want to argue in this area, Paul. Or at least get a text on it and read it.

    And, finally, as far as computer simulations go, I'm afraid real life confuses them every time. I'll stick to the actual data, thanks, and not to the programs intelligently designed (by the way) by some human who is trying out a new idea or even working with an old one. As I said above, imagination is nice, but it doesn't take the place of real life.

    And real life denies evolution in terms of time, chance, mutations, and natural selection -- the exact four things evolution depends on. Sexual reproduction increases variation which already exists within the genome but reduces the number of mutations which have the potential of spreading throughout a population. Sexual reproduction, biologically, appears designed to slow down genetic load and stop mutational damage.
     
  7. Administrator2

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    PAUL OF EUGENE

    Hi Helen! Thanks for your reply. May the Lord continue to give you health and opportunities of service. On with the debate:

    Just what I told Phil. Evolution procedes for the population as a whole, not for a single individual. Only asexual creatures can singly found a whole population.

    I know you don't believe in evolution. We evolutionists say the opposite, there is no known instance of a living creature that got here EXCEPT by evolution! Did I ever tell you about when I was a child watching the clock hands on the wall? I told my mother they weren't moving. She told me they were, but just to slowly for me to see. I thought she was wrong, but she was right. And the same goes for evolutionary changes - how long have we really been watching? We see the kinds of changes evolutionist predict we would see in the time we have had to watch. It is unreasonable to ask for more than that.

    I have it on very good authority that some creationists believe life is not subject to numerical analysis such as this. The actual quote is . . . "as far as computer simulations go, I'm afraid real life confuses them every time. I'll stick to the actual data, thanks . . ." and I think you have a certain amount of respect for that logic.

    However, I don't agree with that kind of thinking, so instead I'll critique your assumptions.

    You are not taking into account the handicaps that first life worked with . . . having to devise the genetic code, invent sex, invent cells, invent mitochondria, invent cell nucleii; and then multicellular life and then master control genes able to shut off or turn on whole features - such as completely suppressing teeth in birds, for example, although some scientists have experimentally turned on the bird genes for teeth! These developments greatly speeded up the pace of evolution, setting aside your calculations based on the pokey beginning times.

    Internet searches aren't completely without ANY results! However, like you, I am surprised there is so little there. There are books you can buy on the subject, but where are the internet articles? There are only a few here and there. Here's a good one:
    http://www.interciencia.org/v21_06/art04/

    I don't understand something. How come you claim this to be a "biblical" benefit . . . when the Bible says NOTHING about sex slowing down genetic load buildup? Of course, I agree with you that it does slow it down, but where is that in the Bible? I know where it says he made us male and female. I'm looking for the link with genetic load.

    And then you say I can't claim the exact benefit you acknowledge as an evolutionary reason for having it there? Why not? Let me put it this way. Why are you so sure that sexual reproduction, which slows down genetic load build-up, doesn't completely overcome genetic load buildup? And if it does, then wouldn't that explain why its the sexual reproducing organisms that stick with us over the long history of life?

    Oh yes, I knew that quote came from somebody you would respect! It was you all along! But as I explained, I think that properly done, computer simulations can be informative. And its not as if we couldn't compare the results to real life, after all. Scientists do that all the time these days, work out computer simulations, compare the results to real life, and if they work in the areas they can check, take the simulation for evidence of what is happening in related areas that they cannot otherwise check.

    Now I have in mind very basic simulations. For example, take a gene. Give it a value of 5, admittedly an arbitrary number. Now lets estimate that the organism with this gene has a prospect of living and reproducing of 50%. OK? Now we wish to simulate a harmfull mutation. So we push that gene from value of 5 to value of 4. Now we estimate that the organism with this gene has a prospect of living and reproducing at 40%. In our simulation, we will be adjusting the odds of survival accordingly.

    See, we just want to see how a harmful gene works out in a simulation. So we don't have to specify what the drawbacks actually are - we just say it has them somehow. All for the purpose of seeing what a harmful gene will do down the line, if we follow the known rules of heredity, for example.

    So that would be, in very small part, how such a simulation would be constructed. We'd have to put out a bunch of the organisms, simulate more than one gene at a time, and so forth . . .

    Now if you want to say that you are absolutely sure that genetic load will accumulate and kill off whole species, regardless of the saving "grace" of sexual recombination, how can you possibly also say that simulations of such harmful genes are all invalid? You must have, in your mind, some kind of model of how the genes will play out. Therefore you believe modelling is valid, after all! So the only question is, how to put together a valid model. Can you share with us the details of your model that asserts all species eventually accumulate fatal genetic load, with sexual recombination unable to halt it? Of course, if you continue to insist all models are invalid, then you must give up being able to say you are certain genetic load will kill off a species. Which is it to be?
     
  8. Paul of Eugene

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    Paul of Eugene here.

    OK I've created a little evolution emulator program.

    It allows you to specify a string of genes of "any" length - but you'd better keep it short, like about 5 to 20 . . . .

    It allows you to specify the number of creatures the "environment" will "support", but you should keep that under 500 . . . . and less than that for "full size" of 20 genes.

    The thing is written in DOS BASIC, you see, and is limited to the BASIC string space. About 10,000 genes is all it has room for, considering we have to temporarily triple the number every generation. Perhaps I'll rewrite it someday to keep the genes in disk space. This will allow for a generation with a million individual gene strings. I shudder to think of the time it will take to run THAT simulation.

    All the genes are initially set at a value of 5. They are allowed to "mutate" upwards and downwards from 0 to 9.

    Mutations are introduced under operator command in batches of whatever number you specify at at time. I typically set batches at 25 - 75 for bad and 2 for good.

    A single generation of the gene strings is run in the computer by doing the following:

    a) First we probagate. We construct two times as many new creatures as presently exist by randomly copying the old creatures. If genetic exchange is enabled, we randomly select a mixing point and then randomly select a second old generation gene string and stick in the genes from the second gene string up to that mixing point.

    b) Now we have 3x the sustainable population, so we reduce them to the maximum sustainable size by subjecting them to the trials of life.

    Over and over, a random creature is selected. The genes are added up. We also add up the maximum possible score all the genes could have if they were all nines. We add a little bit to that maximum - just one or two - then we form a fraction out of those two numbers. We compare that fraction to a random number generated by the machine between 0 and 1. If the random number is bigger than the fraction, the creature "dies" - the genetic string is removed from the list. Otherwise, the creature lives. We just keep doing this over and over until the number of gene strings is reduced to our arbitrarily selected viability number.

    Automatically this means genes with higher numbers give the gene string a better chance of survival and genes with lower numbers give the organism a lower chance of survival, but it is not a certainty in any case. After all, in any given generation, the trials of life might even completely skip a given gene string! Not likely, but possible.

    Any gene string with a zero in one of the genes is considered completely unviable and is also removed.

    c) Now we run as many generations as we like. There are provisions for viewing a summary of the genes and for viewing the individual gene strings. There is also a provision for running the generations "forever" and temporarily halting the process to view the summary.

    The results are definate as to the advantages for recombination of the genes. With the recombination turned on - the equivalent of using sex - gene strings of length 10 evolve from initial seeding of all 5's to all 9's in about 4000 generations. This with 50 bad mutations and 2 good ones being inserted every 10 generations. On my 300 megahertz laptop it takes about 45 minutes to run those generations.

    With sex eliminated the average gene value barely budges from the 5 level and shows a large variation of both lower and higher genes in the organisms in the same running time.

    These results can be reproduced over and over with different settings for the various parameters.

    I conclude that genetic exchange greatly assists both evolution and the overcoming of genetic load, defining genetic load as the systematic accumulation of defective genes due to bad mutations.

    Next research project: How many bad mutations must I insert every 10th generation before I finally halt evolutionary progress? Last night I tried setting the bad gene insertion level at 1000, the string length at 5, and the good insertion level at 2, for a population of 500 strings. These "mutations" are set to occur every 10 generations during constant run mode. All nines appeared in about 1800 generations. It seems that the number of generations required to achieve maximum evolutionary benefit is more closely related to how many genes are in the string rather than the number of bad mutations being salted. Seemingly, as long as the genetic "load" is able to be handled, it has little or no affect on the speed with which good mutations take hold. Population size also seems to be relatively unimportant, once there is a population large enough to have reasonable comparisons between individuals taking place. It would appear that once a beneficial mutation has become established and begun to spread, it's coverage over the entire population occurs at an exponentially increasing rate, i.e. just a few generations are required.

    And the compiled program only has 45,056 bytes.
     
  9. Helen

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    1. Your program was intelligently designed
    2. With an end in mind
    3. I still suggest you take a course in population genetics; population size has EVERYTHING to do with it!

    I still prefer going where the actual extant data leads instead of someone making up their own with a computer model!
     
  10. Paul of Eugene

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    Hi Helen! [​IMG]

    Do you have any suggestions as to how we could intelligently redesign it to more accurately simulate what genes would do in real life?

    By the way, I find that whereas with 1000 bad mutations every 10 generations the gene strings could handle the load, with 1500 bad mutations every 10 generations the gene strings all got eliminated. Thats with 2 good mutations at the same time, 500 total strings, 5 genes per string, sexual recombination turned on.
     
  11. Helen

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    Paul, part of the problem with ANY computer model right now is that we don't know what a lot of the genes do! I was looking at the March 6, 2003 issue of Nature this afternoon. There was enough in there to show you all by itself. Here are three things I marked -- their order is as they are bookmarked in the magazine. I think it will give you an idea of the complexity of the situation:

    p xiii, from a highlight of the Molecular Cell Biology journal for March 2003:
    The endoplasmic reticulum 'proof-reads' newly synthesized proteins, so only native conformers reach their destinations...this quality control is important for the fidelity of cellular functions, and how recent work has increased our understanding of the conformation-specific sorting of proteinsat the level of retention and export.

    The reason this is important is to show you that even if you could get your mutations to function so as to make new proteins, they would most probably be weeded out by the checking mechanism found in the ER and dismantled; their parts re-used for recognized proteins which had a known function.

    next is something I don't think you have included in your thinking -- or maybe simply don't know about. Each gene seems to have an interplay of effects along with other genes -- it is not a matter of one gene per trait. Therefore every mutation will have the effect of disturbing a number of traits one way or another. Here is an interesting bit on two seemingly unrelated effects which one protein -- a hormone -- participates in:

    pp 27-28 "Fast and Feel Good?"
    Leptin is a hormone that was shown in 1994 to be mutated in a certain type of obese mouse. It is also produced in humans. Leptin is secreted by adipocytes (fat cells) as well as by other tissues, and the initial studies of its function concentrated on its role in regulating food intake and body weight. Recently, leptin has been implicated more generally in insulin metabolism, nutrient use, reproductive function and the response to stress.

    Leptin also regulates inflammatory and immune responses and directly affects the immune system, especially T cells.


    So there is what one protein does. Interfere with its production via any kind of mutation and what happens? We don't know.

    In addition, there are hot spots in the human genome (and in the genome of every form of life we are aware of) in which mutations tend to happen more frequently than in other areas, and in a 'back and forth' fashion. Did you take these mutations into account? They back-mutate easily, and this is a mutation, too!

    In response to your remark about the size of populations not mattering, on p. 35 is the article "Disease susceptibility in California sea lions."

    Inbreeding in animals can increase their susceptibility to pathogens, but direct evidence from wild populations is scarce and it is unclear whether all pathogens are affected equally. Here we analyse rescued California sea lions afflicted with a range of different pathogens, and find that sick animals have higher-than-normal parental relatedness, with the extent varying among disease classes. our findings indicate that mortality in natural populations may not be entirely random and that inbred individuals could act as more effective reservoirs of infectious agents.

    The smaller the population, the more the inbreeding.

    Population size counts.

    In short, Paul, we don't know enough about genes to make any accurate computer model of mutations and their effects. We don't know enough about the proteins that genes code for. We don't know enough about the combinations achieved through sexual reproduction -- we don't know nearly enough to give your computer model and validity at all.

    We we do see, and what we are finding, is that the cell and its components are vastly more comoplex than we had thought; that genes work by combining with other genes in specific ways and patterns to produce various traits; that we do not know much about the different affects different gene products (proteins) have, etc.

    That is why I prefer to follow the data.
     
  12. Paul of Eugene

    Paul of Eugene
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    Hi Helen!

    Well, the program is not anything but an abstraction. You could say it simulates microevolution but fails to simulate macro evolution. After all, the strings stay the same size all the way down the line! But I primarily designed it to test the potential advantage genetic exchange gives to evolution, which is the subject of this thread after all. The advantage turns out to be enormous, in the little toy universe represented by the simulation. Since (a) The Creator (b) evolution or (c) both the above created us all male and female, I think it helps us understand why.

    I put the program on my web site for downloading by anyone interested. www.epud.net/~richmond is the site, and you have to go to the science page - its at the bottom.
     

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