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lucaspa

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  1. The extracellular matrix is partly the mineral hydroxyapetite, which is in a crystalline form. That's about 60% of the dry weight of the extracellular matrix. However, the organic part of the matrix is composed of proteins, 90% of which is type I collagen. It is not in "crystals". And, of course, there are no crystals within the osteoblasts and osteocytes (the cells) in bone. I have a problem with that. Darwinian evolution requires that more individuals are produced each generation than the environment can support. What if the reproductive rate is so slow that this requirement is not met? I like the "self-sustained chemical system" but I feel that this is too limiting. What about possible life that is energy? No, I'll stick with the 4 criteria: 1. Metabolism 2. Response to stimuli 3. Growth 4. Reproduction
  2. I agree. Military action is only part of the solution. The reason "radical Islam" hates the US and West is that it is indeed losing the battle of ideas. It can't compete peacefully in the marketplace of ideas, so it has to resort to violence to preserve those ideas. That's where the parallels with Nazism come in; those are tactics any and every totalitarian state uses to promulgate its ideas. Our economy, secular society and the freedoms and personal opportunities that come from that are eventually going to take people away from radical Islam. In fact, they already have for the vast majority of Muslims. The way we can lose the conflict is to over rely on the military option and convert neutrals to enemies by using force against people who are just trying to get by. In that regard, we are losing. Where once we only had a radical Islamics in control of Afghanistan, we have managed by our blundering to have radical Islamics undermining Iraq, Afghanistan, and now Pakistan. How much reform did 9/11 cause in the USA? How much "reform" did Islam taking Jerusalem cause within Christianity? There is not going to be any refrom inside Islam if we bomb Mecca! Instead, there is going to be instant hatred of the USA, hatred that the radical Islamists will use to unite all Muslims against us! In Muslims outnumber us considerably and, together, the nations with a majority of Muslims in the population have greater industrial power and more natural resources than we do. The end result of bombing Mecca is a world war with us vs all the Muslim nations and Europe sensibly being neutral and sitting it out. And the result of the war is that the Muslim nations conqueor the USA. The reform in Christianity ONLY came when there was no external enemy. As long as Christianity was engaged in fighting the Crusades, there was no reform. The Catholic Church had a stranglehold on Christianity. It was only after Europe turned inward and were not fighting another ideology were Luther and Calvin able to instigate the Reformation. Of course, that was an extremely bloody affair. Do you really think that such a series of wars today would be just within Islam? No, we have to help Muslims to a better way for their religion to mature. Bombing Mecca won't achieve any of your aims. Good grief! Doesn't anyone read history anymore? No, of course not. Ordinary logic has gone by the boards. Bombing Mecca is not logically tenable as a solution to the current problem. With logic gone, why read history? After all, history is used to logically predict the outcome of actions.
  3. Wait a minute! There is no evidence that Obama believes the political claims of Rev. Wright. Sitting in a pew listening to a sermon and being friends with the man doesn't mean acquiescence in all the ideas. Darwin and the pastor of the Down church had a close friendship that spanned 30 years. The two disagreed on just about everything, yet still had a strong friendship. Should you start doubting Darwin's integrity because of this friendship? Bush has been friends with some of the ministers that uttered a radical comments about 9/11 -- that it was God's punishment for moral decay and acceptance of gays, for example -- but no one thought Bush believed that. What I don't see anyone doing is looking at how the situation appears from Wright's congregation: poor and discriminated against because of their ethnicity. Wright: ""The government gives them the drugs, builds bigger prisons, passes a three-strike law and then wants us to sing 'God Bless America.' No, no, no, God damn America, that's in the Bible for killing innocent people," he said in a 2003 sermon. "God damn America for treating our citizens as less than human. God damn America for as long as she acts like she is God and she is supreme." " Walk in the other man's moccasins for a while. Most drug use is among blacks, most of the main dealers are white. The sentence for use of crack cocaine (used mainly by blacks) is muchharsher than the sentence for cocaine (used mainly by blacks). I can see how Wright reached the conclusion that the government was using the law and prisons as a means to oppress African-Americans. I don't agree that this was the intention, but I'm willing to consider that it may have been the intention of a few, and I'm certainly willing to entertain the idea that oppression was an unintended consequence. And I would not expect people who feel oppressed -- even if they are objectively wrong -- to support the people they feel are the oppressors. Of course they are going to say "God damn America". Shoot, lots of nice white college kids said the same thing in the 1960s due to the Vietnam War. Wright: ""We bombed Hiroshima, we bombed Nagasaki, and we nuked far more than the thousands in New York and the Pentagon, and we never batted an eye," Rev. Wright said in a sermon on Sept. 16, 2001. "We have supported state terrorism against the Palestinians and black South Africans, and now we are indignant because the stuff we have done overseas is now brought right back to our own front yards. America's chickens are coming home to roost," he told his congregation. " He's correct that we terror bombed in WWII. That was policy. He's also correct that we supported state terrorism against the Palestinians and black South Africans. You think that might have made those people angry at us? Yes, we like to see ourselves as pure and innocent, but the fact is that our government has done some pretty nasty things overseas. Sometimes justified by preventing a greater evil, sometimes not. Of course we are not going to like when people try to kill us and we do have a right to defend ourselves. I read Wright's statement that part of that defense is going to have to actually be the good guys we like to think we are. We can't do shit to other people and expect them to just take it because we are the USA and, by definition, we are the "good" guys. I think Obama's speech on race was very good. It was actually an adult talking to adults. It was nice to be treated as an adult by a politician. The views of Wright, mistaken as some of us think they are, need to be listened to. Then we need to put ourselves in those shoes to figure out how we convince Wright and those like him that things are not the way they think. Part of that is reason, but part is changing policy and the particular actions that led to Wright thinking the way he does. A blanket condemnation of Wright is not critical thinking. We are supposed to take claims separately. Yes, some of what Wright says is mistaken. But some isn't. I just finished a book called The Bomber War. It takes an overall look at bomber operations in Europe. Americans talked about "precision bombing" and felt morally superior. But, in fact, they engaged in area bombing just like the British and used much of the same techniques the British did. This was due to cloud cover and the inability to use the Norden bombsight. About 70% of American raids were "blind bombing" = the area bombing. So entire cities were area bombed by the Americans. This was done because any tactic that brought the war to an end was justifiable. I, quite frankly, agree with the logic. However, that gives me a problem in looking at Al Queda. Once Bin Laden declares war on the USA, then his tactics of attacking civilians in NYC and military personnel in Washington by the means available become justified by the same logic as that used to justify night area bombing of Germany. My disagreement with Bin Laden is that I don't think his declaration of war was justified. I disagree with his logic to go to war, and therefore I think it a just war to resist Al Queda. But is the tactic we call "terrorism" what is "evil"? If you insist it is, then we Americans have been just as evil, or worse.
  4. Except on the skin, "dead" cells don't last long. They are dissassembled. We don't have any crystals in us. And the reason they didn't say "crystals" is because that would be wrong. Yes, proteins do interact to form larger structures. Hemoglobin, remember, is 4 proteins and the heme molecule, not a single protein. But these are NOT crystals. Saying they are is stating an error. Sometimes an analogy doesn't help but makes things worse. That's the case here. Was there any doubt? Yes, at the cellular or organismal level we are a set of chemical reactions. That's what "biochemistry" is: figuring out the chemistry of living things. Notice I said "cellular or organismal level". A philosophical question that arises because of our ability to reason and manipulate abstract thought at the level we do is: are we only biochemical machines? This is analogous to the question addressed by Star Trek: was Data "only" a machine?
  5. It's easy. Remember that to be alive the entity has to have all 4 of the following characteristics: 1. Metabolism (both anabolism and catabolism) 2. Growth 3. Response to stimuli 4. Reproduction. It's very easy to see that a dead bacterium has no metabolism. For multicellular organisms, the old saying "poke it with a stick" is testing #3. If there is no response to stimuli and no metabolism, the entity is not alive, even tho it might once have been. Proteins do not exist as "crystals". Proteins can sometimes be "crystallized" in order to do x-ray diffraction. But the reason so many proteins have NOT been analyzed by x-ray diffraction is that they cannot be crystallized. Called "anabolism". However, it's not enough to "drive unfavorable chemical reactions". For anabolism you need to use the energy to make the molecules of the living organism. Yes, those reactions are "unfavorable", but they are very specific unfavorable reactions. If you have a multicelled organism, there is no "two consecutive moments" between life and death. There is a continuum. For instance, an organism can be brain dead, not breathing, and no heartbeat, but most of the cells will be alive. That's how we do cell harvest. In microorganisms, the causes of death have been studied in some cases. In most cases, it's when metabolism ceases. That can have a number of causes. 1. With treatment with penicillin, the cell wall breaks and the contents of the bacteria leak out. The cellular components become separated and metabolism ceases. 2. If we treat bacteria with ethanol or disinfectant, then the proteins are denatured and precipitated. Metabolism ceases. 3. In the case of accumulating oxidative damage, first the DNA stops coding for functional proteins, then the proteins and lipids that are oxidized stop functioning. Metabolism ceases. See a pattern here?
  6. iNow stated the argument very well. Below is what I wrote before I read iNow's response. But "origin of life" does not say "origin of life on earth". As you say, Panspermia "says that life in earth was transfered from some extraterrestrial source and the other stuff that says the link." What's the origin of life at the extraterrestrial source? See? We really don't have an origin of life in Panspermia. Panspermia just pushes the question off earth to some other location.
  7. We still have that communication problem. You are placing the effect on natural selection on reproduction. Instead, natural selection increases the ability of the individual to do better in competition for scarce resources. A consequence of doing better in the competition is that the indivuals will have relatively more offspring than other individuals. I keep hearing you say that natural selection has a direct effect on reproduction. And let's talk "variation", since mutations are only one form of variation. Recombination in sexually reproducing organisms introduces a lot more variation than mutation does. If a variation is neutral in the competition, then we will not see a difference in the frequency of that variation in the population. Well, not quite true, since genetic drift will also alter frequency over a very long time. But for our purposes, "neutral" variations will not change the frequency of the variation in the population. And this is where I question the simulation. It goes against quite a bit of mathematics and observation. That's why I suspect GIGO for the reasons I stated. I add another one: you seem to have skewed your simulation only to look at "reproduction". Now, an issue we are going to have is how emotionally attached you are to your simulation. Are you truly interested in it accurately mimicking evolution or are you going to defend your simulation as "right" and instead label evolution as "wrong"? IOW, are you really interested in seriously considering criticisms of the simulation based upon other data in evolution or are you only interested in using your simulation to challenge evolution? If the latter, then our discussion goes nowhere. Then your simulation is not mimicking natural selection correctly. What you call "random statistical variation" are instead individuals with advantages to reproduction that are better than the mutation (let's call it A). When we get to statistics we are talking about populations. This is what evolution deals with. It selects among the individuals of the population. In the example above, natural selection is operating. It is selecting the variation (call it B) that gives the best advantage to reproduction. Apparently your population has variation that are already B because you introduced them initially. Therefore, if you introduce A, it is not going to replace B because B is already better than A. What you have to do is find a variation C that is better than B. Back to what we are talking about before. Yes, if you have a variation with s = 0.001 but there is already in the population a variation with s = 0.01, then of course the variation with the lower s is not going to succeed. It can't compete with a better variation. However, what do you mean by "random environmental conditions"? Are you referring to something outside the genome? If so, what? What you overlooked was the competition part of natural selection. Natural selection has the variations (individuals) competing against each other. Part of your GIGO was introducingt an "advantageous mutation" that was not as good as a variation already in the population. Of course it did not do well. What you are looking for is a variation better than any variation already in the population. Do that in your simulation. Pick a "mutation" that is only 0.1% better than the best variation in your "statistical variation" and see what happens over the course of many generations.
  8. Jerry, have you gone to PubMed and done a search using the terms "protein, evolution"? I did. There are over 74,000 references. The first one is: Dowling DP, Costanzo LD, Gennadios HA, Christianson DW. Evolution of the arginase fold and functional diversity. Cell Mol Life Sci. 2008 Mar 24; At the end of the post I have a couple of papers for you to start. I even have a book on my shelf called Protein Evolution. There are several books on the subject. Go here: http://www.amazon.com/s/ref=nb_ss_b/105-5714668-1097220?url=search-alias%3Dstripbooks&field-keywords=Protein+Evolution&x=10&y=14 This is different. Now you don't want evolution of proteins That's because proteins arise by chemistry. If you heat amino acids -- either dry as in a tidal pool or at hydrothermal vents, they form proteins. There is quite an extensive literature on this. Most of the work was done prior to 1980. Start here: http://www.siu.edu/~protocell/ http://www.theharbinger.org/articles/rel_sci/fox.html and I can give you further references if you want. Here is the reference list: 1. E Wilson-Miles and DR Davies, On the ancestry of barrels. Science 289: 1490. Sept. 1, 2000. "the structure arose from the duplication and fusion of the gene of acommon half-barrel ancestor" 2. M Buck and MK Rosen, Flipping a switch. Science 291: 2329-2330, March 23, 2001. Describes studies on the motion of proteins that are signalling molecules, including mutations that give activity in the absence of phosphorylation. (also refutes Behe because demonstrates one way to build an IC system). 3. http://compbiol.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pcbi.0030139 Formation of gene families and protein folding 4. Science paper by Doolittle (back in 1981) http://www.sciencemag.org/cgi/reprint/214/4517/149.pdf 8. http://www.sciencemag.org/cgi/content/full/312/5770/97 JT. Bridgham, SM Carroll, J W Thornton Evolution of Hormone-Receptor Complexity by Molecular Exploitation Science 7 April 2006: Vol. 312. no. 5770, pp. 97 - 101 PDF file and other papers here: http://www.uoregon.edu/~joet/pubs.htm
  9. Native Americans -- being H. sapiens -- are descended from H. erectus. But H. erectus in Africa, not Asia. Unless you hold to the AMNH viewpoint that H. ergastor is a separate species (most paleontologists put the H. ergastor specimens in H. erectus) and H. erectus is the Asian descendent species of H ergastor. H. sapiens is the African descendent and N. neandertals would be the European descendent. No one has mentioned that the people who did the first Bigfoot "sightings" have admitted to making up the evidence. Bigfoot, from the confession of the people involved, is a fraud. It's also against everything we know about evolution of other species. No other species has evolved that way that I can find. Of course, then there is the refuting evidence of both the genetics and the fossil evidence.
  10. I think we're having a communication problem. Remember, it's differential reproduction. And it's not "evolutionary selection", but natural selection. Our conversation will go better if we use the terms used by evolutionary biologists. It seems like you are trying to use "replication" as "differential reproduction" but replication doesn't mean that in biology. In your post you talked about "augmenting replication" and "robustness of replication". To any biologist, this means that the individual produces more offspring; that the number of offspring increases. This is different from differential reproduction. A variation can hold replication (number of offspring per individual) either the same or even lower it, as long as more of those offspring survive to reproduce. For instance, look at the number of offspring of salmon and humans. Salmon lay thousands of eggs. They have a replication rate much higher than humans, who have -- at maximum -- 12 -15 kids per woman. Yet what matters is the number that survive and have their own kids. For salmon, this rate is very low. Thus, any variation in salmon that lowers the mortality between egg and reproduction will increase differential reproduction. The individual could lay many LESS eggs (lower replication) and still increase differential reproduction. So, are we on the same page now? Good, but can you see how you threw me off with phrases like "Nature tests replicative success when a species either succeeds and thrives or fails to thrive."? Species are not individuals. Species are populations of individuals. OK, here is the problem. What are those "random variations in replication" going to do? IOW, what do we mean by "random"? Random here = effect on differential reproduction. So, in your system any "random" variation that increases the number of offspring per unit time is going to be selected for. Even if that variation increases the replication rate even 1% Keep reading, because there is another problem with how you are using the numbers: For example. If a given mutation effects replication advantageously such that any organism with that mutation replicates 1% more often than the average for that organism, but the average replication rate for that organism is 10% per month, and random environmental activity kills 9% per month, Replication rate is not going to be in percentages. It is going to be in number offspring per unit time per individual. So, you can have a mean replication rate of 100 offspring per month per individual. A 1% increase of THAT is going to mean 101 offspring per month per individual. Now, "random environmental activity kills 9% per month" doesn't make sense, either. Instead, you can say that 90% of the individuals per generation die. That is the meaningful number. So: Individual A has 100 offspring per month (the mean) and 90% of them die. That leaves 10 individuals left. Individual B has 101 offspring per month and 90% of them die. That leaves 11 individuals left. So then we start again with the next generation: Generation 2: All A individuals have 1000 offspring total, of which 100 survive. All B individuals have 1100 offspring total, of which 110 survive. You can see that generation 2 has a net increase of 9 individuals over generation 1. And it will continue. Now, this is your setup. In it, the number of individuals per generation can increase. In the real world the total number of individuals of both A and B would be fixed. Instead of actual numbers, we would be looking at the frequency, or proportion of individuals with the trait. So let's do some of those numbers: Total population = 1,000 Fitness = 1.01 (a 1% increase in fitness). s = 1 - fitness. It is general to use "p" and "q" for frequency. p + q = 1. Frequency of q = 0.999 (999 individuals out of 1,000 have the original variation = A) Frequency of p = 0.001 (a new mutation appears in 1 individual = B) The equation is: delta p = (1/2)spq/(1-sp). Where delta p is the change in frequency of p. delta p = .000495/.999 = 0.0005. For the next generation: p' = p + delta p = 0.0015 q' = q - delta p = 0.9985 So, out of 1,000 individuals, there will be 1.5 with B and only 998.5 with A. Since you can't have a half individual, that means either 1 or 2. But let's continue this another generation: delta p = (1/2) (0.99 x 0.0015 x 0.9985) / (1 - 0.99 x 0.0015) delta p = 0.0015 so p" = 0.0015 + 0.0015 = 0.003 q" = .997 Now you have 3 individuals with B and only 997 with A. You can keep this up generation by generation and you will see that, eventually, all the individuals will be B and none will be A. Perhaps I did. But you said "In a perfect evolutionary world, random mutation would produce a new characteristic, then randomness would turn off, to allow that characteristics to be tested by natural selection." How did I misunderstand that? What did you intend to say? As I said, even in "perfect evolutionary world" randomness doesn't need to be turned off. The conceptual mistake you have is that "randomness" will destroy an individual or an individual RNA molecule. See below. 1. You are working with RNA world. There are other scenarios for early evolution. And no, random nucleotide assembly in this scenario does not destroy the RNA replicator. Random RNA sequences are not going to destroy other RNA sequences. The random sequences simply use resources (the nucleotides) that the replicator would use. So the calculation would be the frequency of the replicator (p) vs the frequency of the sum of all the random sequences (q). You have it backwards. The math for population genetics was derived from the universal of Mendelian genetics. So the math is universal. What was then done was look at many real world populations (at random) to see if they conformed to the universals of the math. And yes, they do. But this leaves you open to GIGO. And I think this is what happened to you, for the reasons I've tried to outline above.
  11. The article doesn't do that. Instead, it says that there were pygmy H. sapiens also in Indonesia 1400 years ago. The new bones 1) aren't in the same time frame and 2) don't have the distinctive features of H. floriensis. http://www.sciencemag.org/cgi/content/full/316/5821/34?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&andorexacttitle=or&andorexacttitleabs=or&fulltext=hobbit+people+Indonesia&andorexactfulltext=and&searchid=1&FIRSTINDEX=0&sortspec=relevance&fdate=7/1/1880&tdate=3/31/2008&resourcetype=HWCIT "The diminutive human who lived on the Indonesian island of Flores 18,000 years ago has been called many things: a pygmy, a diseased Homo sapiens, a hobbit. Now, in a report that was the talk of the Paleoanthropology Society's annual meeting here last week, a postdoctoral researcher claimed that the shapes of the fossil's wrist bones are so primitive that it cannot be H. sapiens. " The bones of the new finds have the shaped of H. sapiens, so the article implies. "When Tocheri first saw casts of the hand bones at a lecture last fall, he was struck immediately by their primitive shape. In his Ph.D. dissertation from Arizona State University in Tempe--which he is defending this week--he used three-dimensional imaging to analyze an innovation in the modern human hand. Living people and our most recent ancestors possess a complex of five bones that mesh together to ease stress on the wrist when the hand is used forcefully, for example in pounding large tools or in precision work. Neandertals had this derived shock-absorber complex, too; it is first seen in the hand of an 800,000-year-old human ancestor, H. antecessor, from Atapuerca, Spain. But the bony complex is not found in apes or earlier human ancestors, including H. habilis, which lived 1.75 million years ago in Africa. That species did use tools, but the shape of its hand bones does not distribute force away from the base of the thumb and across the wrist as efficiently as in modern humans. Tocheri got permission to study high-quality casts of the Flores bones, which were made for Stony Brook University biological anthropologist William Jungers. What Tocheri saw confirmed his impression that three bones in the wrist closely resembled those of an ancient hominid, not modern humans. Tocheri ruled out that the primitive hand bones were altered by disease because their distinctive shape develops in the first trimester, long before deformation from most diseases begins later in pregnancy or after birth. He also says known diseases do not reproduce the primitive bone shapes. " "That fits with emerging evidence from the long limb bones, which show no pathology either, says Jungers (Science, 19 May 2006, p. 983)."
  12. No. Skin color is related to the amount of sunlight in a region. What will happen is interbreeding between immigrants and "natives". Normally, northern Europeans would be geographically isolated from people in Africa and Central Asia -- which is how the skin colors evolved in the first place. Now, however, everyone is meeting in the same geographical location -- the USA or Britain or other places. So we will see what is known in evolution as "gene flow". This means mating between Africans and northern Europeans. The distinctivenss of skin color will be lost as the alleles for skin color are mixed and matched in the offspring. Since skin color is dependent on several (I think 7) alleles, you will see more and more people with intermediate skin color as they have some alleles for dark skin and some for lighter skin.
  13. A bit too simplistic. A characteristic needs to improve the organisms ability to earn a living. The result of that is differential reproductive success. Notice that. It's not that the individual replicates more than other individuals, it's that the individual's offspring contribute more to the next generation than the offspring of other individuals. Fitness is defined as the frequency of trait/allele observed divided by the frequency of trait/allele as predicted by Hardy-Weinberg. The unit of selection is the individual, not the species. The individual either thrives or fails to thrive. Any "species" success is simply the cumulative success of the individuals, not something unique at the species level. Define "insignificant". Actually, it's not. The equations of population genetics are very clear: a trait that has any positive fitness will be selected for and will, eventually, become fixed in the populatoin. The "threshold" is fitness = 1. Any value greater than 1 is going to result is selection and eventual fixation. It's very simple. Mendelian genetics makes it simple. Basically, Hardy-Weinberg states that the frequency of an allele/trait in a population will remain constant. In fact, most alleles/traits are in Hardy-Weinberg equilibrium most of the time. LOL! It isn't necessary for "randomness" to be turned off. Remember, natural selection is a two step process: 1. Variation (of which mutations are a part) 2. Selection. Selection is ALWAYS non-random. So it doesn't matter how many "random" variations there are in a population, selection will sort thru them all and pick the best one. Static populations are the norm! This is the basis of natural selection. An environment has only so many individuals that it can support. More individuals are born in a generation than the population can support. This is the basis for selection. Since only X number can be supported, and X + Y are born, then Y must be eliminated by competition. From your website: "You can watch this replicator organism turn the field red as it consumes all the available nutrients then turn the field dark green as it takes on its first advantageous mutation and passes it to all of its offspring. " No wonder your simulation led you to erroneous conclusions. You don't have selection. What you have is a phenonmenon called "boom and bust". This is when a population is in a limited area and limited food supply but there is no competition, no selection. It happens to deer on isolated islands with no predators. The population expands until it eats all the food supply, then collapses. You don't have competition or selection, but simply a program to see which can replicate the fastest.
  14. First, "randomness" is used specifically in evolution. Lots of people misuse the word, and that is where a lot of the confusion lies. For instance, the phrase "Given that much of evolutionary change is ultimately driven by, or is the result of, random processes rather than selection acting alone" misportrays the role "random" plays in natural selection. Natural selection is a two step process: 1. Variation 2. Selection. The variation is "random". That is, individuals in the population vary randomly with respect to the needs of the individual or the population. Selection is totally non-random. Selection never acts "alone"; it must always be coupled with variation. No variation, no selection (among variants). Second, natural selection does indeed have a "purpose", a short-term purpose. And that purpose is to design the population to cope with the present environment. What is overlooked is that natural selection is an algorithm (unintelligent process) that gives design. Once that is understood, everything else becomes clear. The environment presents design problems to the population. Natural selection solves those design problems, allowing the population to survive and prosper. When people say natural selection has no "purpose", they mean no long-term purpose. Natural selection cannot "see" ahead to future environments. So it cannot "plan" for them and get the population ready for those future environments. Dawkins made the use of the word "random" in evolution very clear: "Darwinism is widely misunderstood as a theory of pure chance. Mustn't it have done something to provoke this canard? Well, yes, there is something behind the misunderstood rumour, a feeble basis to the distortion. One stage in the Darwinian process is indeed a chance process -- mutation. Mutation is the process by which fresh genetic variation is offered up for selection and it usually described as random. But Darwinians make the fuss that they do about the "randomness" of mutation only in order to contrast it to the non-randomness of selection, the other side of the process. It is not necessary that mutation should be random in order for natural selection to work. Selection can still do its work whether mutation is directed or not. Emphasizing that mutation can be random is our way of calling attention to the crucial fact that, by contrast, selection is sublimely and quintessentially non-random. It is ironic that this emphasis on the contrast between mutation and the non-randomness of selection has led people to think that the whole theory is a theory of chance." R Dawkins, Climbing Mt. Improbable, pp 80- 82.
  15. That only pushes the problem elsewhere. How did life arise in the universe from non-life? Pioneer, please don't take this wrong, but please read a bit about biochemistry and, particularly, the Krebs cycle and the electron transport chain. You are trying to re-invent the wheel but you are making a square wheel, not a round one. Look instead at what is already known. Yes, a proton (hydrogen) is involved, but it is as part of the molecule nicotinamide adenine dinucleotide (NAD). Thus the proton is transferred to oxygen to make water. BUT, this process is coupled to the chemical reaction of combining adenine diphosphate (ADP) to adenine triphosphate (ATP). The terminal phosphate bond is the one used to "store energy" and is used in other anabolic reactions thruout the cell. http://library.thinkquest.org/C004535/aerobic_respiration.html That doesn't happen. The H-O bond is quite stable. Look at how much energy you must pump in via electricity to split a water molecule to hydrogen and oxygen! You are correct that the electrons in that bond spend more time around the oxygen nucleus than around the hydrogen proton. This gives that proton a partial + charge, since the negative electron isn't always there. The oxygen gets a partial - charge. What this means is that the H of one water molecule tends to "bond" with the oxygen of another water molecule. These "hydrogen bonds" do form and break many times a second. They are what gives water its unique properties as a liquid. The energy of a hydrogen bond is about 4.5 kcal/mole compared to 110 kcal/mole for the H-O bond. Usually, no. In most cells metabolism reaches the highest levels when the cells are synthesizing extracellular matrix or doing its job. For instance, in osteoblasts metabolism is maximum when the osteoblast is making bone matrix. In liver, metabolism is highest when hepatocytes are making albumin or detoxifying chemicals. It can't be. Evolution is about populations of individual organisms changing due to descent with modification. You are talking about what happens within individual cells. It's a nice little fantasy you have about H fighting O, but it has no connection to reality.
  16. Life doesn't appear from "nothing". Life on this planet is a set of chemical reactions. The sum of those chemical reactions (including the reaction of some molecules with each other and water to give a membrane) is life. This is what biochemistry is all about: studying the chemistry of living organisms. So far, we haven't found anything that is not covered by chemistry. As to how to get life from non-living chemicals, there are several possible ways to do this. The one I like best is "protein first". Heat a mixture of amino acids to have them form proteins. The proteins will then spontaneously form cells. The cells are alive. You can do this dry (as in a tidal pool) or at underwater hydrothermal vents. http://www.siu.edu/~protocell/ http://www.theharbinger.org/articles/rel_sci/fox.html This is where the all four of the characteristics come in. Storms do respond to stimuli (winds), and grow. However, they don't reproduce and they don't anabolize. Fire is another good example. Fires grow, respond to stimuli, reproduce, but they have only half the requirements of metabolism. Fires metabolize, but they don't anabolize. This is different. Once again, we are talking ethics and legality, not biology. When you say "human alive" you mean: when do we give the organism the rights and priviledges we have decided go to other members of our species? This isn't a biological question. It is often deliberately confused with biology so that a particular ethical/legal stance can be disguised as science, but that doesn't make it biology.
  17. Good question. I do this all the time with the adult stem cells. Are they still "alive" while frozen? They don't have any of the 4 characteristics; they are frozen. When I thaw them all the characteristics return. So, how do we consider this? Do we go from "alive" to "non-alive" while they are frozen and then back to "alive" again when they are thawed? Or do we consider them as generally "alive" but in an artificial state while frozen? This is a lot like "angels dancing on the head of a pin" when applied to frozen cells. It's just not important. However, when we get to humans we run into those ethical and legal minefields again. We've already seen the controversy over frozen blastocyts generated during in vitro fertilization. And the controversy just gets worse if we try freezing adult humans. Are they still "human" while frozen?
  18. The article is in Science, which will be in your local library. 8. http://www.sciencemag.org/cgi/content/full/312/5770/97 JT. Bridgham, SM Carroll, J W Thornton Evolution of Hormone-Receptor Complexity by Molecular Exploitation Science 7 April 2006: Vol. 312. no. 5770, pp. 97 - 101 There are some other papers that trace the molecular evolution of enzyme systems. For instance, evolution of the blood clotting system (one of Behe's original IC structures) is summarized here: Thromb Haemost 1993 Jul 1;70(1):24-28 The evolution of vertebrate blood coagulation: a case of Yin and Yang. Doolittle RF That one might be tough for you to find. PM me with your e-mail address and I can send you the PDF file. A paper summarizing the different routes of Darwinian evolution (with lots of references) is here: http://www.cbs.dtu.dk/dave/JTB.html Other papers looking at the evolution of protein shapes are: 1. E Wilson-Miles and DR Davies, On the ancestry of barrels. Science 289: 1490. Sept. 1, 2000. "the structure arose from the duplication and fusion of the gene of acommon half-barrel ancestor" 3. http://compbiol.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pcbi.0030139 Formation of gene families and protein folding
  19. In the context of abiogenesis (life from non-life), the definition is usually that something alive must have all four of the following characteristics: 1. Metabolism (anabolism and catabolism) 2. Response to stimuli 3. Growth 4. Reproduction. I said "usually" because many researchers in the abiogenesis field have added a characteristic: 5. RNA/DNA directed protein synthesis Some researchers add the characteristic" 6. Has a lipid bilayer membrane. Or at least a means of separating the living thing from it's environment. Some people have proposed micropockets within rock formations. Other researchers eliminate conditions 1-3 and say that something is "alive" if it can self-replicate. Lokanath, "evolution" doesn't have the definition in science that you have given it here. Neither does "involution". "involution" in biology refers to tissues folding in upon themselves to make a pocket. Before you try imposing your particular views upon biologists and state those opinions as "fact", you need to learn first what has already been done in the field of abiogenesis and biology. Otherwise all you are doing is spouting nonsense. In another thread I already showed that your definition and application of "subtle form" is contradicted by observations. Sorry, but this just isn't "life".
  20. The definition isn't about what life is "made of". It's about the characteristics an entity must have in order to be alive. The entity can be made up of anything or combination of things -- as long as it has those 4 characteristics. The amazing part is that it is very simple to get that complexity. That "complexity" arises out of chemistry. Read this: http://www.theharbinger.org/articles/rel_sci/fox.html and we can discuss it in more detail if you want. But the key here is that when you chemically put amino acids together to make proteins (by heating them), they do not form random proteins. Instead, there is internal ordering due to the side chains of the amino acids. AA are not like playing cards. Therefore, when proteins are made by heating them, it is certain that they will have a biological activity (or maybe more than one). The range of biological activities include catalyzing the reactions that make up metabolism.
  21. "Life" has a simple definition. Life is an entity with all 4 of the following characteristics: 1. Metabolism 2. Growth 3. Response to stimuli 4. Reproduction The issue here is that the question "when does life start?" is not a biological question. The question in the OP applies to human life and is an ethical and legal question. When in the continuum of conception to death do we apply the legal rights and protections that we think ought to be applied to members of our species? That's untrue. Many processes are only loosely defined and controlled by genetic factors. For instance, the molecules that give the mechanical properties of the cartilage in your joints are proteoglycans. Proteoglycans are very complicated molecules, consisting of a protein core to which are attached long sugar molecules called glycosaminoglycans. Glycosaminoglycans are assembled by enzymes. But the length and number of the GAGs vary from proteoglycan to proteoglycan molecule. Take a biochemistry course. You will find that we do understand the metabolic processes. What is being worked on now are the various control levels for those metabolic processes. But the metabolic process that is the Krebs cycle, for instance, is "completely" understood. The science contradicts this. The tree is not available in a "subtle form" as you define subtle: "matter is the form of existence where subtle sub atomic particles join by energy bonding and when it comes to the molecular state it is detected. When it lose its form it goes back to its subtle form " The molecules in the seed are not in sub-atomic particles. The DNA, proteins, and sugars in the seed are in a "molecular state". Therefore the data falsifies your theory. I suggest you do a bit of studying on embryonic development instead of trying to impose your philosophy on the physical universe.
  22. No space, no time, no matter, no energy. What would that "look" like? Beats me. I can state it, but not really imagine it. Since there would be no electromagnetic energy (light), you wouldnt be able to "see" anything. No photons to interact with your eyes. Bettina, this is different than "bubble universe". "“The multiverse is like a bubble bath,” with a bubble representing each universe, he added. There are “multiple universes bubbling, colliding and budding off each other” all the time. Another panelist backed the multiverse idea, but three more insisted there’s virtually no evidence for the highly speculative concept." In multiverse, each universe with space, time, matter, energy is self contained. A "bubble" would be the universe we see around us. In bubble universe, there is only one universe with space, time, matter, and energy. Instead, there are "pockets" within that big universe that are invisible to the others -- because space is expanding faster than the speed of light. In multiverse, there is no way to contact any of the other universes. Notice that comment that multiverse is VERY speculative. It's a fun idea to play with mathematically but there is no observational data to support or refute it.
  23. Because to be "outside" in the normal sense means to have spacetime beyond the boundary. And spacetime means the 3 dimensions of length, width, and height. However, since the universe contains ALL the length, width, and height, there are none of those dimensions "outside" it.
  24. No, you won't. Because right next to the article is a section called "Related Articles" that provide some of the experiments. Here's just one: http://www.ncbi.nlm.nih.gov/pubmed/9355215?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVAbstractPlusDrugs1 "CONCLUSIONS: This study demonstrates the reproducibility of a rabbit fusion model, and the ability of a pulsed electromagnetic field to induce a statistically significant increase in stiffness, area under the load-displacement curve, and load to failure of the fusion mass. This investigation provides a basis for continued evaluation of biologic enhancement of spinal arthrodesis with the use of a pulsed electromagnetic field." What you need to do is search "electromagnetic, field, bone" and then hit the tab "Limits". Check "human" and "clinical trial". You end up with 25 references. ONE of them is at http://www.ncbi.nlm.nih.gov/pubmed/15986086?ordinalpos=2&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum If you do "electromagnetic, field" with the same limits, you get 239 papers. Many of these have to do with environmental exposure to magnetic fields, but there are several clinical studies on pulse electromagnetic fields. One looks at spinal fusion with PEMF: http://www.ncbi.nlm.nih.gov/pubmed/12131732?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVAbstractPlusDrugs1 If you really want to look at the data, you can't just look at ONE paper and dismiss it as "theoretical" while passing on the large number of clinical and animal studies.
  25. I never said he shouldn't do it. I only pointed out the historical record in regard to physics that major contributions have been made before the age of 30. It doesn't mean that 1) he can't have a rewarding career teaching and doing physics. 2) he can't be the exception that tests the rule. After all, the important thing is going for your dreams and finding a career that you enjoy. My only concern is graduate school admissions committees for physics. In biomedical sciences, we have admitted people over 30 years old --because people in the biomedical field often make their most significant contributions in their 50s and 60s. Physics admission committees may be different -- or maybe not. No way to know until he tries. Wanderer, Atheist has a good point: don't label yourself as "extremely intelligent". Let other people reach that conclusion based on your record. Your grades, Graduate Records Examination scores, and any research you do as an undergrad are going to be indications of your intelligence. BTW, going to classes is going to be necessary to prepare for the GRE. In Einstein's day you could get admitted to a university program based on professors knowing you. Today the GRE is an essential part of the process. Get a low GRE and you won't make it into grad school. So attend college for 1) personal interaction with physicists and 2) classroom experience so that you will be prepared for the GRE. Just reading books by yourself isn't going to be enough for those.
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