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    01 Feb '19 16:49
    http://science.sciencemag.org/content/363/6426/499

    Three months' time in a dark-sand vs. light-sand environment and the allelic frequency of in the population of mice with light or dark fur was significantly changed.
  2. Subscribersonhouse
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    01 Feb '19 23:181 edit
    @wildgrass

    One more chain against the creationists eh. That link points only to the abstract, I would like to see data on how many generations it takes for the transition from dark to light or Vice Versa, but that was not in the abstract.

    Oh wait, your post says in three months that happens. Wonder how many generations that is? Sounds like maybe ONE?
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    02 Feb '19 08:26
    @wildgrass said
    http://science.sciencemag.org/content/363/6426/499

    Three months' time in a dark-sand vs. light-sand environment and the allelic frequency of in the population of mice with light or dark fur was significantly changed.
    https://www.pbs.org/newshour/science/domesticated-foxes-genetically-fascinating-terrible-pets
  4. Subscribersonhouse
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    02 Feb '19 14:09
    @Metal-Brain
    Sure, first gen domestication doesn't usually work, same with wolves. You can TRY to domesticate a wolf but when you go SIT or some such it just gives you the proverbial finger and does what it wants😉
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    04 Feb '19 18:352 edits
    @sonhouse said
    @wildgrass

    One more chain against the creationists eh. That link points only to the abstract, I would like to see data on how many generations it takes for the transition from dark to light or Vice Versa, but that was not in the abstract.

    Oh wait, your post says in three months that happens. Wonder how many generations that is? Sounds like maybe ONE?
    I have lamented this before but I really wish all these articles could be open access. It's ridiculous that federally-funded researchers who spend thousands of dollars to publish their work then have to keep it behind a paywall.

    The key time point was 3 months, when they sequenced genomes of all these mice to look for frequency changes. If they followed them for longer time frames (14 months) mortality reached nearly 100% in both conditions. My impression is that they purposely applied a severe selection criteria in which the animals had few places to hide from predators. Some of this was just methodological, as it is very difficult to keep wild mice within a defined space.

    Try this link for a laymans write-up: http://science.sciencemag.org/content/363/6426/452
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    04 Feb '19 18:38
    @sonhouse said
    @Metal-Brain
    Sure, first gen domestication doesn't usually work, same with wolves. You can TRY to domesticate a wolf but when you go SIT or some such it just gives you the proverbial finger and does what it wants😉
    really complicated, too. Essentially, you're talking about the evolution of behaviors.
  7. Subscribersonhouse
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    04 Feb '19 19:441 edit
    @wildgrass

    Maybe they could use those shock collars like on dogs but miniaturized......
    A little drone overhead with camera to watch to see they don't exceed boundaries?
    Hey, it could happen😉
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    04 Feb '19 20:03
    @sonhouse said
    @wildgrass

    Maybe they could use those shock collars like on dogs but miniaturized......
    A little drone overhead with camera to watch to see they don't exceed boundaries?
    Hey, it could happen😉
    They created 20,000 m2 enclosures by burying giant steel barriers 2 feet below and 2 meters above the surface of the sand. Then they got rid of all the existing rodents in the enclosure and re-seeded it with animals they had already genotyped, tagged and catalogued.

    GPS tracking 600 wild mice sounds.... logistically challenging.

    This link says the full text is free:

    http://science.sciencemag.org/content/363/6426/499?ijkey=f724fa861093fa4a05da50113514c4ff4dbda641&keytype2=tf_ipsecsha
  9. Standard memberDeepThought
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    @sonhouse said
    @wildgrass

    One more chain against the creationists eh. That link points only to the abstract, I would like to see data on how many generations it takes for the transition from dark to light or Vice Versa, but that was not in the abstract.

    Oh wait, your post says in three months that happens. Wonder how many generations that is? Sounds like maybe ONE?
    The creationists accept microevolution, of which this is an instance, they do not accept speciation, which this does not demonstrate.

    This was observed in Britain in a species of moth in response to the Clean Air Act.
  10. Subscribersonhouse
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    05 Feb '19 15:12
    @DeepThought
    Yeah, I saw that moth study. Did you see how many gens it took for the color change to complete?
  11. Standard memberDeepThought
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    06 Feb '19 13:44
    @sonhouse
    I think this was something the biology teacher told us about at school over 30 years ago - so I don't know much detail. This is predator driven so it depends on predator populations.

    Suppose the white gene is recessive and the black gene dominant. Suppose further that the black gene is the one the current environment favours. Then the population can carry a large number of the white genes as they'll only be expressed when an individual has two of them. Suppose now that the environment changes so that the white gene is now favoured. The switch over can happen quite quickly as there are already plenty of copies of the white gene in the population. The double recessive genotype suddenly has a big advantage and starts to dominate the population. However, if the black gene is selected against strongly enough then it will become extinct - any individual with even one copy will definitely be eaten. So if the environment changes to favour the black gene once again, if there are still carriers of the black gene it will sweep through the population as the white moths get eaten - but if it is extinct a new black gene has to emerge due to a mutation - this acts as a barrier to the emergence of the black phenotype. If the pressure from predation is high enough then the species could become extinct before the new black gene can emerge.
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    06 Feb '19 15:34
    @deepthought said
    @sonhouse
    I think this was something the biology teacher told us about at school over 30 years ago - so I don't know much detail. This is predator driven so it depends on predator populations.

    Suppose the white gene is recessive and the black gene dominant. Suppose further that the black gene is the one the current environment favours. Then the population can carry ...[text shortened]... predation is high enough then the species could become extinct before the new black gene can emerge.
    I don't see why people think this is significant. Color changes have already been proven with selective breeding. The domesticated fox experiments show that it is easy to cause fur color changes even if you are not breeding for it specifically. That is why I brought up the Fox thing.

    Remember my "evolution and life span" thread? I posted an article showing the life span of fruit flies was lengthened by selective breeding. Isn't that a better example?

    Interestingly enough, I tried to look up that article again and stumbled upon another about lithium lengthening their life span as well. Havn't had a chance to read it yet.
  13. SubscriberPonderable
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    06 Feb '19 15:43
    In fact we see "natural selection" in Progress not "evolution".

    In blunt words: There is a gene which encodes colour. This gene as a frequency of occurence in the starting poulation. In the wild the frequnce doesn't Change much. In the Experiment one variant was Chosen over the others (the predators ate the mice with the "wrong" gene and thus only the "right" gene carriers survived and created offspring. So the genetic Setup of the mice was different in frequency and thus "natural selection" (here artificial selection) was seen in Action. As far as the infromation in the article goes they didn't move so far as to wait uintil the "White" gene was eradicated, so we still expect White offspring ow and then. If the Information vanished completely tit is just showing that infromation can vanish which is a virtual non-starter.

    "Evolution in Action" would be if new Information (previously unobserved gene is found) would have been created. That would be as far as this could be proven experimentally. But probably most scientists would agree that the probability for such an occurence and the finding of it would be Minute.
  14. Subscribersonhouse
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    06 Feb '19 20:18
    @Ponderable
    So I would assume it is a feedback system where the eyes of the insect sees the color of the bark it is resting on and the body knows the color of the wings or sees the color of the wings having some contrast deemed dangerous and that starts a chain reaction ending in a genetic change that lowers the contrast to the bark,
  15. SubscriberPonderable
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    07 Feb '19 07:10
    @sonhouse said
    @Ponderable
    So I would assume it is a feedback system where the eyes of the insect sees the color of the bark it is resting on and the body knows the color of the wings or sees the color of the wings having some contrast deemed dangerous and that starts a chain reaction ending in a genetic change that lowers the contrast to the bark,
    The Point is that genetics determine colour for the rodents in the paper originally posted with the sensational Headline. There is no Change of colour in adult animals here (chameleons are different in that respect as are some other specialist species).

    The whole Point is that the experimenters made a Connection between different genetic set-ups resulting in different coloured animals. The infromation however for the colour was there before the Experiment. What they did is to shift (by killing of the animals with the unfavourable colour) the Distribution of the infromation in the whole pool. So they "proved" natural selection. This was not the aim of the Research. The aim was to connect genotype and phenotype.

    My Point is: The authors of the Research paper did some valuable contribution on science with a well done Research paper. The title of the paper : "Linking a mutation to survival in wild mice" is appropriate and tells the Reader what to expect, which is a quite sepcific information.

    The journalists of the paper Scienec went one step wfurther by bringing in their Headline for the Abstract: How natural selection affects mouse coat Color. This is still covered by the paper but not the main Point. "Just" a side effect, which in itself would not have been sufficient to publish the paper at all.

    The title of this thread is using "demonstrating Evolution in real-time" and that is plain wrong. The authors of the Research quite correctly don't make that Claim.

    I tried to state the Facts and try to bring up a criterion which would cover the Headline. That would be the Observation of a new Mutation, which Shows an Advantage and is actually distributed in the gene pool, thus adding infromation to the System.
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