But can we distinguish things as artificial and natural by the initial state as "active thought"? — Christoffer

Just so, it is a pragmatic distinction but no longer absolute; one has to allow a degree of arbitrariness in claiming a significant difference between a straw hut and a bird's nest. and one would have by your criterion of active thought, to go along with the idea that sexual selection is artificial selection - the peacock's fan being the result of the peahen's choice, as @StreetlightX argues above, as is the weaver bird's nest building, although that seems also to have natural component.

Where the distinction becomes really unhelpful though would be in trying to work out whether or not a termite mound is or is not the product of a group mind, termites functioning as neurone-analogues.

But personally, I am quite sympathetic to maintaining the now arbitrary distinction as natural/man-made, as peasants do, bouyed by tradition. and then peacock feathers are natural, unless they are made of plastic.

Now folks that want to manage without God have a problem, which has been pointed out here, that Man and Nature, or artificial and natural, collapse as man is part of nature sans god. And such a collapse deprives 'nature' of any meaning, because it deprives it of any negative. If there is nothing that is unnatural, then 'natural' means the same as 'everything'. But this is a purely linguistic phenomenon, and non-philosophers are happily immune from such vandalism of useful words and continue to use 'natural' in contrast to 'man-made', and trust that god has provided an appropriate hell for philosophers. — unenlightened

Rejecting God or any diety is easy. But as you say, what is exceptionally hard for many people is the difference between "man" and "nature" as obviously humans are part of nature too, so there's no justification for humans to be different anymore. Yet then comes all the normative baggage of what we "as humans" ought to do "to the environment" and how we ought to live. Atheist aren't willing to give up the exceptionality of humans, sometimes they promote it even more.

Of course, one simple solution is to define anything that is found in nature absent of man making it is natural and what man has made is synthetic/artificial or man made, opposite to "natural". Like there aren't many personal computers found in any natural environment where humans haven't been, even if the raw materials that it is made of can be found.

OK, we went astray a bit, because I didn't envisage this discussion to be primarily about defining clear cut difference between artificial and natural, selection, production, processing, or any other kind of acting in general. I wanted to emphasize that for evolution, it doesn't matter who or what produces selective pressure: human, monkey, virus, or a climate change due to a fallen meteorite. These are all natural agents, their rationality is irrelevant, and there is no reason to single out man as something different, or unnatural, as Darwin actually did, when he theorized about the difference between natural and artificial selection. This is not linguistic objection, it is more essential than that.

These are all natural agents, their rationality is irrelevant, and there is no reason to single out man as something different, or unnatural, as Darwin actually did, when he theorized about the difference between natural and artificial selection. — Hrvoje

No, you still don't understand Darwin's argument - maybe if you actually read the book where he introduces his terms, you would see where he was coming from. That selection practiced by a sheep breeder or a horticulturalist on the one hand, and by non-anthropogenic environmental factors on the other hand - both resulting in differential reproduction - was rather his point - a point that would not be immediately obvious to his readers. So he starts by describing something his readers would be well familiar with - what he calls Man's selection or artificial selection, offers an explanation for it, and then proceeds to apply that same explanation to other forms of selection that had been in operation on Earth long before sheep breeders and horticulturalists.

Rejecting God or any diety is easy. — ssu

Is it really so easy? The word "selection" implies choice, and choice requires an agent who is doing the choosing. In the case of "natural selection", if the agent who is doing the choosing is not God, then who is it, Mother Nature? It appears to me that as long as we maintain the concept of "natural selection", some sort of God or deity is implied as that which is doing the selecting.

Wouldn't it better serve the purpose of evolutionary theorists, to remove the word "selection" from the description of the natural processes which are related to death? We all die and there is no selection (by the grim reaper) involved. Then "selection" is left to describe the reproductive processes, like those described by StreetlightX, which are responsible for the continuity of existence. There really is no need for a concept of "natural selection".

But it would fall in the realm of natural selection on any sensible reading of Origins, where sexual selection is a paragraph within the Chapter on natural selection. The title of the book is a dead give away as well, which, if sexual selection was a thing apart would've been in there. It's not as if he was trying to be brief with the title, which reads in full : On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life.

I haven't read Descent, so quite possibly Darwin had a change of heart but then I still have a conceptual problem with the distinction. How are aesthetics in natural selection separate? Time and again it is established that what we find aesthetically pleasing in mates has everything to do with survivability (hips and tits as a sign of fertility, strength for virility and protection). And even if we couldn't link it to survivability it's not as if it wouldn't become just another selective pressure that has no intentionality whatsoever as I don't control who I'm attracted too. If we did, the religious could rejoice and start "curing" gay people.

I think the distinction is a bit meaningless anyway. It's not clear what sort of human behaviour is no longer natural but artificial. Or at what point natural behaviour produces an artifact. Monkeys using a branch, tearing of leaves and twigs to make a stick, to reach ants in a tree bark made an artifact out of the branch. Or possibly not. It depends on your definition, which is a bit arbitrary. — Benkei

What does one mean by ''artificial'' then?

I'm no linguist but ''artificial'' was probably invented to distinguish human activity from the rest of nature. We do stuff to the world, like inventing machines, which no other animal, save some chimps, can do. It's a worthwhile distinction to make - human artificial and the rest natural.

The catch is creating the artificial comes naturally to us.

If you step back far enough then everything is like everything else and you are staring at one featureless mass. As you note yourself it's no use insisting that everything is "natural"; this isn't any more meaningful than clearing your throat.

There are advantages to stepping back some way and looking at ourselves and our purposeful activity, such as building dwellings - and yes, breeding sheep - as being a kind of ecological adaptation in itself - and thus being a part of the same dynamics that is exhibited in the "natural" world. But so too there are advantages to stepping closer and distinguishing different varieties of selective pressures and adaptations. And of course in appropriate contexts there are any number of reasons for distinguishing "man-made" from "natural."

Artificial selection indicates sexual selection where the reproductive choices are made by man rather than the pigeon, or the sheep. So artificial selection is a subset of sexual selection - in contrast to natural selection, which is concerned with surviving long enough to breed.

Do you think Darwin was mad when he titled his second book: 'The Descent of Man' - given that evolution is generally speaking, a process of weeding out, shouldn't it be: 'The Ascent of Man'?

Or do you suppose he coined the phrase in relation to the religious idea of Creation at the beginning of time, that implies a descent from the ideal into corruption?

With regard to the human species, as the only intellectually intelligent animal, I think it important to stress the direction of knowledge over time, from less and worse, toward more and better.

Yet the reception of Darwin's works by a religious world, ranged from muted to outraged via outright mockery. So maybe he was angry when he chose the term 'descent.'

Is it really so easy? The word "selection" implies choice, and choice requires an agent who is doing the choosing. In the case of "natural selection", if the agent who is doing the choosing is not God, then who is it, Mother Nature? It appears to me that as long as we maintain the concept of "natural selection", some sort of God or deity is implied as that which is doing the selecting. — Metaphysician Undercover

A bit off from the subject, but for an atheist it's quite easy. And in the process of "natural selection" you really don't need God, when you have a random process how species get their genes and then the process of those most adapted to the environment making more offspring. The result isn't the best or optimal, but just a result. First and foremost, Darwinism is part of science, not an ideology, and hence it's based on objective study. More of a need for God would be to answer moral questions, what is wrong or right, but atheists typically just refer to humanism in this case.

As I said, it really depends on your definition where to put the line between natural and artificial and that is arbitrary. Artificial is meant as "man made rather than occuring naturally". My issue with that, is that anything man made is natural in my view. Perhaps it's easier to just do away with "artificial" and simply say man-made as something understood as a more specific process found in nature.

A bit off from the subject, but for an atheist it's quite easy. And in the process of "natural selection" you really don't need God, when you have a random process how species get their genes and then the process of those most adapted to the environment making more offspring. — ssu

But a random process is not a selection. When you toss a coin do you think that something selects whether heads or tails will appear?

First and foremost, Darwinism is part of science, not an ideology, and hence it's based on objective study. More of a need for God would be to answer moral questions, what is wrong or right, but atheists typically just refer to humanism in this case. — ssu

Science is an ideology, a methodological ideology, but that's irrelevant. Darwin had to select the words used in description of his theory, and the fact is that he used "selection". If you explain what Darwin called a "selection", as a random process, then clearly you are misinterpreting what Darwin intended. He meant, that nature selects from processes which would, without such selection, produce random results. So you cannot dismiss as non-essential to his theory, that act of selection, leaving the whole thing as random processes. "Selection" does not mean random.

As I said, it really depends on your definition where to put the line between natural and artificial and that is arbitrary. Artificial is meant as "man made rather than occuring naturally". My issue with that, is that anything man made is natural in my view. Perhaps it's easier to just do away with "artificial" and simply say man-made as something understood as a more specific process found in nature. — Benkei

But Darwinian evolutionary theory breaks down the division between human beings and other animals. So to divide between artificial and natural, along the lines of human vs. all else, is not justified or supported by any real principles. This means we need to either extend the class of "artificial" to include the activities of other living beings, or else dismiss it altogether leaving everything as "natural".

Time and again it is established that what we find aesthetically pleasing in mates has everything to do with survivability. — Benkei

Unfortunately, this is not true. Or rather, for quite a while its been thought to be true, but has begun to crumble under large swaths of emerging evidence that it simply does not account for a great deal of evolutionary phenomena. Ascribing 'what we find aesthetically pleasing in mates to survivability alone' simply flies in the face of evidence - Prum, the Yale ornithologist who I'm relying upon here - cites case after case after case (from the wings of Manakins, to the reproductive systems of ducks, the displays of the great Argus, and so on) where attempts to account for aesthetic phenomena in terms of survivability simply does not work. The evidence itself needs to be read to be discussed, so I can only encourage that you read his work. None of this is to say that what we find aesthetically pleasing in mates has nothing to do with survivability. Only that survivability does not exhaust accounts of aesthetic phenomena.

And even if we couldn't link it to survivability it's not as if it wouldn't become just another selective pressure that has no intentionality whatsoever as I don't control who I'm attracted too. If we did, the religious could rejoice and start "curing" gay people. — Benkei

This, though, is a non-sequitur through and through. The whole question of intentionality is an irrelevancy - the question is simply: is sexual selection an independent evolutionary mechanism to natural selection, yes or no? Is mate choice a driver of evolutionary change in its own right, or not? Whatever the 'metaphysics' of 'choice' at work here is irrelevant. Ironically, one of the reasons sexual selection was so violently rejected as an independent evolutionary mechanism in the time after Darwin theorized it was because the very idea that animals - specifically females! - could play any causative role in driving evolution was nothing less than an offence to Victorian puritan mores. That same regressive hangover remains an infection on our understanding of evolution today.

As I said, it really depends on your definition where to put the line between natural and artificial and that is arbitrary. Artificial is meant as "man made rather than occuring naturally". My issue with that, is that anything man made is natural in my view. Perhaps it's easier to just do away with "artificial" and simply say man-made as something understood as a more specific process found in nature. — Benkei

This insistence on everything being natural is a self-inflicted semantic confusion. The point being made is silly: everything is natural, because nature is everything, by definition. This does not say anything meaningful, it's just a tautology. Yeah, I get it, you don't believe in gods and the supernatural. If that's what you want to say, then say it (though why you would want to bring that up in the present context - I have no idea). But why do violence to language?

Per the online etymology dictionary, the "literal" definition of "unnatural" is "not in accord with physical nature," where the etymology of "nature" is wrapped up with "life"/living things from the start. Per that, everything would be natural.

In the early 1500s, we see a usage of "unnatural" a la "at variance with moral standards," and the "artificial" sense apparently doesn't pop up until the mid 1700s.

This, though, is a non-sequitur through and through. The whole question of intentionality is an irrelevancy - the question is simply: is sexual selection an independent evolutionary mechanism to natural selection, yes or no? — StreetlightX

As far as a particular gene/genome is concerned, the source of the selective pressure is of no consequence: it is the same heritable variation/selection mechanism. Of course, from a wider perspective of a species there is a difference.

What accounts for the difference? In the simple Darwinian scenario the environment - and thus the fitness landscape - is fairly stable, and the population either adapts to it gradually, through successive generations, or goes extinct. However, in the case of sexual selection the fitness landscape is not only dynamic, its evolution is tightly coupled to the evolution of the population genome. This is now a very different game.

Those who studied the basics of partial differential equations may be familiar with a variant of the following problem. An island is populated by goats and wolves. Goats eat grass, wolves eat goats. The populations of grass, goats and wolves grow or shrink in response to the availability of food and/or predation. This can be modeled by a system of coupled partial differential equations. The model is so ridiculously simple that it actually has an exact analytical solution (a rare thing in real-life modeling). And yet even this extremely simple setup gives rise to an interesting dynamics in the phase space, with loops, spirals, regions of stability/instability and tipping points. The reason for this complicated dynamics is the mutual dependence of processes that make up the toy model.

And now imagine something similar in principle, but hugely more complicated - that is what the dynamics of sexual selection is like. But not just sexual selection: similar antagonistic evolution results in arms races between males of the same species
or between predators and prey.



From the naive point of view such antagonistic evolution is counterproductive: wouldn't it be better if we could all get along instead of wasting resources on pointless competitions? Make love not war! But of course nature doesn't care about such "commonsense" sentiments: it just does what it does for no reason at all.

From the naive point of view such antagonistic evolution is counterproductive: wouldn't it be better if we could all get along instead of wasting resources on pointless competitions? Make love not war! But of course nature doesn't care about such "commonsense" sentiments: it just does what it does for no reason at all. — SophistiCat

Heh, I wouldn't say 'no reason at all', but rather, for more interesting and varied reasons than we are usually prepared to countenance. For sexual selection in particular, the generally agreed upon mechanism is that of 'runaway selection', where, while (aesthetic) features might have initially begun to be selected for as signs of better fitness, as those features become more prominent over evolutionary time, they become more and more desirable for their aesthetic qualities alone. In other words, runaway selection creates positive feed-back loops which become autonomous and independent of the dynamics of natural selection (within certain threshold boundaries of course).

Such runaway processes have also been invoked to explain the emergence of cooperation and altruism among certain species (us!) where one would expect a more dog-eat-dog world. It's not all sunshine through - as Prum notes, in the case of ducks, such runaway processes have led to an intra-sexual 'arms race' where male and female ducks have evolved some terrifying genitalia because male ducks are, well, very rapey, and female ducks have literally evolved different genitalia in order to stop being impregnated by male ducks they don't want to be impregnated by. Nature is scary and wildly facinating.

I agree that sexual selection is form of, or result of intraspecific competition, and as such does not need to be singled out, regardless of the question how much esthetics and fitness correlate. That is just another argument pro my proposition.

Although it may be a result of cooperation, not neccesssarily adversarial competition.

You're a naturalist? How so? Do you walk around naked? — karl stone

That is a naturist, not a naturalist.

The syntagm "Natural Selection" in Darwin's theory is redundant in a sense that the word "Natural" could/should be omitted, as there is no alternative to nature when we talk about reality, ie not imaginary processes but real processes. — Hrvoje

The work done by the word 'natural' in 'natural selection' is to indicate that the selection is not done by a conscious being who says 'we'll have this one instead of that one'. With that meaning, there is no redundancy. It's a different meaning of 'natural' from the one you envisaged.

A more accurate alternative would be 'unconscious selection' or 'accidental selection', but they don't sound as good.

This, though, is a non-sequitur through and through. The whole question of intentionality is an irrelevancy - the question is simply: is sexual selection an independent evolutionary mechanism to natural selection, yes or no? Is mate choice a driver of evolutionary change in its own right, or not? Whatever the 'metaphysics' of 'choice' at work here is irrelevant. Ironically, one of the reasons sexual selection was so violently rejected as an independent evolutionary mechanism in the time after Darwin theorized it was because the very idea that animals - specifically females! - could play any causative role in driving evolution was nothing less than an offence to Victorian puritan mores. That same regressive hangover remains an infection on our understanding of evolution today. — StreetlightX

How so? Darwin dinstinguishes artificial selection from natural selection by pointing to human intentionality. Based on that distinguishing feature, sexual selection would fall within the scope of natural selection. I also don't see how sexual selection falls outside of the four principles of natural selection. Obviously, I'm reading a bit on this left and right and the easily accesible sources describe sexual selection as a mode of natural selection as well. Also, see andrewk's commenton "accidental selection"; it is in that sense relevant whether there's intentionality or not. At least in my view.

Also, I'm wondering whether we're really saying different things. You quoted someone calling sexual selection the handmaiden to natural selection where my original comment concerned the juxtaposition between artificial selection and natural selection (which Darwin makes in his origin of species) and the claim that instead Darwin was comparing/juxtaposing sexual selection and natural selection that I disagreed with.

I don't agree it's either confusion or violence to language. I don't like the word "artificial" (or "natural" for that matter) for the reason that it is often quickly followed by appeals to nature and the like. I try to avoid such terms as much as possible as a result. It's also not that I do not understand what people try to convey or that it's necessarily wrong, I just think - as in this case - there are better and clearer terms.

You quoted someone calling sexual selection the handmaiden to natural selection — Benkei

To be fair, I didn't quote anyone! That said, I was implicitly responding to this:

I'm certain sexual selection is a mode of natural selection. — Benkei

- the wording of which I mirrored in my first post here ("sexual selection is not a mode of natural selection"). Perhaps the issue can be put like this: if one wants to conceive sexual selection as a mode of natural selection, this can be done, but only at the price of broadening the the concept of natural selection so that it loses its specificity. To put the problem crudely, if you conflate sex and death as sources of selective pressure (so as to lump them both under the label 'natural selection'), you lose the ability to properly conceptualise the evolutionary dynamics specific to each.

And that's the key point: sexual selection and natural selection can lead to divergent evolutionary outcomes. Specifically, sexual selection can make a species less than optimized to its environment, making it evolutionarily worse-off than it otherwise would be. This is why runway selection is such a big deal: once selection starts to occur due to aesthetic criteria (rather than criteria of pure survivability), you get a divergence in selective parameters, as it were. You get two dimensions along which to measure evolutionary success, each of which can, depending on the situation, complement or conflict with each other.

Now of course one can just ignore all of this and say 'its all natural selection', but then this would be like trying to parse a fine-grained phenomenon with a knife too large to do the job. You would not capture the specificity of the dynamics at a resolution appropriate to it. If you don't make the distinction, and make it well, you deprive yourself of the ability to properly understand certain evolutionary phenomena.

--

As for the OP, we probably agree. The whole thing hinges on a very silly understanding of what is implied by 'natural' in 'natural selection'.

And that's the key point: sexual selection and natural selection can lead to divergent evolutionary outcomes. Specifically, sexual selection can make a species less than optimized to its environment, making it evolutionarily worse-off than it otherwise would be. This is why runway selection is such a big deal: once selection starts to occur due to aesthetic criteria (rather than criteria of pure survivability), you get a divergence in selective parameters, as it were. You get two dimensions along which to measure evolutionary success, each of which can, depending on the situation, complement or conflict with each other. — StreetlightX

This apparently even happens with what you consider natural selection sans sexual selection. Monkeys who like unripe fruit which is more difficult to open the less ripe it is so only the strongest monkeys can open the really hard ones. Only to die from poison.

Monkeys who like unripe fruit which is more difficult to open the less ripe it is so only the strongest monkeys can open the really hard ones. Only to die from poison. — Benkei

But the only selection criteria at work here is death: the strength of the monkey isn't relevant. Natural selection is 'indifferent' to how you die; only that you die is relevant.

In the coming apocalypse, our cockroach brethren are far more likely to be far better suited to the wasteland than we are, for all our apparent gifts.

Heh, I wouldn't say 'no reason at all', but rather, for more interesting and varied reasons than we are usually prepared to countenance. — StreetlightX

Yeah, I didn't mean to imply that it's completely random and chaotic; of course there are reasons - they just aren't the obvious reasons that we like to attribute to nature.

Nature is scary and wildly facinating. — StreetlightX

It sure is. One of the more disturbing instances of antagonistic evolution is the struggle between the mother and the offspring. The (future) offspring wants to suck in as many nutrients as it can, grow as big as it can, but the mother wants to ration her considerable investment of resources more prudently, so that she has more chances to reproduce (starting with surviving the childbirth). It's hard to wrap your mind around the fact that this struggle takes place inside one and the same organism!

the question is simply: is sexual selection an independent evolutionary mechanism to natural selection, yes or no? — StreetlightX

It's not such a cut and dried question. On the one hand, there are distinctions between different types of selection, sometimes very obvious ones. On the other hand, the reason Darwin ultimately set sexual selection apart from natural selection may have to do with the fact that he tended to think about natural selection as survival of the fittest (even if he didn't coin that phrase). Later thinkers amended that formula as differential reproduction of the fittest - not as snappy, but more in keeping with the thrust of the theory. Dying before reproducing and surviving but failing to reproduce have exactly the same effects on fitness. Put that way, sex - reproduction - has everything to do with natural selection. Again, I am not a "lumper" - I don't believe that everything is the same as everything else and all distinctions are meaningless; but selection categories are not as starkly distinct as some make them out to be.

Unfortunately, this is not true. Or rather, for quite a while its been thought to be true, but has begun to crumble under large swaths of emerging evidence that it simply does not account for a great deal of evolutionary phenomena. Ascribing 'what we find aesthetically pleasing in mates to survivability alone' simply flies in the face of evidence - Prum, the Yale ornithologist who I'm relying upon here - cites case after case after case (from the wings of Manakins, to the reproductive systems of ducks, the displays of the great Argus, and so on) where attempts to account for aesthetic phenomena in terms of survivability simply does not work. The evidence itself needs to be read to be discussed, so I can only encourage that you read his work. None of this is to say that what we find aesthetically pleasing in mates has nothing to do with survivability. Only that survivability does not exhaust accounts of aesthetic phenomena. — StreetlightX

Whatever the 'metaphysics' of 'choice' at work here is irrelevant. Ironically, one of the reasons sexual selection was so violently rejected as an independent evolutionary mechanism in the time after Darwin theorized it was because the very idea that animals - specifically females! - could play any causative role in driving evolution was nothing less than an offence to Victorian puritan mores. That same regressive hangover remains an infection on our understanding of evolution today. — StreetlightX

I can see where some of the negative reaction to Prum's book may be coming from. I haven't read it, but I have seen some of the media reporting, like this New York Times piece: How Beauty Is Making Scientists Rethink Evolution. One can easily recognize a familiar narrative: a maverick scientist bravely challenges the dogma, only to be met with outraged howls from hidebound academia. And this precious flourish about "Victorian puritan mores" is a topping on the cake.

Only there seems to be something wrong with this story, starting with the subtitle of the book: "How Darwin's Forgotten Theory of Mate Choice Shapes the Animal World - and Us." Now wait a minute, Darwin's theory of sexual selection was never forgotten or abandoned, as Prum claims (judging by the reporting that I have seen). Challenged, modified, developed - yes. It is true that Alfred Wallace, Darwin's younger colleague and the co-discoverer of the theory of evolution, was skeptical about the role of female preference, but the idea that female preference is one of the most important drivers of sexual selection has been the received view since at least Ronald Fisher's 1930 hugely influential work on population genetics (he was the one who introduced the idea of "runaway" evolution in connection with sexual selection). Yes, purely adaptationist explanations of sexual selection have been put forward (starting from Darwin himself), and, as it often happens, some scientists tried to put all their chips on that idea, but it never became the mainstream dogma. For example, one idea that gained some popularity, which is that females choose bizarre and maladaptive male traits precisely because they are maladaptive (a male who thrives in spite of the handicap must be very strong indeed) has been extensively criticized, including by Dawkins in The Selfish Gene.

It sure is. One of the more disturbing instances of antagonistic evolution is the struggle between the mother and the offspring. The (future) offspring wants to suck in as many nutrients as it can, grow as big as it can, but the mother wants to ration her considerable investment of resources more prudently, so that she has more chances to reproduce (starting with surviving the childbirth). It's hard to wrap your mind around the fact that this struggle takes place inside one and the same organism! — SophistiCat

I still hear claims that organisms reproduce "for the good of the species" or similar utterances, which is pretty amazingly wrong. Organisms reproduce for the sake of their genes, a selection process which sometimes even bumps up against the genetic interests of of their own offspring (and siblings, to say nothing of their unrelated conspecifics).