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    Is there any evidence of good mutations that have been passed on to the next generation and give a selective advantage?
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    (Original post by Lil08)
    Is there any evidence of good mutations that have been passed on to the next generation and give a selective advantage?
    Yes. For example if you look at headlice, many lice have a mutation that renders them resistant to anti-lice treatments e.g. permethrin, therefore these lice survive and pass on their genes to future generations.

    Same goes for Staphylococcus Aureus, certain bacteria have a mutation in their genetic code that allows them to resist antibiotics e.g. Methicillin. These therefore survive and pass on these favourable genes leading to MRSA.

    Another good example is Sickle Cell Anaemia which is a result of a haemoglobin mutation that makes the individual more resistant to malaria. Thus having/carrying sickle cell anaemia in Africa is advantageous.
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    (Original post by Democracy)
    Another good example is Sickle Cell Anaemia which is a result of a haemoglobin mutation that makes the individual more resistant to malaria. Thus having/carrying sickle cell anaemia in Africa is advantageous.
    Just a small point, the gene responsible for Sickle Cell Anaemia is recessive, if you have just one copy of the gene you will not develop Sickle Cell Anaemia however you will show resistance to malaria. Having two copies means you will have the disease, which is much worse than malaria.
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    Isn't there a man who is resistant to HIV due to a mutation (of his lymphocytes? Wild guess, right thurr.)
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    Considering the fact that living things came into existence by means of natural selection there should be countless examples, right?
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    perfect blood giving you a perfect immune system?!?!
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    (Original post by Lil08)
    Considering the fact that living things came into existence by means of natural selection there should be countless examples, right?
    Indeed, it really is countless. So much so that even beginning to document them all would be insanely complicated.
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    Bearing in mind that such events take place over many generations we can only see them happening in organisms with generations much shorter in time than ours which is why most examples are in organisms such as bacteria.
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    (Original post by The_Octopus)
    Bearing in mind that such events take place over many generations we can only see them happening in organisms with generations much shorter in time than ours which is why most examples are in organisms such as bacteria.
    Also a human is so much more complex it's far harder to isolate individual mutations and figure out what effects they have.
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    First ones that come to mind have already been mentioned, such as bacterial antibiotic resistance and sickle cell malarial resitance.

    Also the oft cited peppered moth, that changed it's colouring to suit the increasing industrialization cuasing soot covered trees.

    Essentially, almost everything you can think of that's good about a present day organism was once upon a time a beneficial mutation that was passed along.
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    (Original post by Get Cape.Wear Cape.Fly.)
    Isn't there a man who is resistant to HIV due to a mutation (of his lymphocytes? Wild guess, right thurr.)
    There is more than one person with a heightened resistance to HIV, did you by any chance watch a tv documentary which followed the man in question? The resistance occurs due to a mutation in the CCR5 gene, causing the person to possess less CCR5 receptors with which the HIV binds
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    I seem to remember from A level Biology that certain arctic foxes passed on a thicker hair gene that allowed some to survive better than others, and vice versa for when the temperature rose.

    Strage connection, but, what about the fact that scientifically beautiful people tend to pair up with similarly attractive people. These people due to their looks and socially accepted 'beautiful' faces if you will are encouraged at a young age to understand they are attractive and often cooed at and able to get their own way. They then become the popular, out going people at school and highschool that take part in extra curriculars, become well rounded and somewhat well educated. From there and whatever route they take their confidence and charm allows them to have sucsessful, highly paid jobs. The flipside is that the unattractive genes are spread amongst equally unnattractive people who due to a mix of low confidence levels and intelligence take menial jobs and so the saga coninues.

    This theory is meant to take place over many many years, but what do you think? I guess it is less of a mutation in the 'spontaneous changing of an allele/gene causing a random, new characteristic' more in the progressive continuation of genes that lead to sucsess of that species. Sucsess meant within reason for that species- I.e. The peppered moth was able to continue more sucsessfully because it wasn't as predated on by predators, the arctic fox surviving winters more comfortably, potentially humans having a better quality of life?
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    I would say that resistance to disease is the most important proof of this.
    Assuming you have a population of bacteria that can be killed by chemical A but a few have a mutation that makes them resistant (and in this example weaker than the rest of the species). Without the introduction of chemical A the normal population will live and the weaker mutants will not thrive and thefore the mutation dies off.
    If chemical A is introduced the majority of the population will die off leaving only the mutants with all of the resources to thrive and become a wholey resistant population.
    If this continues with more and more chemicals over more and more generations you end up with a super bug (bad).

    Although this is a very small scale example you should get the idea.
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    How do you think evolution happens?
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    (Original post by atheistwithfaith)
    Just a small point, the gene responsible for Sickle Cell Anaemia is recessive, if you have just one copy of the gene you will not develop Sickle Cell Anaemia however you will show resistance to malaria. Having two copies means you will have the disease, which is much worse than malaria.
    Malaria kills far, far more people than SCD.
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    (Original post by Renal)
    Malaria kills far, far more people than SCD.
    Yes it does, I never stated Sickle Cell killed more people but it is a horribly debilitating and incredibly painful disease. Worse for sufferers than Malaria I feel. Also malaria can be treated whereas sickle cell disease cannot.
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    (Original post by atheistwithfaith)
    Yes it does, I never stated Sickle Cell killed more people but it is a horribly debilitating and incredibly painful disease. Worse for sufferers than Malaria I feel. Also malaria can be treated whereas sickle cell disease cannot.
    Sickle Cell can be treated, perhaps not as well as Malaria but there are definitely ameliorating therapies.
 
 
 
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