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Evolution: Theory or Fact?

  1. Dec 6, 2005 #1
    Wikipedia states that evolution is fact; however, how evolution works is theory. Is this true?

    A friend of mine doesn't believe in evolution, and I have been trying to convince him. Is there a scientific dictionary that will give me an answer?
     
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  3. Dec 6, 2005 #2

    cronxeh

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    Theory is as best and as reliable as a fact gets. When there is evidence to contrary of evolution being false, then it is no longer a theory, but rather a hypothesis.

    No matter what you tell your friends its not going to make sense to him. He should take 2 courses in Biology at college/university level. In the event he has no desire to understand the matter, you in turn should not waste your time trying to persuade such an individual of enormous magnitude of ignorance that the light of day itself can not escape their presence.
     
  4. Dec 6, 2005 #3
    Alright, thanks.
     
  5. Dec 6, 2005 #4
    The part that animals change over time is a fact. We have obviously seen this happen.
     
  6. Dec 6, 2005 #5

    selfAdjoint

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    Evidence for evolution

    See the Evidence for Evolution essay at talk.origins.archive. They can experimentally make bacteria evolve. Many plant species are shown to evolve, with detailed genetic confirmation. And fish in an African lake are in the process of speciating. The point is not that animals can change with time but that species arise due to the changes. And this is a fact, according to the evidence brought forth.

    That the mechanism for this speciation is variation and natural selection is a theory, but this is a theory in the same sense that relativity and quantum mechanics are. The detailed mechanisms are supported by the experiments.

    For what the public calls a theory, scientists use other words, like hypothesis and conjecture.
     
  7. Dec 6, 2005 #6

    Pengwuino

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    If he's like me and can't handle anything that doesn't have a thousand and one formulas related to it, don't bother.
     
  8. Dec 6, 2005 #7
    Thanks again. I am curious because my friend asked me why all species don't evolve. I said I wasn't sure that was true, but, if it was, that doesn't discredit the theory of evolution. Do all species evolve?
     
  9. Dec 6, 2005 #8

    iansmith

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    All species evolve but not all evolution is perceivable in human life spam.

    Species with smaller generation time will appear to evolve quicker. The best example are bacteria vs. human. Human have a 20-30 years generation whereas bacteria have 20-30 minutes generation time. So over 20-30 years a specie of bacteria will accumulate more genetic variation than a human.

    Human population in Europe have evolved in the last 800 years. The last major black plague epidemic was a bit less than 700 years ago. This epidemic cause the a bottleneck, a well characterized mechanism of evolution, in the human population in Europe. A gene called CCR5-delta32 is though to have been selected during that period of time because of the epidemic. (http://www.ncbi.nlm.nih.gov/entrez/...d&dopt=Abstract&list_uids=15715976&query_hl=4)
    However, recent studies may point that the CCR5-delta32 may not have been selected during the middle ages but that it evolve through neutral evolution mechanism (http://www.ncbi.nlm.nih.gov/entrez/...d&dopt=Abstract&list_uids=16248677&query_hl=1)
     
  10. Dec 6, 2005 #9
    If your friend doesn't believe in evolution because he believes in god, i have something to say:

    Some guy (I'll post his name afer I remember it) did some experiment that simulated the conditions of earth 4 billion or something years ago. With the amount of heat and lightning of that time, he saw that amino acids were forming in the soil. One theory of evolution is that organisms evolved from simpler organisms which were made of amino acid that came out of the ground. Now, in the Koran (and I believe this is in the Bible too) it says that man was made of soil, or man came from the earth, something like that. So, these two theories (well, one theory, one holy scripture) pretty much agree.

    Now, I learned of this experiment from a Bio textbok in junior high while studying for the Regents, so I don't have the textbook at my disposal right now, but I will post the missing information as soon as I do.

    If your friend believes in god, this might help.
     
  11. Dec 6, 2005 #10

    iansmith

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    That is not evolution because evolution does not deal with the origin of life. Abiogenesis is one of the theories that deal with the origin of life.
    http://en.wikipedia.org/wiki/Origin_of_life
     
  12. Dec 7, 2005 #11

    adrenaline

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    Your friend is totally hung up on the vernacular meaning of "theory".
    This is what it boils down to.
    The existence of biological evolution is a fact.
    We are less certain of the exact mechanism of evolution so there are many theories about its mechanism.
    In science, theories are structures of ideas that explain and interpret facts.
    Facts don't go away.
    Einstein's theory of gravitation replaced Newton's in this century, but the effects of gravity did not go away.
     
  13. Dec 7, 2005 #12

    Moonbear

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    :smile: I'm so happy to wander into a thread on evolution and see so many people understanding it and explaining it properly. The only thing I would disagree with is the suggestion to not bother. I think you should bother, but I also think you're taking the right approach to make sure your own information is correct first. What you shouldn't do is take it personally if he doesn't accept the explanation. Don't push or argue, just explain patiently.

    Also, to Livingod, as iansmith pointed out, abiogenesis is not part of the theory of evolution. The theory of evolution describes the processes that happen after life was already formed. Sometimes clearing up this misconception alone can open up someone's mind to listening to the science, because it is the origin of life that really bothers them and contradicts their religious beliefs. Science does not provide an answer as to how life originated; it is only conjecture at this time.
     
  14. Dec 8, 2005 #13
    Im saying that the Holy Books support abiogenesis and evolution, thus enabling man to come out of the earth, in a sense.
     
  15. Dec 8, 2005 #14

    SGT

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    As Adrenaline pointed, Newtonian and Einstenian theories of gravitation are only theories. Ask your fundie friend to jump from the 20th floor window, since theories are not to be believed.
     
  16. Dec 8, 2005 #15

    jim mcnamara

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    Ultimately it makes no difference.

    To believe essentially means to accept something as fact without proof.

    Fundamental Christians need to validate their point of view. So they resort to finding a proof of something they believe in - after the fact.
    Politicans do this all the time. It's normal human behavior.

    The reason for validating every statement in the Bible is very simple:

    If the creation of the world, as it exists in Genesis, is a story and is not an absolute fact, it then means that part (or parts) of the Bible are stories, and are not absolute truths. Therefore, it now becomes possible that other parts of the Bible may be taken as something other than incontrovertible fact.

    In other words, you are wasting your time trying to convince him/her otherwise.

    See:
    http://www.cnn.com/2005/EDUCATION/11/08/evolution.debate.ap/index.html for folks who put belief at the top of their agenda.

    See this for people who try to reconcile Christian belief and science:

    http://www.lawrence.com/news/2005/dec/05/god_science_and_kooky_kansans_who_love_them_both/

    If you really weant to try logic: www.pandasthumb.org
     
  17. Dec 8, 2005 #16

    cronxeh

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    Hmm.. this is pathetic
     
  18. Dec 8, 2005 #17

    jim mcnamara

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    (IMO) ----
    the Fundamental Christians want a return to something like Scholasticism -where all secular life revolves around the church.

    Also, they have a disproportionate voice in everday politics because they are expected to tithe - contribute 10% of their income - to the Church.
    Apparently there are about 30 million Evangleical Christians in the US, about 10% of the population. Their presence in the media exceeds
    their true numbers by a vast difference, compared with other kinds of "directed" media.

    This means relatively small congregations to have very large politcal impact. What the congregation tithes is supposed to go for good works, and the folks on the receiving end of the money deem purchasing and supporting Christian broadcasting companies good works.

    Urban areas have a minimum of 2 UHF Christian stations, and there are several Christian networks that are on most cable outlets.
     
  19. Dec 8, 2005 #18
    For those of you wondering (if this helps), my friend is Muslim.
     
  20. Dec 9, 2005 #19

    selfAdjoint

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    As I understand it, the Muslim tradition for the past 500 years or so has been to reject regular rational explanations of how the world works (cosmology as well as evolution) because that limits the power of God to do whatever he wants. Newton rejected this belief, saying that the regularities in nature - planets moving in orbits and so on - ARE what God wants. That every time a stone falls under gravity, that's a specific divine miracle. You could make the same argument about evolution.
     
  21. Dec 9, 2005 #20
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