What exactly is natural selection and precisely where does it occur?

I've actually said quite the opposite. Whilst the genecentric natural selection is superior - it is much more difficult to grasp than simply survival of the fittest (survival selection) coupled with reproductive ability (fecundity) etc. Of course, just looking at the simple bits of a model is not discussing the exact and precise details of it, are they? Yes, Hoot Mon introduce genecentric natural selection and some people were almost outraged by the idea and railed against it. I came in to support this view point as being superior and slowly people have begun to accept its import. If only they will concede that Hoot Mon has been on this since page 1.

You said earlier: I say that the gene's eye view ignores this because it isn't natural seleciton. Your bad luck scenarios are akin to random selection (ie selection happening to an organism regardless of its genetic heritage) and I don't believe that random selection is part of natural selection. I think it is quite possibly more akin to genetic drift.You basically said that 'selection can operate on non-inheritable characteristics'. I agreed, but stated that this selection is not natural selection.

It might be difficult to demonstrate given the medium. However, I can highlight why one model is inferior to another by showing its weaknesses and how another model does not share those weaknesses.I have only touched on the issues of course, once again the medium prevents full intercourse. Gould and Dawkins wrote lengthily about their views and reference to them has been made for better treatment of the subject.I've been perusing my copy of Gould's 'Structure...' and his argument against the gene view seems to be confused and based on a misunderstanding of the genecentric view. He asked questions of the genecentric view similar to the ones you ask. A fit individual is one which works towards ensuring its alleles replicate. No - it is not dependent soley on genetics, as I have been saying for some time. Acquired characteristics can affect fitness. This is why natural selection doesn't select the individual - it only selects that individual's heritable traits (of which there usually many copies of). No, they change due to the ability of the allele to, on average, work with other genes (and their alleles) well to create individuals that aid in the replication of that allele. Alleles that provide better aid on average will tend to increase in frequency, those that aren't so good will tend to decrease in frequency. One simply has to calculate how well that allele functions towards causing its own replication. I'd imagine replications per [time period] or per generation would be a good way of realistically measuring it.

I don't think a scientific term should be left to individual preference. We need to have a precise understanding of it - even if we gloss over that as an explanatory tool to begin with. Agreed. However, the meanings of the terms is greater than the sum of their parts. Moreso with natural selection. Pick a card any card - that is selection occurring that is natural. It is not supernatural! However despite it being selection that is natural, it is not natural selection. As you say - that term has its own specific meaning. Yes - that man is an animal that is part of the ecosystem, means that its actions can be involved in natural selection (that is man, can cause the increase of or decrease of the frequency of genes of other species (that's nothing special in itself, lions do likewise). Artificial selection refers to specific kind of natural selection. Natural selection artificed by natural agents with foresight. Indeed - most people think that artificial selection is entirely contrastual with natural selection. I do not, and this is the topic to discuss that, neh? I didn't invent the concept - and I'm not really substituting. I am simply describing relationships. It is perfectly fine to use aritificial selection to differentiate from natural selection. Since we are being precise here, I put forward the idea that artificial seleciton is a subset of natural selection where the selection pressure is in getting another species (with foresight) to aid in replication. Chickens are the most successful birds on earth because they fill this niche so well.

No - your diagram was insufficiently explanatory for me. Natural selection doesn't follow anything, it seems to be labelled as the entire list except death. Consider this: a group of individuals with no genome. They have been built by man. They can make new individuals at random (randomly created individuals are commonly rubbish at making new individuals). Some are quicker at it than others. There is no natural selection here. Each individual that gets created will probably be rubbish, and so will make rubbish new individuals. If a randomly good individual is created, its offspring are probably going to be rubbish anyway.Here we have differential reproductive success without natural selection.However, if these individual carried precise instructions with them on how they were built - then we'd see natural selection. Good instructions (that create good and quick individuals) will increase in frequency in the population.Here we have differential reproductive success that leads to natural selection. If all of these individuals were created with the same instructions there would be no change in the frequency of that set of instructions. There would be no differential reproductive success and there would be no natural selection. So individuals who don't get to reproduce are selected out, and become less frequent in the population right?Social insects are doomed! A struggle for survival is just survival selection. It differs from, for example, sexual selection. I take no issue with any other form of selection. Many forms of selection are a subset of natural selection. Sexual selection and survival selection are two examples. That is true. Not all types of selection are natural selection. Picking out an outfit is not natural selection. I have no problem with picking out an outfit (as long as you just get on with it!) It does. It misses kin selection for example. No the individual selection inadvertantly includes types of selection that aren't natural selection (at least Quetzal's description of the individualist view). That's fine - but I feel Hoot Mon understands the basics already - he has done a fine job of discussing the intricacies and the limitations of the individual point of view. Certainly not a perfect job. It is like trying to explain the Bohr model of an atom with somebody who is asking which model is the most accurate and making a good case for why the Bohr model is not the most accurate.Maybe you are right - and Hoot Mon has dived in at the deep end, but he has done a good job at the deep end and he seems to be doing fine. Trying to convince him to doggy paddle at the shallow end will probably be met with scorn.

Clever come back. I 'get' that you don't think I have done this. I am still waiting for a decent individualist account of social insect selection. They are the kinds of questions those that don't understand genecentrism ask. Indeed - and the questions were answered. I have. The point I've made is that 'fit' individuals don't necessarily get naturally selected. That is why the gene view is better. Naturally a phenotypical trait has fitness implications. It squares with genecentrism when that phenotypical trait is caused by the genes. When it is not caused by genes it is irrelevant to natural selection. You are asking about individual fitness. Obviously since I do not believe that individuals get selected - the two concepts won't gel together (which is essentially my point). Essentially to both - since neither captured the essence. I then provided a more accurate accounting of how allele frequencies change in the genecentric view. Yes - the gene can be viewed as an agent (or rather, the sum total of all the genes and their alleles), but I thought I'd give you a more complete understanding of my position since it is a little more involved than all that - it involves tendencies and the like. They work together by creating good (or in many cases, bad) replication machines. In the environment where the sickle cell genes work together well (and in concert with other genes and across the whole population), they do so because other alleles cannot create machines that hold off malaria as well. I wouldn't dream of doing so. An organism may be fit for extra-genetic reasons (such as cybernetic eyes), or an organsim may be fit for genetic reasons (pretty feathers). Since an organism's 'fitness' is not inherently tied into the genes they cannot be the ultimate entity subject to natural selection.Edited by Modulous, : No reason given.

You just said that natural selection is a term with its own specific meaning. Are you recanting?I'm not sure what is confusing about my definition, its the same as everyone else: Alleles which do well at promoting their own replication are selected to increase in frequency compared with alleles that don't do so well.The only difference is that I don't agree that replacing the word Allele with 'individual' makes a great deal of sense and can lead to some paradoxes. The phrase has a meaning. Selection by artifice, but a certain kind of selection counts. It's perfectly simple. Farming and agriculture involves artificial selection. I don't see why that's difficult. That I consider artificial selection a well defined part of the exact same mechanism that is natural selection is hardly massively controversial. And I have tried to explain what natural selection exactly is, and that artificial selection is actually (and surprisingly) a subset of natural selection. It certainly hasn't been my central point, and I think I only mentioned it as a side thought that you have gotten confused about. Others in this thread (Quetzal) have expressed understanding of the concept. No it isn't. It is a synonym for all the available detail there is. I agree with wikipedia. I don't think it inherently disagrees with me. And I agree with those definitions. Natural selection has a precise meaning and we need to find it here. Artificial selection has a precise meaning and we can discuss it here if people wish.I have been quite clear how Artificial Selection can be said to be a subset of Natural selection. If you want a more complete treatment of the subject I'm happy to spend more time on it, it's not vital though.

I think you are confused about what was being said.Let me try again.To get natural selection you need to have a population with differential reproductive success. If there is no differential reproductive success there is no natural selection. You surely agree with that?Thus what I was saying was:Differential reproductive success + instructions leads to natural selection.A population that has been 'paused' can still have differential reproductive capability. If we know that there will be differential reproductive success and there are instructions in play we can predict that natural selection will follow.That's all I was saying.Naturally if we know that natural selection will take place then we can likewise deduce there are instructions and differential reproductive success. However, that is a backwards way of trying to understand natural selection. Indeed - you see him struggling to keep his head above the water. I see him needing to refine his strokes while he his laughing at the kiddies in the shallow end.

Its certainly worth pointing out the problems with it. Gould goes to great length to try and point out the problems with genecentrism, and Dawkins does the opposite. I've never said that. Where artificial means unnatural. That's what I have been saying a lot of. I've also said that not all 'selection that is natural' is natural selection. It's not obfuscative at all, its quite straightforward discussion on how things are related to one another. Only that it should be viewed that way when seeking a full understanding of natural selection. There are plenty of times when it isn't necessary or wise to view it this way. Which has been my point. Natural selection is more than selection that is natural. It means something.We're here to discuss that very thing. I think I know what I agree with. And indeed - I agree. That doesn't mean they are mutually exclusive! Did you check what precise means? You might find for example: Clearly, fully, and sometimes emphatically expressed. Yes, I'm clear on what you think. I don't think that, that's why I'm happy doing it. If I thought he couldn't handle it I wouldn't. However- I've hardly replied to Hoot Mon in this thread. My first reply was to crashfrog and I mostly ignored Hoot Mon's responses. I spoke with AZPaul and Quetzal. It wasn't until much later that I really responded in any detail to Hoot Mon. You should probably bare that in mind - I was just trying to explain what Hoot Mon was trying to explain to other people to those people. I wasn't trying to explain genecentrism to Hoot Mon - he already seemed to have a grasp of that. Assuming Hoot Mon is dead wrong, your right. I don't think he is. He raises many of the arguments that have flown about between people like Gould and Dawkins. He has gotten things wrong and I've attempted to teach him some of those things, but I've not corrected him where he has been right. When I originally mentioned it I provided the context. Surely you can look back and see that context? I can't explain it any further. I've provided my rationale for considering art. selection as a subset for nat. selection. Either you want me to expand on that or explain certain things, or you don't. That means art. selection is its own thing.I have it in a book somewhere, and I'll make a new thread of it if you like.

I gave you an example scenario where there was differential reproductive success and no natural selection. If you have differential reproductive sucesss you might also have natural selection, but you need some kind of hereditary instruction set as well. Not at all! Quite the contrary - lineage selection is a position that he got from Gould - a a selection type I have argued against as being natural selection. Group selection is not natural selection. He isn't concluding its a high level overview from me. I have been arguing a reductionist point of view which shuns the 'hierarchy theory' that Gould was a fan of. Which nearly correct. If you have natural selection, you have evolution - by definition! However, he also says that evolution does not equal natural selection - so though he might use the term, he truly isn't actually saying the one is equal to the other. And that is exactly what I agree is artificial selection. It really hasn't. It just allows me to include the process of artificial selection within the paradigm of natural selection. What is the most successful bird on the planet? The chicken! Why? Because man's genes benefit by propagating chicken genes. Not all chicken genes are happy about this, since they are made extinct, but some chicken genes have flourished in this niche.

The questions are not bogus. If you understood the genecentric view you'd not be asking those questions (since the answer would be apparant). Maybe they were just for rhetorical purpose, to demonstrate disagreement. I don't think I am denigrating it. I am simply saying that one comes across certain paradoxes when looking at the individual approach. Oftentimes it is a perfectly functional approach and have said so quite a lot. I didn't bypass the fitness questions. I answered them, I said you'd measure a genes fitness in replications per time period. An individuals fitness is difficult to calculate because it depends on what we are saying it is fit for. Reproducing? Surviving? Growing? All of these things? Well of course it makes the distinction. Selection is the process of alleles replicating more than others. Evolution is the resulting change in allele frequencies. Evolution can happen without selection. Mutation events for example. Selection is just one way for allele frequencies to change, one of many that occur in biology. Message 156,

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One simply has to calculate how well that allele functions towards causing its own replication. I'd imagine replications per [time period] or per generation would be a good way of realistically measuring it.

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No, genetic determism is the belief that an individual's behaviour and body is soley (or mostly) determined by the genes. I don't think that is the case. You asked what a fit individual was, in context of genes and I answered thusly. If you want to know some other fitness measurement, then we can discuss this too sometime. A fit individual could be one that lives the longest, if you'd like - but that is not a fit individual in gene terms. An individual who is fit because of some acquired characteristic - such as bionic eyes - may well replicate his genes more than somebody who does not have this acquired characteristic. This is not natural selection though. The genes don't determine perfectly the phenotype, they are not totally linked. So an individual might be fitter than his genes would make him. His reproductive success is not genetically related and so it isn't natural selection. Behaviour can be an extension of a phenotypical trait (ie a brain structure that leads to a certain behaviour). And yes, it has a fitness implication. Genes that cause behaviours in their vehicles that helps those vehicles replicate those genes will be positively selected for. You said: The relationship between selection and fitness is plain in genecentism. A gene that replicates itself (or helps replicate copies of itself) is fit - the more it can replicate and the faster (compared to its alleles) the fitter. Fit genes tend to be selected to replicate more. They don't always replicate more, but the tendency is for fit genes to do so.The fitness of an organism is not something that means anything. Fitness to do what? Fitness to aid its genes in replicating? Its the only thing that I can draw out of it. The reason it doesn't mesh is because sometimes that fitness is not caused by a hereditary trait. Since natural selection is only selecting hereditary traits, a fit individual aiding its genes isn't going to pass that useful trait on, so there is no natural selection going on.Assuming the trait is randomly acquired, its positive effect on the lucky individual's genes is cancelled about the positive effect on the competitor's genes too (and thus competetive alleles). The tendency for this kind of selection is towards not altering the gene frequencies. Any deviation from altering the gene frequencies is just a random drift of sorts.This is not natural selection yet the individual is being positively selected for. Hopefully now you understand that the fitness of an allele can be explained without reference to individuals yet individual's fitness is difficult to discuss without reference to genes. A gene's fitness is measured in replications per x and compared with its alleles' replications per x. Edited by Modulous, : No reason given.

Well - it's time to sum up. What is natural selection, and where does it occur? It's a fine question and trying to answer it means we have to answer other questions along the way - a fruitful discourse!The big question is of individual and gene view selection. Some 'Neville Chamberlains' have proposed a compromise, that both views are valid depending on the situation.Here is my view of that. Most of the time, what is in the interest of an individual is in the interest of a gene, and visa versa. This is not always the case though, so when we look at selection we need to be careful. What if a gene could find a way of replicating faster - to the detriment of the individual? The frequencies of this allele will rise, but the individuals possessing it will be less reproductively fit than those that don't. They have less babies, but the allele spreads and spreads and spreads. Pretty soon most of the population has this allele. The individuals are becoming less fit by the generation! How are they being positively selected for!?The answer lies in genecentric vision. Segregation distorters exploit meiotic drive. The Mouse t-haploytpe is an example of one. Normally 50% of your genes are passed on at reproduction. However, some genes cheat! They manage to ensure that they will be passed on as much as 95% of the time. They are usually detrimental to the individual who has them, and fatal to those that have two of them. However because the victims don't need to make as many babies to ensure the gene is passed on...it doesn't matter.Natural selection shaped these genes, and natural selection ensured that they flourished (until the deme goes extinct, which is not unheard of).One misunderstanding that I think might have happened is that the genecentric view ignores the individual entirely. This is not so. One way for allele frequencies to shift is for those alleles to be selected. However, there is more than one way for a gene to be selected. One way is for it to be good at cooperating with other genes in making vehicles which are good at replicating it. Another way is to 'cheat' as in Intragenomic conflict.Cheating is a short term strategy - since in the long run the survival penalty will outweigh the replication bonus.Genes act to either directly replicate themselves more than their alleles (cheating) or do so by building good vehicles that ensure replication or by building good vehicles that build good vehicles (houses, dams, shells, webs) that aid in replication. We could say spider webs get selected based on how well they catch flies and allow the spider to do its other tasks, but that would miss the real selection at the spider level which is getting selected for building good webs (after all, some webs are good by accident), but we would miss the natural selection at the gene level which is selecting genes that work well together to create spiders that create webs.Finally and once again: the individual level is usually good enough because what is good for the individual is often good for the gene. There are some exceptions to this. There are some things which are bad for the individual but good for the gene. Since evolution is about allele frequencies, this is what is really being selected. WE could talk about change in phenotypes over time, but that would only be the broad strokes of evolution not the real thing (missing leg frequency probably increases in time of war, but that isn't evolution).I think the answer to where exactly does natural selection occur is at the gene level. Not the individual, the deme, the species or any other place in the heirarchy. There may be selection occurring, but it is not natural selection.