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  1. #1 Just thought of this question 
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    I have heard that some believe the growth process of a child from fertilization to birth is a mirror of evolution.

    One problem I have with Biological evolution is that while systems, especially interdependent systems, developed how did the organism survive. I was studying the progression of the unborn and the easy conclusion for the baby is that the mother provides protection and food for the offspring until birth. At birth however, the systems have to be self sufficient or death would occure. i.e. heart, lungs, liver, digestion, lyphatic, system, excretory systems, etc all have to be present because without any one of these systems the organism would die. What type of support systems would have to be in place for the life form to survive and has there been any evidence of any of this documented?


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    Its fun making babies! Yeah !!!!!!!!!!!!!!!!


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  4. #3 Re: Just thought of this question 
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    Quote Originally Posted by couldbewrong
    I have heard that some believe the growth process of a child from fertilization to birth is a mirror of evolution.

    One problem I have with Biological evolution is that while systems, especially interdependent systems, developed how did the organism survive. I was studying the progression of the unborn and the easy conclusion for the baby is that the mother provides protection and food for the offspring until birth. At birth however, the systems have to be self sufficient or death would occure. i.e. heart, lungs, liver, digestion, lyphatic, system, excretory systems, etc all have to be present because without any one of these systems the organism would die. What type of support systems would have to be in place for the life form to survive and has there been any evidence of any of this documented?
    ontogeny is a recapitulation of phylogeny. unfortunately you are a bit late with your discovery. The theory is probably already dead for 100 years or so.

    That said, there are some similarities still with different stages of phylogeny, but that is merely because they are very important.

    So don't base arguments on things that are not valid.

    And actually the original theory was used to prove evolution. Not disprove it.
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    Not my discovery and no arguement here. Just a question... I'm curious how an organism in the process of evolving from single cell to multicellular could develop systems(circulatory, respiratory, excretory) when the systems are interdendent, over many generations and the tissue that makes up the partially or not yet functional organs of the system could survive. I phrased the question earlier as such not because i thought it was a valid arguement, but because it was the thought process that led me to this query. so again I ask,"

    In the theory of biological evolution how did systems, especially interdependent systems, develop and how did the organism survive during their development. I was studying the progression of the unborn and the easy conclusion for the baby in development is that the mother provides protection and food for the offspring while the systems develop until birth. At birth however, the systems have to be self sufficient or death would occure. i.e. heart, lungs, liver, digestion, lyphatic, system, excretory systems, etc all have to be present because without any one of these systems the organism would die. What type of support systems would have to be in place for the life form to survive during the gradual evolution of these systems and has there been any doocumented evidence to support an answer to this question ?

    (question edited for clarity)

    PS the theory of recapitulation should probably more accurately be described as a hypothesis.
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    Quote Originally Posted by couldbewrong
    Not my discovery and no arguement here. Just a question... I'm curious how an organism in the process of evolving from single cell to multicellular could develop systems(circulatory, respiratory, excretory) when the systems are interdendent,
    What systems are interdependent?

    There have been many independent solutions for developing a circulatory system, same for respiratory systems.

    Why would it be hard?

    Why are you making a problem out of something that isn't.
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    Quote Originally Posted by couldbewrong
    In the theory of biological evolution how did systems, especially interdependent systems, develop and how did the organism survive during their development.
    If you mentally rephrase the way you think about these systems from 'interdependent' to 'specialised' you will be closer to a more typical evolutionarily-based view.

    There is no 'goal' of evolution, but if there had been it wouldn't be to develop interdependent systems. On the other hand, specialised systems is not unreasonable as a goal, because specialised systems allow resources to be used more effectively. EX: If one or two organs (liver, kidneys) can remove waste for an entire organism, then other organs (skin, heart, etc) don't need to expend any energy towards that particular function.

    Here's something that may (or may not) be a useful exercise. Envision a man starting a new company. He will have to handle everything from inventory to production to marketing to accounting. If the company is profitable, he will be able to 'grow' (hire) and the additional employees can specialise in one or another area. This company might grow and grow, with an entire branch devoted to marketing, or human resources, or what-have-you. At some point, the company's parts become 'interdependent' and the company would suffer if one branch was removed. Yet, you can still trace your way back to the first individual, and realise that the company was functional at every step. You can see how the development of this company occured in an stepwise (evolutionary) fashion.

    What type of support systems would have to be in place for the life form to survive during the gradual evolution of these systems and has there been any doocumented evidence to support an answer to this question ?
    Evidence that organisms have become more 'complex' over time, with the development of specialised parts, is primarily found in the fossil record. The oldest life dates with rocks that are some billions (perhaps 3 billion or thereabouts) years old. This life was unicellular, and life remained exclusively unicellular for millions (a billion perhaps) years. Multicellular life appears in more recent rocks, only 2 billion years old. This early multicellular life was not organismal in nature - it was more along the lines of algae, which can be multicellular but has no true tissue differentiation.

    Organisms (plants and animals) appear in rocks that are younger still.

    Alternatively, if you are not happy considering the fossil record, you could examine extant organisms today, and find a wealth of examples of organisms that display degrees of 'development' at various points along the 'single cell to fully developed organism' spectrum. Insects, for example, have a rudimentary circulatory system, in that they have fluid that bathes their tissues, and something like a very primitive heart. However, mammals could certainly not get by with that sort of circulatory system. Worms have rudimentary nervous systems, but nothing much like a brain - and mammals would be hard pressed to get by without a brain. Mammals happen to appear later in the fossil record than worms.

    Some microorganisms form protective coats (you could think of such a coat as a type of skin) around individual cells or groups of cells, and these coats are transient - beautifully illustrating something like an organ that serves a required purpose for survival, but which is completely dispensable during some stages of growth.

    In fact, many microorganisms grow best in ordered community with other microorganisms, in structures called biofilms. Such structures are layered communities, and the layers can be highly defined and required in a particular order for the biofilm to function as a structure. The biofilm is a composite of hundreds of species, and each species having a role within the film - In a manner of speaking this structure represents a multi-species organism.

    I will not hazard a guess as to your personal philosophies, but I believe that many devout creationists don't think beyond a few plants and animals (worse, usually only mammals) when contemplating life on Earth. Plants and animals are an incredibly minute fraction of life on Earth, and it is no wonder these creationists don't realize the obvious nature of evolution, or the exquisite beauty, and utility, of it.
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    Good post freeradical. I especially like your analogy to the development of a business. Having been self employed, and having worked in small, medium and multinational companies, the example resonated with me.

    Quote Originally Posted by spurious monkey
    ontogeny is a recapitulation of phylogeny. unfortunately you are a bit late with your discovery. The theory is probably already dead for 100 years or so.
    Not quite. It was still popular with palaeontologists in the 1960s. It may not be valid for the fetal developmen t of a human, but it worked quite nicely for ammonite sutures, if I remember correctly. The mistake is taken it as an absolute, rather than as a useful, first approximaion, rule of thumb.
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    Indeed that is a good analogy. I do get the inderdependent vs specialized point as well. (pardon my rudimentary terminology please) For an organism to be an organism wouldn't it need to respirate, consume, and produce waste. From single cells to mammals does all life follow that pattern? If so, how could an organism with a specialized circulatory system be oxegenated enough for the tissues to survive without the presence of a respiratory system of equal importance?. I have never seen a model for that type of species. If you have a circulatory and respiratory system something has to fuel them so digestion is neccesary. If you have digestion, there would need to be a filter to process the good food from the bad stuff (poisons, viruses, parasites, etc.) and seperate or eliminate harmful things taken in with the food. If you have something that processes the food, the "fuel" has to be delivered to the rest of the orgasim as does the oxygen so again a circulatory system, simple or complex, is needed. Other support systems like Lymphatic and such could be considered secondary systems not absolutley neccesary for survival but I know we wouldn't make it to far without our immune system. I understand the concept and the logic behind systemic develpment in earlier organisms, but in practice I don't see how an "unbalanced" organism can survive. If you have to blame something, blame my TRS 80 (yes i'm showing my age). I had one of the first sim games where you had to balance and create a world where the atmosphere is stable and the animal and plantlife control and provide for the survival of the other. Essencially you had to create a biosystem. The longest my world ever survived was 280 (/around there) days. Are there any models that explain system development and maintain the balance mentioned above

    (sorry if I have been unclear in the question, I appreciate your time)
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    Quote Originally Posted by couldbewrong
    I understand the concept and the logic behind systemic develpment in earlier organisms, but in practice I don't see how an "unbalanced" organism can survive.
    they don't.
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    Quote Originally Posted by couldbewrong
    Indeed that is a good analogy. I do get the inderdependent vs specialized point as well. (pardon my rudimentary terminology please) For an organism to be an organism wouldn't it need to respirate, consume, and produce waste. From single cells to mammals does all life follow that pattern? If so, how could an organism with a specialized circulatory system be oxegenated enough for the tissues to survive without the presence of a respiratory system of equal importance?. I have never seen a model for that type of species. If you have a circulatory and respiratory system something has to fuel them so digestion is neccesary. If you have digestion, there would need to be a filter to process the good food from the bad stuff (poisons, viruses, parasites, etc.) and seperate or eliminate harmful things taken in with the food. If you have something that processes the food, the "fuel" has to be delivered to the rest of the orgasim as does the oxygen so again a circulatory system, simple or complex, is needed. Other support systems like Lymphatic and such could be considered secondary systems not absolutley neccesary for survival but I know we wouldn't make it to far without our immune system. I understand the concept and the logic behind systemic develpment in earlier organisms, but in practice I don't see how an "unbalanced" organism can survive. If you have to blame something, blame my TRS 80 (yes i'm showing my age). I had one of the first sim games where you had to balance and create a world where the atmosphere is stable and the animal and plantlife control and provide for the survival of the other. Essencially you had to create a biosystem. The longest my world ever survived was 280 (/around there) days. Are there any models that explain system development and maintain the balance mentioned above

    (sorry if I have been unclear in the question, I appreciate your time)
    I apologize if I misunderstand you, but it seems that you think the different organ systems of animals have evolved independently - as though animals had complex nervous systems before they developed circulatory systems, for example. And that just isn't so. All these systems evolved together, so as one progressed, the others did too. Primitive animals began with very simple versions of these systems, and as they evolved, the systems became more and more complex. But at any one point they still all functioned together. Because, as Spurious pointed out, if they didn't function together, the animal wouldn't survive. Does this help somewhat?
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    Ok so all the systems did form together at the same time. The jump from single cell to multicellular with systems is the first large jump. I don't have any issues with the concept of adaption. (Adaption is where the hypothesis of evolution began when Darwin continued following his uncles ideas and made his scientific observations). Is there a model or explanation of life from single cell to the first organism that is multicellular with basic body systems in place?
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    Quote Originally Posted by couldbewrong
    Ok so all the systems did form together at the same time. The jump from single cell to multicellular with systems is the first large jump.
    Multicellular didn't arrive fully fledged in the modern form. Multi cellular started off with one cell type, gradually increasing in complexity. What was needed for the arrival of conplexity was modularity. The ability to tinker in one module without affecting another one.

    And that's what happened. And I saw it was good.
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    Quote Originally Posted by couldbewrong
    The jump from single cell to multicellular with systems is the first large jump.
    Without wishing to confuse you (and in hopes of doing the reverse) this not so. All the early single celled organisms were prokaryotes. Bacteria are prokaryotes. These are comparatively simple when we set them beside eukaryotes. Eukaryotes, whether single celled or multi-celled, have more complex cell structures. The genetic material resides in a cell nucleus and there are a number of organelles within the cell that carry out specific functions.
    So the the first big leap - once we had any kind of cell at all - was from prokaryotes to eukaryotes. This is now believed to have occured through endosymbiosis, in which a predatory prokaryote absorbed a smaller single cell which then continued to live symbiotically within the larger cell. Chloroplasts, which carry out photosynthesis, and mitochondria, are examples of these. (The idea was first proposed by Lynn Margulis in 1970
    (?).]
    I mention this, because there are many other steps within the development from simple single celled, to complex multi-celled with varied tissues and organs. Nature didn't leap across an apparently unbridgeable ravine. It went downstream and made its way across the cobbles.
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  15. #14 Re: Just thought of this question 
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    Quote Originally Posted by couldbewrong
    I have heard that some believe the growth process of a child from fertilization to birth is a mirror of evolution.

    One problem I have with Biological evolution is that while systems, especially interdependent systems, developed how did the organism survive. I was studying the progression of the unborn and the easy conclusion for the baby is that the mother provides protection and food for the offspring until birth. At birth however, the systems have to be self sufficient or death would occure. i.e. heart, lungs, liver, digestion, lyphatic, system, excretory systems, etc all have to be present because without any one of these systems the organism would die. What type of support systems would have to be in place for the life form to survive and has there been any evidence of any of this documented?

    You mean the womb is a veritable planet of the apes?

    OO ooo OO OO ooo
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    I appreciate your time folks : P My professors weren't knowledgeable enough about evolution to answer these questions so I thank you for your patience. I know this is extreme review for many of you and probably kind of boring. but I do appreciate your help and efforts.

    so did the centrioles evolve into reproductive cells and Endoplasmic reticulum evolve into endocrine and circulatory system, did the golgi apparatus turn into the digestive system? Or did individual organisms turn into tissues of a larger system? If so how did DNA evolve?

    I know I probably should have gotten this in bio 101,102 but I didn't. Again thanks for your help.

    I read up on endosymbionts which suggested that chloroplasts were bacterial endosymbionts. The source I read also spoke of secondary endosymbiosis as an addition to symbiosis to suggest variation.

    IF A is absorbed by B into a symbiotic relationship. and C Absorbs AB in a secondary symbiotic relationship. Then when C divides do A and B also divide? Does the refuting of Lamarckism take anything away from the idea that an "infected" parents daughter cells would have the same symbiots present in many generations in a row which would be neccessary for evolution into a more complex organism. How far off base am I?

    Help.... LOL
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    Quote Originally Posted by couldbewrong
    I appreciate your time folks : P My professors weren't knowledgeable enough about evolution to answer these questions so I thank you for your patience. I know this is extreme review for many of you and probably kind of boring. but I do appreciate your help and efforts.

    so did the centrioles evolve into reproductive cells and Endoplasmic reticulum evolve into endocrine and circulatory system, did the golgi apparatus turn into the digestive system? Or did individual organisms turn into tissues of a larger system? If so how did DNA evolve?
    the endoplasmic reticulum is a subcellular structure made of lipid membrane and accompanying proteins. The circulatory system is made up of many cells. so no, one did not turn into the other. Multicellularity began with multiple cells being able to form beneficial associations with each other, and eventually these associations became complex organizations with different cells specializing for different functions - some became skin cells, some became gut cells, etc.

    IF A is absorbed by B into a symbiotic relationship. and C Absorbs AB in a secondary symbiotic relationship. Then when C divides do A and B also divide? Does the refuting of Lamarckism take anything away from the idea that an "infected" parents daughter cells would have the same symbiots present in many generations in a row which would be neccessary for evolution into a more complex organism. How far off base am I?

    Help.... LOL
    You're on the right track, here. Mitochondria and chloroplast divide and reproduce on their own within the cell, usually according to the cell's needs, so that when the cell splits, half of the organelles go with each daughter cell. This is also why mitochondrial DNA is only passed from a mother to her offspring; sperm is little more than DNA in a swimming box, but an egg is a complete cell with organelles. Any embryo resulting will have copies of its mother's mitochondria.
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    Quote Originally Posted by couldbewrong
    so did the centrioles evolve into reproductive cells and Endoplasmic reticulum evolve into endocrine and circulatory system, did the golgi apparatus turn into the digestive system? Or did individual organisms turn into tissues of a larger system? If so how did DNA evolve?
    Perhaps it might help if you considered large(ish) multicellular organisms like sponges, or perhaps hydras, or some such. In such organisms, the number of different types of cells is smaller than in organisms like humans. In effect, many of them could be said to have two types of cells - inside cells, and outside cells. It is therefore easy to imagine how these might have evolved, being specialised in their own way, from cells that were either or neither to begin with. Now, of course, the inside cells and outside cells are totally interdependent: the insides need the outsides for protection and a controlled flow of current. The outsides need the insides for nutrition.

    In other organisms, then, the insides became perhaps more specialised, giving rise to two further types of cells when previously just the one type may have served (but pressures of competition change formerly happy situations).

    If I'm not making myself clear I apologise, but I wouldn't want you to go away with the idea that the multi-cellular, organ-producing body is created by DNA using an analogy from organelles within individual cells, or using those organelles as blueprints or some such.

    If the shape of the endoplasmic reticulum has a functional advantage - like providing an optimal surface area for reactions/absorption, then this sort of shape is likely to be used in other places as well - but as independent 're-discoveries' of the properties of that shape (like the complex suface of the insides of our small intestines). The two need not be connected by any more than the inherently efficient nature of the shape they form.

    Hope this helps (but upon re-reading, it might just make things more obscure - 'pologies if so)

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    Sunshinewarrior is making a great point (two actually.)

    I second the recommendation to consider 'simple' multicellular life forms like sponges and multicellular algae. Someone suggested volvox, which is a bizarre-looking organism that may expand your notion of what it means to be multicellular, and there are other members of algae that exhibit some of the simple functions of multicellularity (cooperation and specialisation.) The largest algaes (kelp) appear very plantlike, but lack the advanced 'organs' of xylem and phloem, and thus are not true plants. A kelp is a simple multicellular organism.

    Here is a page describing some of these concepts:

    http://www.ncbi.nlm.nih.gov/books/bv...ell.section.61
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    Or as we developmental biologists like to describe it: evolution of diferentiation!

    a similar basic page:
    http://www.ncbi.nlm.nih.gov/books/bv...io.section.203
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    so mutually benificial relationships encouraged single celled organsims to "stick together" then specialization takes over the benefit becomes a neccessity. So at what point does a Plant, who through this process developed complex systems, begin reproducing thru pollinization. How did that occure? What scenario could produce a need for that adaptation? I would think that once a colony could replicate the entire colony and show traits of heredity that would classify it as a "new" organism. I still don't understand how DNA like we see in humans developed being such a neccessity for reproduction. In plant life it seems easier for the community cells idea to be plausable. But for animal life I still have trouble following to the path to what we see today. From mutually beneficial cells to liver heart lungs or circulatory, respiratory, nervous systems etc. How did the first animals that reproduced sexually figure that one out? and how did they reproduce the year before they started "scromping"

    Thanks for those links they really helped me understand alot about that part of the evolutionary process. And thanks again for your time.
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    Dear Couldbewrong

    Thank you for these questions. In order to address them, may I first suggest that we try to attack the problem of ‘essentialism’, as I’m calling it: the notion that there is something ‘essentially’ that constitutes life, or the group of plants, or multi-cellular organisms, or sexual reproduction, and so on.

    The reason for this is that, in evolution, all changes happen through minor changes over generations, not one of which, on its own, would necessarily be considered necessary/sufficient to warrant the dividing line being drawn there.

    For instance many amoebae form colonies, including slug-like aggregations that actually move like a single organism. Is this ‘true’ multi-cellularity? Why would it be helpful, when thinking about mechanisms, to restrict ‘true’ multi-cellularity to those single bodies that have identical genetic material in each cell?

    The point is that, though a forensic mind would like to be able to say – “This generation, Generation [i]n[i/], is the last of pseudonomia priori, and the succeeding generations, its children in Generation n+1, are the start of pseudonomia posteriori – there is no warrant in nature for this. The change from one species to another does not happen over one generation (except in the very speculative cases of hopeful monsters who get there by a single evolutionary leap), but over hundreds and probably thousands. If we compare the starting and ending points of the succession, we find it clear to say that we can distinguish between two species. Anywhere in-between, however, would leave us with a bit of a problem. It is lucky for the palaentologists and cladists that so few fossils and lineages remain, from all the DNA combinations that have existed, or else we would never have modern taxonomy.

    Bearing this in mind, let’s look at your first query:

    so mutually benificial relationships encouraged single celled organsims to "stick together" then specialization takes over the benefit becomes a neccessity. So at what point does a Plant, who through this process developed complex systems, begin reproducing thru pollinization. How did that occure? What scenario could produce a need for that adaptation?
    Pollination is a form of sexual reproduction. Our best understanding of the situation is that sexual reproduction evolved probably only once, amongst the main multi-cellular clade (green plants, fungi and animals), before its lineages diverged. If this is the case, pollination is simply the same as sexual intercourse in humans, with the mechanism adjusted to suit the lifestyle of plants.

    The mechanism of pollination is therefore no different in principle to that of fish spawning, say: the ‘male’ produces large numbers of sperm/pollen, the female a much smaller number of eggs/ova. The sperm/pollen seek the eggs/ova, and not the other way around. This characteristic developed early in the history of sexual reproduction and hasn’t changed since. So plants inherited the pattern, and merely developed various pollination techniques in order to manage it in their way. The variety of methods by which plants do this can be seen by comparing the various clades/groupings: gymnosperms, angiosperms, ferns, mosses and so on.

    Why sexual reproduction developed at all is a completely different question, with fascinating implications, and no definitive answer yet: though George Williams’ (?) notion of parasite avoidance may be said to be the leading hypothesis for now.

    The second part of your query, therefore:

    I would think that once a colony could replicate the entire colony and show traits of heredity that would classify it as a "new" organism. I still don't understand how DNA like we see in humans developed being such a neccessity for reproduction. In plant life it seems easier for the community cells idea to be plausable. But for animal life I still have trouble following to the path to what we see today. From mutually beneficial cells to liver heart lungs or circulatory, respiratory, nervous systems etc. How did the first animals that reproduced sexually figure that one out? and how did they reproduce the year before they started "scromping"
    The sexual reproduction issue I have dealt with above. What about what you call the ‘necessity’ for reproduction.

    Here we come to the heart of the whole evolution/gene-centredness debate. The natural selection argument is simple in this matter: if conditions are available that favour reproduction, and simple structures exist that can reproduce, then eventually the environment will be filled with reproducers – not because they ‘want’ to, but because that’s what they do, without motive. This motiveless behaviour can still be analysed game theoretically, as though lineages/nature were rational agents, and the results are magnificently fecund in their explanatory power.

    The point I am trying to make, however, is that their need be no ‘motivation’ other than this: that the reproducers that dominate the environment will be those that (or who) reproduce, in general, more aggressively than others. Eventually this will result in an environment populated with aggressively reproductive entities. That’s ‘how’ “DNA like we see in humans developed being such a neccessity for reproduction”.

    Hope this helps.

    cheer

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    Doesn't all life reproduce (or die out). I understand the concept of slow changes over many generations. I am still having problems understanding how systems actually developed. Let take another angle.


    Going from Modern man backward (skip the small steps please) what was our direct ancestor that had a 3 chambered heart? or if the 4 chambered heart developed not by stages of 1 chamber then 2, then what good was the tissue before it began to beat and pump blood? What was the heart before it was the heart. If it was a beneficial tissue what was its job? If it was non beneficial tissue how did it develop forward instead of being eliminated as "extra and useless" in subsequent generations.
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    Quote Originally Posted by couldbewrong
    Doesn't all life reproduce (or die out). I understand the concept of slow changes over many generations. I am still having problems understanding how systems actually developed. Let take another angle.


    Going from Modern man backward (skip the small steps please) what was our direct ancestor that had a 3 chambered heart? or if the 4 chambered heart developed not by stages of 1 chamber then 2, then what good was the tissue before it began to beat and pump blood? What was the heart before it was the heart. If it was a beneficial tissue what was its job? If it was non beneficial tissue how did it develop forward instead of being eliminated as "extra and useless" in subsequent generations.
    The first rudimentary heart was basically a portion of blood vessel with more muscle around it than most other blood vessels, to speed movement of blood around the body. So, a 1 chambered heart, you might say. Fish have a 2 chambered heart, amphibians a 3 chambered heart, reptiles a three-but-almost-four chambered heart (there is a short wall dividing the third chamber but blood can still intermix across it), and mammals a four chambered heart. This website:

    http://library.thinkquest.org/C00375..._evolution.htm

    has nice diagrams that show the chambers.

    Remember, every step is still functional. It has to be, or the organism will die.
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    Quote Originally Posted by couldbewrong
    Doesn't all life reproduce (or die out). I understand the concept of slow changes over many generations. I am still having problems understanding how systems actually developed. Let take another angle.


    Going from Modern man backward (skip the small steps please) what was our direct ancestor that had a 3 chambered heart? or if the 4 chambered heart developed not by stages of 1 chamber then 2, then what good was the tissue before it began to beat and pump blood? What was the heart before it was the heart. If it was a beneficial tissue what was its job? If it was non beneficial tissue how did it develop forward instead of being eliminated as "extra and useless" in subsequent generations.
    What paralith said, basically.

    Thought I'd add a general point, though. For a lot of biological scientists, the way to examine, or rather demonstrate, the point that 'intermediate forms' can exist viably on the path to the current state of the lineage, is by examining modern living creatures that can illustrate the ideas in that intermediate form.

    For example, a lot of people have wondered how a structure such as the human eye can have developed. A modern biologist's response lies in demonstrating that intermediate eye stages exist in the world today: there are pinhole eyes, eyespots, eye cups and so on in various other living creatures (you can look it up on the internet!) that shows these are viable options for living creatures.

    Most complex organs (so far we've mentioned just heart and eyes) will have less complex analogues also existing amongst modern animals. The brain is one such, the fish swim bladder another.

    Remember the demonstration that these simpler forms exist amongst living creatures does not show that one particular living lineage descended from the other - just that simpler organs/systems are possible.
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    Quote Originally Posted by couldbewrong
    Going from Modern man backward (skip the small steps please) what was our direct ancestor that had a 3 chambered heart?
    I asked a colleague about this yesterday, as I was hazy on these details.

    I believe that all mammals have four chambered hearts, and I believe that mammals arose once in evolution. I also seem to recall that the predecessor to mammals may have been Pelycosaur (in the early triassic). I don't believe we know how many chambers the Pelycosaur heart had, and I am not certain that they are the direct ancestor of mammals, but I think this has been suggested.

    The ancestor of pelycosaurs, which are sometimes called "mammal-like reptiles," are reptiles. Reptiles have, as Paralith said, a three-almost-four chambered heart.

    These events (rise of pelycosaurs --> rise of first mammals) occured several hundreds of millions of years ago, during period from the Carboniferous to the Triassic.

    I hope that satisfies your request to 'skip the small steps.' :-D You can look earlier in the record and find the predecessor to reptiles which had 2 chambers, and so on.
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    If I'm not mistaken, some reptiles today have variable hearts between 3 and 4 chambers (crocodiles). This suggests that the amount of chambers of an organism's heart might not be the best way to decide if they are in fact predecessors to mammals?
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    Quote Originally Posted by KALSTER
    If I'm not mistaken, some reptiles today have variable hearts between 3 and 4 chambers (crocodiles). This suggests that the amount of chambers of an organism's heart might not be the best way to decide if they are in fact predecessors to mammals?
    Nothing alive today is a predecessor to mammals.
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    What I mean is weather a prehistoric animal had a 3 or 4 chambered heart might not be a good way to judge it a predecessor to mammals? Since modern crocodiles have variable hearts, it might be the same thing going on there. I'm not making claims, just speculating.
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    Interestingly crocodiles also have tooth roots that are like mammals instead of the basic reptile design.

    Maybe crocodiles are not quite what they seem to be.
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    Quote Originally Posted by KALSTER
    What I mean is weather a prehistoric animal had a 3 or 4 chambered heart might not be a good way to judge it a predecessor to mammals? Since modern crocodiles have variable hearts, it might be the same thing going on there. I'm not making claims, just speculating.
    No one piece of evidence is ever used as a deciding in factor in determining phylogenies. We know that an ancient reptile was the precursor to modern mammals based on lots of evidence, and the heart chambers is just one additional supporting piece of data.
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    Thanks folks, researching now
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    Without the use of large amounts of supposition how do scientists reach conclusions about the anatomy of a specimin in the absence of actual tissue. As was pointed out earlier in this post many creature today display variations of systems that are vastly different, strangely similar or seemingly out of place in a given species. What scientific evidence can be gathered relating to the anatomy of a fossil aside from basic muscular and skeletal information? I know occasionally we find an excellent specimin, with organs intact, but from my research that seems to be a vast minority of the time. Doesnt' the variation we see in nature today take away from the credibility of conclusions reached by comparison to modern specimen or fosselized specimen.

    I ask this because as I'm putting together the puzzle pieces I'd like to be sure that I'm basing my evaluations on evidence not supposition.

    Thanks again for all of your time.

    PS Pelycosaur looks cool.
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    For animals, the dental records and general jaw and skull structure are used to hypothesise a basic phylogenetic framework. This is why many of the higher classification names have suffixes such as -dont. Read about one such group here:

    http://en.wikipedia.org/wiki/Eucynodonts

    Other features, such as the number and placement of fenestrae in the skull can also be followed through the fossil record.

    Your skull is more 'developed' than the spicules of a sponge, and can be fossilised much more easily than soft tissues. Using the skeleton as a proxy for evolution is the same logic as using the development of the heart.
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    couldbewrong watch "Alien infection" at 9pm on History channel and look at this http://www.cyber-indian.com/theory/index.html ... you wouldn't get an answer from Darwinists - they are WAY TOO protective when you ask question witch is even a bit different than their views.

    Don't get me wrong I'm not for ID, but they are like "there is no way" kind of guys - somethimes they sound like fanatics (a little bit).

    And that's why we're stuck on the subject since Darwin. Darwin was right as much he could be right with the resources he had for his time - that's how I see him.
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    Quote Originally Posted by cyber_indian
    couldbewrong watch "Alien infection" at 9pm on History channel and look at this http://www.cyber-indian.com/theory/index.html ... you wouldn't get an answer from Darwinists - they are WAY TOO protective when you ask question witch is even a bit different than their views.

    Don't get me wrong I'm not for ID, but they are like "there is no way" kind of guys - somethimes they sound like fanatics (a little bit).
    or, you could try asking us crazy scientists what we think about the theory of panspermia, rather than assuming we'll go bonkers at the mere mention of it. I think it's an interesting theory with merit, but there needs to be a lot more research before we can make a concrete judgement. In the end, though, as was even mentioned on the page you linked to, where viruses evolved doesn't necessarily make the question of how they evolved that much easier.

    EDIT: oops. I got my threads mixed up. I thought this was the viruses thread. Anyhow, in the same sense, how life originated on this planet won't change the facts of how life evolved once it got to this planet, which is what this thread is about. yes, I'm sure. I double checked this time.
    Man can will nothing unless he has first understood that he must count on no one but himself; that he is alone, abandoned on earth in the midst of his infinite responsibilities, without help, with no other aim than the one he sets himself, with no other destiny than the one he forges for himself on this earth.
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    Actually I can explain you pretty much everything with my theory ... and according to it live didn't evolve, but got deployed/annexed - at first look both evolving and deployment look striking similar.

    Viruses got released to annex species, but that release has to get triggered. That can also explain how Mitochondrion and Chloroplast show up. It explains the HERV phenomenon - having hundreds viral DNA debris lodged in our genomes. It explains the need for MHC complex.

    Diseases are needed evil to push humans to learn more about themselves. That's why they get released in waves. But made sure they don't exterminate population.

    And not last the root group is Archaea ... Eukaryotes and Prokaryotes get derived from Archaea.

    And just to answer the question like babies the ecosystem is programmed, but unlike them the ecosystem gets annexed - slowly and in a way that it doesn't exterminate that particular specie. But babies just repeat a process.
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    Quote Originally Posted by cyber_indian
    Actually I can explain you pretty much everything with my theory ... and according to it live didn't evolve, but got deployed/annexed - at first look both evolving and deployment look striking similar.

    Viruses got released to annex species, but that release has to get triggered. That can also explain how Mitochondrion and Chloroplast show up. It explains the HERV phenomenon - having hundreds viral DNA debris lodged in our genomes. It explains the need for MHC complex.

    Diseases are needed evil to push humans to learn more about themselves. That's why they get released in waves. But made sure they don't exterminate population.

    And not last the root group is Archaea ... Eukaryotes and Prokaryotes get derived from Archaea.

    And just to answer the question like babies the ecosystem is programmed, but unlike them the ecosystem gets annexed - slowly and in a way that it doesn't exterminate that particular specie. But babies just repeat a process.
    um, ok. we're all programmed. who programmed us? forgive me, but this sure smacks of ID. perhaps not the kind usually espoused by creationists and the like, but definitely along the lines of "we couldn't have evolved ourselves something had to have designed us."
    Man can will nothing unless he has first understood that he must count on no one but himself; that he is alone, abandoned on earth in the midst of his infinite responsibilities, without help, with no other aim than the one he sets himself, with no other destiny than the one he forges for himself on this earth.
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    There are stuff in this world you could never have no mother what - one of them is the answer of "where it all started" ... that's where parsmenia comes - you concentrate on what is easiest first, meaning how did we get here.

    And who programmed us? We did over and over again.
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    Quote Originally Posted by cyber_indian
    There are stuff in this world you could never have no mother what - one of them is the answer of "where it all started" ... that's where parsmenia comes - you concentrate on what is easiest first, meaning how did we get here.
    others have said that in this forum, and I respectfully disagree. We don't know now. But in the future, we probably will. And it's panspermia, btw.

    And who programmed us? We did over and over again.
    ...we programmed ourselves? You mean, even back when we were all just cells? wow. that's a new one on me.
    Man can will nothing unless he has first understood that he must count on no one but himself; that he is alone, abandoned on earth in the midst of his infinite responsibilities, without help, with no other aim than the one he sets himself, with no other destiny than the one he forges for himself on this earth.
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    And who programmed us?
    Maybe super advanced aliens designed DNA/RNA and seeded the earth in a more direct version of panspermia. Then, strictly speeking, they would be our creators.

    Even though you might say it is complete nonsense, and I would agree, it is much more plausable than the alien being replaced by a god.
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    Quote Originally Posted by KALSTER
    And who programmed us?
    Maybe super advanced aliens designed DNA/RNA and seeded the earth in a more direct version of panspermia. Then, strictly speeking, they would be our creators.

    Even though you might say it is complete nonsense, and I would agree, it is much more plausable than the alien being replaced by a god.
    I'd say it's possible, though there has been little evidence to date in support of such an idea. Even so, if the aliens designed us, where did the aliens come from? At some point, something somewhere had to have evolved naturally, otherwise we wind up with a god again.
    Man can will nothing unless he has first understood that he must count on no one but himself; that he is alone, abandoned on earth in the midst of his infinite responsibilities, without help, with no other aim than the one he sets himself, with no other destiny than the one he forges for himself on this earth.
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    Even so, if the aliens designed us, where did the aliens come from? At some point, something somewhere had to have evolved naturally, otherwise we wind up with a god again.
    Yes, exactly! Whether panspermia happened or not, discussing it conveniently takes the spotlight off of the origin of life. Evidence suggesting panspermia is little and far between at best, with no change in sight. Except if aliens made contact with us and demonstrated how they did it.
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    ...we programmed ourselves? You mean, even back when we were all just cells? wow. that's a new one on me.
    Imagine situation where our sun is ding - what would you do? Would you hope that your existence doesn't stop here? Wouldn’t you try to transplant yourself in some other system? Well even if you do it has to be the whole ecosystem because it cares for you and you can't survive without it. And you have to make sure 110% that it will continue no matter what.

    Maybe super advanced aliens designed DNA/RNA and seeded the earth in a more direct version of panspermia. Then, strictly speeking, they would be our creators.
    BTW you can't create yourself if you already are, so aliens didn't create us. We just got conscious about our situation.

    Even so, if the aliens designed us, where did the aliens come from?
    Aliens you mean us, came from other solar system like ours. They didn’t create us or design us they just designed our recreation here.
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    Quote Originally Posted by KALSTER
    Evidence suggesting panspermia is little and far between at best, with no change in sight.
    The evidence is growing. The opportunity for it too grow further, or for the concept to be falsified, is improving. All we need to do is establish the precise character of dust in interstellar space in general and GMCs in particular.
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    Quote Originally Posted by cyber_indian
    ...we programmed ourselves? You mean, even back when we were all just cells? wow. that's a new one on me.
    Imagine situation where our sun is ding - what would you do? Would you hope that your existence doesn't stop here? Wouldn’t you try to transplant yourself in some other system? Well even if you do it has to be the whole ecosystem because it cares for you and you can't survive without it. And you have to make sure 110% that it will continue no matter what.

    Maybe super advanced aliens designed DNA/RNA and seeded the earth in a more direct version of panspermia. Then, strictly speeking, they would be our creators.
    BTW you can't create yourself if you already are, so aliens didn't create us. We just got conscious about our situation.

    Even so, if the aliens designed us, where did the aliens come from?
    Aliens you mean us, came from other solar system like ours. They didn’t create us or design us they just designed our recreation here.

    Let me get this straight. Your theory is that we humans previously existed on another planet, and that planet was dying, so we decided to recreate another livable ecosystem somewhere else, and do some self modification along the way. If this is correct, (1) how come this isn't recorded in any of our history? where is the evidence of this pan-galactic move? and (2) even if this is the case, then that just means we naturally evolved somewhere else. And life still had to originate naturally somewhere.
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    At first I was verry excited of the "Star dust" too, but now to think of it whatever it was it passed our solar system long time ago.
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    The evidence is growing. The opportunity for it too grow further, or for the concept to be falsified, is improving. All we need to do is establish the precise character of dust in interstellar space in general and GMCs in particular.
    But how would we be able to do that, other than spectroscopic analysis? I know that some complex compounds have been found in interstellar dust, but no protein or anything THAT complex. Or do I have to catch up to some recent discoveries?
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    Firstly, we are employing instrumentation and methodologies for investigating the Universe that were literally undreamt of fifty or sixty years ago. I would expect similar improvements over the next century or two.
    Secondly, spectroscopic examination is one of the routes I think should be productive. We are increasing the 'catalogue' of organic moelcules found in deep space by three or four items each year. I don;t think we currently have instrumentation with the sensitivity to identify low concentrations of complex organics.
    Thirdly, we have had a tentative sampling of cometary materials and interplanetary dust. I think questions marks can revolve around how much interstellar dust we have access to.
    Fourthly, I would not expect the distribution of complex organics (and certainly of any life forms) to be uniform.
    Fifthly, we need interstellar probes to sample distant regions. Granted this means is beyond our current technology and would involve program lengths in millenia, but I don't see any point in thinking small. 8)
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    Good points. Maybe some world government will come to be in a few decades. Then funding should not be a problem anymore and bigger, more ambitious projects can be undertaken.

    Now another thing. Where would the "stuff of life" have originated, if some were found in interstellar dust? Maybe planets with life that exploded somehow, maybe as the result of a supernova? I know stars that go supernova burn out much more quickly that good old Sol, but a few hundred million years might be enough for life to develop? I don't think it could develop inside the dust cloud itself, as the specs would be too far apart for different elements to mix continuously.
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    (Aside from the precursors to life that are found on space rocks, there are other lines of evidence for panspermia. There is (semi) recent evidence that the interior of a meteorite could be well enough protected that life could survive entry through the atmosphere, and some believe that the "martian meteorite" shows evidence of having hosted life, inside. There are counterarguments to such evidence, of course. )
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    I like the idea that prebiotic chemistry is active in GMCs (Giant Molecular Clouds) and may even advance to the point of generating living organisms. My reasons are several:
    a) I am uncomfortable with the comparatively short time frame between the formation of the Earth and the emergence of the first life. It might be possible for life to emerge in a couple of hundred million years, but it seems more plausible, to me, that it would have arrived here from elsewhere.
    b) A proportion of GMCs are hot (the majority are cold, only a few degrees above absolute zero). The combination of heat, massive volumes, vast quantities (and varieties) of organic molecules, and extensive surface areas (dust particles) for these molecules to adhere to, provides an environment that seems to me ideal for permitting the emergence of complex pre-biotic chemistries, up to and including primitive life.
    c) I like off the wall ideas. 8)
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    There is also ongoing auto-catalytic chemical research. Ex: Ribonucleic acids will catalytically self-replicate on certain clays, which is consistent with predictions of non-cellular portions of the origin of life process. This does not relate directly to panspermia. It might suggest that any pan-spermatic event had a molecular window through which it could have rained down to the planet.

    Following this line of thought, one could argue that if the planet relied on certain elements or biological molecule precursors to rain down on the planet, that the point at which this happened (amino acids etcetera vs full blown cells) could be a wide open window.

    Since a clear line between life and non-life is fuzzy to begin with, the question of whether life came from outer space becomes somewhat more moot. Still an important and interesting process to try to understand.
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    Quote Originally Posted by free radical
    There is also ongoing auto-catalytic chemical research. Ex: Ribonucleic acids will catalytically self-replicate on certain clays, which is consistent with predictions of non-cellular portions of the origin of life process. This does not relate directly to panspermia. It might suggest that any pan-spermatic event had a molecular window through which it could have rained down to the planet.

    Following this line of thought, one could argue that if the planet relied on certain elements or biological molecule precursors to rain down on the planet, that the point at which this happened (amino acids etcetera vs full blown cells) could be a wide open window.

    Since a clear line between life and non-life is fuzzy to begin with, the question of whether life came from outer space becomes somewhat more moot. Still an important and interesting process to try to understand.
    Yup. Me too.
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    I classify them as being derived from Archaea, unlike the current classification - Archaea being a death end branch.

    The idea is to have a Archaea that survive space radiation, temperature variations, divide as slow as possible (cell division every 100-200 years) so it needs less energy, as simple as possible feeding - on chemicals and close loop chain, have very strong mechanisms for DNA repair like Archaea has ... this way it can roam trough the whole universe.
    P.S. Columbia's shuttle crash proved that bacteria can survive reentry.

    That same Archaea has to live and feed on a toxic environment (remember black smokers, yellow stone and your own intestines - yep that the Archaea that makes you FART) - so it can lay down NORMAL environment for eukaryotes and prokaryotes. That's called teraforming.

    At the end it would be astonishing engineered plan. That by the way has to be double checked by running thousands of simulations, for every single possible scenario.
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    Archaea are not 'more ancient' than bacteria. The two groups have a common root.

    Archaea live in extreme environments, as do bacteria.

    We named them archaea, and considered them extremophiles, because we learned about them in the context of our prior knowledge of bacteria. If we had described archaea first, it would have been the bacteria that initially looked somewhat odd.

    They are not particularly more extremeophilic than bacteria, nor are they evolutionarily older. As far as DNA repair under challenign conditions, perhaps you mean the bacterium Deinococcus radiodurans?

    http://en.wikipedia.org/wiki/Deinococcus_radiodurans

    The most striking meaningful difference between the two groups is that most human pathogens are bacterial, but no archaea have been identified (with one possible exception) that are pathogenic. This wouldn't pertain to panspermia.
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    How about look it at that way Archaea has the DNA repair mechanisms of eukaryotes and prokaryotes, plus it's own group of DNA repair mechanisms.

    Maybe just maybe, that's why eukaryote has one thing in common with Archaea and prokaryote has totally different thing in common with Archaea.

    I don't say that Archaea is a pathogen, but special set of DNA inserted from a Archaea in eukaryote would make it a eukaryote pathogen.
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  58. #57  
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    Quote Originally Posted by cyber_indian
    I don't say that Archaea is a pathogen, but special set of DNA inserted from a Archaea in eukaryote would make it a eukaryote pathogen.
    this doesn't make sense. could you possibly explain yourself? I had written a post telling you that you were saying total nonsense, but then I realized that I don't even understand the nonsense, so my reply was invalid.

    So please explain. Maybe you said something displaying the application of above normal faculty and I missed it.
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    The most striking meaningful difference between the two groups is that most human pathogens are bacterial, but no archaea have been identified (with one possible exception) that are pathogenic. This wouldn't pertain to panspermia.
    I don't say that Archaea is a pathogen, but special set of DNA inserted from a Archaea in eukaryote would make it a eukaryote pathogen.
    According to my theory Archaea would have the purpose to travel and establish ecosystem. They would deploy simpler cells eukaryotes to do the rest of the job, once the environment is good enough for eukaryotes. Why smaller and simpler, because simple means it will be very faster and more efficient workers. All you do is deploy a blank eukaryote and then by adding genes you could make workers for all kind of tasks. Once the environment is good for the clumsy and more complex prokaryotes - they will be also summon. Anyway back to the point ... that first cell (Archaea) would have the freight of all the blueprint and it'll express it to eukaryotes and that's why
    most human pathogens are bacterial, but no Archaea have been identified (with one possible exception) that are pathogenic.
    Aaaa and also because Archaea is that first extremophile it probably won’t be much space for them in that all green environment.
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    No. No, no, no.

    Your ramblings are so wrong there is no way to point out the sense in which they are wrong. The sentences are not logically constructed, leaving the reader to try to make known facts fit into the premise of whatever it is that you are trying to communicate.

    Garbled, and wrong. This is compounded by your apparent failure to understand what the scientific stance is, as it is explained to you.

    Archaea are not 'the first extremophiles' nor did they terraform Earth. Cyanobacteria arguably 'terraformed' Earth, as Paralith indicated, but only from an anthropogenic point of view (another argument against your posts altogether.) You seem to have read some popular science articles (but only a few) and constructed a fantastical account that in no way fits with hard scientific fact that has been painstakingly researched over the decades.

    Your interest in thinking outside the box is not in itself a bad thing. It is just, in this case, wrong. If it is not wrong, it is certainly poorly presented, in such a manner as to leave me with no other option than to conclude that it is wrong.

    Archaea were not 'the first extremophiles.'
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    Archaea were not 'the first extremophiles.'
    What if the water Cyanobacteria needed first, had to be derived from methane and other toxic sources? All scientists know that planets are all toxic, but they entertain an illusion they'll find one planet with ready to hop-in biosphere. I don't think so.

    According to what you've read. And according to what I think I know it all make sense - and yeah I'm not a very good writer. Sorry if it's that hard to understand me or too much stuff at one time.

    Actually you need knowledge in biology, microbiology, genetics, chemistry, physics, a lot of eco and earth science to get what I mean to say with that theory.
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    cyber_indian, why do you keep turning every thread that is remotely connected to your hobby horse into a clone of your other threads that have been trashed ?
    "Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)
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    Hey nobody stops you from saying what you want. Isn't that why we're here?

    Or is this a close circuit forum. If it is, just say so.
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  64. #63  
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    Quote Originally Posted by cyber_indian
    Archaea were not 'the first extremophiles.'
    What if the water Cyanobacteria needed first, had to be derived from methane and other toxic sources? All scientists know that planets are all toxic, but they entertain an illusion they'll find one planet with ready to hop-in biosphere. I don't think so..
    you are quite limited.

    Oxygen is poison. A biosphere doesn't need oxygen.
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    I don't know who is limited by my question still stands:

    What if the water Cyanobacteria needed first, had to be derived from methane and other toxic sources
    - like all planets we know are.
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    Methane is not a "toxic source." Methane is a carbon source and an energy source. It may have been the earliest carbon and energy source. It may have been required for life to start. You have plenty of methane in your gut. You are not being poisoned by it. Some of your flora live on it.

    You can read about methane based biosystems here:

    http://en.wikipedia.org/wiki/Methanotroph

    What reaction are you envisioning, that would produce water from the oxidation of methane? The reactions that metabolise methane create CO2 and other partially oxidised carbon compounds.

    Oxygen can be an electron acceptor for the oxidation of methane, but it is not required. Other substances, such as sulphate, can provide oxidising potential.

    Current thinking, to my understanding, is that water was deposited on earth from the impact of many icy objects. The first hundreds of thousands of years of the earth's history involved frequent bombardment.

    There are many seeming errors in your assumptions.
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    Methanotroph ... what do you think that ending "-troph" comes from?
    It means thrive on chemicals - non-biomass material. Plus don't you mean Archaea ... lot's of people say bacteria, but they don't know if they mean Eukaryote or Archaea.

    Here is something for you:

    http://www.sciencemag.org/cgi/conten...t/293/5529/484
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  68. #67  
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    Quote Originally Posted by cyber_indian
    Methanotroph ... what do you think that ending "-troph" comes from?
    It means thrive on chemicals - non-biomass material. Plus don't you mean Archaea ... lot's of people say bacteria, but they don't know if they mean Eukaryote or Archaea.

    Here is something for you:

    http://www.sciencemag.org/cgi/conten...t/293/5529/484
    I think you mean "Eubacteria or Archaea" - no bacteria of any kind are eukaryotic. Also, the abstract you linked to only describes bacteria that subsist on methane, of which free radical already said exist, and says nothing of how these species might actually produce water.
    Man can will nothing unless he has first understood that he must count on no one but himself; that he is alone, abandoned on earth in the midst of his infinite responsibilities, without help, with no other aim than the one he sets himself, with no other destiny than the one he forges for himself on this earth.
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    There it is your Darwinist greed ... you think that one single thing will solve all your problems. That would be probably a multi-stage. And there will be others processes for other possible toxic scenarios.

    Have you for instance seen how many stages the Calvin cycle has? Just as an example.
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    as far as i can tell ( and i have only been looking a little bit at the last surge in activity around the topics you have raised) you seem to only be trying to prove your theory by saying its possible and riding on the back of statements and other pieces of information.

    thus far, have you looked at the possibility of trying to disprove your theory?

    perhaps its a mistake for me to post if i haven't read everything that has been said, but you are proposing a theory as an alternative to the theory of evolution or any of the other theory's trying to explain where we came from. you have to expect criticism, and should take them in your stride, rather than lashing out at them.

    science is about disproving, not proving. you must realise that if any few can disprove your theory, or come up with a theory that is much more plausible and correct then it cant be true.

    excuse me if my post is way off.
    Stumble on through life.
    Feel free to correct any false information, which unknown to me, may be included in my posts. (also - let this be a disclaimer)
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    Quote Originally Posted by cyber_indian
    There it is your Darwinist greed ... you think that one single thing will solve all your problems. That would be probably a multi-stage. And there will be others processes for other possible toxic scenarios.

    Have you for instance seen how many stages the Calvin cycle has? Just as an example.
    To repeat:

    Methane is not toxic, except to a subset of aerobes including humans, and only then under certain circumstances (such as inhalation.) Oxygen, on the other hand is toxic to most anaerobes, which comprise a hefty percentage of biomass on the planet.

    Before you begin to talk about the development of human life on the planet, consider the breathtaking diversity of life and the diversity of conditions under which it develops and is maintained. Eliminate ideas like 'toxic' from your argument, as such concepts are much more relative than your usage implies. Eliminate ideas like 'multiple staged processes' as this is a strawman that many here could address were it worth the time.

    Since you have not evidenced comprehension of past points directed at you, and seem unable to construct your theory in a comprehensible way, I suggest that you might benefit from a few more courses in biology and biochemistry.
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    You avoid my answers and the rest that you can't avoid you tell me to abstract myself from. And then you’re saying I'm using straw man tactics ?!?!?!? Not to mention the offences.

    Oxygen, on the other hand is toxic to most anaerobes, which comprise a hefty percentage of biomass on the planet.
    Have you ever thought that maybe that's why Archaea is hard to find?

    Methane is not a "toxic source."
    Try to breed Cyanobacteria in a tank of methane and then well talk.

    the breathtaking diversity of life and the diversity of conditions under which it develops and is maintained.
    I already addressed the "diversity of life" issue, but you chose to ignore it ... about "diversity of conditions" well maybe that's why it's called environment, that's why there is always specie for every one of them. My theory doesn't try to rediscover species, just explain how they got on earth and how they can be retranslated again on other plane in other galaxy in case they have to.

    you seem to only be trying to prove your theory by saying its possible and riding on the back of statements and other pieces of information.
    Trying to prove it not only on a base that it's possible, but also on base that explains every aspect of our evolution and unlike natural selection it doesn’t leave many questions in the gray zone. Also natural selection favor only answers that don’t oppose it even thought they are half way proved.

    P.S. Again I know I’m not the best writer and I apologize for it, but this is also hard to understand because I try to peace different science disciplines together and that’s like thinking multidimensional. Unfortunately that’s the only way to understand my theory. Plus isn’t that the ultimate science – the one that put all science disciplines together.
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    Quote Originally Posted by cyber_indian
    You avoid my answers
    It seems I missed where you provided answers.

    I suggested you read about methanotrophy, in order to understand that methane is not a toxin, but is instead fundamental to origin-of-life (which is fundamental to your theory). You respond by telling me what -trophy means. Some people might take this as an indication that you did not understand my post. You then imply again that methane is toxic. Whilst we humans would not want to breathe loads of it, let us be honest that to call it toxic is a bit misleading in any discussion of origin-of-life.

    Your approach seems to indicate that you aren't interested in learning about the organisms whose history you are attempting to trace.

    and the rest that you can't avoid you tell me to abstract myself from. And then you’re saying I'm using straw man tactics ?!?!?!? Not to mention the offences.
    You've lost me here. I'm happy to discuss origin-of-life but please provide a concrete framework within which we can work, and one that is amenable to observed microbiological fact.

    If you feel your reference to the Calvin cycle is pertinent to this discussion, please outline your argument more fully. The brief counterargument to the suggested complexity of biochemical pathways is (1) biochemical pathways are networks, with many of the intermediates potentially feeding into numerous other pathways and (2) individual reactions within a pathway can provide benefit to the organism regardless of the 'endgoal' of the pathway as a whole.

    Oxygen, on the other hand is toxic to most anaerobes, which comprise a hefty percentage of biomass on the planet.
    Have you ever thought that maybe that's why Archaea is hard to find?
    We do not have trouble finding Archaea. Our lab works with methane-consuming archaea, and we work with them on a daily basis. Archaea are present in your mouth, in your GI tract, in soils, lakes, deserts, etc etc etc. Read any broad environmental microbiological survey and you will find yourself tripping over all manner of archaea (and bacteria) through the inventory that is described.

    Also, you seem to be implying that all Archaea are anaerobic. This would an erroneous assumption. Some archaea are anaerobic, and some are aerobic. Some bacteria are anaerobic, and some are aerobic.

    It is true that the vast majority of microorganisms are difficult to cultivate, but this difficulty spans bacteria as well as archaea, and this has no bearing on your proposal for origins of life in any event.


    the breathtaking diversity of life and the diversity of conditions under which it develops and is maintained.
    I already addressed the "diversity of life" issue, but you chose to ignore it ... about "diversity of conditions" well maybe that's why it's called environment, that's why there is always specie for every one of them. My theory doesn't try to rediscover species, just explain how they got on earth and how they can be retranslated again on other plane in other galaxy in case they have to.
    You've lost me again here, I'm afraid.

    No offense is intended. It is good to think outside the box, but you need to be a bit more careful to not lose sight of the facts when you do so.
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    Methane is not toxic below the lower explosive limit of 5% (50000 ppm). However, when methane is present at high concentrations, it acts as an asphyxiant ... Symptoms of more severe frostbite include a burning sensation and stiffness of the affected area. The skin may become waxy white or yellow. Blistering, tissue death and gangrene may also develop in severe cases.
    But still you're forgetting that humans have skin unlike single cell organisms who are very fragile and that was just one of the examples - thought maybe not the best one as you pointed. Thought isn't methane like benzene has cleaning and disinfecting properties.

    Calvin cycle example is to outline that there isn't anything in nature that is single step process; whether is from chemical or microbiological point of view. And you're not to expect that it'll be that simple.

    I'm not implying that all Archaea is anaerobic; I'm implying that 99.9% of the normal species wouldn't thrive where Archaea would.

    P.S. Have you read this yet, because you sound like you didn't.

    http://www.cyber-indian.com/theory/index.html
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    Quote Originally Posted by cyber_indian
    Methane is not toxic below the lower explosive limit of 5% (50000 ppm). However, when methane is present at high concentrations, it acts as an asphyxiant ... Symptoms of more severe frostbite include a burning sensation and stiffness of the affected area. The skin may become waxy white or yellow. Blistering, tissue death and gangrene may also develop in severe cases.
    But still you're forgetting that humans have skin unlike single cell organisms who are very fragile and that was just one of the examples - thought maybe not the best one as you pointed. Thought isn't methane like benzene has cleaning and disinfecting properties.

    Calvin cycle example is to outline that there isn't anything in nature that is single step process; whether is from chemical or microbiological point of view. And you're not to expect that it'll be that simple.
    I'm happy to respond to any of that if it is important to you.

    I'm not implying that all Archaea is anaerobic; I'm implying that 99.9% of the normal species wouldn't thrive where Archaea would.
    (What is a normal species, please?)

    This quote is the statement that prompts my response here. I believe it to be inaccurate (sorry). Bacteria and Archaea live with one another under most situations. They evolved with one another. Some bacteria live in extreme conditions and are capable of extreme feats (such as Deinooccus radiodurans). Some Archaea do the same. It is misleading to suggest that archaea have capabilities that are wholly unique amongst microorgansims.

    It is perhaps unfortunate that we termed archaea as we did, 30ish years ago, and that we also called them extremophiles. Although it is true that archaea represent halophiles, thermophiles, barophiles, alkaliphiles and acidophiles (as well as plenty of mesophiles, the ones that live under 'normal' conditions by our yardstick, which are actually quite extreme by origin-of-life standards), the same pattern holds for bacteria. Bacteria can be thermophilic, barophilic, halophilic, alkaliphilic, acidiophilic.... And, some fungi can as well (eucaryotes.) Likely some protists as well.


    P.S. Have you read this yet, because you sound like you didn't.

    http://www.cyber-indian.com/theory/index.html
    No, I haven't. I wouldn't have joined in at all, except that I wished to correct an early inaccuracy in the thread.

    Archaea were some of the first extremeophiles discovered, before the advent of molecular screens for environmental surveys. Because they had differences in cell wall structure and lipid structure compared to Bacteria, and because they were found in environments thought to mimic early earth, they were immediately considered something more ancient than bacteria, and the best candidate for representing early life forms.

    This view has fallen to a somewhat less elevated status in current literature, in part because molecular screens (eg PCR) inform us that bacteria thrive in these environments as well. The more we look, the more we find in extreme environments. There are even multicellular animals thriving in some of these extreme environments.

    http://www.accessexcellence.org/WN/S...xtreme797.html

    That link describes a worm that lives on methane hydrates at freezing temperatures.

    Be well,

    FR
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    This quote is the statement that prompts my response here. I believe it to be inaccurate (sorry). Bacteria and Archaea live with one another under most situations. They evolved with one another. Some bacteria live in extreme conditions and are capable of extreme feats (such as Deinooccus radiodurans). Some Archaea do the same. It is misleading to suggest that archaea have capabilities that are wholly unique amongst microorgansims.
    According to my theory Bacteria has been given those capabilities by Archaea, so Bacteria can continue Teraform when the planet start lacking extreme environments.
    Archaea is active only at the first stage when everything is extreme, because they are made only for extreme environment.

    This view has fallen to a somewhat less elevated status in current literature, in part because molecular screens (eg PCR) inform us that bacteria thrive in these environments as well. The more we look, the more we find in extreme environments. There are even multicellular animals thriving in some of these extreme environments.
    http://www.accessexcellence.org/WN/S...xtreme797.html
    Same can apply for the first multi cell organisms. Although you are missing a peace of the puzzle. Those worms have symbiotic relationship with another Archaea. That Archaea prepare the methane food for the worms, the same way Archaea prepares food for us in our GI tracts. The same one that makes us fart.

    P.S. I have to outline that Archaea have the mechanisms to repair mutation that bacteria uses, multi cell organism uses AND it very own one. That proves it is a predecessor of Bacteria and Multi cell organisms.
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    As a matter of fact here is a little preview:

    - Archaeans dine on a variety of substances for energy, including hydrogen gas, carbon dioxide and sulfur. One type of salt-loving archaean uses sunlight to make energy, but not the way plants do it. This archaean has a light-harvesting pigment in the membrane surrounding its cell. This pigment, called bacteriorhodopsin , reacts with light and enables the cell to make ATP, an energy molecule.

    - A recent article in Astrobiology Magazine (May 19, 2004) by Leslie Mullen reports that halobacteria may be the oldest life form on earth. Comparisons of small ribosomal RNA sequences indicate that halophilic bacteria are closely related to the methanogens. Both types of bacteria are now classified in the kingdom Euryarchaeota within the Archaea domain. Halophiles need oxygen while methanogens are anaerobic; however, halophiles can produce energy without oxygen in two ways: from the degradation of arginine, and by using the photosynthetic molecule bacteriorhodopsin). It has been suggested that these two methods of anerobic energy production are the last remnants from the halophile's anaerobic ancestry when the earth's atmosphere lacked free oxygen gas more than 2 billion years ago. Another survival adaptation of extreme halophiles is their exceptional resistance to solar radiation.

    - DiRuggiero's team has learned that when it comes to DNA repair, Halobacterium is something of a "Renaissance bug." It dabbles in a bit of everything. Its genome of only 2,400 genes contains several distinct sets of DNA-repair mechanisms. Some of these sets of tools are like the DNA-repair tools found in plants and animals, other sets are more like those of bacteria, and still others are characteristic of a lesser-known group of life called "Archaea" (the group that Halobacterium belongs to). Halobacterium has them all. Beyond even that, Halobacterium has a few novel DNA-repair mechanisms that no one has ever seen before!

    - Thermococcus gammatolerans - archaeon is nearly as radioresistant as Deinococcus radiodurans, which is capable of withstanding an instantaneous dose of up to 5,000 Gy with no loss of viability, and an instantaneous dose of up to 15,000 Gy with 37% viability. While a dose of 10 Gy is sufficient to kill a human, and a dose of 60 Gy is sufficient to kill all cells in a culture of E. coli.

    - Endoliths can survive by feeding on traces of iron, potassium, or sulfur. As water and nutrients are rather sparse, endoliths have a very slow procreation cycle. Early data suggests that some only engage in cell division once every hundred years. As most endoliths are autotroph, they can generate organic compounds essential for their survival on their own from inorganic matter.

    - Halobacteria can repair badly damaged DNA. "We have completely fragmented their DNA. ...And they can reassemble their entire chromosome and put it back into working order within several hours," says Adrienne Kish, a member of the research group studying Halobacteria at the University of Maryland. These Archaea can also survive extreme dryness, a hard vacuum, and of course, high salt concentrations. We are not the only ones to notice that Halobacteria could use these capabilities to survive in space.

    - The most recent view is that the first cells on earth might have been extreme thermophiles.

    - Archaeal photosynthesis - the earliest photosynthetic organisms lived in an anaerobic atmosphere.



    - Evolution builds on what already exists, in small steps, each one having a selective advantage over preexisting adaptations.

    - Viruses today spread genes among bacteria and humans and other cells, as they always have... We are our viruses - Lynn Margulis.

    - Bacteria trade genes more frantically than a pit full of traders on the floor of the Chicago Mercantile Exchange - Lynn Margulis and Dorion Sagan.


    P.S. Those are all quotes form books, internet, newsletters and magazines.
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