Epic Fails for Experimental Evolution

As science theories go, evolution is perhaps the least amenable to experimental observation. The processes are presumed to occur over vast periods of time, the cited evidence is often entombed in rock and subject to much speculation, and the proposed mechanisms are resistant to experimentation.

But with modern methods, much of this may be changing. Until recently it was difficult if not impossible to directly observe the changes in populations of organisms as the result of either incidental or introduced genetic modifications. Simply mapping genomes was a costly and expensive proposition, much less conducting regular experiments which tracked genetic changes. But technology is rapidly advancing in this area, and increasingly scientists are able to make more direct observations about the actual effect of genetic changes in populations of organisms, and directly test the claims of neo-Darwinism (the synthesis of Darwin’s theory of evolution with modern genetics). First a little background on why such experiments are relevant to evolution.

In the modern iteration of evolution, genetic variation is thought to be the product of mutations. Those mutations express themselves in the form of physical traits that act to make individual organisms more or less capable of reproducing in their environment, which in turn affects their ability to pass on those traits to their offspring. If the variation in question confers some beneficial trait, over the course of a number of generations the increase reproductive fitness causes the trait to predominate in that population of organisms. Given sufficient modifications over a sufficient amount of time if the organisms with novel traits become a separate interbreeding population, then a new species comes into existence.

Again, because of the time periods involved, and the fact that the changes occur on an unseen genetic level, this process isn’t very amenable to observation or experimentation; however two recent experiments have allowed researchers to directly observe the propagation of genetic changes in a population of organisms, the first tracking a mutation in a population of fruit flies over the course of 600 generations, and the second observing the effect of a introduced mutation on a bacterial population.

The first paper, published in Nature, details a 30 year experiment observing a selection process acting on the genome of a population of fruit flies. In this case they were chronicling the how a particular adaptation moved through a population – specifically a trait that conferred accelerated development. Fruit flies mate as soon as they mature, so accelerated development (estimated to be 20% faster) would certainly convey a reproductive advantage to individuals with the trait; in fact, the evolutionary expectation is that eventually the trait would ‘sweep’ the population and become fixed in the population. And this would be the evolutionary expectation for a significantly advantageous trait.

What they observed when they surveyed the genomic regions to identify the modifications in the selected population was that there was little difference from the control population. Not only had the beneficial genetic modifications not ‘swept’ the selected population – in fact the frequency of the trait was little different than the control population. As the paper concludes:

Our work provides a new perspective on the genetic basis of adaptation. Despite decades of sustained selection in relatively small, sexually reproducing laboratory populations, selection did not lead to the fixation of newly arising unconditionally advantageous alleles. This is notable because in wild populations we expect the strength of natural selection to be less intense and the environment unlikely to remain constant for, 600 generations. Consequently, the probability of fixation in wild populations should be even lower than its likelihood in these experiments. This suggests that selection does not readily expunge genetic variation in sexual populations, a finding which in turn should motivate efforts to discover why this is seemingly the case.

In short, if the activity failed to occur in the lab under optimal conditions, it is unlikely that traits are going to be transmitted this way in nature. If that is so there is a fundamental flaw in the current evolutionary theory.

In the second case researchers inserted mutations in various loci in a genome in order to determine the effect on the fitness of a population of bacteria. As mentioned before, mutations are seen as essential for the production of new information in Neo-Darwinian evolution. This is problematic when such mutations occur on genes, or portions of the genome that sequence for proteins which are critical to the organism as such a mutation could deleterious to the organism’s survival. To get around this, evolutionists have proposed that mutations can occur on non-sequencing portions of the genome, and thus will produce no such effects – those mutations to non-coding sequences could serve as the raw material for novel genetic sequences.

What researchers found in this experiment however was that the introduction of mutations throughout the genome, whether to coding sequences or non-coding sequences was equally the effects were equally negative:

Even more surprising was the fact that mutations that do not change the protein sequence had negative effects similar to those of mutations that led to substitution of amino acids. A possible explanation is that most mutations may have their negative effect by altering mRNA structure, not proteins, as is commonly assumed.

This certainly casts a pall on the notion that there exist portions of the genome that are amenable to random mutations – if introduction of such mutations to any portion of the genome is equally deleterious to an organism, then there is little room for the acquisition of novel traits through incremental addition of such modifications, a process critical to evolutionary advancement.

Much of this research comports with Michael Behe’s thesis in The Edge of Evolution that the significant genetic leaps required to produce complex novel traits simply aren’t observed in nature.

Evolution has been difficult to test up until now –but as so often happens in science technology has caught up with theory; and in this case the current theory of evolution isn’t fairing so well.

Advertisements

16 Responses to Epic Fails for Experimental Evolution

  1. Bettawrekonize says:

    I’ve said this before and I’ll say it again. If evolution really predicts a nested hierarchy, why is it that there is more genetic diversity across races than within a race. Doesn’t it make sense that people within a race will likely be more genetically similar than people of different races if it’s the case that organisms should fall into a nested hierarchy?

  2. Bettawrekonize says:

    errr. sorry, why is it that there is more genetic diversity within a race than across races *

  3. Bettawrekonize says:

    Like I’ve said before, UCD doesn’t predict a nested hierarchy for the simple fact that it’s possible for cousins to share genetic and morphological traits that brothers do not share. A nested hierarchy resists evolutionary explanation. On top of that, the fact that two people of the same race tend to have (on average) fewer genetic similarities with one another than two people of different races makes a nested hierarchy explanation even less feasible.

  4. Bettawrekonize says:

    makes a nested hierarchy outcome *

  5. Bettawrekonize says:

    It would be interesting to see if chimps and apes also share similar characteristics. Are there animals (ie: apes) from different regions that are more genetically similar to one another than to those of the same region? If so, that again would make a nested hierarchy less feasible.

  6. Michael Hawkins says:

    1) Funny how the papers don’t come to creationist conclusions.

    2) The big conclusion for the first paper is that there is a difference in how selection occurs in asexual versus sexual populations. This does not conclude that therefore there is any problem with evolution.

    3) The second paper just concludes that change in shape can happen in a different area and when it does it can be deleterious.

  7. jackhudson says:

    1) Funny how the papers don’t come to creationist conclusions.

    I didn’t say it did. Nor would we expect it to – it simply weakens the case for evolution as it is currently understood and generally agrees with Michael Behe’s thesis. You didn’t address any of this in your response.

    2) The big conclusion for the first paper is that there is a difference in how selection occurs in asexual versus sexual populations. This does not conclude that therefore there is any problem with evolution.

    The result was contrary to what were expected based on evolutionary expectations. The author admits as much. There certainly seems to be a problem with evolution as it has ordinarily been described.

    3) The second paper just concludes that change in shape can happen in a different area and when it does it can be deleterious.

    This sentence doesn’t even make sense Michael, try again.

  8. Bettawrekonize says:

    “1) Funny how the papers don’t come to creationist conclusions.”

    There is a difference between saying that the author(s) don’t come to creationist or ID conclusions and saying that the evidence doesn’t come to such conclusions.

  9. Michael Hawkins says:

    Haha, you aren’t even able to understand what is being said here. It isn’t a surprise you didn’t understand the paper.

    (By the way, when I only cite a paper and not an article, it’s because I’m familiar with the paper, most often by actually reading it. It’s really, really obvious you didn’t read it.)

  10. jackhudson says:

    Are you responding to anyone in particular Michael, or just lashing out?

  11. Michael Hawkins says:

    I’m frequently surprised at how you rarely read things closely. Take a look at the parentheses. Who here only cited a paper and not an article? It was either you or Betta. Since Betta is only responding to the post, and since your post cites only the paper and not a separate article on the paper, it seems that I must be talking to you. But looking at the evidence is a weak point for you.

    Please go back and actually read the paper. Even with only a few semesters of 20 year old biology courses under your belt you ought to be able to understand several parts of what the authors are saying.

  12. jackhudson says:

    Michael, I have more science education under my belt than yourself, a bank teller who has yet to complete his undergraduate work. I have read considerably more science publications than yourself, and this particular issue is one I have been involved with since (again) before you were born. If you have something substantive to say here, than say it – ad homs don’t cut it here.

    Why you think your lack of experience and education is somehow advantageous, I have no idea.

  13. Michael Hawkins says:

    That I am working towards a double major with at least two minors, have virtually all my biology courses under my belt, am not old and pudgy, and have specific training in how to read and interpret scientific papers gives me good ammunition for this pissing contest in which you have been implicitly begging me to compete with you, but I’m not interested in any further golden showering with you.

    You can try and go for the jabs all you want, but you and I both know you did not read that paper. It’s still really, really obvious.

  14. jackhudson says:

    Michael, you are a young undergraduate who works as a teller in a bank whio has been considering these issues for a few years, and who is completely myopic when it comes to discussing them. I don’t fault you for your youth and lack of experience and knowledge because those things don’t matter to me, I only care about a reasoned civil conversation on important subjects. Unlike you I don’t care about people’s appearance, or background or age. That you hate people different from you in this regard is quite sad actually.

    But you have not even dicussed the details of this paper much less answered any of my claims. Yelling ‘creationist!’ like some possessed victim of an atheist body-snatcher does not constitute a reasoned scientific response.

  15. Michael Hawkins says:

    Stop lying. You’re throwing out ad hominen attacks, focusing on my age and my job (because I should be ashamed that I have a regular full-time job while going to school as a full-time student?), and you’re citing my position in education constantly. I honestly don’t think you’re terribly intelligent, but I also don’t think you’re stupid enough to actually think you’re telling the truth.

    As for the paper, I have an entire post on it which is a pingback in this very comment section.

  16. jackhudson says:

    I think it’s good that you found some work as a bank teller; why you think that is an ad hom (or lying?), I have no idea. We need bank tellers, though I do most of my banking online. I think you should be proud of your efforts as a student, and keep up the studies – perhaps you will find a career in your field someday. I do have to warn you, finding a job these days in any field can be difficult, especially when you have left a track record of attacking private citizens on the web expressing hate for people based on their age, appearance, and chosen faith. Those are big no-nos in most places. I am sure you will explain it all in your interviews though.

    And as you know, I don’t comment on your site which consists mainly of you and Bob saying “Christians evil, atheists good”.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: