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  1. Naked Science Forum
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  3. Plant Sciences, Zoology & Evolution
  4. Why is natural selection so much slower than human-led selection?
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Why is natural selection so much slower than human-led selection?

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Offline Le Repteux

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Re: Why is natural selection so much slower than human-led selection?
« Reply #60 on: 03/08/2018 15:09:58 »
Quote from: Ophiolite on 02/08/2018 19:00:09
I see very clear parallels that make the two processes analagous. None of that renders correct those assertions of yours I have already contested.
Those assertions derive from what makes the parallel possible, but I think I unnecessary went a bit too far too fast.

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In essence you seem to be arguing for a biological "reality" for memes as do their strongest proponents. I don't think even Dawkins is entirely comfortable with that approach.
Not having gone far enough in the parallel is the only thing I can reproach him, and that also goes for Edelman with his Neural Darwinism. I didn't get that idea directly from them though, but by comparing a theory on motion of mine to the theory of evolution and to what we already know from the way mind works. The general deduction I made and that I'm trying to establish is that nothing can change for good without random inputs. When we move something for instance, its atoms cannot change direction or speed without finding them by essay and error. That's only a different way to consider quantum randomness, and applied to the brain, it becomes a different way to consider imagination. It is not obvious to imagine that our own imagination is so uncertain though, especially for those who have a very good memory, because they have a tendency to rely on what they know instead of taking the risk to try something that has never been tried before. No need for such a good memory to try crazy things though, and it pays sometimes so much when it works that it may be one of the reasons why that kind of evolution is so fast.

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Your comment on expecting to find when we search looks like a nonsensical non-sequitur.
Not if we consider that the way the brain works automatically produces random changes in our thoughts. This way, whether a new idea becomes the norm or not would depend on the environment the same way a mutation does, which means that it is not necessarily because we search in that direction that we will find the answer to the problem. The best way in this case would be to search in many directions at a time, which is equivalent to many individuals carrying different mutations at the same time, and that's exactly what researchers from different teams do, or more generally, what we do when many of us try to imagine a solution to the same problem in the same period of time.
« Last Edit: 03/08/2018 15:23:50 by Le Repteux »
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Offline Le Repteux

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Re: Why is natural selection so much slower than human-led selection?
« Reply #61 on: 03/08/2018 16:46:29 »
Quote from: evan_au on 02/08/2018 22:23:28
Natural selection is a somewhat random process, which means that a beneficial mutation spreads very slowly through a wild population (or may get snuffed out in the first generation).

There is discussion at present about a "gene drive" which will cause a human-made mutation spread exponentially through a wild population. It ensures that more than 50% of the progeny have the gene drive (ie it doesn't obey Mendel's "laws" of inheritance).

Since this could have major impacts on the world's ecology, the inventors have requested a vigorous debate before anyone releases this in the field.
I think a mind drive equivalent to a gene drive might be advertisement: as for the gene drive, it doesn't guaranty the safety of the product, but it certainly spreads the information faster. An evolution process that has randomness as a changing motor has to be progressive, otherwise it may prove dangerous. Since we can imagine absolutely anything, imagination had to come with a propensity to prudence, otherwise it wouldn't have been an improvement.
« Last Edit: 03/08/2018 16:51:33 by Le Repteux »
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Offline Le Repteux

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Re: Why is natural selection so much slower than human-led selection?
« Reply #62 on: 03/08/2018 19:47:24 »
Quote from: Colin2B on 03/08/2018 08:52:30
As has been pointed out, not all evolutionary changes are random, also not all are due to mutation of genes.
To me, whenever we try to introduce something else than randomness at the root of an evolutionary process, we are only trying to find a way for the genes to predict the future, which contradicts the meaning of the process. Fortunately though, if such a way comes from an imagination that also depends on randomness to work properly, the contradiction fades out, and if any change at our scale comes from randomness at the quantum scale, it completely disappears.
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Offline Colin2B

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Re: Why is natural selection so much slower than human-led selection?
« Reply #63 on: 03/08/2018 22:40:37 »
Quote from: Le Repteux on 03/08/2018 19:47:24
...whenever we try to introduce something else than randomness at the root of an evolutionary process, we are only trying to find a way for the genes to predict the future, which contradicts the meaning of the process..
There is nothing in this that suggests genes are predicting the future, they are responding to environmental changes. I’m just pointing out that there are more ways for them to respond than by random mutation.
What makes you think the process has meaning?

Quote from: Le Repteux on 03/08/2018 19:47:24
Fortunately though, if such a way comes from an imagination that also depends on randomness to work properly, the contradiction fades out, and if any change at our scale comes from randomness at the quantum scale, it completely disappears.
I don’t understand this. There is no imagination that depends on randomness, nor any contradiction; invoking the quantum scale changes nothing.
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Offline Le Repteux

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Re: Why is natural selection so much slower than human-led selection?
« Reply #64 on: 04/08/2018 14:47:33 »
Quote from: Colin2B on 03/08/2018 22:40:37
There is nothing in this that suggests genes are predicting the future, they are responding to environmental changes. I’m just pointing out that there are more ways for them to respond than by random mutation.
Nothing can respond to a change immediately, the change in the thing has to be selected by its environment and it takes time. If a change nevertheless happens to a gene and the individual immediately adapts to the change in the environment, I suggest that he gets a lottery ticket right away! :0)

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What makes you think the process has meaning?
The meaning of Evolution is that we are here by chance, and if we extrapolate, it also means that everything is there by chance, even our ideas, reason why I suggest that imagination contains a random process so that our new ideas can be selected by the environment.

Quote from: Colin2B on 03/08/2018 22:40:37
I don’t understand this. There is no imagination that depends on randomness, nor any contradiction; invoking the quantum scale changes nothing.
If everything is here by chance, then any change depends on selection by the environment. When we accelerate a particle, we try to change its direction and/or its speed, and if I'm right with that crazy idea, the resistance it shows should depend on the time it takes to produce the right direction or speed with regard to whatever environment accelerates it, which means that if they are free to move, different particles would take different directions and/or speeds when they are accelerated separately, so that what we observe when we accelerate a body at our scale would only be the result of a random/selection process at the particles' scale similar to the mutation/selection one. Of course, what I say implies that my idea is a random try, and that only the environment can tell if its direction has any sense. For the moment, the environment is all those who are observing the thread, including you, so from 0 to 10, what is your score? :0)
« Last Edit: 04/08/2018 22:57:07 by Le Repteux »
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Offline evan_au

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Re: Why is natural selection so much slower than human-led selection?
« Reply #65 on: 05/08/2018 12:13:14 »
Quote from: Le Repteux
Nothing can respond to a change immediately, the change in the thing has to be selected by its environment and it takes time. If a change nevertheless happens to a gene and the individual immediately adapts to the change in the environment, I suggest that he gets a lottery ticket right away! :0)
In any population, random genetic change occurs all the time.
- Some mutations will be an advantage in their current environment, and be positively selected
- Some will be a disadvantage in their current environment, and be negatively selected
- Some will be neutral in their current environment, and not feel any explicit selection pressure (but will still be exposed to random impacts from the genes it is closely associated with).
- Many mutations will be recessive, and will have little or no impact unless an individual ends up with 2 copies of the recessive gene

However, it is possible that at some future date, the environment changes such that a previously neutral or recessive gene becomes a significant advantage to those carrying it (eg making the carrier immune to some novel pathogen that appears in the environment).

In this case, evolution has "predicted the future" simply by maintaining significant genetic diversity and keeping the options open for this species, which allows this species to withstand a future environmental challenge. In this case, the species has "won the lottery".

One of the difficulties in protecting a critically endangered species is that there is very little genetic diversity left in the population, and they could all be wiped out by a subtle change in the environment.
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Offline Le Repteux

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Re: Why is natural selection so much slower than human-led selection?
« Reply #66 on: 05/08/2018 15:36:33 »
Quote from: evan_au on 05/08/2018 12:13:14
In this case, evolution has "predicted the future" simply by maintaining significant genetic diversity and keeping the options open for this species, which allows this species to withstand a future environmental challenge. In this case, the species has "won the lottery".
I have a problem with the english language definition of "prediction". In french, a prediction refers to Nostradamus, so it means "very improbable", whereas in english, and especially in science, it also refers to the constancy of an observation, to a proven fact, which is exactly the contrary. Associating the word prediction and the word lottery like you do can thus be misleading. In english, a scientific mechanism based on randomness cannot predict the future, so it is only by chance if the right mutation is still there after a long time. If we go on using the word prediction this controversial way, I predict that the mutation/selection principle is going to loose all its original sense in no time, because it is a proven fact that it has already begun to lose it. :0)

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One of the difficulties in protecting a critically endangered species is that there is very little genetic diversity left in the population, and they could all be wiped out by a subtle change in the environment.
Right, now allow me to apply that principle to the way I think my imagination works. I never heard anybody say that mind may produce randomness the way mutations do, so I'm probably the only one to have that idea now, and I didn't convince anybody to study it yet, so it means that, like a mutation that falls in an environment that hasn't changed, my idea may also be lost even if it is right. One of the ways to check if that idea makes sense is to compare it to evolution of species like I just did. If you have time, try to give me an example where you think that the two kinds of evolution would not work the same.
« Last Edit: 05/08/2018 15:53:40 by Le Repteux »
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Offline evan_au

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Re: Why is natural selection so much slower than human-led selection?
« Reply #67 on: 06/08/2018 12:16:56 »
Quote from: Le Repteux
Associating the word prediction and the word lottery like you do can thus be misleading.
Another way of looking at it is that a species with a lot of genetic diversity has bought a lot of tickets in the future, which often looks like a lottery to us.
That genetic diversity increases the chance that they will hold a winning ticket (or at least a minor prize).

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mind may produce randomness the way mutations do
In the young mind, neurons are connected randomly to other neurons.
However, as each critical phase of development occurs, connections that don't produce a significant correlation get pruned, leaving a much smaller set of neural connections.

Effectively, a process of "survival of the fittest" determines which neural connections will be retained and which will be lost, based on the environmental exposure leading up to this pruning phase.
If I understand the mechanism, this pruned set of connections then provides the neural inputs to the pruning of the next level of neurons, at the next stage of development.

By this mechanism, an infant becomes adjusted to their environment, even if that environment is quite different from the environment in which their parents grew up.

See: https://en.wikipedia.org/wiki/Synaptic_pruning
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Offline Le Repteux

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Re: Why is natural selection so much slower than human-led selection?
« Reply #68 on: 06/08/2018 15:16:37 »
Quote from: evan_au on 06/08/2018 12:16:56
Another way of looking at it is that a species with a lot of genetic diversity has bought a lot of tickets in the future, which often looks like a lottery to us.
That genetic diversity increases the chance that they will hold a winning ticket (or at least a minor prize).
Yes, and this genetic diversity rule also applies to individuals: it must be there in case the environment changes, but it must not prevent the specie to stay the same if no change happens in the environment. If too many individuals would carry too important genetic defects, as it might be the case one day for chemical pollution for instance, the specie might be in danger.

Quote from: evan_au on 06/08/2018 12:16:56
a process of "survival of the fittest" determines which neural connections will be retained and which will be lost, based on the environmental exposure leading up to this pruning phase.
Good point that shows how randomness can be useful to the mind, but the randomness I'm talking about is different, it is a short term one that affects each of our ideas separately. It happens when we are simulating a new solution to a problem in our own mind, thus when we imagine a solution. We can then virtually picture something and rotate it in our mind, change its direction or speed, change its color or its weight, or anything we want, and nothing is already planned. If I ask you to picture a number without thinking, any number you want between 1 and 100, what exactly tells you to pick up the one you are going to picture? Nothing, which means it is unpredictable, which means it is random. The environment is not random for you since it is represented by me that is asking you, but my question is random for you and your answer is random for me since both are unpredictable for each of us. Whether my question will be accepted, thus selected by you, or your answer will be accepted, thus selected by me, is another analogy we can make with the mutation/selection principle: it is similar, but not exactly the same. The selection of our ideas, that we can call a social selection, can change sides, so it is more subtle than for the species' one, but more importantly, it is a lot faster.

We know that randomness can be artificially produced, so what I suggest is that the brain can produce some. If it was a random routine like a computer one, we could consider it is artificial, but I suggest it is more general, I suggest it happens all over the mind and it is due to the way our memory works. I suggest it is due to the neurons not being able to reproduce their pulses with an absolute precision, so that each small imprecision at the neurons' scale would add up and finally make an observable one at the scale of our ideas. There is probably also a place in the brain where mind selects its own ideas, so that when we think or when we sleep, our new ideas, that then wander without external interaction, can follow a logical path even if they are often completely unrealistic.
« Last Edit: 09/08/2018 14:59:14 by Le Repteux »
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Offline gwynhefar

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Re: Why is natural selection so much slower than human-led selection?
« Reply #69 on: 05/10/2018 19:28:17 »
To get back to the original topic, natural selection is slower than human breeding because there's no 'mind' or 'purpose' behind natural selection.  A random mutation turns out to be useful, so more of the animals with that mutation survive to have offspring and live long enough to bear young multiple times, and the number of animals with that mutation in the overall population slowly grows until it becomes widespread.

Human breeding of animals, however, is purpose-driven.  We decide which traits we want and then take individuals with those traits and force them to breed together (whereas in the wild they might not even have met) to increase the chances that the offspring have the trait.  There are entire calculations and strategies on the best way to mold a trait through selective breeding.
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Offline Le Repteux

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Re: Why is natural selection so much slower than human-led selection?
« Reply #70 on: 06/10/2018 15:25:26 »
Quote from: gwynhefar on 05/10/2018 19:28:17
To get back to the original topic, natural selection is slower than human breeding because there's no 'mind' or 'purpose' behind natural selection. A random mutation turns out to be useful, so more of the animals with that mutation survive to have offspring and live long enough to bear young multiple times, and the number of animals with that mutation in the overall population slowly grows until it becomes widespread.
Hi Gwynhefar,

I think that our brain works the same as natural selection to concoct new ideas: I think that chance breeds some of our ideas, and that random changes also happen to them. Nevertheless, I think that our ideas evolve faster than species because our brain works faster, and because it takes us less time to experiment a new idea than nature takes to experiment a new individual. In this sense, breeding animals to enhance a particularity is only experimental, which is supported by the fact that, most of the time, enhancing a particularity also enhances a genetic defect that affects the survival of those animals. In reality, it is not to help them that we do that, but to help us. If we tried to improve their survival for instance, we wouldn't be any luckier than we are when we try to improve ours, and for the moment, nothing shows that we are going to survive any longer than any other specie.
« Last Edit: 09/10/2018 15:53:09 by Le Repteux »
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