Natural selection

[Wowbagger]

You can use fluid dynamics to better understand a crowd exiting a building but that doesn't mean the crowd will always act like a fluid.

Listen to yourself. That is a self-refuting argument.

If fluid-dynamics really are useful in predicting aspects of crowd behavior (an interesting concept!), then how is that supposed to prove that they are not effected by fluid-dynamics?! I still don't get it.

Maybe fluid-dynamics is not useful to describe humans, all the time. In that case, the concept has limits in applicability.

In the case of evolution, we admit that genes are not the only game. They may work as units of selection in the biological bodies, but to describe changes in societies and tools, over time, you need to add other ingredients: Memes or whatever. It is still Darwinian-like evolution, in the end, anyway.

Keep in mind: Darwinian Evolution focuses on adaptive changes over time. Though, evolution, in general, does not. It would be naïve to assume all changes are adaptive.

Darwinism, thus, may have some limits in applicability: The origin of life, for example (no units of selection, or primitive ones, to work with). However, the origin of life could still be described with more general evolutionary terms. And, that is how metabolism-first ideas are being developed (RNA-World ideas, on the other hand, are more Darwinian).

Evolution, in general, may yet have limits in applicability, in regards to life forms*, but it seems we have not found them, yet.

(* No comment, yet, on cosmological evolutionary theory)

They aren't. The fact that humans developed a tool to improve design, based on the principles of evolution, doesn't mean that the planes are subjected to evolution.

Let me rephrase what I said: If airplanes evolve, then how could evolution not apply to them?

Not necessarily. Some monasteries place themselves in quasi-total isolation.

How do you know they were really celibate?

All kidding aside: I am not an expert on monasteries, but I do believe they were put to various uses: Winemaking, book copying, faith-related tasks (even if these turned out to be useless), training for medical services, etc.

Explain me the soviet revolution, the vietnam war and the fall of berlin wall using evolution.

I might have to start a new thread, for these challenges. I am not an expert on any of those particular examples, myself.

I know that, in general, war has its roots in resource competition, with genes being selected for that help kin identify themselves from outsiders; which were later adapted to characteristics that distinguish nationalities from each other, etc.

The point that I'm trying to make is, even if there are paralels between some social phenomena and evolution, you can't apply the darwinian theories to human societies. From the moment that you try to do that, you will have to explain things like class, gender, art, politics and religion in the framework of evolution.

I have read a few books on the subject, as noted in one of my previous posts. There is no reason why we can not gain any insights into any of those things, using evolutionary theory and models.
Perhaps you have not been informed about this, but that is okay. I named some of the books in one of my previous posts. You can peruse some of those, to obtain a better understanding:
http://www.internationalskeptics.com/forums/showthread.php?postid=3534861#post3534861

I would add Breaking the Spell by Daniel Dennett, the works of Steven Pinker, and perhaps a few other books, if I can think of them, to that list. I suspect that the more you look into this, the more will find that most of the top professional scientists have no problem using Evolution to describe any of those fields.

Of course you can say that everything evolves, but when you have an intellect behind that evolution, things change.

I suppose you could try to place Darwinian evolutionary processes into two categories: Natural (no intelligence involved), and artificial (intelligence applied, to some degree). Though, there are huge gray areas between. And, even in artificial selection, the process is never 100%: Artificial selection is nothing more than humans adding their own selection pressures to the otherwise all-natural fitness landscape of life forms.

But, in either case, if describing the process in Darwin-like terms is useful, who are you to doubt the legitimacy?

 

[jimbob]

I'd argue that memetics, whilst an interessting idea shouild not really be confused with evolution because the source of variation is (often) not remotely akin to the random variation that biological evolution has.

For example; until I saw Kleinmann's posts, the idea that he was "a bit of a prat, what" hadn't occured to me. Once I saw what he was posting, it was inevitable, and arose from no process akin to "random variation".

 

[Taffer]

I'd argue that memetics, whilst an interessting idea shouild not really be confused with evolution because the source of variation is (often) not remotely akin to the random variation that biological evolution has.

For example; until I saw Kleinmann's posts, the idea that he was "a bit of a prat, what" hadn't occured to me. Once I saw what he was posting, it was inevitable, and arose from no process akin to "random variation".

This is why one should be careful to distinguish between different forms of evolution. Biological evolution is only one form of evolution, after all.

 

[Megalodon]

If fluid-dynamics really are useful in predicting aspects of crowd behavior (an interesting concept!), then how is that supposed to prove that they are not effected by fluid-dynamics?! I still don't get it.

I think we're talking past each other, and that some of the disagreement is semantic.

What I mean is that fluid dynamics is useful to test if a building has enough exits in case of a chaotic evacuation. This doesn't mean that the crowd will be a fluid, or even behave like one... It will be humans, stampeeding.

Darwinism, thus, may have some limits in applicability: The origin of life, for example (no units of selection, or primitive ones, to work with). However, the origin of life could still be described with more general evolutionary terms. And, that is how metabolism-first ideas are being developed (RNA-World ideas, on the other hand, are more Darwinian).

And here is the crux of the matter. The OP talked about Darwinism, and so did I. Of course anything that changes over time can be consider to evolve, but this would get to the ridiculous of, for instance, Evolutionary Geology. It's silly and redundant, and there is absolutely no need of dragging Darwin into it.

Let me rephrase what I said: If airplanes evolve, then how could evolution not apply to them?

Planes don't evolve. Our notion of what a plane is supposed to look like does.

All kidding aside: I am not an expert on monasteries, but I do believe they were put to various uses: Winemaking, book copying, faith-related tasks (even if these turned out to be useless), training for medical services, etc.

Not all, I believe, and my example is basically of people who devote themselves to a life of ascetism and isolation. Not a very good one, in retrospect... goes with the rest of my disastrous participation in this thread.

I might have to start a new thread, for these challenges. I am not an expert on any of those particular examples, myself.
I know that, in general, war has its roots in resource competition, with genes being selected for that help kin identify themselves from outsiders; which were later adapted to characteristics that distinguish nationalities from each other, etc.

My point is that all of those events (maybe not Vietnam, but I already put it in) were completely unpredictable. They were unpredictable because they were driven by ideologies. We can use evolution to explain them post-facto, but we can equally use social and political sciences. Again, no need to drag Darwin into it...

I suppose you could try to place Darwinian evolutionary processes into two categories: Natural (no intelligence involved), and artificial (intelligence applied, to some degree). Though, there are huge gray areas between. And, even in artificial selection, the process is never 100%: Artificial selection is nothing more than humans adding their own selection pressures to the otherwise all-natural fitness landscape of life forms.

I understand your point, I just don't agree with it. Of course you are right when you say "Artificial selection is nothing more than humans adding their own selection pressures to the otherwise all-natural fitness landscape of life forms", but it doesn't help describe the social and cultural aspects of a particular human society. The biological human is subject to Darwinism, but not the social.

But, in either case, if describing the process in Darwin-like terms is useful, who are you to doubt the legitimacy?

Me? I'm the biggest fish around

 

[jimbob]

This is why one should be careful to distinguish between different forms of evolution. Biological evolution is only one form of evolution, after all.

Indeed, especially when talking about something the "the 'evolution' of the fighter aircraft", which is completely different to Darwinian evolution and is very similar to the mechanism that IDers claim.

That is why I think it is better to use a different word, like "development", as in "the 'development' of the fighter aircraft". Indeed, there are several IDers that do claim this, Dembski for example.

 

[dakotajudo]

Yes, of course you could explain stuff without using evolution. My point was that adding evolution to an explanation helps us discover more about it!

If that was your point, you didn't express it very well. There's a big difference between "any aspect of life can be explained" and "adding ... to an explanation".

You should pick your words more carefully. What exactly do you mean by "explanation". Perhaps you should cite specific examples from the literature to illustrate your point.

We could describe genes in purely Mendelian ways, using terms such as "recessive" and "dominant" characteristics. However, when we apply Evolution by Natural Selection, we can explore precisely why one characteristic is dominant over the other. And, we can then apply that to make more precise predictions in population dynamics, than Mendel alone.

How, exactly, does applying "Evolution by Natural Selection" provide insight into dominance? Again, I don't think you're choosing your words very carefully, so provide an example, please.

You do realize that the majority of cases of dominance can be explained in terms of physiology, molecular biology or biochemistry? Read Kacser and Burns (http://www.genetics.org/cgi/content/abstract/97/3-4/639) .

Now, when you say that we can make more precise predictions in population genetics, what exactly to you mean? Cite an example, please, otherwise I might have to conclude this is something you're making up in your head.

Because, honestly, you've got things a little mixed up. Certainly models of population genetics are used to refine evolutionary theory; and population genetics are also used to study the inheritance patterns of quantitative traits (and, of course, Mendelian traits are just single locus quantitative traits with high penetrance), but do you really mean to argue that evolutionary theory is used to refine models of genetic dominance?

Consider the example of cystic fibrosis. It's a highly penetrant, autosomal recessive disease, that, in spite of being commonly fatal at an early age, persists in the human population. How does Evolution by Natural Selection explain the Mendelian dominance of the cystic fibrosis wild-type gene? (And no fair fudging. I know how the gene was discovered).

Based on evolutionary theory, all that could be said about cystic fibrosis was that it must confer some sort of selective advantage for it to persist in the population (or, maybe, it was linked to some trait that conferred an advantage? Extended haplotype?).

But once the biochemistry of the gene was elucidated, the patterns of inheritance and population genetics of cystic fibrosis just fell into place quite quickly.

That's my example. Do you have a counter example to prove your point?

Scientists are not out to shoehorn evolution into every nook and cranny, for no reason.

No, but you seemed to be.

Remember, I came into this because of your bold statement "I challenge anyone to come up with some aspect of life, that can't be explained by Evolutionary processes". That's over-reaching.

If you would simply stick to the merits of evolutionary theory, such as

They apply evolution to problems, because it is a useful framework for making new discoveries.

and provide specifics, well, I wouldn't be bothered with you.

Because there are plenty of people on the anti-evolutionist side who can and do explain life without using evolutionary processes. And they are much more credible scientists than you are.

So, if you are going to do this - preach the word of evolution - try to learn to do it right.

Let's go back to cystic fibrosis. I can explain the mechanism of disease and the patterns of inheritance and the persistence of the trait within the human population, without relying on evolution processes. What exactly does evolutionary theory add?

(I do know the answer to that, but I'm playing devil's advocate now).

Or, if we're getting to far off topic, how do we address the original posters question, using the theory of evolution? Specifically, not in some general, hand-waving sense.

I think you discovered a new form of fallacy: Argument from What Happens to be On My Bookshelf.

Cute.

For some reason, I get the sense that the paper you linked to supports my arguments, not yours.

No, Megalodon is the one arguing that you can't apply evolutionary theory to culture; I'm telling you that you're making overly broad statements about the application of evolutionary theory to biology. If you want to use it as an excuse to go off on memes, fine, but please, try to pay attention to what I'm saying.

On the other hand, Rogers and Erlich do not use the term "meme", nor does they cite Dawkins. Are you sure it's correct to apply "meme" here? While the word has certainly spread in the popular literature, it's not seen much in research.

It is a usage I have seen many a creationist try to assert, as an argument against Evolution, as if Evolution was really that random.

That's no excuse for downplaying the random components of evolution.

You have to demonstrate, to the same degree Heisenberg did, that something is not deterministic, before most of science will give up on something not being deterministic.

Are you quite sure about that, with respect to biology? Sure, as an undergrad, most discussion was about the mechanistic aspects of biology, but in grad school (taking, I believe the correct technical term is, a metric-assload of molecular biology courses) I came to realize the stochastic nature of biological processes. This reflects that kind of thinking: http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=16179466

When I was in grad school, the idea of non-linear, chaotic systems started to become popular, and made some of us rethink what random meant, but I not so sure that determinism is taken for granted.

For example, determinism in genetics. You can predict with some certainty that, given a specific gene, the distribution of penetrance of that gene within a population (so, if you want to define that as deterministic, fine), but you can't say with certainty that an individual will express the phenotype associated with gene. Historically, much of the uncertainty has been attributed to the environment. It was only recently that the environment was shown to be more deterministic that previously thought.

Still, most processes important to biology are stochastic or statistical. Do you have references with regards to determinism as a dominant paradigm in biology?

dako, I was referring to complex adaptive systems, not systems that are merely complicated.

Computer hardware* is not adaptive. Most software in common usage, is not, either. But, some software can simulate the characteristics of complex adaptive systems, such as certain adaptive AI algorithms.

I'm not sure why you're lecturing me on this - I didn't say computers were complex systems. I was addressing Ivor's question about computers as complex systems.

I spent several months (years?) trying to model soybean pod development as a complex adaptive system. Kinda hosed me on the Ph.D., 'cause my thesis committee were all molecular biologists. I dunno, I was just following the problem and it turned out to be one where molecular approaches weren't that applicable.

In the end, though, in the papers that came of it, ones that are in review right now, so I can't cite them for you - I dropped the complexity part. It just didn't add anything - the interesting results don't depend on the theory.

The reason I'm addressing your comments is that it seems to me you're trying to do the same thing with evolutionary theory here. There a lot of aspects of biology were evolutionary theory doesn't add anything; those areas are where non-evolutionists gain their credibility.

So when you make overly enthusiastic statements like "all aspects of life", well, you help make them look smarter.


You know, phrases like this:

If aspects of evolutionary theory (even if it is not specifically genes) could explain the development of airplanes, then how are airplanes not subjected to evolution?

I suppose you could try to place Darwinian evolutionary processes into two categories: Natural (no intelligence involved), and artificial (intelligence applied, to some degree). Though, there are huge gray areas between. And, even in artificial selection, the process is never 100%: Artificial selection is nothing more than humans adding their own selection pressures to the otherwise all-natural fitness landscape of life forms.

I'm writing software, right now, to manage crop performance trials in breeding programs, so, I'm curious. How do you defend this statement? What do you mean by all-natural fitness landscape? How do you justify calling artificial selection a Darwinian process?

 

[Wowbagger]

I think we're talking past each other, and that some of the disagreement is semantic.

I was hoping that was the case, actually.

What I mean is that fluid dynamics is useful to test if a building has enough exits in case of a chaotic evacuation. This doesn't mean that the crowd will be a fluid, or even behave like one... It will be humans, stampeeding.

You could then generalize the fluid-dynamics model, call it "chaotic-interaction-of-units dynamics", for those purposes. Both fluids and humans would be units capable of chaotic interaction.

Or, maybe someone can come up with better verbiage?

The OP talked about Darwinism, and so did I. Of course anything that changes over time can be consider to evolve, but this would get to the ridiculous of, for instance, Evolutionary Geology.

"Evolution" is not commonly used to describe geology. However, I'll bet that, in the very generalized sense, it might not be so crazy to do so. Let me check with some of my geologist friends, though.

It's silly and redundant, and there is absolutely no need of dragging Darwin into it.

You are correct, about Darwin: Geology has no units of selection, and no self-replication, etc.

Planes don't evolve. Our notion of what a plane is supposed to look like does.

Semantics.

Not all, I believe, and my example is basically of people who devote themselves to a life of ascetism and isolation. Not a very good one, in retrospect... goes with the rest of my disastrous participation in this thread.

I am sure that, every-so-often, anomalous life forms, that will not reproduce, and are not useful to the rest of society, might occur. However, they tend to... die out. And, the genes that make one prone to be both useless and unwilling to reproduce, become rarer and rarer to find.

My point is that all of those events (maybe not Vietnam, but I already put it in) were completely unpredictable. They were unpredictable because they were driven by ideologies. We can use evolution to explain them post-facto, but we can equally use social and political sciences. Again, no need to drag Darwin into it...

No science could predict these events with complete precision. However, some scientific theories are still better at predicting patterns of war, than others. And, based on what I have read about societal evolution, it seems that evolution is not too shabby in the field.

The biological human is subject to Darwinism, but not the social.

Perhaps you should read a good book about memes. You don't have to agree with the concept. (It is somewhat controversial, and still in a proto-science stage, after all), But, at least familiarize yourself with the concept, before you comment on such things.

If that was your point, you didn't express it very well. There's a big difference between "any aspect of life can be explained" and "adding ... to an explanation".

Not really. It is still true that any aspect of life can be explained with Evolution, as far as I can tell.
But, that does not automatically render all the other explanations useless or bad science (unless they already were). It only means that evolution is another tool one can utilize.

You should pick your words more carefully. What exactly do you mean by "explanation". Perhaps you should cite specific examples from the literature to illustrate your point.

Most of the standard dictionary definitions will be fine, for starters. Although, it occurs to me that testability is an important property to add.
"Testable explanations" might be a better term. But, I'll just use "explanations" for short.

How, exactly, does applying "Evolution by Natural Selection" provide insight into dominance? Again, I don't think you're choosing your words very carefully, so provide an example, please.

Genes combinations that result in dark hair will naturally be more prevalent than light hair, because dark pigment will overpower light pigment. However, things get more complicated if there are survival advantages in having light-colored hair; or if sexual selection favors light hair. Then you would eventually see light hair dominating the population, in ways mendelian genetics can not explain on its own, at least not with any precision.

You do realize that the majority of cases of dominance can be explained in terms of physiology, molecular biology or biochemistry? Read Kacser and Burns (http://www.genetics.org/cgi/content/abstract/97/3-4/639) .

Which, in turn, can be explained in terms of survival advantages (or disadvantages) in the fitness landscape.

Consider the example of cystic fibrosis.

There are a few theories. Resistance to cholera being the most prevalent, it seems.

http://query.nytimes.com/gst/fullpage.html?sec=health&res=9E00EFD6133DF934A35753C1A962958260

It is also possible that its genes confer resistance to typhoid and/or tuberculosis, as well.
http://www.hno.harvard.edu/gazette/1998/07.09/CysticFibrosisG.html
http://www.newscientist.com/article/dn10013-cystic-fibrosis-gene-protect

That's my example. Do you have a counter example to prove your point?

For another example, I read that the genes that cause sickle-cell anemia stuck around, because they also helped a population survive malaria.

http://www.pbs.org/wgbh/evolution/library/01/2/l_012_02.html
http://en.wikipedia.org/wiki/Sickle-cell_disease

No, but you seemed to be.

I am only conveying what I learned from scientists. I am not making anything up willy-nilly.

Remember, I came into this because of your bold statement "I challenge anyone to come up with some aspect of life, that can't be explained by Evolutionary processes". That's over-reaching.

Then prove it. Give me an example of some aspect of life can not possibly be explained by evolutionary processes.

Because there are plenty of people on the anti-evolutionist side who can and do explain life without using evolutionary processes. And they are much more credible scientists than you are.

First of all: I do not claim to be a "credible scientist", I am merely an "armchair" science enthusiast. You do not have to take my word for anything. Hopefully, you will take the time to read the material I cite. (Although, unfortunately, much of it was from books, not web sites.)

Secondly, I would like to ask about the nature of these explanations you are referring to, from the anti-evolutionist side: Are these explanations "intelligent design" or some such equivalent?

If so, I would love to see ID used as an explanation for some aspect of life, that meets basic standards of scientific integrity. I have yet to see such a thing.

If not, what are you referring to? Biochemical processes? Psychological models? As I said before, many of these are legit, in their own way. But, evolutionary explanations could yield more precise results, in other ways.

Or, if we're getting to far off topic, how do we address the original posters question, using the theory of evolution? Specifically, not in some general, hand-waving sense.

The rich and healthy have adapted a survival strategy, where they don't need to reproduce as much, because their children are more likely going to be healthy and survive.

The sick and poor have adapted a strategy where they just try to have as many children as possible, in hopes that some of them will survive.

That summary over-simplifies the matter, some-what. There are a lot of complicated other aspects involved. But, is that a good start?

On the other hand, Rogers and Erlich do not use the term "meme", nor does they cite Dawkins. Are you sure it's correct to apply "meme" here? While the word has certainly spread in the popular literature, it's not seen much in research.

You can write a paper about apples falling from trees, without using the word "gravity". That does not mean you are not describing gravity.

I came to realize the stochastic nature of biological processes.

I see where we might be confused though. Stochastic is a different definition than the one I was using for random, which was closer to that of random chance.

Random chance means predictions will never be better than dice rolls.

Non-deterministic implies that our predictions will never be 100% accurate, but the more we learn, the more accurate our predictions can be: We can out-perform pure dice rolls, to start with. And, we can continue improving predictions, the more we learn.

I accept that much of evolution is stochastic. The form of randomness I am fighting against is the "happy accident" criticism from creationists.

That's no excuse for downplaying the random components of evolution.

There is a general trend: The more we learn about Evolution, the less importance randomness seems to play. If evolution was supposed to be a theory about randomness, you would think the opposite would occur.

Still, most processes important to biology are stochastic or statistical. Do you have references with regards to determinism as a dominant paradigm in biology?

I don't know about "dominant". But, I do know that in the drive to develop empirical results, there is the drive to find deterministic aspects of life, as much as possible.

For example:
http://www.sciencedaily.com/releases/2007/11/071119123929.htm

Random variation could be "random" any way you define the term. But, selection pressures, being non-random, tend to yield converging results in similar fitness landscapes, which can be predicted in very deterministic ways.

I'm not sure why you're lecturing me on this - I didn't say computers were complex systems. I was addressing Ivor's question about computers as complex systems.

Sorry. Out of context, it looked like you were mixed up with what complex meant.

So when you make overly enthusiastic statements like "all aspects of life", well, you help make them look smarter.

Have them come here, with their examples.

What do you mean by all-natural fitness landscape?

That is tricky. Since the spread of humans, there has probably not been any life forms whose evolution has not, somehow, been influenced by human presence. (well, maybe deep in under-ocean vents?)

Though, for quick-and-dirty purposes, you could define "all-natural" as any life forms where humans have not intentionally altered the course of their evolution.

How do you justify calling artificial selection a Darwinian process?

Certain genes made some life forms easier to domesticate, than others. Those that were domesticated found their forms being altered (fruits would be larger, for example, and dogs better able to sniff-out foxes...). Genes that allowed for these preferred alterations would tend to survive and reproduce more effectively, among humans, than those without the favored features.
Even if those features would leave the life form weaker in the wild.

Artificial selection is just another factor that would go into the life form's otherwise-natural fitness landscape.

 

[delphi_ote]

Does this kind of post really clarify anything? I'm really starting to wonder about the way we conduct these discussions...

 

[Earthborn]

Random chance means predictions will never be better than dice rolls.

Even in dice games, predictions can be made which numbers will come up more often than others. With two dice, you'll throw 7 more often than any other number. You can reasonably predict that in a game such as Settlers of Catan, someone's whose "evolutionary niche" depends on the numbers 2 and 12 is going to be less successful than someone who profits from the numbers 6 and 8.

It should also be noted that a single die only produces each number with pretty much the same probability because humans have spend considerable effort in making sure that they do. Nothing in nature behaves that way, because random chance can't produce fair dice. They require intelligent design.

 

[Wowbagger]

Does this kind of post really clarify anything? I'm really starting to wonder about the way we conduct these discussions...

Clarity will improve with practice. At least the rambling gets the thinking going, for some folks.

Even in dice games, predictions can be made which numbers will come up more often than others. With two dice, you'll throw 7 more often than any other number. You can reasonably predict that in a game such as Settlers of Catan, someone's whose "evolutionary niche" depends on the numbers 2 and 12 is going to be less successful than someone who profits from the numbers 6 and 8.

That is correct.

It should also be noted that a single die only produces each number with pretty much the same probability because humans have spend considerable effort in making sure that they do. Nothing in nature behaves that way, because random chance can't produce fair dice. They require intelligent design.

That is one reason why Evolution would be stochastic process, not a "random chance" process.

 

[mijopaalmc]

I see where we might be confused though. Stochastic is a different definition than the one I was using for random, which was closer to that of random chance.

I accept that much of evolution is stochastic. The form of randomness I am fighting against is the "happy accident" criticism from creationists.

Ah, but it is actually you who are mistaken here. If you look at the words probabilistic, random, and stochastic in the technical, mathematic definitions (which it is pretty clear dakotajudo is doing), it is blindingly obvious that all three words are nearly perfectly synonymous. The problem here is that you are letting common creationist usage of "random" or "random chance" obscure the fact that there are many useful scientific application of the mathematically rigorous idea of randomness.

Random chance means predictions will never be better than dice rolls.

So what?

As Earthborn has pointed out, you can still make useful predictions about the outcome of many roles of dice, just as you can make useful prediction about what traits will persist given certain environmental conditions.

Non-deterministic implies that our predictions will never be 100% accurate, but the more we learn, the more accurate our predictions can be: We can out-perform pure dice rolls, to start with. And, we can continue improving predictions, the more we learn.

Actually, in its mathematical sense "non-deterministic" means "probabilistic", "random", or "stochastic". In the sense in which you seem to be using it, it seems to mean "biased" or "directional", which is still covered under the mathematical definition of "probabilistic", "random", or "stochastic".

 

[mijopaalmc]

That is one reason why Evolution would be stochastic process, not a "random chance" process.

But stochastic processes and by definition governed by "random chance".

Why not look at this as the creationists yet again failing to understand technical or scientific terminology such as "theory"?

 

[delphi_ote]

Clarity will improve with practice. At least the rambling gets the thinking going, for some folks.

Half the forum picking apart every sentence of every post again and again? I'm not so sure this clarifies anything. It's just argument for the sake of argument. Everyone seems to be piling on to score points and feel smart. We're just playing to their persecution complex and burying good explanations in squabbling nobody looking for answers is interested in reading.

If our goal really is to explain and change minds, we need to stop being so pedantic. We need to explain things in short, clear prose. We need to stop trying to explain things outside our area of expertise and stop pretending we know everything.

Most of all, we need to stop blasting away with pages and pages of text trying to show everyone we're the smartest person in the thread. Make a good, solid point or two and let someone else have the floor. There are literally hundreds of us to one of them here.

 

[Complexity]

Most of all, we need to stop blasting away with pages and pages of text trying to show everyone we're the smartest person in the thread. Make a good, solid point or two and let someone else have the floor. There are literally hundreds of us to one of them here.

Lead by example, if you can.

 

[delphi_ote]

Lead by example, if you can.

I've been doing my best, but I don't think it hurts to point out the necessity for restraint occasionally.

 

[Wowbagger]

Ah, but it is actually you who are mistaken here. If you look at the words probabilistic, random, and stochastic in the technical, mathematic definitions (which it is pretty clear dakotajudo is doing), it is blindingly obvious that all three words are nearly perfectly synonymous. The problem here is that you are letting common creationist usage of "random" or "random chance" obscure the fact that there are many useful scientific application of the mathematically rigorous idea of randomness.

Did you learn nothing from those endless threads about the difference between non-deterministic systems and randomness?

Stochastic means that the more we know about the initial conditions, and the history of conditions since then, the better our predictions will be. Though, we might never have perfect knowledge, and therefore never obtain 100% perfect results.

Random chance means we can never predict what the next result will be, (any better than "dice roll"), even if we had hypothetical perfect knowledge of all the previous states in the system.

As Earthborn has pointed out, you can still make useful predictions about the outcome of many roles of dice, just as you can make useful prediction about what traits will persist given certain environmental conditions.

Right. That was meant to be included within my "no better than dice roll" comment.

If a system is stochastic, on the other hand, we can do even better than that. Our predictions from the Theory of Evolution might not be perfect, but are often better than anything we can derive from merely rolling dice.

Why not look at this as the creationists yet again failing to understand technical or scientific terminology such as "theory"?

That is another perfectly valid tactic we can use. I am only one person. I can't run off all the arguments all by myself!

If our goal really is to explain and change minds, we need to stop being so pedantic. We need to explain things in short, clear prose. We need to stop trying to explain things outside our area of expertise and stop pretending we know everything.

I accept this as valid criticism of my postings, and will take it into consideration. (Although, I never claimed I know everything.)

 

[Walter Wayne]

I would respond by saying there is a difference between the models, and the nature of reality. Our models could be deterministic or not. But, unless demonstrated otherwise, there is little (if any) reason to go off assuming something is not ultimately deterministic in nature, even if we can never quite get at it.

I'm am not assuming it not determistic for little reason. I am reasoning that it isn't based on knowledge of the process of mutation (randomness) and the qualities of systems that cause randomness to be "exagerated" at the macroscopic level.

Heredity and a dynamic selection landscape are among factors that will prevent randomness from being "washed-out" at the macro-scopic level.

You have to demonstrate, to the same degree Heisenberg did, that something is not deterministic, before most of science will give up on something not being deterministic.

Given the knowledge we currently have of the base level genetics, what we know of certain systems and how they change to small variations in input, it is in fact more reasonable to believe that evolution is random than non-random. Quantum indeterminism was being developed at a time when pretty much every phenomenon explored was thought to be completely determistic in nature. The level of demonstration required in order to show randomness, is completely different now that we have more knowledge.

Stochastic means that the more we know about the initial conditions, and the history of conditions since then, the better our predictions will be. Though, we might never have perfect knowledge, and therefore never obtain 100% perfect results.

That is most definitely NOT what stochastic means. Stochastic pertains to randomness, about not knowing the next state based on the current state. It is true that determistic systems are sometimes treated stochasticly. When information is sketchy or processes very complicated, a stochastic model can be more accurate than trying a vague model. So the fact that something is modelled stochasticly doesn't mean it is random or not random, but stochastic still pertains to randomness and does not mean what you said it means here.

Walt

 

[mijopaalmc]

Did you learn nothing from those endless threads about the difference between non-deterministic systems and randomness?

Stochastic means that the more we know about the initial conditions, and the history of conditions since then, the better our predictions will be. Though, we might never have perfect knowledge, and therefore never obtain 100% perfect results.

Random chance means we can never predict what the next result will be, (any better than "dice roll"), even if we had hypothetical perfect knowledge of all the previous states in the system.

Right. That was meant to be included within my "no better than dice roll" comment.

If a system is stochastic, on the other hand, we can do even better than that. Our predictions from the Theory of Evolution might not be perfect, but are often better than anything we can derive from merely rolling dice.

Wowbagger, it is painfully evident from the above post that you inf act do not understand what stochastic means in its technical, mathematical sense.

Here is a brief description of what mathematicians and mathematical biologist mean when they call something a "stochastic process":

Basically, the axiomatization of probability theory begins with the creation of a mathematical space called a probability space designated by the ordered triple [latex]$(\Omega, \mathcal{F}, \mathbb{P})$[/latex]. [latex]$\Omega$[/latex] is a set, which, for our purposes, is almost any collection of objects. If [latex]$\Omega[/latex] is finite or countably infinite, the probability space is called discrete. If [latex]$\Omega[/latex] is uncountably infinite, the probability space is called continuous. [latex]$\mathcal{F}$[/latex] is a family of subsets of [latex]$\Omega$[/latex] called a [latex]$\sigma$[/latex]-algebra whose members share certain attributes and are known as "events". In particular, a [latex]$\sigma$[/latex]-algebra is closed under complementation (i.e., the "opposite" of every event is also an event) and countably infinite unions (i.e., a collection of events is also an event). [latex]$\mathbb{P}$[/latex] is a function called a probability measure that maps each event in [latex]$\mathcal{F}$[/latex] to the interval [0,1] in such a way that [latex]$\mathbb{P}(\Omega)=1$[/latex] and the probability of the union of mutually exclusive events is the sum of their respective probabilities.

A random variable is, by definition, a function, [latex]$X$[/latex] from the probability space [latex]$(\Omega, \mathcal{F}, \mathbb{P})$[/latex] to another measurable space, most often [latex]$(\mathbb{R}, \mathcal{B}(\mathbb{R})$[/latex] , the real numbers and the Borel [latex]$\sigma$[/latex]-algebra on [latex]$\mathbb{R}$[/latex] (i.e., the smallest [latex]$\sigma$[/latex]-algebra form by the open intervals of [latex]$\mathbb{R}$[/latex]). The random variable defines a probability measure, known as a pushforward probability measure, on the measurable space [latex]$(\mathbb{R}, \mathcal{B}(\mathbb{R})$[/latex] such that [latex]$(X_*(\mathbb{P}))(B)=\mathbb{P}(X^{-1}(B))[/latex]. In other words, that is the pushforward probability measure of [latex]$B\in\mathcal{B}(\mathbb{R})$[/latex] equals the probability measure of [latex]X^{-1}(B)\in\mathcal{F}[/latex], the preimage of [latex]$B$[/latex] in [latex]$\mathcal{F}[/latex] (i.e., [latex]$\{A\subset\Omega}\}\in\mathcal{F}$[/latex] that maps to [latex]$\{B\subset\mathbb{R}\}\in\mathcal{B}(\mathbb{R})$[/latex]). This pushforward measure is called a probability distirbution.

A stochastic process is a family of random variables [latex]$\{X_{t}\}_{T\in{t}}$[/latex] for an index set [latex]$T$[/latex] If [latex]$\Omega[/latex] is finite or countably infinite, the stochastic process is called discrete. If [latex]$\Omega[/latex] is uncountably infinite, the stochastic process is called continuous.

Now, since the only thing that the random variables, probability distribution, and stochastic process have in common is that they all originate in a probability space defined by a probability measure.​

In other word the classical examples of randomness (i.e., flipping a fair coin, rolling a fair die, drawing a card from a shuffled deck, radioactive decay, etc.) are just as much stochastic processes as biological evolution or gas dynamics.

 

[Wowbagger]

Wowbagger, it is painfully evident from the above post that you inf act do not understand what stochastic means in its technical, mathematical sense.

Perhaps a general example of where this difference is applicable would help.

Mendelian genetics might predict that the probability of gene "X" showing up in the population is 25%. If reality was that simple, you might as well roll a 4-sided die, to try to predict who will have it or not.

But, reality is not that simple. Evolution could explain in better detail, the phenotypes of that gene, and its effects on survival in the given environment. The more we learn about these effects, and the gene's lineage, the better we can predict who will have it, or not: It is beats the die-roll.

So, it turns out genetics could well be described as a stochastic process.

It is not the completely-random-chance nonsense, analogous to a lucky "dice throw", that creationists like to claim it is.

 

[delphi_ote]

In other word the classical examples of randomness (i.e., flipping a fair coin, rolling a fair die, drawing a card from a shuffled deck, radioactive decay, etc.) are just as much stochastic processes as biological evolution or gas dynamics.

It all comes down to the model and parameters, though. Some outcomes in the state space can be much more likely than others.

I study probabilistic systems for modeling evolution professionally right now. If you're interested in clearing up any specific questions about this, I'd be more than happy to try to answer.