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Everything posted by lucaspa
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He's not talking about gravity. He's talking forces on the cell. Those forces are often exerted thru the proteins that attach the cell to the extracellular matrix: "The model's attachment to the flat cloth is analogous to the adhesion receptors (integrins) which physically connect a cell to an anchoring basement membrane substratum. " Endothelial and smooth muscle cells are subjected to flow forces as they are attached to the matrix of an artery. Quite a bit. It's also correct that "nuclear and cellular gene expression is changed due to the architectural configuration and the environment of the cell. " This has been known for 20 years in the field of cartilage biology. Grow chondrocytes on plastic and they flatten out, express collagen type I, and small proteoglycans. Change the shape by growing chondrocytes in agar or coating the plastic with HEPES and the cells are spherical, synthesize type II collagen, large aggrecan, and generally make a cartilage matrix. You can take them thru several cyles of regular plastic and HEPES plastic and have them flatten and behave like fibroblasts and then behave like chondrocytes. I've attended a couple of talks about cell shape and tensigrity and the data seems valid.
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The pore size of a 2% agarose gel would be smaller than a 1% agarose gel. More agarose, denser the agarose molecules and the smaller the pores between them. No matter the voltage, you can track the migration of DNA thru the gel with the dyes bromphenol blue and xylene cyanol. http://www.vivo.colostate.edu/hbooks/genetics/biotech/gels/agardna.html However, "As the voltage applied to a gel is increased, larger fragments migrate proportionally faster that small fragments. For that reason, the best resolution of fragments larger than about 2 kb is attained by applying no more than 5 volts per cm to the gel (the cm value is the distance between the two electrodes, not the length of the gel). " I would suggest you do 5 volts per cm.
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are attitudes hereditary?
lucaspa replied to cameron marical's topic in Evolution, Morphology and Exobiology
I'd be careful about "attitudes". That your father has a particular "attitude" toward sports cars does not mean you will have one. However, since temper is mediated by chemicals in the brain and the level of those chemicals and the magnitude of their action mediated by receptors -- both of which are genetic -- then yes, you could end up with the same type of "temper". The Nov. 7, 2008 issue of Science has a special section "Genetics and Behavior". I've attached the PDF file of the general overview to the post. Those interested should find it helpful. Parsing the Genetics of Behavior.pdf -
Mutation rates vary from species to species. Bacteria have the lowest and humans have the highest. In actual fact, each human has about 20 mutations. The paper you want is: PD Keightley and A Caballero, Genomic mutation rates for lifetime reproductive output and lifespan in Caenorhabditis elegans. Proc. Natl. Acad. Sci. USA 94: 3823-3827, 1997 This study documents the rate of deleterious mutations in the worm C. elegans. Because they are hermaphroditic, the authors were able to separate the worms and run parallel populations descended from a single individual. By maintaining independent sublines, the effect of selection could be minimized, and thus the deleterious mutations could be kept in the population. Lethal mutations are still lethal, but the experimental design allows accumulation of deleterious mutations (as well as neutral mutations) and then the effect on lifespan and production of viable offspring, both of which are measurements of fitness. The estimated deleterious mutation rate per haploid genome (the whole organism) was 0.0026, or 2.6 per thousand. Right. Hunting is a way for lions to earn a living. But instead of backing away from "design", I strongly suggest you face it directly. Natural selection is an unintelligent process that produces design. Yes, lions are designed for hunting. Designed by natural selection. Eyes were designed by natural selection for seeing, placentas for nurturing unborn young, etc. Natural selection does have a short-term goal or purpose: designing the population for the particular envioronment. NS cannot have a long-term goal, simply because NS can't "see" ahead to what future environments will be. But in emphasizing that NS has no long term goal, we have unfortunately thrown the baby out with the bathwater and ended up falsely declaring that NS has no purpose whatsoever.
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Each chromosome is one DNA molecule. We have 23 pairs of chromosomes (1 of the pair from each parent) for 46 chromosomes. So we have 46 DNA molecules per cell.
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Is there a scientific case for an Intelligent Designer?
lucaspa replied to Alan McDougall's topic in Speculations
Sorry, but I do know better. What you haven't realized is that "invisible pink unicorn" is falsified. Think about it. Color comes from the wavelengths of light reflected off an object. If something is invisible it isn't reflecting light, therefore it can't be pink. Once again I'll post this: "1. Tachyons: can we rule them out. The special theory of relativity has been tested to unprecedented accuracy, and appears unassailable. Yet tachyons are a problem. Though they are allowed by the theory, they bring with them all sorts of unpalatable properties. Physicists would like to rule them out once and for all, but lack a convincing nonexistence proof. Until they construct one, we cannot be sure that a tachyon won't suddenly be discovered. 3. Time travel: just a fanstasy? The investigation of exotic spacetimes that seem to permit travel into the past will remain an active field of research. So far, the loophole in the known laws of physics that permits time travel is very small indeed. Realistic time-travel scenarios are not known at the time of writing. But as with tachyons, in the absence of a no-go proof, the possibility has to stay on the agenda. So long as it does, paradoxes will haunt us.'' Paul Davies, About Time, 1994. Think about tachyons for a moment. Invisible (because they travel faster than light, they cannot interact with our retinas), undetected and undectable by any conceivable instrument, no effect on the universe that we have ever observed, and a pain in the butt. What's our scientific attitude toward tachyons? Do we treat them as you apparently want to treat IPU, that is, say they don't exist? Or do we consider them a possibility until we can falsify them? A major problem with dismissing things without being able to falsify them is the same problem that several people have ascribed to ID: stopping science. If you dismiss possibilities prematurely, you bring science to a halt as surely as stopping the search for a material cause. Merged post follows: Consecutive posts merged The Strong Anthropic Principle is an error in logic. The AP itself is a very useful tool for testing theories. So, let's look at the SAP and the AP: SAP: "If our existence depends on the fine tuning of the universal constants, and we exist, then, since we exist, those constants must be fine tuned. " AP: "It must be the case that: if life depends on the fact that the physical constants are fine-tuned, then, since life exists, those constants have those values." Notice the difference. The AP becomes very useful in the intial testing of new cosmological and quantum gravity theories: if the mathematics give a universe where life can't exist, then the theory is wrong. In historical fact, the AP was used to test and reject the initial versions of String Theory and No Boundary. The problem with the SAP is that word "must". The SAP has the logical necessity couched in erroneous language. The universe is not required to have the constants it does. If it had different constants, we simply would not be here to observe it. So the SAP is bad logic. The problem is that science does not like to accept the "won the lottery" answer when there was only one ticket sold and it happened to match the number drawn by random. So the search for explanations why the universe has this set of parameters out of an infinite possible set of parameters. Thus we have multiverse and bubble universe and quantum splitting universe. All of these generate an infinite number of universes. Now it becomes virtual certainty that one of the universes will have these parameters just by chance and, of course, we happen to be in that universe. Another approach is to find an underlying theory where the apparently arbitrary parameters are not arbitrary but determined outcomes of the deeper theory. This is one reason why String Theory has been so attractive: many of the arbitrary fine-tuned parameters are determined by the properties of strings and 'branes. And then, of course, is the hypothesis that the universe was created by an intelligent agent who chose the parameters so that the universe would have life. Lots of theories and insufficient data to choose among them. However, what I see in several of the posts is an attempt to make "predictions" or "observational consequences" a criteria to be a scientific theory. By this is meant a prediction other than what we currently observe. IOW, a new Demarcation Criteria is being proposed to separate science from non-science. I submit that this criteria isn't going to work any better than any of the previous proposed criteria. Many theories that we consider scientific do not predict data different from what we already observe. A prime example of that is Hartle-Hawking-Turok's No Boundary. The concepts and parameters of imaginary time are chosen precisely to produce the universe we see. Initially, Hartle-Hawking seemed to predict a universe that would expand and then collapse. When it was found that the universe would expand forever, Turok helped modify No Boundary so that it applied to an ever-expanding universe. The analogical shape was no longer a sphere but a hyperbaloid. No one has suggested or would countenance throwing No Boundary out of science. So the criteria fails. What's more, you have ideas that no one would ever consider to be science that do predict data we haven't seen yet. An extreme example would be Millenialism, which predicts that Yahweh will end the universe and predicts exactly how that will happen. No one would include Millenialism within science. Merged post follows: Consecutive posts merged That is not all the options. The methods used become a new option. You limit the options by saying "designer" or "chance". 1. You can have non-chance but not a designer. 2. You can also have a designer that works by the processes discovered by science. In this case, the hypothesis does not include everything. For instance, a modified ape would not be intended, but life would be. What has been noticed is that several of the physical parameters of the universe need to be very precise if the universe is to produce life. Change those parameters by 1 part in a billion (some less, some quite a bit more) and life could not have happened in the universe. It appears that the those parameters are arbitrary. That is, they are independent of any other physical process or equation. So the question arises: why does the universe have these parameters. As I noted above, there have been several hypotheses proposed as possible answers: 1. There are a VAST number of universes (perhaps infinite) each with different parameters. Therefore it is certain that one of them will have the parameters in this one. 2. The parameters are not arbitrary. Instead, they are determined by more basic properties of the univeres, i.e. the properties of strings. 3. An intelligent entity chose the parameters when it created the universe. -
The reason you get a pattern is that you have introduced non-randomness into the process: "measure halfway to the corner chosen by the cube". Instead of randomly measuring, or measuring distance based on the number on the die (say centimeter corresonding to the number on the die), you non-randomly always measure "halfway to the corner". ALWAYS. So of course a non-random pattern emerges from a non-random process. What we often mean when we say "random" is "unpredictable". Gould was trying to make the point that evolution was a totally unpredictable process. However, Gould ignored that there are some non-random factors involved in evolution. These non-random factors are the constraints of physics and chemistry. Thus, physics determines that there are only a few shapes for a predator who moves in water. There are constraints because the predator has to 1) move fast, 2) be maneuverable and 3) position its mouth to be able to grab prey. Thus we have ichthyosaurs, sharks, and dolphins all with the same basic shape. And yes, there are unpredictable processes/events, particularly at the quantum level. Which particular atom of a radioisotope will decay next is completely unpredictable. In the aggregate, half the atoms will decay in a half-life. So radioactive decay is regular, but unpredictable. Merged post follows: Consecutive posts merged Quantum mechanics has shown that, for quantum events, its not a matter of information. In terms of indeterminancy of complementary properties -- such as the position and momentum of an electron -- the information doesn't exist. If you know precisely the position of an electron, the momentum can't be known. For the unpredictable events I mentioned at the quantum level -- such as radioactive decay -- it is also not a matter of just don't have "enough information". The information doesn't exist. Physicists have looked extensively for ways to get the information, but it's not there. Welcome to just as much faith as you think Thief is showing. Sauce for the goose.
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No. Instead natural selection is a two-step process: 1. Variation between individuals. 2. Selection. Mutations are one type of variation. Evolution is "descent with modification" and applies to populations. According to Mendelian genetics, the proportion of individuals in a population with a trait or a particular allele will remain constant from generation to generation. It's called the Hardy-Weinberg Principle and most genes of most organisms are at what is called the Hardy-Weinberg equilibrium (unchanging) most of the time. Populations can change over generations due to the following reasons: 1. Genetic drift (chance). 2. Gene flow from one population of a species to another. 3. Sexual selection. 4. Natural selection. Any and all of these will result in "descent with modification". That is, any and all of these will change a population over the course of generations. However, only natural selection is responsible for the designs in organisms: wings for flying, eyes for seeing, blood clotting cascades, immune systems, etc. Sorry, but that is incorrect. I urge you to read the references I gave you that document otherwise. If you are going to be a programmer, you need to be aware of this and the potential in order to be competent in the field. Merged post follows: Consecutive posts merged That example was never used in the PBS series on evolution, because it never happened. Instead of "genes being actived [sic]" implying that the gene had been there but dormant, instead say that genes have different alleles -- forms of the genes. The gene for color was changed (by mutation) and the new form -- allele -- of the gene had a competitive advantage over the old allele. Over the course of generations, the new allele replaced the old allele. So now the frogs were different from their ancestors..
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That is an ethical problem with animal research as compared to human research: animals cannot give informed consent. It is an ethical problem that has been extensively discussed in the scientific and medical communities. The consensus is that the reduced cognitive abilities of other species compared to humans is one reason why research using them is justified. IOW, the very inability to understand and give informed consent places animals outside the ethical principles we are required to use for members of our own species. All species exploit other species, especially animal species. In order to survive, animals must cause the death and dismemberment of other species -- either plants or animals. We don't hesitate to rip a corn plant out of the ground (killing it) because the corn plant is unable to give "informed consent" to its use as food for us. Bottom line: the idea of informed consent is an ethic that applies only within our own species, not between species.
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Is the fallback position valid? What you have supposedly done is eliminate all possible experimental data for "mass curves spacetime" when you say " it describes a mechanism that could guide mass through space in the same way that curved spacetime does" We need to see those equations or whatever, because, as you should know, one of the very strong supporting pieces of data for Relativity and bending of spacetime is the displacement of the apparent positions of stars during the 1919 eclipse. The positions were displaced because the path of the light was bent in the spacetime around the sun. So, it would help you case if you could show the calculations from your theory that gives the same apparent displacement of those stars as was observed then. Or, for other examples, see this site: http://undsci.berkeley.edu/article/natural_experiments What more? Please be specific. It would help if you could give quantitative predictions of data we should find if your theory is correct. Data that would be different than we would find with General Relativity. Your idea needs to have equations that are better at predicting gravitational effects. So what are those equations from your theory? Gravity so far has resisted every attempt to quantize it. What is the quantization of the mass? How does the mass of the aether change? What happened to friction in an atmosphere? Also, let's take a rocket in vacuum. The rocket is emitting reaction mass and the velocity or the change in location in the mass seems to be determined by the amount and velocity of the emitted reaction mass. After all, in the same general location in the universe, the energy density of the aether would be the same, but the change in location of the mass can be changed by increasing the velocity of the emitted reaction mass. That seems to falsify your theory.
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Well, the chemicals are not "random". Chemistry isn't blind chance or randomness. Chemicals don't react with other chemicals "randomly". The products are not random. So, when amino acids are heated they polymerize to form proteins. The amino acid sequences in those proteins is not random. It is determined by the side chains (R groups) on the amino acids. There are lots of possibilities for amino acid sequences, but not "random". Also, any protein will have a biological activity. A particular protein may not have a specific biological activity, but it will have an activity (or more than one). If quadrillions of proteins are made (as they are when the "soup" is heated), then it is virtually certain that one or more of the proteins will have every biological activity necessary for life. Also, when the proteins are exposed to water, the reaction is not random. The chemistry of the proteins and water determine that the proteins will make a cell -- a living cell. Once you have a living cell, then evolution is not random, either. The selection part of natural selection is the opposite of random: deterministic. Think of a Library of Mendel. It is the library of all possible genomes. It is VAST, but finite. Think of wings going off in mathematical dimensions. There is a hallway of all possible H. sapien genomes, in a wing of all possible hominin genomes. There are going to be many hallways containing genomes that will code for organisms who "can understand the mysteries of the universe, know love, and understand the value of life". As evolution explores the Library of Mendel, it is inevitable that it will eventually find one or more hallways of genomes for such organisms. (credit to Daniel Dennett for the "Library of Mendel" concept). Merged post follows: Consecutive posts merged LOL! The "accurate predictions" are failed attempts to disprove it. Mr Skeptic, first you formulate a hypothesis/theory. Then you assume the theory is true. With that as a premise, you deduce consequences of the theory. Those consequences are "predictions". We then go looking for the consequences (predictions) in an attempt to disprove the theory. This is all based on deductive logic: true statements cannot have false consequences. If you find false consequences, the theory is wrong or disproven. It's not that evolution is a "superior theory", but rather that intelligent design/ creationism has been disproven. Past tense. ID/creationism has false consequences. You noted one of those false consequences: retroviral insertions. Retroviral insertions are not a consequence of ID/creationism. They cannot arise under that theory. Therefore their presence disproves ID/creationism. Merged post follows: Consecutive posts merged Most of the errors in copying DNA are repaired. The errors that are not repaired are mutations. No error-correcting system can be perfect. An system that was 100% perfect in correcting errors would violate the 2nd Law of Thermodynamics No. No evolutionist ever claimed this. And yes, we do find new parts under construction in fossil organisms. The transition from reptilian jaw to mammalian middle ear is one example. There are also fossil imprints of feathers in construction. Remember, mutations are beneficial, harmful, or neutral in respect to a particular environment. A mutation that is neutral in one environment could be very beneficial in another. In fact, some people have a mutation that confers resistance to HIV. In the absence of HIV this mutation is neutral -- it neither helps nor hurts the immune system. But when HIV is part of the environment, now the mutation is beneficial. What happens most in evolution is exaptation. That is, a trait is built for one purpose and then also has another purpose unrelated to the initial selection for the trait. Two good examples are the evolution of flight in insects and birds. In insects, wings are modified gills. Wings were enlarged to act as heat exchangers. Just at the optimal size to function as heat exchangers, they structures also got the insect off the ground into flight! In birds, feathers evolved first for sexual display but they also served as insulation. Later on in small theropod dinosaurs, feathers assisted the animals to run up inclined surfaces -- either to catch prey or run to a refuge to escape a larger predator. Pumping the forelimbs up and down on these bipedal dinosaurs allowed them to run up surfaces that were past vertical! BUT, at this point the feathers -- evolved to do this -- also got the dino off the ground into first flight! What you have, MustKnow, is a lot of misinformation about evolution by people who want to reject it for religious reasons. For instance, from the newgeology website: "All known mutations in animal and plant germ cells are neutral, harmful, or fatal. " Not true at all. I have a list of over 60 papers describing beneficial mutations. What's more, this paper notes that only 2.8 mutations out of 1,000 are actually harmful. PD Keightley and A Caballero, Genomic mutation rates for lifetime reproductive output and lifespan in Caenorhabditis elegans. Proc. Natl. Acad. Sci. USA 94: 3823-3827, 1997 So, have you read any textbooks on evolution? Or do you confine your reading to anti-evolutionist websites? I strongly suggest Douglas Futuyma's Evolutionary Biology. It will correct a lot of the untruths the websites are telling you. BTW, you mentioned computer programs. Yes, I have done that. However, are you aware of studies that people have used natural selection to make computer programs? One individual -- Al Samuel -- had natural selection make a computer program to play checkers. The program played checkers games and -- by variation and selection -- changed the program. Eventually, the program was able to defeat the human checkers champ. Samuel didn't look at the program while it was evolving. After the program won the checkers' championship, he looked it over. There were large segments of the programming that he couldn't figure out what it did. Which shows that Samuel's intelligence wasn't involved. After all, what programmer doesn't know what each line in the program does? If you want to read more about it: AI Samuel, Some studies on machine learning using the game of checkers. IBM Journal of Research Development, 3: 211-219, 1964. Reprinted in EA Feigenbaum and J Feldman, Computers and Thought, McGraw-Hill, New York, 1964 pp 71-105. Basically, MustKnow, natural selection is an unintelligent process that gives design. And it is a much better designer than humans.
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Actually, no. Single celled organisms are alive and are "just little cells full" of chemicals such that the cell can do the 4 activities that, together, constitute life. That's not a requirement. Look at the characteristics the define something as biologically alive. Those characteristics do not require genes to get the characteristics. What you've done is make a strawman requirement based on modern life. Still, I’ll respect your POV, made all the more credible by a recent article coauthored by Harold Morowitz. You do realize this is the Argument from Authority, don't you? I think you are thinking of an article in the June 2007 issue of SciAm, by Robert Shapiro. Remember my claim. I never claimed that protocells were actually how life started. I claimed that they are one way to get life from non-life. However, the ease with which protocells form and the resemblance of fossilized early cells to artificially fossilized protocells makes it likely that protocells from proteinoids was, at least, one of the ways early cells came into existence. And the protocells provide part of the "how". 1. The protocells will make DNA/RNA. Otherwise, there is no abiogenetic chemistry that will do this. 2. Because I agree. The chemistry to first make proteins from amino acids and then have them make cells is just too simple not to happen. Nope. You don't need that. The chemical interactions among the proteins and between proteins and water will build the cell. Reproduction also doesn't need a genetic language. Genetics (really what you are describing is "directed protein synthesis") evolves later and provides a selective advantage by reducing variation among offspring. Yes. It involves how proteins and the bases of RNA/DNA interact. The principle is hydrogen bonding. As noted, proteins with a lot of lycine will associate with DNA/RNA with regions of poly U and poly C. Proteins with a lot of arginine, OTOH, associate with DNA/RNA with regions of poly A and poly G. In terms of transfer RNA (the RNA in the cytosol that carries specific amino acids to the mRNA in ribosomes), work has been done associating conformation with specific amino acids bound to the tRNA and the hydrogen bonding to the mRNA codon: 4. Margaret E. Saks, Jeffrey R. Sampson, John Abelson Evolution of a transfer RNA gene through a point mutation in the anticodon. Science, 279, Number 5357 Issue of 13 March 1998, pp. 1665 - 1670 The protocells are not "chemical analogues", but real cells. Remember, the metabolic processes in cells -- such as the Krebs cycle -- are catalyzed by proteins (enzymes). As it happens, in the internal ordering of proteins as the form from amino acids, it is inevitable that you are going to get proteins that catalyze the chemical reactions in the Krebs cycle. The catalytic rate may not be great, but all you need is some catalytic activity. Better catalytic activity can be generated later by natural selection. Merged post follows: Consecutive posts merged Not necessarily. It can merely indicate an emotional need or bias overwhelming the intellect. I think we can all agree that Albert Einstein was one of the most intelligent people ever. Yet he too rejected a well-supported theory: quantum mechanics (even tho his Nobel Prize was for a paper laying the foundations of QM!). The indeterminism in QM conflicted with his emotional desire that the universe be determined: "God does not play dice." Merged post follows: Consecutive posts merged It does not have to be an "either-or" proposition. The RNA World could have been happening alongside the protocells. That is, RNA molecules could have been making 1) more RNA and 2) proteins. (Remember, all you need is the RNA in ribosomes to make a protein. It will not be directed by mRNA, but the ribosome will make protein without the mRNA.) The protocells could then have absorbed the proto-ribosome and had it making proteins inside the cell. BTW, if you want a step-by-step summary of how you get a "digital code" by Darwinian evolution and directed protein synthesis, read this article: 1. AM Poole, DC Jeffares, D Penney, The path from the RNA world. J. Molecular Evolution 46: 1-17, 1998. You'll probably have to go to a university library. I have a photocopy of the article but not a digital copy.
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You need to go back and look at the responses more. Several people are giving you evidence that contradicts your scenario. That means your scenario is not "compatible with existing science". There are no "personal interpretations" involved. I notice you did not document any of the "ifs" on which your logic hung. Without that you have nothing and your deductive logic can't be trusted. What it looks like you did is take some of the words we used -- such as "entropy" -- and just irrelevantly included them into your scenario. The First Law of Thermodynamics states that there is a finite amount of energy no matter how you define our universe. The problem is that many experiments with energy show that energy is not quantized in and of itself. Instead, the "quantization" comes from electrons dropping from higher electron orbits to lower ones, discrete chemical bonds formed or broken, and discrete amounts of matter converted to energy in nuclear fission and fusion. IF energy itself were quantized, there would be a common quanta in which each of these would be integers of that quantum. The data I have seen contradicts that. For instance, if an electron drops from a 2p to a 1p electron orbital, you get one quanta of energy. But if it drops from 2s to 1s, you get a different one that is not related by an integer to the first. If your scenario were correct, this should be the case. Then you are not saying anything new! I advise you to look at the First Law of Thermodynamics. We're done.
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Here I would disagree with the author based upon later interviews with gays. The change in attitude came about because of AIDS. Initially, gays did argue they didn't want to go for marriage. But then along came AIDS and suddenly gay life partners found themselves excluded by homophobic family members of the sick individual because they had no legal standing. So they were not allowed into hospital rooms because they were "not family", excluded from care and end of life decisions, excluded from inheritance of sentimentally valuable remembrances (and sometimes very valuable real property), etc. So gays changed their minds about marriage and wanted the legal protections and rights that go to spouses.
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JR Jungck and SW Fox, Synthesis of oligonucleotides by proteinoid microspheres acting on ATP. Naturwissenschaften, 60: 425-427, 1973. Fox, SW, Jungck, JR, Nakashima, T. From proteinoid microsphere to contemporary cell: formation of internucleotide and peptide bonds by proteinoid particles. Origins of Life 5: 227-237, 1974. You might also want to read this lengthy post based on Dose and Fox's book: http://www.asa3.org/archive/asa/199905/0230.html My recollection is that pigments -- flavines and pteridines --- are synthesized from the amino acids during the heating and can be detected in low quantities using mass spectrometry. Ah yes, here is part of it: http://www.springerlink.com/content/r673818865317433/ It is these flavines and pteridines that can also act in electron transport under the stimulation of light for a primitive form of photosynthesis. So we are not talking about porphyrins made by heating amino acids, but flavines and pteridines. This is why preparations of protocells are often pigmented. Porphyrins are made in the same chemical reactions that produce amino acids from methane and ammonia: http://books.google.com/books?id=LKy0weDEFp8C&pg=PA8&lpg=PA8&dq=porphyrins+synthesized+heating+amino+acids+proteinoids&source=bl&ots=4Ys8Ay8J7R&sig=X9JNzwx_71S4cIpe2uwhnFSreqk&hl=en&ei=LgLtSYryBduLtgfz4aTNDw&sa=X&oi=book_result&ct=result&resnum=3 The protoporphyrins can be incorporated into protocells when they are made. Protocells can form when there is a complex mixture of amino acids, sugars, nucleotide, fatty acids, etc. During the experiments, in order to get a level of activity that can be detected by the assays used, exogenous protoporphyrins were added. It's not photosynthesis the way modern cells do it, but it is conversion of sunlight, water, and carbon dioxide to storage molecules. "The early evolution of a photocatalytic system of the porphyrin type, able to efficiently collect and utilize solar energy for primary electron transfer is discussed. Experimental results concerning some spectral and photochemical properties of the porphyrins, biosynthetic precursors of chlorophyll and their complexes with polymeric templates are reviewed. Protoporphyrin IX associated with pigmented proteinoid is demonstrated to be a favourable candidate for a role of a photosensitizer of the first photosynthetic reaction centers. The origin and early evolution of the photosynthetic electron transfer chain and of the phosphorylating mechanism are discussed with emphasis on the energetic mechanisms of archaebacteria."
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Because you are on the wrong time scale. As even you admit, the latest data is from galaxies 2 million light years away. Yes, that's 2 million years ago in time, but the universe is 13.4 billion years old. It has been expanding all that time! 2 million years is a lot in terms of a human lifetime, but very little time in relation to the age of the universe. So, what would make us think that there would be something that just appeared within the last 2 million years that would not only stop the acceleration of the expansion we saw last, but cause it to start going backwards and collapsing? Let's see if an analogy helps. You are in a car and have been pushing on the gas for the last 5 minutes (300 seconds). The last measurement is 0.05 seconds ago and it shows you still accelerating (that is 0.00016 of the time you've been accelerating). The road is clear ahead of you, no obstacles. What would make you think that, in the last 1/20th of a second, an unknown force was not only stopping your acceleration, but actually causing you to go backwards?
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Is there a scientific case for an Intelligent Designer?
lucaspa replied to Alan McDougall's topic in Speculations
Exactly right! Science disproves entities. What we can't disprove remains on the table as a possibility. We can't "dismiss its existence". You and I can make a personal decision to believe it doesn't exist, but we can't, speaking for science, dismiss its existence. Let me give you just 2 examples: "1. Tachyons: can we rule them out. The special theory of relativity has been tested to unprecedented accuracy, and appears unassailable. Yet tachyons are a problem. Though they are allowed by the theory, they bring with them all sorts of unpalatable properties. Physicists would like to rule them out once and for all, but lack a convincing nonexistence proof. Until they construct one, we cannot be sure that a tachyon won't suddenly be discovered. 3. Time travel: just a fanstasy? The investigation of exotic spacetimes that seem to permit travel into the past will remain an active field of research. So far, the loophole in the known laws of physics that permits time travel is very small indeed. Realistic time-travel scenarios are not known at the time of writing. But as with tachyons, in the absence of a no-go proof, the possibility has to stay on the agenda. So long as it does, paradoxes will haunt us.'' Paul Davies, About Time, 1994. No one is saying there's certainty on the answer posited. The point is that you are dismissing the possibility of the answer based on unanswered questions if the posited answer is correct. You can't do that. If you hold to that criteria, then we have no even "certain" answers, because each answer is going to give rise to new questions. That's not what you were saying. You were saying that, because we didn't know "who designed the designer", then we can dismiss that there was an intelligent entity that created the universe. That you cannot do. You shouldn't even be bringing up "who designed the designer" now until we have some "certainty" that there was one. See your quote above. You are "dismissing its existence". However, the suggestion is an answer to the question: "why does the universe exist?" That we have a new question doesn't invalidate the proposal as an answer to the question posed. With respect, IDers have defined the "designer" in a testable manner in regard to direct manufacure of living organisms. Defined it so well that ID has been tested and falsified. In this discussion of origin of the universe, the "intelligent entity" has been defined sufficiently well to be testable if we could do the tests. But we are unable to do the tests. Look at it this way, if Ekpyrotic Theory is correct, it would falsify the theory that the universe was directly created by an intelligent entity. When has anyone demonstrated the existence of tachyons, strings, quantized space, or a number of entities science is/has worked with? That's the problem, iNow. You are using Special Pleading. What you are saying is that science is doing a "tremendous waste of time" on all these entities since the existence is questionable. On a more fundamental level, all scientific theories are proposed initially without demonstrating the existence first! In fact, that's why we propose entities, to test them to see if they exist! "I thought that scientific theories were not the digest of observations, but that they were inventions -- conjectures boldly put forward for trial, to be eliminated if they clashed with observations, with observations which were rarely accidental but as a rule undertaken with the definite intention of testing a theory by obtaining, if possible, a decisive refutation." Karl Popper, Conjectures and Refutations, 1963 p 38. If we make science work the way you say, then we have to stop doing science! It's a product of logic and there are many papers discussing what is called First Cause. Trace the chain of cause and effect back long enough and you must come eventually to an uncaused Cause that started it. See Hawking's A Brief History of Time. Often First Cause has been stated as an apologetic argument for the existence of God, but the objections have been to First Cause having to be God, not that there is a First Cause. BTW, I notice that you demand citations from me, but haven't provided citations when I asked for them. You aren't consistent with yourself, are you? See first statement of your post. Yes, you are arguing nonexistence -- "dismissing its existence". And I showed how this is a strawman and Special Pleading. And intelligent entity creating the universe answers the question "what's the origin of the universe?" That we now have a new question "what's the origin of the intelligent entity?" doesn't change that we have an answer. Let's take this out of deity and look at ekpyrotic theory. This theory states that our universe was caused by the collision of two 4 D 'branes in a 5 D space. Where did the 5 D space come from? Ekpyrotic doesn't answer that. By your criteria, we must dismiss ekpyrotic becuase it "displaces" the questions. I'm saying your criteria are wrong. I want you to provide peer-reviewed scientific papers that deity itself is human created. Wiki is not a peer-reviewed scientific paper. You are also confusing "shared belief" with scientific evidence. Yes, you and I share a belief that Zeus doesn't exist, but where is the scientific paper that does so? No, that isn't what you are claiming. Humans created the idea of entropy, atoms, forces, etc. You are claiming that the idea of deity has no basis in objective reality. That's what you need the peer-reviewed scientific papers for. Your claim was that there was "no evidence". That claim is false. Evidence outside science is indeed evidence. It's not scientific evidence. But science deals only with a small subset of evidence -- intersubjective. OK, first state why you reject the second. Then we can look at how you arrived at that conclusion. Of course, I never stated that "the sun and the stars and clouds are evidence of a creator." I only stated that the existence of the universe and the order it has provides the basis of the hypothesis that the universe was directly created by an intelligent entity. First, I never said evidence wasn't evidence if it wasn't scientific. That's your standard. I simply asked you to post the peer-reviewed scientific articles backing your claim that deity is only human created and not objectively real. You couldn't do that. You are now trying to cover the lapse. You responded that theists have decided that some versions of deity are wrong. So, you have to ask yourself: how did they do that? and why didn't they conclude that ALL versions of deity were wrong? As I've said before, science limits itself to only a subset of evidence. When you say "there is no evidence" you aren't limiting yourself to that subset. You are stating that in the broader set of evidence, there is none. We also have two separate issues here. 1. It is a scientific hypothesis that an intelligent entity directly created the universe and chose its order. As Popper noted (above), you don't need evidence to propose a scientific hypothesis. 2. Is there evidence for the existence of deity (intelligent entity)? Yes. There is evidence. The evidence theists have for the existence of deity is outside science because it is not intersubjective. The inspiration for a hypothesis/theory can come from anywhere. Gould says he was partly inspired by Marxism to propose punctuated equilibrium. Darwin was inspired by Malthusian economics to hypothesize natural selection. I personally know one scientist that was inspired by a hypothetical invasion of aliens to hypothesize why removal of neuraminic acids from glycoproteins would route them to lysosomes. Now, we know that Marxism is a failed system, but that doesn't mean PE is wrong. There is no evidence of an alien invasion, but it turns out the hypothesis is correct. So, wherever the concept of deity came from -- inside or outside science -- the hypothesis of direct action by deity in getting the universe to begin with becomes a scientific hypothesis. It's one, like ekpyrotic or No Boundary, that we can't test right now. But inability to test doesn't remove the hypothesis from science. I've walked you thru the "how". Go back and reread my post. If you have a specific question about a part of the argument you don't understand, then you can ask it. But there is no need to repeat all the arguments again unless and until you have a specific question. We don't know strings and quantized space exists. We don't know that a universe before this one existed. Bojowald's Loop Quantum Cosmology can't be tested. Neither can Hawking's No Boundary. "species" is ill-defined, but that doesn't stop us from using the concept. As Popper noted, nearly all scientific theories are based "purely on conjecture" to start with, and, in this case, the hypothesis is not "untestable by definition". I already noted one test that would falsify that the universe was directy created by an intelligent entity: the gravity waves associated with ekpyrotic theory. Talk about apples and oranges! We aren't talking about "the volume of a container on your desk"! We are talking invisble strings and imaginary time. What's the mass of a string? You either don't know what those theories are or are trying to blow smoke. Loop Quantum Gravity isn't about gravity, it's about space coming in small, quantized pieces. Since when has that been demonstrated? String theory doesn't talk about atomic interaction, but rather about all matter/energy consisting of strings and 'branes. Since when have they been demonstrated? Both of those theories lie in the "Possible" column, along with tachyons and an intelligent entity directly causing the universe. Find me a test of No Boundary. Find me a test of tachyons. Sorry, iNow, the "hard evidence and real world scientific tests" don't exist. We aren't doing religious discussion. We are talking about a scientific hypothesis that has not been falsified. And we are talking about religious arguments against deities that warp and misuse science. -
Eternal life and its effects on the human brain?
lucaspa replied to CurvKyle's topic in Other Sciences
But if we are going to keep the rest of the body going for that long, it means we have solved the problem of getting adult stem cells to replace aging cells. So we would be stimulating neural stem cells to make new neocortical neurons. I think Insane_Alien may have stated the biggest problem: memory storage. Either we would have to implant electronic memory with a bio-implant interface or find a way to cull memories. I think Poul Anderson mentioned this in one of his books, but I can't remember the name of it. Obviously, if the memory culler were misused, you could lose a lot of your personality as well. Merged post follows: Consecutive posts merged But finite. There does appear to be an upper limit: http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1234667 http://jcs.biologists.org/cgi/content/figsonly/120/21/3830 -
This gets very complicated. First, supposedly each gene codes for one protein. And the human genome has about 30,000 genes. But not all genes are expressed (turned on) in every cell. For instance, the dystrophin gene is only expressed in skeletal muscle cells. Albumin is only expressed in liver cells. Osteocalcin is only expressed in bone forming cells. So, each cell does "inherit" all the genes but does express them all. Depending on what cell type it is -- "phenotype" -- it expresses a subset of genes particular to that phenotype. Plus, many genes are expressed only in embryonic development. However, each cell expresses probably 20,000 genes. Many of them are common to each other, like the genes to break down sugar and get energy. Second, what we call "traits" are often the result of more than one gene. So, being "tall" is the result of many genes in many different cells, but particularly the genes in the growth plates in bones while you are growing up. That a trait is the sum of many genes is called "polygenic". Also, many genes participate in more than one trait. This is called "pleiotrophic". Third, many traits are also influenced by DNA that doesn't code for proteins. Some of this DNA is in the region that controls whether the gene is expressed or not. During embryonic development, this region is very important because how tall we are, for instance, partly depends on how long the IGF gene is turned on. Some DNA makes RNA, which in turn controls when genes are turned on or off. A recent article in Scientific American says that a major difference between humans and chimps is the HAR1 region. It encodes for an RNA but it appears to control the development of the brain -- particularly how wrinkled the surface of the brain is. So, bottom line: each cell expresses probably about 20,000 proteins but those proteins vary a bit depending on what the cell is. But "traits" are a bit different and I don't think anyone has numbered the "traits" in a human being.
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Is there a scientific case for an Intelligent Designer?
lucaspa replied to Alan McDougall's topic in Speculations
Nice duck, but you know that wasn't what I was referring to. Please try to be more honest about the points being made. You know I was referring to your criteria that you can dismiss an intelligent entity as creator of the universe because we don't know the origin of the intelligent entity. That criteria is invalid science. You don't have any interest in backing up your serious claim that humans invented deity? Wow! The topic is proper science. You don't want to treat that seriously? Then why are you in a science forum? As you well know, I'm not an IDer. ID is different from the hypothesis that the universe itself and the order of the universe was the direct action of an intelligent entity. ID is the hypothesis that specific entities within the universe -- particularly living things -- are directly manufactured by an intelligent entity. To emphasize what I stated before: I don't care what your personal beliefs are. It would appear that you are atheist. Fine. What concerns me are particular arguments you are using against deity. Those arguments are bad science. If we took those arguments seriously, then science would have to stop. -
Wow! That is high!. MB, the temperature of the sun is only 63 degrees K! So we have temperatures much, much lower than the Plank temperature. I suppose what MB meant was absolute zero. But as you noted, we have already gotten matter down to within a degree of absolute zero and it hasn't disappeared. Yeah, we need some sources. This is contrary to everything I've read on the subject. My reading doesn't extend to archXive.org, but I do try to keep up with the major discoveries in physics that are printed in Science and Nature and I haven't seen anything like this.
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What you need to do is look at "randomness" from the pov of an evolutionary biologist. You are tying yourself into knots because you are using the term differently than Gould uses it. In evolutionary biology, randomness means "random with respect to the needs of the population or the individual. In a climate getting warmer, just as many deer will be born with longer fur as shorter fur. Selection is nonrandom, and the shorter furred deer will do better and be selected. Gould was also talking about contingency in evolution. There are usually several different designs that will do the job. For instance, each species that uses oxidation for energy has its own cytochrome c protein that is essential in getting energy. By "own" I mean a cytochrome c that has a different amino acid sequence. Yet they all work equally well. So, why 4 limbs instead of 6 in vertebrates. Contingency. The variation for 4 limbs appeared first in vertebrates. Why did intelligence evolve in mammals instead of dinosaurs? Contingency. An asteroid hit earth 65 million years ago and wiped out the dinos. If it had not, sapience might well have evolved in small theropod pack hunters like the raptors. Gould is saying that, if the history of life on the planet were repeated, our particular physical form-- that of a modified ape -- would not have appeared. Sapience would probably eventually appear as natural selection explored possible genomes, but our particular genome would not have happened. In terms of randomness, from what I have read individual events on the quantum level are random. In large groups they are regular, but not the individual events. For instance, with 1,000 atoms of C14, 500 of them will decay in 5,280 years (a half-life). But which atoms will decay is "random". After all, all the C14 atoms are identical so why would 1 decay 1 second from now and the one adjacent to it not for 5,000 years? As an experiment for an engineer, you could hook up the controllers to a computer mouse to a liquid scintillation counter and place a solution containing C14 in the counter. The counter has photoelectric sensors at perpendicular to the axis of the vial and each other. So you could connect one to the vertical control to the mouse and the other to the horizontal control. The movement of the mouse would then be random.
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Is there a scientific case for an Intelligent Designer?
lucaspa replied to Alan McDougall's topic in Speculations
Irrelevant. All science does that. What caused the Big Bang? That's displacing the question of origin, isn't it? But does that invalidate that the Big Bang is the origin of our universe? NO! iNow, what you are doing is invalid science. You are trying to use an unanswered question on the next level to invalidate an answer on the level above. Whenever we answer a question, 3 or 4 new questions pop up out of the answer. That we don't know the answer to those questions has no effect on the answer. Question: Why does the universe exist? Possible answer: an intelligent entity created it. New question: what's the origin of the intelligent entity? IF it turns out our universe was created by an intelligent entity, then it will be time to ask the origin of the intelligent entity. If we take your criteria that we can dismiss an answer because we can't answer the next level, all science ceases. Merged post follows: Consecutive posts merged Aren't you equally mistaken to assume that the intelligent entity had a cause? Sauce for the goose. That is the correct answer to "what is the origin of the intelligent entity?" iNow, if it turns out that Logical and Mathematical Necessity caused the universe to exist, that is just as much a dead end as "God did it". Sometime we are going to get to an Uncaused Cause that started the chain of cause and effect. Whether that is deity, Logical and Mathematical Necessity, quantum fluctuation, etc, is immaterial. Your objections apply to each of them, but you are only using them as arguments against deity. That's Special Pleading Merged post follows: Consecutive posts merged Your evidence, please? And since this is the science forums, the peer-reviewed articles. Ah, Logical Positivism rears its ugly head again. As it happens, theists do have evidence of existence. That evidence comes from outside science. It is evidence you don't think is valid. This isn't about convincing you it is valid, but showing you that theists are basing their reasoning on evidence. In contrast, you are basing your reasoning on denial of evidence. For your personal beliefs, I don't care. But in trying to make your denial "scientific", you are attempting to change what science is and how it works. That I care about. So we should drop all work in String Theory, Loop Quantum Gravity, Loop Quantum Cosmology, No Boundary, etc? That's the inevitable conclusion from your criteria. All of these are based on entities that haven't been demonstrated to exist. So all is worthless speculation, according to you. This is one way you end up warping and harming science. -
Well. So you admit that your Opening Post statement that the data was only from 12 billion years ago is wrong. A backhanded way of admitting it, but an admission nonetheless. We have data from much more recent (in cosmological time) than 12 billion years. In fact, according to you, we have data from as recently as 0.00016 the age of the universe! Do you really expect something universal to appear so recently? You are denigrating inference. We do inference all the time. For instance, Agassiz looked at the marks of rocks in Europe and inferred that those marks were caused by glaciers. "Inference" is another way of saying: "the inference is the hypothesis that has survived all the attempts to show it wrong". Science is the business of inferring. Excuse me, but the Opening Post said: "If for example the universe began collapsing towards us at the speed of light then we would have no prior warning of this." That would be "contracting", unless you have some hypothesis about all the matter moving only towards us. You said "I did read that the expansion will continue until the average temperature of matter comes within one planck degree of absolute zero, at which time the matter will dissappear" If you meant "matter will disappear from view", then you should have said so. There's no need to get agressive with me when the problem lies with you being unclear. As it happens, because it is space that is expanding, objects the farthest away from us are indeed receding faster than lightspeed and are no longer visible to us. But to say "disappearing" by itself means that the matter no longer exists, not just that we can't see it. Strictly speaking, science cannot "prove". Science can disprove using deductive logic, but it can't "prove". So a characteristic of science is that it is tentative. We base our conclusions on the data we have now with the understanding that, if and when we get different data, we will change the conclusions. This happened in cosmology within the last 10 years. The inference was that Einstein's cosmological constant = 0 and that the ultimate fate of the universe depended on whether there was enough matter in the universe to halt the expansion begun at the Big Bang thru gravity. New data made us change our minds. If you want us to change our minds, then present us with some data, not rhetorical arguments. See above. What it means is "based on the data we have now, this is the only valid conclusion. If there is new data that contradicts the conclusion, then the conclusion changes." What you stated in the Opening Post was: "Suppose we establish contact with a nearby alien society and send them some everyday objects from earth among which is an elastic band. So they play with this and slowly stretch it taking readings of length, after a while they get bored, look at the data and decide that this elastic band could be stretched forever but they don't have the time to put this to the test so they mark rubber as infinitely strechable. What the hell has this got to do with the size of the universe I hear you ask well not a lot except that we seem to be applying this form of logic to where we think the universe is going." I was pointing out that your analogy and logic were wrong because the aliens would not do what you state. Very soon they are going to get to the breaking point with the rubber band. What's more, as they take readings of stress as well as strain (how far the rubber band stretches), the data is going to indicate that the rubber band has an ultimate breaking point. The only known force that would counter the expansion of the universe is gravity -- a universal attractive force. The data shows that there is a counter universal repulsive force (dark energy) that is stronger than gravity forcing the expansion of the universe. Now, you can be unhappy with the expansion and say "we don't absolutely know it will go on forever." However, with all we know now, the only valid conclusion is that the expansion will continue forever. You are speculating and placing bets on data that doesn't exist. You can personally do that, but it isn't science.
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waters relationship to life
lucaspa replied to wade.daniel.w's topic in Evolution, Morphology and Exobiology
The factory would not. That would be separate from the individual robot and the factory would not have the sapient features you are attributing to the robot. It would be an automated assembly line. It's that "shrinkage" that would be the problem. Remember, the robot is refined metal, plastics, doped semiconductor chips, etc. It's extremely unlikely that you are going to get a steel mill and oil refinery contained within the robot. I think you are confusing natural selection with evolution. It's a common confusion. Evolution is "descent with modification". This is not so much an "environmental process" as a process that will happen when the following conditions are met: " Many kinds of systems are evolutionary ... In all such systems there are populations, or groups, of entities; there is variation in one or more characteristics among the members of the population; there is HEREDITARY SIMILARITY between parent and offspring entities; and over the course of generations there may be changes in the proportions of individuals with different characteristics within populations. " Douglas Futuyma, Evolutionary Biology, (1999) pg 4. Robotic life would have to satisfy the conditions to undergo evolution.