What evidence is there for evolution being non-random?

[cyborg]

Once a mutation arises in a population, the best way of calculating how likely it is to sread, is probabilistically.

Do you or do you not get that your ability or not to make a prediction for some system does not affect how it operates?

It has already been demonstrated that it is entirely possible to produce deterministic systems which have hard to predict behaviour.

So I say again: is everything that happens from the start to the end of a football game inconsequential? Can you explain why we do not use a random number generator to assign the winning outcome?

 

[Dumbledore]

While I might be in definite danger of not being educated enough to post in this thread, yes I did not read the 59 pages of the thread. I think that I understand your arguments perfectly well, did you understand mine! My point again is that evolution in its complexity goes far beyond simple explaination in a few paragraphs and might require significant education to fully comprehend. I understand your argument that evolution can be modeled as a specific kind of stochastic process. My question then is, is why don't the majority of evolutionary scientists view evolution as such a process? Or are you simply the misunderstood genius of our time?

 

[Meadmaker]

So I say again: is everything that happens from the start to the end of a football game inconsequential? Can you explain why we do not use a random number generator to assign the winning outcome?

I think evolution is every bit as deterministic as a football game.

I'll take the platypus, and three points.

 

[Meadmaker]

My question then is, is why don't the majority of evolutionary scientists view evolution as such a process? Or are you simply the misunderstood genius of our time?

Mijo,
I think this is a pretty good question, actually. My answer is buried in the 59 pages of the thread, but I think it's a good question.


My answer:

It depends on what aspect of evolution you are studying. It's not unless you are actually trying to model evolution, as through a simulation, that the random element really becomes important. If you're talking about general trends, you don't need it.

 

[articulett]

While I might be in definite danger of not being educated enough to post in this thread, yes I did not read the 59 pages of the thread. I think that I understand your arguments perfectly well, did you understand mine! My point again is that evolution in its complexity goes far beyond simple explaination in a few paragraphs and might require significant education to fully comprehend. I understand your argument that evolution can be modeled as a specific kind of stochastic process. My question then is, is why don't the majority of evolutionary scientists view evolution as such a process? Or are you simply the misunderstood genius of our time?

I think many people have weighed in to say that it really isn't a simple process and that random is too ambiguous of a term to use to define evolution. Usually, it's the changes in the genome that are modeled with stochastic models... you can also use algorithms and hypotheticals to determine how long it would take to incorporate a mutation giving a 1 percent survival/reproductive advantage into the population given dominant or recessive mutation.

But that wasn't Mijo's question. I don't pretend that I am a misunderstood genius. I am quoting the actual geniuses in the field-- I do teach evolution to students, but my teachers have taught millions... and so it's their words I have used. If anybody wants to understand what is "non-random" about evolution, they need to understand natural selection. Nobody with any credibility calls natural selection random. Moreover you don't describe what natural selection is or the the non-random aspects of evolution by using fuzzy terms and "anything related to a probability". If you want to understand the concept, you have to use the terms the way the scientists are using them in the peer reviewed papers.

My credibility isn't at question. I understand the concept... I teach it to others... I converse with Dawkins. I read and understand peer reviewed topics on the subject. I pass boards on the subject. And so I will repeat for you and the others certain you know something that you truly do not:

No peer reviewed scientist is using Mijo's definition of random (anything related to probability)... moreover, nobody uses stochastic as a synonym for random. Moreover, nobody calls a process random just because some parts of it may be random. No peer reviewed paper says "evolution IS random" nor "natural selection is random" nor that "natural selection is best modeled as a stochastic process". If you guys think it makes sense... go submit something for peer review. It's a peer reviewed paper that said natural selection is NOT random... it is the foremost expert on evolutionary biology who says that natural selection is not random. It's Talk Origins that says those who call evolution random don't understand natural selection. It's Berkeley edu. and a slew of expert forum members and very intelligent people who have dropped by this forum to say that information change on the genome level is relatively random, but selection is determined (biased, non-random, oriented, ordered, the de-randomizer.) If you have a lame definition that is indistinguishable from an inept liars definition (Behe), you've got a definition that is only useful in your head.

Telling people that selection is probabilistic is so vague and misleading that you are unlikely to convey why the male butterflies all have the new mutation. Did they know? Was it designed? How did they all get so lucky? Answer: Natural selection gives the appearance of design... we just see the ones who got to live and pass on more of whatever genes aided in their eventual reproductive success. It only had to happen one time... and the rest are descendants of that one time.

Instead of insulting those who might actually educate you as to what the non-random aspects of evolution are and why biologists go out of their way to show how this non-randomness gives the appearance of design-- you ought to try reading a book. The Selfish Gene is good. Or just read the quick peer reviewed article I linked. Or watch the Dawkins clip. And if you still don't understand... it's probably too late. You are too overconfident in your wrongness and have lost the plasticity to understand a basic fairly simple scientific principle. None of those trying to sum up evolution as "random" really wanted an answer to the question in the OP--they thought they already had it. The experts disagree.

I don't care if you think you know how to explain evolution. I care that my students understand it. I care that I understand it. I already know there is a world of people who think they know everything important there is to know about it though they still sum up evolution as random. Behe wrote a book saying pretty much the same nothingness. But it doesn't fly in real science and you guys can't get that BS to fly here either.

 

[jimbob]

Cyborg, my point is that one can model the evolution of specific traits in isolation.

A better colour-camoflage scheme for a moth might affect its predation by birds, but will have no effect on its predation by bats, assuming they use echolocation. Nor will this affect the ability of the moth to find food.

As far as selection for colour-camoflague is concerned, bat predation and food location is "random noise". This makes the selection for a better colour scheme less efficient but does not stop it.

Another measure of this is the selection intensity.

Artifical selection can have a selection intensity approaching 100% as opposed to probably less than 10% for natural selection.

How do you attempt to model the evolution of a trait in isolation, without a probabilistic treatment?

 

[jimbob]

Articulett,

No peer reviewed scientist is using Mijo's definition of random (anything related to probability)... moreover, nobody uses stochastic as a synonym for random. Moreover, nobody calls a process random just because some parts of it may be random.

The reason for this is because that definition of stochastic wrt. random has passed into school-level text books (in the UK). There is no debate about it. Dawkin's treatment is implicit, because to any numerate person, there is no need to make the treatment explicit.

What else does a "selective advantage as little as 1:1000" mean if not part of a probabilistic treatment?

 

[Dumbledore]

Well articulett you certainly come off as the certain guardian of the truth. I am wondering if you actually read my post. Not being an expert I never asserted that I knew if evolution is a stochastic process or not, in fact I asserted the opposite. The mainstream definition of evolution does not state that evolution is a stochastic process so I asked why this is so. I would hope that this would indicate to my fellow post readers that I am not an expert but instead I am asking an elementary question. Beside your condescension and frequent insults in which you criticized me for being insulting I found you post very illuminating. I enjoy reading this thread, though not all 59 pages of it, to learn more about this debate. Now back to the argument, natural selection certainly seems not to be a probabilistic process, excuses me for not using proper terminology but I am an non-expert after all, but probabilities certainly seem to play a part in it. I think this where the confusion comes in, if probability plays such a large role in evolution then why isn't evolution a probabilistic theory? If I may so humbly ask the experts such a wrong footed question.

 

[cyborg]

Cyborg, my point is that one can model the evolution of specific traits in isolation.

Yes, I've never argued anything else. Using probabilities is a good choice when it would be too computationally intensive to take all other variables into account.

How do you attempt to model the evolution of a trait in isolation, without a probabilistic treatment?

You don't because doing so would be intractable. But as I've been pointing out the model is not reality.

 

[articulett]

Articulett,

The reason for this is because that definition of stochastic wrt. random has passed into school-level text books (in the UK). There is no debate about it. Dawkin's treatment is implicit, because to any numerate person, there is no need to make the treatment explicit.

What else does a "selective advantage as little as 1:1000" mean if not part of a probabilistic treatment?

But that wasn't the question. Dawkins also says "natural selection is the opposite of random"... the question was about how evolution is not random, correct? It wasn't about probabilities or a definition of random that was so loose that it could be applied to anything related to probabilities in any way. You're not "wrong"--you're just not answering the question and not conveying how the order comes about.

 

[articulett]

Well articulett you certainly come off as the certain guardian of the truth. I am wondering if you actually read my post. Not being an expert I never asserted that I knew if evolution is a stochastic process or not, in fact I asserted the opposite. The mainstream definition of evolution does not state that evolution is a stochastic process so I asked why this is so. I would hope that this would indicate to my fellow post readers that I am not an expert but instead I am asking an elementary question. Beside your condescension and frequent insults in which you criticized me for being insulting I found you post very illuminating. I enjoy reading this thread, though not all 59 pages of it, to learn more about this debate. Now back to the argument, natural selection certainly seems not to be a probabilistic process, excuses me for not using proper terminology but I am an non-expert after all, but probabilities certainly seem to play a part in it. I think this where the confusion comes in, if probability plays such a large role in evolution then why isn't evolution a probabilistic theory? If I may so humbly ask the experts such a wrong footed question.

I'm sorry... but I think you started it... or maybe I was sensitive when you agreed with cyborg who was being sarcastic.

Probabilities are important... but the question was about the non-random aspects of evolution. How do things look designed... it's not just large numbers and collisions of randomness--it's not just physics-- it's natural selection-- the stuff that makes the best replicators gets copied widely into genomes, the stuff that is detrimental is weeded out--often long before anyone knows "it" exists. Mutation may be a blind tinkerer but natural selection chooses the products that make future products. The randomness and the probability are easy to understand. It's the easy part of Poker too... but it's how the game is played...what strategies beget better strategists that matter to the result.

http://www.msnbc.msn.com/id/19733274/

In the above link... what part of the result was NOT RANDOM? The beneficial mutation was "random"-- And though it looks like the butterflies somehow knew to evolve protection... that is not what actually happened. Natural selection ensured that only those who happened to have the lucky mutation (the first through de novo--the rest through inheritance) survived. There's no need to confuse this simple concept-- this simple understanding --by interjecting terms like "random" and "probability". It doesn't answer the question to do so. But Mijo doesn't want the question answered. He wants to believe he has the answer... and the answer is "evolution IS random". To him it is. But it isn't to any biologist. We don't know how many millions of butterflies died during the endless march of time--we just know that one combination worked. And the recovery of the butterflies at this time is due to the progeny of that lucky mutant.

Not every process that contains randomness IS a random process. In fact, "random process" is a misnomer for stochastic processes which are processes that contain randomness, but they are not considered random themselves. The word process implies increments or steps or direction... these are not things associated with the word random. If you want to be specific... random is a singular where all possible probabilities are considered relatively equal. A loaded dice is not considered "random"--except by mijo's definition it would be.

 

[Dumbledore]

Thanks articulett that was very clear and straight forward, I do believe I have a better understanding of the discussion now. You also answered my question of why the mainstream definition of evolution does not define it as a stochastic process. As far as mijo not wanting to hear the answer to his question I can empathize, there seems to be at least a handful of posters in the forum who seem to be quite deaf to answers to their questions. Again thanks!

 

[mijopaalmc]

Thanks articulett that was very clear and straight forward, I do believe I have a better understanding of the discussion now. You also answered my question of why the mainstream definition of evolution does not define it as a stochastic process. As far as mijo not wanting to hear the answer to his question I can empathize, there seems to be at least a handful of posters in the forum who seem to be quite deaf to answers to their questions. Again thanks!

I'm sorry, but this is utterly laughable. articulett has displayed on numerous occasions that she doesn't understand the slightest thing about probability and statistics and keeps repaeting the same straw men over and over again. For instance, my definition of "random", which is the definition of "random" used in probability theory, contrary to what aritculett insists, does not make everything random. Furthermore a stochstaic process is not merely a process that contains random elements; it process that is defined by random ness and probability.

Until you understand these things, Dumbledore, I suggest you regrain from agreeing with articulett.

 

[articulett]

Thanks articulett that was very clear and straight forward, I do believe I have a better understanding of the discussion now. You also answered my question of why the mainstream definition of evolution does not define it as a stochastic process. As far as mijo not wanting to hear the answer to his question I can empathize, there seems to be at least a handful of posters in the forum who seem to be quite deaf to answers to their questions. Again thanks!

You're welcome. I'm sorry about the misunderstanding. There is a document by the main proponents of intelligent design called the "wedge strategy"... and part of their strategy is just to confuse understanding of evolution by saying scientists think all this complexity arose randomly-- like a tornado going through a junkyard creating a 747. So biologists have to go out of their way to show why it's not random like that strawman at all. Such "randomness" sounds "impossible"--and it probably is. So that makes a designer look necessary.

And there is a designer of sorts--natural selection-- but it's blind.
Just like you and everyone else who participates in the internet is part of the "design process" though no one is in charge over all. Complexity can and does occur from the bottom all the time once you have a selection process in place that weeds out the fittest (and by fittest I just mean the ones that are most likely to get copied and or built upon). You don't need to know how to make babies to make lots of them... you just have to survive and have urges that facilitate the process... evolution is "directed" by the organisms that contain the info. that does this the best.

 

[sphenisc]

random definition
adj.
1. Having no specific pattern, purpose, or objective: random movements. See Synonyms at chance.
2. Mathematics & Statistics Of or relating to a type of circumstance or event that is described by a probability distribution.
3. Of or relating to an event in which all outcomes are equally likely, as in the testing of a blood sample for the presence of a substance.

From the second definition it's apparent that "random" applies to the description of a circumstance or event, not to the event itself. It is a description of the description of an event.
Likewise a process is a random process if the description of it contains radom elements, if the description doesn't, then it isn't. Thus the same process can be random or non-random depending upon the description used. This, I think, is part of the confusion here.

I can describe rolling a die as "it comes up 6", or "it comes up 6 with probability 1/6". The first treats(describes) the process as non-random, the
second as random. Now for most purposes the second description is preferable, it accurately describes the results of a large number of trials, while being less precise about the results of any one trial.

{The rest of my post seems to have disappeared - it basically said that it comes down to the preferred choice of description and that depends on the the purpose for which it is used - sometimes a compromise has to been drawn between describing a process accurately, i.e being almost always right; being precise, i.e narrowing down the range of possible predictions, and complexity, i.e. extra accuracy/precision may not be worth the effort.]

 

[Dumbledore]

I'm sorry, but this is utterly laughable. articulett has displayed on numerous occasions that she doesn't understand the slightest thing about probability and statistics and keeps repaeting the same straw men over and over again. For instance, my definition of "random", which is the definition of "random" used in probability theory, contrary to what aritculett insists, does not make everything random. Furthermore a stochstaic process is not merely a process that contains random elements; it process that is defined by random ness and probability.

Until you understand these things, Dumbledore, I suggest you regrain from agreeing with articulett.

Thanks for telling me who I should agree with or not, and that I don't know enough to do so!! Though I probably don't enough to ask this question again I will recklessly ask you again. Why does the mainstream definition of evolution not regard it as a stochastic process?

 

[Walter Wayne]

Why does the mainstream definition of evolution not regard it as a stochastic process?

If you look at literature on evolution, it is laced with references to probabilities as opposed to certains. We read passages that state an individual has a "greater chance" to pass on his genes, or is "more likely" to reproduce and many other such phrases. However, the literature rarely if ever uses the term random or stochastic. This is odd in that there is nothing in the description of evolution that would lead one to believe it is anything other than random.

Why the literature doesn't use the term stochastic, I am not sure. Part of it may be the amount of teaching of stochastics in undergraduate biology or the nature of the teaching. Part of it may be the political nature in the current science vs. religion confrontation.

Walt

 

[articulett]

We don't use such definitions because creationists use such definitions to promote the notion that scientists think all this "complexity" arose through random chance. No biologist thinks that. The appearance of design is due to natural selection--not randomness. Everyone can understand the random part...even Mijo and Behe-- but creationists and know it alls think they understand natural selection but only seem to be able to "see" the probability aspects--they are unable to describe the non-random aspects, the incremental aspects, or why it looks designed. Those who have a vested need to sum up evolution as random are either creationists or people who do not understand natural selection. At least that is what Talk Origins says.

This thread is evidence-- I concur.

 

[Walter Wayne]

I earlier stated ...

Why the literature doesn't use the term stochastic, I am not sure. Part of it may be the amount of teaching of stochastics in undergraduate biology or the nature of the teaching. Part of it may be the political nature in the current science vs. religion confrontation.

Now I know that using one case is insufficient to make a general statement but ...

If you look at the post that followed mine, articulett immediately mentions that one of the reasons is "because creationists use such definitions to promote the notion that scientists think all this "complexity" arose through random chance." That would be the political nature.

As for the quality of education biologists get, earlier in the thread articuleet stated

The top two definitions of random in my Science dictionary refer to it as not being connected to the past or future and/or having equal (not necessarily uniform) probability. When random events are added up to make patterns, that is a stochastic process. True randomness in the mathematical sense probably doesn't exist in the real world--but mutation and recombination is pretty close to random. Evolution is not random because it relies entirely on the past and is the stepping stone towards the future. Each "step" alters the probabilities in the next "step"...

Now one definition is having equal probability. However, the quintessential randomness in physics, that in wave-function of fundamental particles, is most definitely not equal probability. In fact, very few random processes are equal probability. Nobody versed in stochastics would use this as a definition.

Another definition given is "not being connected to the past or future". As articulett states, 'Each "step" alters the probabilities in the next "step".' Now if one random event influences another, this does not make the events non-random, what it means is that the "steps" are statistical dependent on eachother. So again the science dictionary seems to be a pretty poor source for definitions of random.

Statistical independence is not a concept out of reach of the layman either, so this isn't a case of avoiding the term for fear of being overly technical. We know that if we sum two dice we get a random number between 2 and 12. However, if we know that one of the dice came up 4 that the result is between 5 and 10. So the sum of the two dice is not independent of the roll of the first die, the sum is still random though.

And articulett, I don't know why you keep talking about summing up evolution as random. No one here is trying to do that. We are merely stating one characteristic of it. I certainly wouldn't sum up my computer as "digital", but it is indeed one quality it has.

Walt

 

[mijopaalmc]

So what is your evidence that natural selection is non-random?

We all know it is biased towards individuals that can survive better in the environment, bit that doesn't mean that it is non-random. If there is more than one possible out come for each individual (here, survival or death) then the process is based on probability.

The probability might be very close to 1 for either survival or death, as it was in the example with the South Pacific butterflies. However, once the probability of a survival event becomes 1, one creates a monocultural population or a population in which the survival of each singular unique phenotype is not an event.