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    hi, I am sort of confused with the three terms (Evolution, Adaptation, Natural Selection) and their relative associations....
    here are my questions:

    1. How does adaptation occur to cause evolutionary changes?

    Alot of animals become more skilled at carrying out tasks and begin to adapt to it, but then during these adaptations they evolve into better/different animals. For example, an ancestor of duck had a large tail that prevented them travelling on land very well for food, and then over many years they evolve to having shorter tails.
    Why does this occur? Do their alleles suddenly *magically* change as they produce offspring? Because surely as they pass on their genes to their offspring and throughout generations, the genes they pass on will still come from the same source - the duck with the tail. How would it just suddenly disappear?

    2. Natural selection occurs due to advantages in some organisms, but where did these advantages come from in the first place?

    Genes mutations? Chromosome Mutations? Independent Assortment?
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    (Original post by ResidentEvil)
    hi, I am sort of confused with the three terms (Evolution, Adaptation, Natural Selection) and their relative associations....
    here are my questions:

    1. How does adaptation occur to cause evolutionary changes?

    Alot of animals become more skilled at carrying out tasks and begin to adapt to it, but then during these adaptations they evolve into better/different animals. For example, an ancestor of duck had a large tail that prevented them travelling on land very well for food, and then over many years they evolve to having shorter tails.
    Why does this occur? Do their alleles suddenly *magically* change as they produce offspring? Because surely as they pass on their genes to their offspring and throughout generations, the genes they pass on will still come from the same source - the duck with the tail. How would it just suddenly disappear?
    No the alleles don't magically change. What happens is that there will originally have been ducks with short tails and ducks with long tails. Over the years the ducks that were mostly likey to survive were the ducks with shorter tails, so the larger tails will die out (Darwin's survival of the fittest theory). The ones with shorter tails will eventually breed and breed out the alleles for the larger tail, so they have evolved to having shorter tails.
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    (Original post by kieshaxxx)
    No the alleles don't magically change. What happens is that there will originally have been ducks with short tails and ducks with long tails. Over the years the ducks that were mostly likey to survive were the ducks with shorter tails, so the larger tails will die out (Darwin's survival of the fittest theory). The ones with shorter tails will eventually breed and breed out the alleles for the larger tail, so they have evolved to having shorter tails.
    ahh cheers, I think that makes sense now. Survival of the fittest, and the struggle for existence.
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    also, does anyone know how bacteria reproduce?
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    (Original post by ResidentEvil)
    also, does anyone know how bacteria reproduce?
    Asexually, The reproduce with having to have sex with another similar organisim i know that and extremly quickly
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    (Original post by ResidentEvil)
    also, does anyone know how bacteria reproduce?
    Asexual reproduction by BINARY FISSION. Although they don't sexually reproduce they are able to exchange genetic material via horizontal gene transfer - eg exchanging plasmid DNA via their sex pili.
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    adaptation is caused by gene mutations or just basic prescence of genes that allow thre adaptation. adaptation is a result f natural selection....only the fittest survive....and over time this leads to evolution, which is how different species change and evolve
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    (Original post by Tribi18)
    Asexually, The reproduce with having to have sex with another similar organisim i know that and extremly quickly

    where did you hear this????? It is not corret!
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    Suprised you know so much and yet you know so little.. Evolution is the obvious answer as everyone will tell you.................
    (Original post by ResidentEvil)
    hi, I am sort of confused with the three terms (Evolution, Adaptation, Natural Selection) and their relative associations....
    here are my questions:

    1. How does adaptation occur to cause evolutionary changes?

    Alot of animals become more skilled at carrying out tasks and begin to adapt to it, but then during these adaptations they evolve into better/different animals. For example, an ancestor of duck had a large tail that prevented them travelling on land very well for food, and then over many years they evolve to having shorter tails.
    Why does this occur? Do their alleles suddenly *magically* change as they produce offspring? Because surely as they pass on their genes to their offspring and throughout generations, the genes they pass on will still come from the same source - the duck with the tail. How would it just suddenly disappear?

    2. Natural selection occurs due to advantages in some organisms, but where did these advantages come from in the first place?

    Genes mutations? Chromosome Mutations? Independent Assortment?
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    (Original post by mongoose)
    Asexual reproduction by BINARY FISSION. Although they don't sexually reproduce they are able to exchange genetic material via horizontal gene transfer - eg exchanging plasmid DNA via their sex pili.
    This is correct. Bacteria (and all prokaryotes) divide by means of binary fission. The circular DNA molecule is replicated; then the cell splits into two identical cells, each containing an exact copy of the original cell's DNA (with the exception of spontaneous mutations).

    see here: [img]http://www.emc.maricopa.edu/faculty/...nimationC2.gif[img]

    However, as pointed out the sexual transfer of DNA is posible through the passage of the F-factor (or F-Plasmid).

    The two strains involved have to be specific kinds - one F+ and one F-. The F+ one passes the F-plasmid through pili to the F- strain, making the F- strain F+.

    The F-plasmid can be transfered in a 'free' form or with parts of the bacterial chromosome if it has become intergrated. Where the F-plasmid becomes intergrated, it usually becomes interegrated into the recipient genome too by way of recombination using the bits of the F+ chromosome it has aquired during transfer. Integrated strains are known as Hfr strains (high frequency of recombination).
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    (Original post by ResidentEvil)
    also, does anyone know how bacteria reproduce?
    Don't they (on a simple level) reproduce how we grow -- Mitosis.
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    (Original post by ResidentEvil)
    hi, I am sort of confused with the three terms (Evolution, Adaptation, Natural Selection) and their relative associations....
    here are my questions:

    1. How does adaptation occur to cause evolutionary changes?

    Alot of animals become more skilled at carrying out tasks and begin to adapt to it, but then during these adaptations they evolve into better/different animals. For example, an ancestor of duck had a large tail that prevented them travelling on land very well for food, and then over many years they evolve to having shorter tails.
    Why does this occur? Do their alleles suddenly *magically* change as they produce offspring? Because surely as they pass on their genes to their offspring and throughout generations, the genes they pass on will still come from the same source - the duck with the tail. How would it just suddenly disappear?
    There is nothing sudden about evolution. Nothing at all. The changes happen through beneficial natural, genetic mutations in the replication of DNA.

    (Original post by ResidentEvil)
    2. Natural selection occurs due to advantages in some organisms, but where did these advantages come from in the first place?

    Genes mutations? Chromosome Mutations? Independent Assortment?
    Same answer really.
 
 
 
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