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RQ#03 Is there really a non-natural selection?

I haven't done a random question in a while. This is the third one, apparently.

A grocery store still life, primarily Brassica oleracae
Lately I've been involved in some fairly theoretically discussions about evolution, which tend to push one to pay more attention to terminological precision. Or get very confused And get very confused regardless. Additionally, I hang around some biologists with minority opinions on certain aspects of evolution, and ultimately end up talking about evolution differently, to the point of using different words or same words differently. The usual side effects of specialisation. This becomes particularly evident in heated argument with someone outside your tribe – you start speaking slightly different dialects, if you will. Of course, where there's variation, there's opportunity to pick the variant that suits you better. Ideally, that has something to do with accuracy, since we are, hopefully, still attempting to do science and what-not.

Let's start with the easier of the usage and terminology discrepancies – the term 'natural selection'. Is it useful or does the simpler 'selection' make it redundant? I tend to drop the 'natural' part; laziness and word limits may help, but I think there may be valid theoretical or philosophical merit in doing so:

1. 'Natural selection' was initially proposed in contrast to 'artificial selection', which was used as an effective pedagogical/explanatory move. It got the point across, particularly in an age when humans were unquestionably special and distinct from the natural world. Nowadays, few scientists would seriously make a distinction between human and non-human nature in the context of biology, and thus there really is no artificial selection per se. 'Artificial selection' is 'natural selection' performed by humans to pressure their organisms towards traits the humans find favourable. In this case, the humans are part of the environment, playing a similar role to predators, except they breed the variants they like instead of instantly culling them. With no need for an 'artificial selection', is there still a need for 'natural selection', since there no longer is a valid contrast?

2. 'Natural selection' is often equated with adaptation. This isn't to say 'selection' by itself isn't, but 'natural selection' is the variant used most often in popular writing, some of which can be careless and inconsistent with its terminology. While presumably many of the authors do truly understand that selection and adaptation are different things, adaptationism has led some to consider the difference irrelevant. If adaptation is the sole phenomenon responsible for all the observable or cool things in biology, does it really matter if it's used interchangeably with natural selection? When a term is learned and frequently used incorrectly, it is extremely difficult to fix even in an individual, let alone a population. While 'natural selection' is not meant to be conflated with adaptation, it is, and has thus been tainted.

3. Use of 'natural selection' implies that phenomena like sexual selection and kin selection are somehow distinct, or special. These are secondary phenomena, special cases or manifestations of selection. That is, sex and kin selection are subtypes of 'natural selection' and do not lie on equal hierarchical level as it may first seem. While most of the scientific community has no problems understanding this, it is perhaps not the clearest delineation of the terms for the general public or students. This way, we can also keep 'artificial selection' to refer to domestication (although I don't see the necessity in doing so) without it contrasting with the 'natural' kind.

4. This is the least important point, but rather a more personal one. I dislike Darwin-worship; I'm not a 'Darwinian' (nor a "Neo-Darwinian), don't know what that means and frankly don't consider this question relevant now, over a century after Darwin's death. While history of science is indeed fascinating and undeniably worthwhile to learn about, we shouldn't trap ourselves in our history. In fact, I think equating evolution with Darwinism is a bit offensive to all the hard work and frustration of subsequent researchers that have contributed to the field – do they not matter? They work for evolution, not Darwin. 'Natural selection' has been too often tightly associated with 'Darwinism', and often plays a part in Darwin-worship. In other words, the term has acquired some baggage; mind you, not through Darwin but rather through his fervent supporters afterwards.

5. Population geneticists seem perfectly happy with just 'selection'. They're the ones who actually study the mechanisms of this stuff, so if it works for them, perhaps it should be adequate for the rest of us?


I don't mean to nitpick on words and 'mere semantics', but given the difficulty of conveying ideas to those outside your field and the general public, any site of potential confusion is worth trimming if we can. Those on the writing end are also prone to sloppiness and mistakes, so we too are susceptible to the confusion potential. That said, 'natural selection' has stuck around for this long – perhaps there is a beneficial reason I missed out on? This is an honest question – I've never really been formally trained in evolutionary biology save for a basic first year level, and may thus miss large chunks of theory. As I mentioned before, I'm being 'brought up' in some minority circles of evolutionary thought.

Why should we still use 'natural selection'?
Your turn. Just be gentle with the philosophy – I'm rather slow at following complicated abstract theoretical discussions, which is why I do experimental science ;-)

15 comments:

  1. Oh Hi.

    I think the artificial to separate what humans did to separate it from natural is ok. That's what the word artificial us used to, to specify when something was done by our species.

    I think the term 'natural selection' is the symbol of 'selection' but it means it's a biological thing. It would be 'biological selection'. Think of it as a trademark. You say natural selection and you already know you are talking about biological entities evolution mechanisms.
    Also we know selection doesn't only affect biological entities. We are made of the matter we are made of because our subatomic atomic and molecular components are the ones that are stable in our planet temperature and gravity conditions. Is that natural selection? Well yes... it's natural... and it's a selection... but maybe it's not exactly the same cause no one is being replicated based on a genetic code here. So I think the term has a right to exist.

    Also, as a meme, if it had survived it's because it has been selected :P
    You can argue about it rationally, but if you want to really fight it, find out what are the things that sustain it alive. :)

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  2. - Not all biological selection is genetic. If you have a non-genetic inheritance system, presumably similar principles would apply pertaining to the suppression of the sufficiently inadequate. Thus, is there anything really special enough about natural/biological selection to warrant it receiving its own distinct name? Are the principles of, say, economic or cultural selection really all that different?

    - If an idea, or organism, has survived, it means it has not yet been weeded out by selection. Does not necessarily imply it's been selected 'for'. But that's the topic of a later random question...

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  3. I didn't say what they are selected for, but what it sustain it alive. Like, if you have a population of sugar addicted people, that keeps your candy store business running. If you change that environmental conditions you are broke.

    Well, if life forms are not so special to have their own specific kind of selection, when why don't we just say that you are also an anthropologist or an economist? Maybe the selection in one field doesn't work exactly as the selection in other fields.

    I see another problem with the idea of selection if we get picky.
    The environment is not selecting anything. There is no selection, what happens is a failure to survive enough to propagate your characteristics, I won't call that a selection! I'd call that a 'generational inheritance failing rate' or something like that. It's the individual who is failing. Not that the environment is chosing. Except in artificial selection when the environment is actually chosing! hahaa :P

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  4. - That meme selection comment was regarding the usage of the term 'natural selection'; I don't think there are selective pressures strong enough to streamline our terminology to perfection given current environment; in fact, these pressures become more relaxed in specialist circles where we all know what we're talking about and slightly misusing words doesn't really cause any problems. But I think we somewhat agree there anyway; it's a digression...

    - I'm not against specifying subtypes of selection – again, I'm perfectly fine with sex selection when speaking of sexual dimorphism-related stuff, and kin selection in explanations of familial cooperation. I'm just not sure that we need to specify biological selection to be 'natural' when speaking of it in general. The selection in kin and sex selection is actually the same, it just manifests differently. Differential survival, etc, still remains.

    Not to get into definitions and fine semantics (I suck at those), but IMO selection is basically the 'differential survival of types of individuals in a population', usually due to their interaction with the environment but I'm not sure that's even necessary for the definition. To use more general terminology, we can say 'differential persistence of types of elements in a set', I think. This applies equally to biology, economics, culture, language, etc. Also, as far as I know, while heredity is a precondition for evolution, it is *not* a precondition for selection.

    I'm not also an anthropologist or an economist because I don't look at those systems. I'm not sure this analogy applies to our discussion though.

    - You're right, the environment isn't 'choosing' or 'driving' towards anything, strictly speaking – that is indeed a common misconception in adaptationist circles. I don't think this is the right place to debate the existence of selection though – maybe a later question! Otherwise we start to cover too much ground... long story short, I personally believe selection exists; and the assumption that selection does exist is kind of key to this discussion...

    Also, I'm not a Cartesian dualist, so choice is irrelevant and non-existent to me philosophically-speaking. And I think we're speaking philosophically at this point ;-)

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  5. About genetic inheritance, it wasn't my point if it was only genetic code based or not! Don't miss my poooint.

    I was thinking, if natural selection is going to be applied on living beings, we'll have to define what a living being is.
    And if that kind of selection has any particular property of itself that makes it different...

    And as I said 'natural selection' only works as a tag for something specific. It refers to the the mechanisms of a specific process observed inside a specific field of study.
    Discussing on the word 'natural' makes me remember of a moron in maths class at my college trying to debate on the 'real numbers' and 'natural numbers' meaning. why the real numbers were 'real'? Were the 'natural' ones more 'natural' for a reason? they were less 'real' than the 'real' ones? Like if they weren't only mere tags, symbols for something...

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  6. What about keeping the 'natural selection' for speaking about systems that evolve based on inheritance?
    (artificial selection would be just a sub-type of natural selection)

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  7. I just think the tag might be misleading and superflous, especially for reasons #2 and 3 in post above. Yes there are natural numbers, but we only use the term when there is a necessity to contrast them with real numbers and integers, etc. What I wonder is – why we can't just use the simple 'numbers' analogue when speaking of selection; and does 'natural' selection actually mean anything specifically? If kin and sex selection were not forms of 'natural selection', then the term could still be useful as an 'other' category – I'm a protistologist, I don't mind paraphyletic terms ;-)

    Since I don't believe in agency of any sort, 'artificial selection' is in no way distinct from natural selection other than that it involves humans (vs other species) imposing additional pressures/constraints. See point #1. So I can't understand what 'natural selection' really is that 'selection' isn't. That would make the tag superflous, not useful.

    - Selection has nothing to do with inheritance. Evolution does, adaptation does, but not selection. If some element type is consistently deleted from a set, it's being selected against, even if it has no bearing on the contents of future sets. It won't evolve because there's no inheritance, nor will any adaptations form or what have you, but selection will still be there. At least that's how I understand it anyway, might be wrong...

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  8. Answer to your last paragraph:
    That's what I mean when I say 'natural selection' could be used when you are talking about selection inside a system with inheritance.

    I think that's a good use for the tag. Just add 'natural' to it and it will be known that you are talking about selection inside an evolutionary context.

    I am sorry I am a spanish speaker I am used and love to have redundant information in every term I use when I speak :p


    But I think the tag is not used that way. Actually the word 'natural' besides the 'selection' is there to mean that NO SENTIENT VOLITIONAL BEING is making the selection.
    Nor a human.
    Nor a god or fate.

    So, Artificial Selection, or just 'Selection' >:) is when humans are doing it.
    And Divine Selection would be when a god is doing it :)

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  9. I mean, the reason why the meme Natural Selection is surviving is because it keep the concept separated from the hand of a god.

    Of course in our scientific context when we already forgot that someone could even think about a god when wondering about the universe and life, the word natural has no function in there.

    But it does in a wider context.

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  10. I think the term natural selection is a metaphor to describe a process of selection or environmental filtering at least when we refer to that process in organic/biological evolution.
    Of course the environment is not acting purposefully or teleologically to select individuals/units, but it works as an external acting evolutionary force in determining which forms are gonna predominate in a population across generations under some specific ecological(biotic+abiotic) conditions.

    Selection is a ubiquitous process that can be seen in a great variety of systems (i.e. biological, chemical, cultural etc). Philosophically it has been equated with a tautology though. It is usually biologically defined as "differential reproduction of genotypes/phenotypes within a population". I would think that selection would always occurs in a population of things that can reproduce, and reproduction means some kind of inheritance, no matter if it is complete or incomplete.

    I agree in that the sole term of selection could be maintained, I don't actually care much about semantics. Natural, artificial, kin and sexual selection are the same thing, they are all types of selection. But there could still be slight differences. For example, Sexual selection focuses more on trying to "improve" two of the three aspects of fitness, mating and fertility, instead of survival. They all select for the fittest under some specific circumstances anyway.

    Selection and adaptation should be decoupled as Gould repeatedly argued, but that also depends on the definition of adaptation you adopt. Futuyma distinguishes two different definitions of adaptation, the historical one that says that any adaptation is the result of natural selection that has selected the trait because it conferred an advantage to the organism in the past. The other definition of adaptation says that an adaptation is any trait whose absence would be deleterious to the organism, and this means that natural selection is not the only way in which they can arise.

    Sorry for the unconnected ideas :P

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  11. I think the term natural selection is a metaphor to describe a process of selection or environmental filtering at least when we refer to that process in organic/biological evolution.
    Of course the environment is not acting purposefully or teleologically to select individuals/units, but it works as an external acting evolutionary force in determining which forms are gonna predominate in a population across generations under some specific ecological(biotic+abiotic) conditions.

    Selection is a ubiquitous process that can be seen in a great variety of systems (i.e. biological, chemical, cultural etc). Philosophically it has been equated with a tautology though. It is usually biologically defined as "differential reproduction of genotypes/phenotypes within a population". I would think that selection would always occurs in a population of things that can reproduce, and reproduction means some kind of inheritance, no matter if it is complete or incomplete.

    I agree in that the sole term of selection could be maintained, I don't actually care much about semantics. Natural, artificial, kin and sexual selection are the same thing, they are all types of selection. But there could still be slight differences. For example, Sexual selection focuses more on trying to "improve" two of the three aspects of fitness, mating and fertility, instead of survival. They all select for the fittest under some specific circumstances anyway.

    Selection and adaptation should be decoupled as Gould repeatedly argued, but that also depends on the definition of adaptation you adopt. Futuyma distinguishes two different definitions of adaptation, the historical one that says that any adaptation is the result of natural selection that has selected the trait because it conferred an advantage to the organism in the past. The other definition of adaptation says that an adaptation is any trait whose absence would be deleterious to the organism, and this means that natural selection is not the only way in which they can arise.

    Sorry for the unconnected ideas :P

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  12. Ok, Ok, Darwin used the term in opposition with Artificial Selection in the original work.

    I take back what i said about it used as opposed to the god will.

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  13. Let's see what happens if we remove the 'natural' term on the first wikipedia articles on Natural Selection.

    It was funny cause it says 'The natural genetic variation'... Why not just 'The genetic variation'? LOL :P
    Also removed the 'natural' word from there.

    It works perfectly. Now, what would avoid the term 'selection' to be equated with 'adaptation' anyways?



    --------------------------------------
    Selection (in biology)

    Selection is the term in biology for the process by which biologic traits become more or less common in a population due to consistent effects upon the survival or reproduction of their bearers. It is a key mechanism of evolution.

    The genetic variation within a population of organisms may cause some individuals to survive and reproduce more successfully than others in their current environment. For example, the peppered moth exists in both light and dark colours in the United Kingdom, but during the industrial revolution many of the trees on which the moths rested became blackened by soot[citation needed], giving the dark-colored moths an advantage in hiding from predators. This gave dark-colored moths a better chance of surviving to produce dark-colored offspring, and in just a few generations the majority of the moths were dark[citation needed]. Factors which affect reproductive success are also important, an issue which Charles Darwin developed in his ideas on sexual selection.

    Selection acts on the phenotype, or the observable characteristics of an organism, but the genetic (heritable) basis of any phenotype which gives a reproductive advantage will become more common in a population (see allele frequency). Over time, this process can result in adaptations that specialize populations for particular ecological niches and may eventually result in the emergence of new species. In other words, selection is an important process (though not the only process) by which evolution takes place within a population of organisms. As opposed to artificial selection, in which humans favor specific traits, in selection the environment acts as a sieve through which only certain variations can pass.

    Selection is one of the cornerstones of modern biology. The term was introduced by Darwin in his influential 1859 book On the Origin of Species,[1] in which selection was described as analogous to artificial selection, a process by which animals and plants with traits considered desirable by human breeders are systematically favored for reproduction. The concept of selection was originally developed in the absence of a valid theory of heredity; at the time of Darwin's writing, nothing was known of modern genetics. The union of traditional Darwinian evolution with subsequent discoveries in classical and molecular genetics is termed the modern evolutionary synthesis. Selection remains the primary explanation for adaptive evolution.

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  14. I think 'natural' in 'natural selection' is omittable. I went to school and universities in clear atheist societies and I cannot remember talking about 'natural selection' when discussing evolution. We called it selection only. 'Natural selection' is more of an ideological term to emphasize an atheistic point of view in general public, not necessary in atheist circles.

    Besides we used the term 'natural selection' in socialist times, too, but rather in an ironic sense. For instance, when the shoes got broken the first time you put them on, you might have called it 'natural selection' to avoid accusing planned economy for this crap.

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  15. I'm an undergrad biology student, and my professors pretty much never say 'natural selection', just selection. 'Natural selection' is a little archaic in scientific circles, though it still dominates in the rest of society.

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