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  1. #601  
    I see the odds issue is still holding you back. The main thing you need to keep in mind is that we are talking about self-replicating systems, which means usually exponential growth, and also immense passages of time (billions of years).

    Once we have the first self-replicating cell, if it takes a day to replicate, in 10 days we are talking about a population of 1024, and in a year of 75 000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 organisms (assuming none of them die, but that would only make a small change in the numbers) Thats many many times more than there are stars in the universe.

    Of course in real life these numbers would be limited by things like energy sources, raw material, suitable environment and natural disasters, but it should be clear that one would only need one lucky accident and good conditions for a month or so before life would be so firmly established only a comet strike could eradicate it.

    Next comes the question of mutations. Mutations are actually extremely common, such that our cells have had to develop specific machinery to error check and correct mutations. It doesn't need radiation, just heat or simple errors in copying the genetic code for mutations to take place. In early life mutations would have been rampant, leading to the death of many cells, until a relatively stable robust system emerged. Those same mutations would however also help early life iterate though the solution space very fast, leading to many novel adaptations and innovations.

    Finally, re humans. We are not necessarily the pinnacle of evolution, and the goal the whole system is striving for. 6000 years is really a blink of an eye in evolutionary time, and in the last 10 000 years we have seen great adaptations in human phenotypes for different environments, e.g. dark people for bright climates, and light people for dark climates, people with big noses in dry environment etc.

    Lets look at the numbers again.

    We start with 1 cell in good conditions.

    In one year we have 5.6 10^109 cells potentially, or more realistically a much smaller but still very very huge number.

    Mutations are common, but only 1 in 1 million is advantageous. This still leaves a huge huge number with advantageous mutations 5.6 x 10^103.

    The ones with advantages either shares it with their peers, or replaces them in a few months, leaving you with the same huge population, but more advanced cells.

    Repeat this process for a few million years, until another lucky accident leads to the next step, be it either photosynthesis, oxygen metabolism or multi-cellular organisms.

    Again, the numbers above are not realistic, as 10^109 organisms would weight many times more than the earth itself, but it should give you a feel for how many opportunities life has for improving itself, and how large the opportunities for evolution to occur really are.

    Surur
  2. #602  
    Quote Originally Posted by shopharim View Post
    ...........From the today view, I don't get why equilibrium seems to have set in amongst the higher complex beings. Within humanity alone we currently have 6 billion uniquely identifable variations virtually of which only .0000000x% are reproductively isolated. And we have been like this for the past 6000 years
    Without granting that "we have been like this for the past 6000 years,"
    I would point out to you that in cosmological time, the period of human history is but the blink of an eye. One would not expect to see much change in such a period.

    In talking about his timeline, Kurzweil points out that the granularity of the clock is a function of how much is going on. He is quick to acknowledge that a lot has been going on for the last 6000 years and he asserts that the rate of change is speeding up. He would note, for example, that life span has doubled in the last 150 years. When does a change in quantity make a change in kind. Look at his projection for the next 100 years, what he calls "evolution by other (technological) means.
    Last edited by whmurray; 05/25/2007 at 12:57 PM.
  3. backbeat's Avatar
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    #603  
    A bit of observation which has certainly shown itself to have legs, given the past 10 years of hard-right-wing congressional/Lobbyist rule.

    Excerpt:

    Darwinism is on the way out. At least, that's what Irving Kristol announced to a gathering at the American Enterprise Institute in Washington not long ago. Darwinian evolution, according to the godfather of neoconservatism, "is really no longer accepted so easily by [many] biologists and scientists." Why? Because, Kristol explained, scientifically minded Darwin doubters are once again focusing on "the old-fashioned argument from design." That is to say, life in all its apparently ordered complexity cannot be understood in terms of chance mutation and the competition for survival. There must, after all, be a designer. So, exit Darwin; enter--or re-enter--God.

    http://www.reason.com/news/show/30329.html
  4. #604  
    Quote Originally Posted by surur View Post
    I see the odds issue is still holding you back.....Surur
    In the simplest terms, yes.

    I guest I'm trying to get my mind wrapped around the numbers. Let's take the example of 5.6 x 10^103 "advantaged" cells in year 1.

    Are we talking the "same" advantage in each? I presume no.
    Are we talking 5600000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 0000 different mutations? I presume no.

    So, that leaves us somewhere in the middle.

    But, now if we have some number of varieties, the competition for resources has now begun. Presumably, the rate of survival for the "disadvantaged" is declining rapidly.

    In all this we're still talking about mostly single-celled entities (a few--56000000000000000000000000000000--of which are multi-celled).

    How many cells do loci have?

    How many cells Do fruitflies have?

    How many cells do frogs tadpoles have?

    How many cells do canaries have?

    .......

    On a different tangent. Time to replicate is a single facet of reproduction. Another facet is lifespan. What if it takes a day to replicate, but most of the single-celled entities only lived 1/2 day?

    Granted, only 1 cell needs to replicate to get the process going. However, if the same survival rates applied in each generation, we are no longer talking exponential growth.
  5. #605  
    Quote Originally Posted by whmurray View Post
    Without granting that "we have been like this for the past 6000 years,"
    Quote Originally Posted by whmurray View Post
    I would point out to you that in cosmological time, the period of human history is but the blink of an eye.
    Understood
    Quote Originally Posted by whmurray View Post

    In talking about his timeline, Kurzweil points out that the granularity of the clock is a function of how much is going on. He is quick to acknowledge that a lot has been going on for the last 6000 years and that the rate of change is speeding up. He would note, for example, that life span has doubled in the last 150 years. When does a change in quantity make a change in kind. Look at his projection for the next 100 years, what he calls "evolution by other (technological) means.
    I was intrigued with the "definition" of life being interpreted as ability to assimilate information--paving the way for that which we currently call "mechanical" to be seen as intelligent life.

    It would seem that biological life as we know it would soon be severely "disadvantaged"

    Hence, I suppose, the comment that humanity is not the goal of evolution.
  6. #606  
    Quote Originally Posted by shopharim View Post
    In the simplest terms, yes.

    I guest I'm trying to get my mind wrapped around the numbers. Let's take the example of 5.6 x 10^103 "advantaged" cells in year 1.

    Are we talking the "same" advantage in each? I presume no.
    Are we talking 5600000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 0000 different mutations? I presume no.

    So, that leaves us somewhere in the middle.

    But, now if we have some number of varieties, the competition for resources has now begun. Presumably, the rate of survival for the "disadvantaged" is declining rapidly.
    So these cells with their small improvements continue to compete, and the better cells survive, replacing the less improved once.


    In all this we're still talking about mostly single-celled entities (a few--56000000000000000000000000000000--of which are multi-celled).

    How many cells do loci have?

    How many cells Do fruitflies have?

    How many cells do frogs tadpoles have?

    How many cells do canaries have?
    In this environment we would only have primitive single-cell organisms.

    On a different tangent. Time to replicate is a single facet of reproduction. Another facet is lifespan. What if it takes a day to replicate, but most of the single-celled entities only lived 1/2 day?

    Granted, only 1 cell needs to replicate to get the process going. However, if the same survival rates applied in each generation, we are no longer talking exponential growth.
    Unless the reproduction rate is less than the replacement rate its still exponential. Why dont you plug in numbers you yourself consider realistic, and see what you come up with.

    Surur
  7. #607  
    I won't jump in too much, because people have been doing a pretty good job.

    -edited out-

    Chris
  8. #608  
    I'm not a biologist. In fact, my academic specialty is Probability Theory. Shopharim, when you consider the liklihoods of various mutations, please consider the following:
    • While mutations may be rare, they have lots of opportunity to occur in large populations. Not quite the same, but if you think of your odds of winning the lottery, they are small. The odds that somebody will win is much better.
    • Mutations are not so rare that they are infinitesimal. Sadly, we should consider the ailments we hear about which are caused by genetic weaknesses. There are many of them and they afflict a great many people. Surely, there are even larger numbers of "mutations" which go by unnoticed because they don't manifest in any significant way.
    • How long has it taken humankind to breed the many, many varieties of dogs we all know? Probably in the, what, hundreds of years? Probably not much more than a thousand. Perhaps the human "pressure" that was asserted on the species was higher than what nature applies, but nature has had an awful lot more time to do it as well.

    As an aside, I'll mention that the lay person tends to have a very skewed perception of what is probabilistically "likely". I've seen many, many examples of this in my academic life. When you ask, for example, what is the likelihood of any two children in a class of 30 sharing the same birthday (month/day), most people would consider it remote, what with there being 365 days in a year and only 30 of them being covered by the class birthdays. However, the answer is actually better than even odds. Don't know about you, but I was surprised when I first learned this, and I was already quite far along in my academic training.
  9. #609  
    Quote Originally Posted by shopharim View Post
    Seriously, given the human population of the earth, why are we so "stable"?
    I'd probably pick two big reasons: 1) very little pressure to select for different traits, and 2) very little isolation to differentiate species.
    ‎"Is that suck and salvage the Kevin Costner method?" - Chris Matthews on Hardball, July 6, 2010. Wonder if he's talking about his oil device or his movie career...
  10. #610  
    Quote Originally Posted by surur View Post
    So these cells with their small improvements continue to compete, and the better cells survive, replacing the less improved once.
    Cool. I got one conclusion right
    Quote Originally Posted by surur View Post
    In this environment we would only have primitive single-cell organisms.
    I realized after posting that I did not make the connection that was intended. In short, I'm looking for the migration from variation within the population, to emegence of significantly different species (i.e. not just reporoductive isolation, but the migration from loci to fruitfly to tadpole to canary...
    Quote Originally Posted by surur View Post
    Unless the reproduction rate is less than the replacement rate its still exponential.
    With mostly 1/2 day survival and 1 day replication, the replacement rate could likely be greater than the reproductive rate.
    Quote Originally Posted by surur View Post
    Why dont you plug in numbers you yourself consider realistic, and see what you come up with.

    Surur
    That's part of my problem. I'm not sure what would be "realistic." (BTW, I'm still digesting the article you posted. So my concerns may be in there)
  11. #611  
    Quote Originally Posted by backbeat View Post
    A bit of observation which has certainly shown itself to have legs, given the past 10 years of hard-right-wing congressional/Lobbyist rule.

    Excerpt:
    Mr. Kristol is quoted in July 1997. His prediction has a few more weeks to be fulfilled. We shall see how strong the legs are.
  12. #612  
    To give you an idea of the scale of life on Earth, all the massive limestone deposits on earth (including those impressive white cliffs of Dover) consist of the trillions of shells deposited over millions of years. Life has been around for a long long time in huge huge numbers.

    I realized after posting that I did not make the connection that was intended. In short, I'm looking for the migration from variation within the population, to emegence of significantly different species (i.e. not just reporoductive isolation, but the migration from loci to fruitfly to tadpole to canary...
    One step at a time. The step from single cell organisms to tadpoles is very big.

    Surur
  13. backbeat's Avatar
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    #613  
    Quote Originally Posted by whmurray View Post
    Mr. Kristol is quoted in July 1997. His prediction has a few more weeks to be fulfilled. We shall see how strong the legs are.
    I never said any prognostication from Krystol had legs, only that a sober reexamination of their agenda against science has legs, showing Neocons and their thinly-veiled, war-drumming apologists for what they are.
  14. #614  
    Quote Originally Posted by whmurray View Post
    ...None of us will be safe until our grandchildren and their grandchildren are the same grandchildren.
    You do realize of course this means somebody's belief system must be destroyed. I trust you are content to seek the destruction of my belief system only through rhetorical means.
  15. backbeat's Avatar
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    #615  
    Quote Originally Posted by shopharim View Post
    You do realize of course this means somebody's belief system must be destroyed. I trust you are content to seek the destruction of my belief system only through rhetorical means.
  16. #616  
    Quote Originally Posted by PatrickS View Post
    I'm not a biologist. In fact, my academic specialty is Probability Theory.
    it looks like you're just the guy I'm looking for.
    Quote Originally Posted by PatrickS View Post
    Shopharim, when you consider the liklihoods of various mutations, please consider the following:
    • While mutations may be rare, they have lots of opportunity to occur in large populations. Not quite the same, but if you think of your odds of winning the lottery, they are small. The odds that somebody will win is much better.
    • It seems in the subject area, we also have to factor in the fact that their offspring will win as well. That mutations occur is fine. But, to get from loci to tadpole (a biiiiiiiiiiiiiiiiiiiiiiiiiiiiig leap though it maybe), we are talking about the compounding of mutations within limited hereditary bandwidth
      Quote Originally Posted by PatrickS View Post
    • Mutations are not so rare that they are infinitesimal. Sadly, we should consider the ailments we hear about which are caused by genetic weaknesses. There are many of them and they afflict a great many people. Surely, there are even larger numbers of "mutations" which go by unnoticed because they don't manifest in any significant way.
    Indeed
    Quote Originally Posted by PatrickS View Post
  17. How long has it taken humankind to breed the many, many varieties of dogs we all know? Probably in the, what, hundreds of years? Probably not much more than a thousand. Perhaps the human "pressure" that was asserted on the species was higher than what nature applies, but nature has had an awful lot more time to do it as well.
  18. Nature has had more time, but has not had intent such as is present in dog breeding. Is "pressure" as forceful as intent?
    Quote Originally Posted by PatrickS View Post
    As an aside, I'll mention that the lay person tends to have a very skewed perception of what is probabilistically "likely". I've seen many, many examples of this in my academic life. When you ask, for example, what is the likelihood of any two children in a class of 30 sharing the same birthday (month/day), most people would consider it remote, what with there being 365 days in a year and only 30 of them being covered by the class birthdays. However, the answer is actually better than even odds. Don't know about you, but I was surprised when I first learned this, and I was already quite far along in my academic training.
    I like the example. What factors contribute to the better odds? My guess is the likelihood can be higher given that the "control" population would tend to have more things in common with each other than would a randomly selected group of 30 people.
  19. #617  
    Quote Originally Posted by backbeat View Post
    A bit of observation which has certainly shown itself to have legs, given the past 10 years of hard-right-wing congressional/Lobbyist rule.
    Excerpt:
    The quote attributed to Irving Kristol is from a survey article by Ronald Bailey that appeared in Reason, July 1997. Incidentally, Bailey did not cite Kristol because he agreed with him so much as because he believed Kristol to be cynical and manipulative. I recommend the article to those who are participating in this thread. While it has a bias, it does an objective job of recapping the criticism of Evolution.

    Among the many interesting observations by Bailey is that, "Ironically, today many modern conservatives fervently agree with Karl Marx that religion is "the opium of the people"; they add a heartfelt, "Thank God!" This is one of several suggestions in the article of an answer to Clulup's question, that the conservative elite believes that, without regard to any truth in the matter, acceptance by the vulgar of God and religion is essential to the preservation of any semblance of civilization. We need the Fear of God to keep the vulgar in line. In the absence of revelation, scripture, and tradition, we would have to invent God out of whole cloth.

    Ten years later, I would argue that not only is this strategy not working but that it is making the problem worse. If civilization fails, it will be the result of the theist's fear of, not to say, hatred for, his theist neighbors.
  20. #618  
    To answer your question regarding "intent" and pressure - they are the same, and intent CAN be as forceful as pressure.

    Evolutionary pressure is simply an increased reproductive advantage gained by some organisms in a population. Remember, one of the tenents of evolution is that it works with what we have. That is, there is natrual variation in the population, and evolutionary pressure works with the variation that exists. One on natural variant has greater reproductive success, they will produce more offspring, be more prevalent in the next generation, and (assuming they continue to have an advantage) will eventually replace the less competative "model".

    Modelling shows that even a SLIGHT reproductive advantage can result in large scale changes relatively quickly (relatively being the key word - we are talking generation times spans, not individual life spans).

    In terms of asking is "pressure" can be as forceful as intent - yes it can. Imagine if some change in habitat and environment meant that suddenly all green lizards were easy to see and easilly picked off by birds looking for food. Suddenly, any lizards with a different color would have a HUGE advtanage, almost to the same degree as if we were ONLY allowing the non-green lizards to mate.

    It can be as strong, but usually isn't.
  21. #619  
    Quote Originally Posted by shopharim View Post
    Indeed, nature has had more time, but has not had intent such as is present in dog breeding. Is "pressure" as forceful as intent?
    The pressure is inherent in the challenge to survive and multiply in the face of competition for resources.

    Re the Birthday paradox, here's a good read. Its actually inherent in the numbers.
    http://www.getsmarter.org/mstv/R3_a.cfm

    Surur
  22. #620  
    Quote Originally Posted by whmurray View Post
    The quote attributed to Irving Kristol is from a survey article by Ronald Bailey that appeared in Reason, July 1997. Incidentally, Bailey did not cite Kristol because he agreed with him so much as because he believed Kristol to be cynical and manipulative. I recommend the article to those who are participating in this thread. While it has a bias, it does an objective job of recapping the criticism of Evolution....
    The article

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