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  1. #101  
    I do beliave that species evolve in the species there is proof to that.
    I believe they are adapting to changes
  2. #102  
    Monday, June 25 12:01 AM EST

    Atheist Still Unconvinced
    After Meeting with God


    By Brian Briggs

    Silverthorne, CO - After a marathon closed door session with God, atheist Herman Morison remains unconvinced of God's existence. God still believes he exists. Both parties agreed to meet until their issues are resolved.

    Read full story...
    “Reality is that which, when you stop believing in it, doesn't go away.” (Philip K. ****)
  3. #103  
    Quote Originally Posted by captaindan View Post
    Chris I would like you to share one example that one species changed to another. That there DNA changed. please
    Definition of species - there are a range of definitions, depending on what type of biologist you ask. The "folk" definition is one used by naturalists, based on visual, observational differences in morphology. However, the more accurate definition involves reproductive population and capacity. In short, this definition defines a species as a group of natural interbreeding individuals that are reproductively isolated (incapable of breeding) with other groups. In this case breeding isn't just producing offspring, but producing viable offspring that themselves are capable of reproduction.

    So the key facet is that they CAN'T interbreed naturally with other groups. There are some questions with that definition (asexually reproducing organisms, for example), but at this point it is pretty much the best defiinition we have.

    Observed instances of speciation:

    I will list 5 examples (3 plant, 2 animal), although there are many more. Some of these are observed in laboratory conditions, some in the field.

    1) Maidenhair Fern (Adiantum pedatum)
    Rabe and Haufler (1992) found a naturally occurring diploid sporophyte of maidenhair fern which produced unreduced (2N) spores. These spores resulted from a failure of the paired chromosomes to dissociate during the first division of meiosis. The spores germinated normally and grew into diploid gametophytes. These did not appear to produce antheridia. Nonetheless, a subsequent generation of tetraploid sporophytes was produced. When grown in the lab, the tetraploid sporophytes appear to be less vigorous than the normal diploid sporophytes. The 4N individuals were found near Baldwin City, Kansas.

    (This plant produced offspring that were capable of reproduction with themselves, but not the previous generation - new species)

    2) Stephanomeira malheurensis
    Gottlieb (1973) documented the speciation of Stephanomeira malheurensis. He found a single small population (< 250 plants) among a much larger population (> 25,000 plants) of S. exigua in Harney Co., Oregon. Both species are diploid and have the same number of chromosomes (N = 8). S. exigua is an obligate outcrosser exhibiting sporophytic self-incompatibility. S. malheurensis exhibits no self-incompatibility and self-pollinates. Though the two species look very similar, Gottlieb was able to document morphological differences in five characters plus chromosomal differences. F1 hybrids between the species produces only 50% of the seeds and 24% of the pollen that conspecific crosses produced. F2 hybrids showed various developmental abnormalities.


    3) Drosophila paulistorum
    Dobzhansky and Pavlovsky (1971) reported a speciation event that occurred in a laboratory culture of Drosophila paulistorum sometime between 1958 and 1963. The culture was descended from a single inseminated female that was captured in the Llanos of Colombia. In 1958 this strain produced fertile hybrids when crossed with conspecifics of different strains from Orinocan. From 1963 onward crosses with Orinocan strains produced only sterile males. Initially no assortative mating or behavioral isolation was seen between the Llanos strain and the Orinocan strains. Later on Dobzhansky produced assortative mating (Dobzhansky 1972).

    4) A Test of the Founder-flush Hypothesis Using Houseflies
    Meffert and Bryant (1991) used houseflies to test whether bottlenecks in populations can cause permanent alterations in courtship behavior that lead to premating isolation. They collected over 100 flies of each sex from a landfill near Alvin, Texas. These were used to initiate an ancestral population. From this ancestral population they established six lines. Two of these lines were started with one pair of flies, two lines were started with four pairs of flies and two lines were started with sixteen pairs of flies. These populations were flushed to about 2,000 flies each. They then went through five bottlenecks followed by flushes. This took 35 generations. Mate choice tests were performed. One case of positive assortative mating was found. One case of negative assortative mating was also found.

    5) Gall Former Fly (Eurosta solidaginis)
    Eurosta solidaginis is a gall forming fly that is associated with goldenrod plants. It has two hosts: over most of its range it lays its eggs in Solidago altissima, but in some areas it uses S. gigantea as its host. Recent electrophoretic work has shown that the genetic distances among flies from different sympatric hosts species are greater than the distances among flies on the same host in different geographic areas (Waring et al. 1990). This same study also found reduced variability in flies on S. gigantea. This suggests that some E. solidaginis have recently shifted hosts to this species. A recent study has compared reproductive behavior of the flies associated with the two hosts (Craig et al. 1993). They found that flies associated with S. gigantea emerge earlier in the season than flies associated with S. altissima. In host choice experiments, each fly strain ovipunctured its own host much more frequently than the other host. Craig et al. (1993) also performed several mating experiments. When no host was present and females mated with males from either strain, if males from only one strain were present. When males of both strains were present, statistically significant positive assortative mating was seen. In the presence of a host, assortative mating was also seen. When both hosts and flies from both populations were present, females waited on the buds of the host that they are normally associated with. The males fly to the host to mate. Like the Rhagoletis case above, this may represent the beginning of a sympatric speciation.


    Chris

    (forgot to cite - the five examples listed above are copied from talkorigins.org)
  4. #104  
    Quote Originally Posted by captaindan View Post
    I do beliave that species evolve in the species there is proof to that.
    I believe they are adapting to changes
    Thats what evolution is in a nutshell then. If you believe species can change into other species over time in response to environmental pressures and competition, you believe in evolution. This change is mediated via random DNA mutations and natural selection of advantageous mutations in a population.

    For the horse for example, it was thought changes in the climate caused an increase in grass lands, and led to animals more adapted to plains living (grass diet, running as a form of escape from predators vs hiding) to thrive and leading to the extinction of their ancestors less well adapted to the new circumstances.

    The next step is to see how this could apply to humans. Suppose their was an environmental change e.g. the ozone layer was depleted for the next 100 000 years, leading to an increase in ultraviolet light reaching the ground. The population with darker skin would be at a reproductive advantage, as they would suffer less cancers and would be more successful at having children and raising them. People who have a mutation in their DNA leading to hyper pigmentation would have the same advantage, and would thrive compared to the rest of their unmutated population. Because they have more and healthier offspring the mutation would spread through the population in only a few 1000 years, and life will go on as normal.

    The above is an example of evolution in humans, but not off speciation. That would likely require larger time frames and stronger environmental pressures, plus usually isolation of the reproductive population.

    Surur
  5. #105  
    I believe they can change within there own species. I think someone called it micro evelution.
  6. #106  
    What your saying about humans adapting the would still be humans. but yes I do believe that animals and all living things do evolve to adapt to changes in the enviroment.
  7. #107  
    Quote Originally Posted by captaindan View Post
    I believe they can change within there own species. I think someone called it micro evelution.
    Why would it not be possible for the common ancestor of horse and zebra to devolop into two different species (horse and zebra)?

    Macroevolution is nothing else than microevolution plus time. If you believe in microevolution, you also believe in macroevolution.
    “Reality is that which, when you stop believing in it, doesn't go away.” (Philip K. ****)
  8. #108  
    Quote Originally Posted by captaindan View Post
    What your saying about humans adapting the would still be humans. but yes I do believe that animals and all living things do evolve to adapt to changes in the enviroment.
    Now suppose we take this thought experiment a bit further. Suppose the ozone condition continues, and there develops a further mutation, leading to scaly skin that is extremely resistant to UV damage. This makes the children of parents with this trait more successful. However they are shunned by the rest of the population due to their scary, reptilian looks. Eventually this becomes enshrined in culture, essentially leading to the reproductive isolation of these scaly people, despite living in the mids of others. There then follows further minor mutations which causes the various classes not to be cross fertile (simple changes in the cell membrane of the ovum can cause this), leading to further reproductive isolation, essentially creating a new specie with different phenotype than the rest of the population.

    This is also how traits which have been present at a low level in a population, and may even have been disadvantageous, can suddenly become a selective advantage due to environmental change. Examples are shortened legs in a forest or lack of horns in a similar environment.

    The above is a thought experiment, but certainly possible. Anything unconvincing about it?

    Surur
    Last edited by surur; 04/25/2007 at 08:42 AM.
  9. #109  
    Quote Originally Posted by cjvitek View Post
    Gravity is just a "theory". The idea of atoms is just a "theory". The concepts of biological cells is just a "theory". According to people who question evolution because it is just a "theory"- they should be questining these theories (and others) as well. Yet people very rarely say those are "just" a theory, or question their truth.

    Why?

    When it evolution, people love to use the common definition of the word "theory" instead of how it is used scientifically. The term "theory" in a scientific context is defined differently, and it is important to make that distinction when discussing the "theory of evolution".

    More later...gotta get my daughter a waffle.

    Chris
    I respectfuly disagree with your point, from the Webster dictionary the following:

    Etymology: Late Latin theoria, from Greek theOria, from theOrein
    1 : the analysis of a set of facts in their relation to one another
    2 : abstract thought : SPECULATION
    3 : the general or abstract principles of a body of fact, a science, or an art <music theory>
    4 a : a belief, policy, or procedure proposed or followed as the basis of action <her method is based on the theory that all children want to learn> b : an ideal or hypothetical set of facts, principles, or circumstances -- often used in the phrase in theory <in theory, we have always advocated freedom for all>
    5 : a plausible or scientifically acceptable general principle or body of principles offered to explain phenomena <the wave theory of light>
    6 a : a hypothesis assumed for the sake of argument or investigation b : an unproved assumption : CONJECTURE c : a body of theorems presenting a concise systematic view of a subject <theory of equations>
    synonym see HYPOTHESIS

    In science a Theory is different from a Law (such as the Law of Gravity), the latter being a proven concept - more common in the fields of mathematics and physics. A theory on the other hand is an accepted scientific explanation of a phenomenon based on empirical observation, as more data about the phenomenon is gathered, the theoretical framework is adjusted to accomodate this new information. As such, a theory should not be held as the absolute thruth (doing so would make it a dogma) but rather the best scientific explanation based on the available facts.

    The current theory of evolution is the most accepted scientific explanation regarding the origin of the species. In my line of work I see evolution at work in a very real way.

    When additional data becomes available that puts forth a better theory (one not involving any magical beings or phenomenon) I am open to consider it on it's merits.
    Have a great one...Doc D.

    Phillips VELO > Palm III > Palm V > Palm 505m > Treo 180 > Treo 300 > Samsung i500 > Treo 700p > HTC 6800 > Treo 800w > Treo Pro > Palm Pre > HTC Evo
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    #110  
    Quote Originally Posted by backbeat View Post
    By teenagers, you mean they were each physiologically old enough to procreate, correct?



    Do you believe that God created others, though the Bible does not mention them? If so, based upon what?
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  11. #111  
    Quote Originally Posted by TreoNewt View Post
    I respectfuly disagree with your point, from the Webster dictionary the following:

    Etymology: Late Latin theoria, from Greek theOria, from theOrein
    1 : the analysis of a set of facts in their relation to one another
    2 : abstract thought : SPECULATION
    3 : the general or abstract principles of a body of fact, a science, or an art <music theory>
    4 a : a belief, policy, or procedure proposed or followed as the basis of action <her method is based on the theory that all children want to learn> b : an ideal or hypothetical set of facts, principles, or circumstances -- often used in the phrase in theory <in theory, we have always advocated freedom for all>
    5 : a plausible or scientifically acceptable general principle or body of principles offered to explain phenomena <the wave theory of light>
    6 a : a hypothesis assumed for the sake of argument or investigation b : an unproved assumption : CONJECTURE c : a body of theorems presenting a concise systematic view of a subject <theory of equations>
    synonym see HYPOTHESIS

    In science a Theory is different from a Law (such as the Law of Gravity), the latter being a proven concept - more common in the fields of mathematics and physics. A theory on the other hand is an accepted scientific explanation of a phenomenon based on empirical observation, as more data about the phenomenon is gathered, the theoretical framework is adjusted to accomodate this new information. As such, a theory should not be held as the absolute thruth (doing so would make it a dogma) but rather the best scientific explanation based on the available facts.
    First off, my mistake - gravity is a law, you are correct. That's what I get for typing while my daughter is asking for a waffle.

    A scientific law is as you describe - generally mathematical in nature (or dealing with physics) describing a very specific circumstances/actions/reaction.

    But I would say a theory is considered more certain that you describe it. A theory is based on a hypothesis that has been examined, tested, and has repeatedly been found to be true. Once a scientific hypothesis is accepted as true, it is "elevated" to theory status. There isn't anything "more" true than a theory, there isn't anything a theory can become if it is "proven". As such, a theory is generally accepted.

    I do agree with your statement that theories are adjusted and can be modified as new facts come to light - that is how science works. I didn't mean to imply that it should be held as an absolute truth, or that it is absolutely correct - I was merely pointing out that the claim that something is "only" a theory is misleading, since there really isn't anything MORE than a theory in science. Usually when people make the claim that evolution is just a theory, they are using the term more like hypothesis that theory.

    The current theory of evolution is the most accepted scientific explanation regarding the origin of the species. In my line of work I see evolution at work in a very real way.
    Me too - I am a biologist.

    Chris
  12. #112  
    I think that both sides miss the point. The Bible/Quran/whatever's purpose is to help mankind understand its place on earth and to guide us through life's trials and tribulations. As a scientific/historical document the Bible leaves something to be desired but as a guide to life it's pretty good. On the other hand if all we are is a collection of chemicals that happened to align themselves then what is our purpose? Logically one leads to the other.
    Palm I >Palm IIIi>Palm 505> Zire 71>PEG37>T|X>TREO 700P That's a lot of palming!!
  13. #113  
    Quote Originally Posted by maninrochester View Post
    I think that both sides miss the point. The Bible/Quran/whatever's purpose is to help mankind understand its place on earth and to guide us through life's trials and tribulations. As a scientific/historical document the Bible leaves something to be desired but as a guide to life it's pretty good. On the other hand if all we are is a collection of chemicals that happened to align themselves then what is our purpose? Logically one leads to the other.
    That basically means you are unwilling to believe something which clashes with your religious beliefs, despite how logical the arguments are, or what the evidence is for it.

    What most people are able to do is hold both apposing ideas in their head, and separate the domains. They accept science and its conclusions on a practical level, but use their religious beliefs for moral guidance. Instead of attacking scientific conclusions they consciously avoid examining religious claims too closely, as that would be pointless, and would not help guide them morally.

    Its nearly impossible to reconcile science and literal religion, but fortunately humans are pretty good at keeping separate domains separate in a pretty pragmatic manner.

    Surur
  14. #114  
    Quote Originally Posted by surur View Post
    Athiesm is not a belief system, its the rejection of a belief system.
    .
    .
    .
    Atheism should be the default base state, not some alternate belief system.
    I agree with your statement, as an abstraction is true; atheism is a default base state.

    In reality however, atheism is "practiced" as a core set of (dis)believes and any challenge of those usually triggers a strong emotional response resambling that of theists. In most exchanges that I have witnessed and/or participated, the opposing sides rarely consider any of the arguments made by the other. Sometimes name-calling becomes a tactic when arguments are insuficient to defend a given position.

    If God appeared regularly and did supernatural things I would believe.
    Most atheists wouldn't (myself included), they would try to dismiss the "supernatural" events with science and logic, if unsuccessful, a number of those would simply ignore the events and refuse to believe.
    Have a great one...Doc D.

    Phillips VELO > Palm III > Palm V > Palm 505m > Treo 180 > Treo 300 > Samsung i500 > Treo 700p > HTC 6800 > Treo 800w > Treo Pro > Palm Pre > HTC Evo
  15. #115  
    Quote Originally Posted by maninrochester View Post
    I think that both sides miss the point. The Bible/Quran/whatever's purpose is to help mankind understand its place on earth and to guide us through life's trials and tribulations. As a scientific/historical document the Bible leaves something to be desired but as a guide to life it's pretty good. On the other hand if all we are is a collection of chemicals that happened to align themselves then what is our purpose? Logically one leads to the other.
    I like your line of thinking. I was raised Catholic but find myself agnostic at best these days. That said, I find the Bible to be a valuable book of stories that can help guide one through life. But they are stories that are loosely based on a smattering of facts - likely twisted and contorted as the church evolved. So my attitude toward religion in general is - if it works for you, great. If not, great.
  16. #116  
    Quote Originally Posted by cjvitek View Post
    First off, my mistake - gravity is a law, you are correct. That's what I get for typing while my daughter is asking for a waffle.

    A scientific law is as you describe - generally mathematical in nature (or dealing with physics) describing a very specific circumstances/actions/reaction.

    But I would say a theory is considered more certain that you describe it. A theory is based on a hypothesis that has been examined, tested, and has repeatedly been found to be true. Once a scientific hypothesis is accepted as true, it is "elevated" to theory status. There isn't anything "more" true than a theory, there isn't anything a theory can become if it is "proven". As such, a theory is generally accepted.

    I do agree with your statement that theories are adjusted and can be modified as new facts come to light - that is how science works. I didn't mean to imply that it should be held as an absolute truth, or that it is absolutely correct - I was merely pointing out that the claim that something is "only" a theory is misleading, since there really isn't anything MORE than a theory in science. Usually when people make the claim that evolution is just a theory, they are using the term more like hypothesis that theory.



    Me too - I am a biologist.

    Chris
    And with that I am in complete agreement...
    Have a great one...Doc D.

    Phillips VELO > Palm III > Palm V > Palm 505m > Treo 180 > Treo 300 > Samsung i500 > Treo 700p > HTC 6800 > Treo 800w > Treo Pro > Palm Pre > HTC Evo
  17. #117  
    I think the bible is an amazing book. What other book can you give that was written by what 15 different people, 4 different languages, over a 200 year span and the book has no contradictions.
    War & Piece has contradictions all through out it. That was written by one person.
    Sorry I am not that great of a speller
  18. #118  
    I think even if you are religous you should still have an open mind. I love the LORD and I Love my church that does not mean that all you are wrong. Like I said before who am I to judge anyone. I am FAR from being even close to perfect.
  19. #119  
    Quote Originally Posted by TreoNewt View Post
    Most atheists wouldn't (myself included), they would try to dismiss the "supernatural" events with science and logic, if unsuccessful, a number of those would simply ignore the events and refuse to believe.
    So if angels appeared on every street corner, and you could ask them to perform supernatural miracles for you e.g. miraculously replace a house that burnt down, and they said they worked for the person who created the universe, and this person performed greater miracles occasionally e.g reversing the rotation of earth or separating the sea between New York and Ireland, you would not be tempted to believe?

    In the end science is just another way of understanding the world, and if our system of belief does not explain the majority of phenomena it should be discarded for a system that works better and explains a larger segment of observed phenomena.

    Surur
  20. #120  
    Quote Originally Posted by captaindan View Post
    I think the bible is an amazing book. What other book can you give that was written by what 15 different people, 4 different languages, over a 200 year span and the book has no contradictions.
    War & Piece has contradictions all through out it. That was written by one person.
    Those are fighting words. I thought the Bible was littered with contradictions.

    Surur

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