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lucaspa

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  1. Natural selection is by far the overwhelmingly predominant mechanism for changing allele frequency. Of course, you did note the objections to equating change in allele frequency to evolution, didn't you? Changing allele frequency is part of evolution, but evolution is a lot more than just changing allele frequency. The other "major" way to change the frequency of alleles in population is chance. But, as you know from the equations, unless the population size is very small, chance alone has very poor odds of fixing an allele in a population and it works very slowly, taking millions of generations to either fix or eliminate an allele from a population. This is what allows population geneticists to determine whether changes in a population are due to genetic drift (chance) or natural selection. I mean just what everyone else means by designs: "to devise for a specific function or end". Notice that you have "designed ... by natural selection". The presumption with ID is that "design" always has the attached prepositional phrase "by an intelligent entity". Thus, their argument is that if you see something that has a specific function or end, then it was manufactured (designed) by an intelligent entity. Darwin's genius was in discovering an unintelligent process that also "devised for a specific function or end". Darwin agreed with Paley that living organisms exhibit traits that have a specific function or end. He just found another means -- a "secondary cause" -- to make them. Natural selection is an algorithm for producing designs: follow the steps and design is guaranteed. You can find this whole argument done in much greater detail in Daniel Dennett's Darwin's Dangerous Idea. Evolutionists have been tiptoeing around the issue of "design" for a long time. Dawkins used the term "designoid". I simply agree with Dennett that we ought to face the problem head-on. Let's challenge that hidden prepositional phrase used by creationists "by an intelligent entity" and realize that designs can arise by sources other than an intelligent entity. Please provide the equations and examples to show this. Hardy-Weinberg states (and shows mathematically) that, in populations meeting certain characteristics, allele frequencies are constant. Futuyma discusses this on pages 236-263 of Evolutionary Biology. He starts off by stating: "The Hardy-Weinberg principle is the foundation on which almost all of the theory of population genetics of sexually reproducing organisms -- which is to say, most of the genetic theory of evolution, rests. Its importance cannot be overemphasized. We will encounter it repeatedly in the theory of natural selection and other causes of evolution." "An important consequence of the Hardy-Weinberg principle is that no matter what the past history of a population may have been, a single generation of random mating yields the Hardy-Weinberg genotype frequencies." After one generation of random mating, gene frequencies will be p^2:2pq:q^2. Now, Hardy-Weinberg has several assumptions. 1. Mating is random. So sexual selection will skew that. (However, several studies have shown that sexual selection is a subset of natural selection, since selection is based on fitness characteristics of the mates.) 2. The population is very large. So, if there is a finite population, pure random chance could alter the gene freqencies in the next generation. This is random genetic drift. 3. Genes are not added from outside the population. Immigrants may carry different gene frequencies, and this is gene flow or migration. 4. Genes do not change from one allelic state to another. Such alteration is termed mutation. 5. All individuals have equal probability of survival and of reproduction. Natural selection upsets this. So, Futuyma concludes (with italics): "Inasmuch as nonrandom mating, chance, gene flow, mutation, and selection can alter the frequencies of alleles and genotypes,these are the major factors of evolutionary change within populations." pg 237 Now, Evolutionary Biology is the major textbook for college level evolutionary biology courses. If you want to argue with a textbook, you are going to have to provide considerable amounts of data to do so -- since the textbook already contains considerable amounts of data to back it. Terminology is NOT "entirely" arbitrary. It is related to observations. I submit that your definition of "slightly" is different from the standard usage. I can't see a reason to alter the terminology. The problem is that your alterations lead to confusion and are unnecessary. Yes, there is, because the generic term we are talking about is reproductive isolation. What are the processes that result in reproductive isolation? Allopatry -- geographical isolation -- is one of them. As you note, there are others. So calling ALL of them "allopatry" simply confuses the issue. If you want to talk about the generic topic, then say "reproductive isolation" Mayr's classification is the different ways that reproductive isolation can occur. DUH. So he is describing the processes that result in reproductive isolation. You are trying to substitute "allopatry" for "reproductive isolation". Again, since we already have a perfectly good term -- reproductive isolation -- your substitution only leads to confusion. If you mean "reproductive isolation" -- and you do -- just say so.
  2. I stand corrected. It's such a minor challenge. I had to read the article 3 times (twice deliberately looking for it) before I found it. Coyne should have made it his central thesis. It's so easy to overlook after the much lengthier paragraph before it: "What's annoying about Coulter (note: there's more than one thing!) is that she insistently demands evidence for evolution (none of which she'll ever accept), but requires not a shred of evidence for her "alternative hypothesis." She repeatedly assures us that God exists (not just any God -- the Christian God), that there is only one God (she's no Hindu, folks), that we are made in the image of said God, that the Christian Bible, like Antonin Scalia's Constitution, "is not a 'living' document" (that is, not susceptible to changing interpretation; so does she think that Genesis is literally true?), and that God just might have used evolution as part of His plan. What makes her so sure about all this? And how does she know that the Supreme Being, even if It exists, goes by the name of Yahweh, rather than Allah, Wotan, Zeus, or Mabel? If Coulter just knows these things by faith alone, she should say so, and then tell us why she's so sure that what Parsees or Zunis just know is wrong. I, for one, am not prepared to believe that Ann Coulter is made in God's image without seeing some proof." Now, you can look on this as Coulter's inconsistency. However, any theist is going to look on this as the standard atheist attack against theism. Right here Coyne turns this into an atheism vs theism fight: theism has no evidence and is therefore not valid. So, after delivering such a viscious attack against theism (and particularly Christianity), are we really supposed to take Coyne's weak paragraph of 1/3 of scientists being theists seriously?
  3. Of course it is: a refuted (or falsified) theory. Being falsified doesn't remove a theory from science. It just moves it from the short column of currently valid theories to the very long column of falsified theories. However, from 1700 to 1830 creationism was the accepted scientific theory. The reason we have this confusion that creationism is not science is because of lawyers. When creationists wanted YEC taught in public school science classes, the ACLU lawyers decided that their argument would be that creationism is not science. They then got Michael Ruse to mistakenly define science such that creationism would be excluded. So, instead of a definition of science and scientific theories done by scientists or philosophers of science, we got one made up by lawyers. In the process, we lost the most potent argument against creationism. Saying "creationism is not a scientific theory" says nothing about its truth value. There are lots of statements/ideas that are not scientific theories but which we accept/know are true. By putting creationism outside science, we were unable to pronounce on whether it is true. However, if we evaluate creationism like we do any other scientific theory, then we can pronounce will absolute confidence that it is wrong. (And still keep it out of science class becaus the proponents don't want it taught as wrong, but as valid.) "There is another way to be a Creationist. One might offer Creationism as a scientific theory: Life did not evolve over millions of years, rather all forms were created at one time by a particular Creator. Although pure versions of Creationism were no longer in vogue among scientists by the end of the eighteenth century, they had flourished earlier (in the writings of Thomas Burnet, William Whiston, and others). Moerover, *variants* of Creationism were supported by a number of eminent nineteetn-century scientists -- William Buckland, Adam Sedgwick, and Louis Agassiz, for example. These Creationists trusted that their theories would accord with the Bible, interpreted in what they saw as a correct way. HOWEVER, THAT FACT DOES NOT AFFECT THE SCIENTIFC STATUS OF THOSE THEORIES. EVEN POSTULATING AN UNOBSERVED CREATOR NEED BE NO MORE UNSCIENTIFIC THAN POSTULATING UNOBSERVABLE PARTICLES. [emphasis mine] What matters is the character of the proposals and the ways in which they are articulated and defended. The great scientific Creationists of the eighteenth and nineteenth centuries offered problem-solving strategies for many of the questions addressed by evolutionary theory. They struggled hard to explain the observed distribution of fossils. Sedgwick, Buckland, and others practiced genuine science. They stuck their necks out and volunteered information about catastrophes that they invoked to explain biological and geological findings. Because their theories offered definite proposals, those theories were refutable. Indeed, the theories actually achieved refutation." Philip Kitcher, Abusing Science, the Case against Creationism, 1982, page 125.
  4. I've seen several papers that refute the idea of neutral speciation. Instead, reproductive isolation is the result of natural selection for reproductive isolation, not chance. 1. M Nei and J Zhang, Evolution: molecular origin of species. Science 282: 1428-1429, Nov. 20, 1998. Primary article is: CT Ting, SC Tsaur, ML We, and CE Wu, A rapidly evolving homeobox at the site of a hybrid sterility gene. Science 282: 1501-1504, Nov. 20, 1998. As the title implies, has found the genes that actually change during reproductive isolation. 5. Rice, W. R. 1985. Disruptive selection on habitat preference and the evolution of reproductive isolation: an exploratory experiment. Evolution. 39:645-646. 6. Ringo, J., D. Wood, R. Rockwell, and H. Dowse. 1989. An experiment testing two hypotheses of speciation. The American Naturalist. 126:642-661. 7. Schluter, D. and L. M. Nagel. 1995. Parallel speciation by natural selection. American Naturalist. 146:292-301. 1. G Kilias, SN Alahiotis, and M Pelecanos. A multifactorial genetic investigation of speciation theory using drosophila melanogaster Evolution 34:730-737, 1980. 3. KF Koopman, Natural selection for reproductive isolation between Drosophila pseudobscura and Drosophila persimilis. Evolution 4: 135-148, 1950. 1. Speciation in action Science 72:700-701, 1996 However, the argument is first based on the hypothesis that venom itself is advantageous. And this, in turn, is a posteriori. It's established empirically that the cost of producing venom is offset by the benefits of venom killing the prey. Once you have venom as advantageous by post hoc analysis, then you can make the a priori argument about more potent venom. Also, there can be a cost in manufacturing or obtaining the amino acids. Thus, changing one amino acid for another is not necessarily neutral. Eventually, there is not going to be any selection pressure for more potent venom. After the venom reaches a point where it kills the prey reliably quickly enough that the prey doesn't get away, then any increases on this would not be selective (in and of itself). This more potent venom would be selectively neutral. However, note that if more potent venom is linked to an increase in the size of the snake, then the more potent venom kills larger animals and again confers a selective advantage.
  5. Please expand on this statement. What do you mean by "drives evolutoin"? There are the hyperselectionists -- such as Dawkins -- that make the statement that natural selection accounts for all traits in all species. The pluralists -- such as Gould and Lewontin -- argued against this. Some traits are not direct products of natural selection -- such as male nipples and the spurs on the ankle bones in pandas. Everyone agrees that natural selection is the only process that gives you the designsin organisms. Not a good idea to invent your own definitions in science. Especially when you are discussing with non-scientists. "Allopatry The condition of two populations of the same species being separated by a geographic barrier that prevents them from interbreeding." http://www.cartage.org.lb/en/themes/Reference/dictionary/Biologie/A/354.html Allopatry is specifically associated with geographical isolation. As you noted, you can have restrictions on interbreeding among populations in the same geographic area. In fact, Mayr lists the types of processes that result in reproductive isolation. However, each of these has different terms (such as ethnological isolation), so using "allopatry" in the general sense you do is actually confusing. "Classification of Isolating Mechanisms 1. Premating or prezygotic mechanisms: Mechanisms that prevent interspecific matings. (a) Potential mates are prevented from meeting (seasonal and habitat isolation) (b) Behavioral incompatibilities prevent mating (ethological isolation) © Copulation attempted but no transfer of sperm takes place (mechanical isolation) 2. Postmating or postzygotic mechanisms: Mechanisms that reduce full success of interspecific crosses (a) Sperm transfer takes place but egg not fertilized (gametic incompatibility) (b) Egg fertilized but zygote dies (zygotic mortality) © Zygote develops into an F1 hybrid of reduced viability (hybrid viability) (d) F1 hybrid is fully viable but partially or completely sterile, or produces deficient F2 (hybrid sterility)" Ernst Mayr, What Evolution Is pg 171
  6. No, we don't. In particular several very prominent evolutionary biologists do not agree that "change in allele frequency" is evolution. It is incomplete. " 'Evolution' implies change with continuity, usually with a directional component. Biological evolution is best defined as change in the diversity and adaptation of populations of organisms." pg. 47 "No Darwinian I know questions the fact that the processes of organic evolution are consistent with the laws of the physical sciences, but it makes no sense to say that biological evolution has been "reduced" to physical laws. Biological evolution is the result of specific processes that impinge on specific systems, the explanation of which is meaningful only at the level of complexity of those processes and those systems. And the classical theory of evolution has not been reduced to a "molecular theory of evolution," an assertion based on such reductionist definitions of evolution as "a change in gene frequencies in natural populations." This reductionist definition omits the crucial aspects of evolution: changes in diversity and adaptation. (Once I gave a lump of sugar to a racoon in a zoo. He ran with it to his water basin and washed it vigorously until there was nothing left of it. No complex system should be taken apart to the extent that nothing of significance is left.)" Ernst Mayr, Evolution, Scientific American 239: 47-55, Sept. 1978. A complete definition of evolution is given by Futuyma in Evolutionary Biology: "Thus, evolution, in a broad sense is descent with modification, and often with diversification. 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. This process consitutes descent with modification. Populations may become subdivided so that several populations are derived from a COMMON ANCESTRAL POPULATION. If different changes in the proportions of variant individuals transpire in te several populations,the populations DIVERGE, OR DIVERSIFY. ... All these properties of an evolutionary process pertain to populations of organisms, in which there is hereditary transmission of characteristics (based on genes, composed of DNA or, in a few cases, RNA), variation owing to mutation, and sorting of variation by several kinds of processes. Chief among these sorting processes are CHANCE (random variation in the survival or reproduction of different variants), and natural selection (consistent, nonrandom differences among variants in their rates of survival or reproduction). It is natural selection that causes adaptation -- improvement in function. Thus biological (or organic) evolution is change in the properties of populations of organisms , or groups of such populations, over the course of generations. ... Biological evolution may be slight or substantial; it embraces everything from slight changes in the proportions of different forms of a gene within a population, such as the alleles that determine the different human blood types, to the alterations that led from the earliest organisms to dinosaurs, bees, snapdragons, and humans." Douglas Futuyma, Evolutionary Biology, (1999) pg 4. [emphasis in original]
  7. I fail to see what H-W has to do with it. Are you suggesting, perhaps, that as all alleles at a locus are not in H-W equilibrium, selection must have occurred? 1. You need to go back and tell us why you need a definition of "useful" that doesn't entail the defintion of "do better". What we have from Darwin is " But if variations useful to any organic being do occur, assuredly individuals thus characterized will have the best chance of being preserved in the struggle for life;" From Merriam-Webster: "1 : capable of being put to use; especially : serviceable for an end or purpose <useful tools> 2 : of a valuable or productive kind " Now, where is "do better"? 2. Hardy-Weinberg gives you a starting point to determine what will happen if there is NOTHING acting on the population. That give us an objective place to determine if something is happening to the population. As you implied, the effect does not have to be natural selection. It can be genetic drift. BUT, there are mathematical tests to distinguish between the two. So, instead of having a judgement call of "do better", H-D serves as the objective scorekeeper. Once we identify alleles/traits that are increasing, eliminate genetic drift as the cause, then we can use reverse engineering to determine why they are doing better. You still haven't provided a source for how your "colleagues" use the term. If they truly do, then they have written it down somewhere. All I'm asking you is to provide a source. Instead, you keep telling me to take your word for it. But that is the issue: are you stating the principle correctly. To decide that, we can't take your word. [ quote]x is not true in general means that x is not always true. x not-true = x false. If x is not always true, then x not-true is NOT = x false. For instance, to say "the statement 'the earth is flat' is false" is not to say " 'the earth is flat' is not always true" Because that implies that the earth can sometimes be flat. Nope. Because 'x is true' is not the same statement as 'x is true in general'. You have added the phrase "in general" and, thus, changed the statement.
  8. Just what I said! Therefore they are not the courts pronouncing, but the majority stating their belief. Remember the claims! Your original claim was that the court decisions obtained by atheists were equivalent to the Pledge and the actions of judges (in their personal lives) wanting the 10 Commandments displayed in courtrooms or on their judicial robes. Try to remember that we are not discussing whether the prejudice against atheists is correct or rational, just WHY there is such prejudice. Whether those reasons are ethical or rational is a separate issue. I know what the 1st Amendment states. But it does matter what the majority thinks when we are trying to find the reasons for prejudice or resentment of court decisions. Let's take this out of the theism vs atheism discussion for a minute and look at 2 other recent Supreme Court decisions. One is Bush v Gore in 2000 that stopped the Florida recount. You weren't angered by that? Didn't you feel that your beliefs in justice, accurate elections, and the choice of the American people was violated by the Supreme Court? I was and many other people were also. Or take the recent decision regarding eminent domain. That private property could be taken by the state so that private developers could put up shopping malls, etc. that would then profit the developers. By far the majority thought that decision was not right, even tho the Supreme Court said it was constitutional! The fact you have to come to grips with is that some theists feel the same way about Supreme Court decisions removing organized prayer from public schools, trying to remove "under God" from the Pledge, etc. Yes, it is justified by the Constitution, but they still feel it is wrong. Therefore there is resentment because they feel the courts are forcing -- in their opinion -- theism out and atheism in. Also remember that, in other cases where people thought the Constitution was wrong, the Constitution was amended! The Constitution had slavery as legal and kept women from voting. Both changed by amendments. So, if enough Americans feel that the attempt to remove theism in general is wrong, they will eventually ammend the Constitution and then you won't even have the argument of unconstitutionality. Atheists must convince theists that they should keep the Establishment Clause and that atheists should be protected by it against the establishment of generic theism as a religion. If they continue to alienate the vast majority, then the protection will be removed. I emphatically think such a removal would be very wrong. Which makes my emphasis more on 1) why theists would see such a removal as a "good" thing and 2) the tactics that would convince theists that atheism deserves protection by the Establishment Clause. I disagree. Altho I think that, right now, you should be happy the Supreme Court is not judging the constitutionality. You could easily get a judgement you don't like (and that I would regard as wrong). As I said, since we have a lag in the perception of atheism as a rational faith, the judges could decide that "under God" is permissable as long as you don't say WHICH god. Display of the 10 Commandments would be out as they specify a particular god. [qutoe]Atheism is simply a lack of belief in god(s). It is not a faith or religion. It is not a belief system. The about.com definition is flawed and is selective data. It is designed to hide that atheism is a faith. Which is what I was talking about as one of the reasons for the prejudice against atheists: many dishonestly try to deny atheism is a faith. "Atheism (Greek a, "not"; theos, "god"), doctrine that denies the existence of deity. Atheism differs distinctly from agnosticism, the doctrine that the existence of deity can be neither proved nor disproved. Many people have incorrectly been called atheists merely because they rejected some popular belief in divinity.1" 1"Atheism," Microsoft® Encarta® 96 Encyclopedia. © 1993-1995 Microsoft Corporation. All rights reserved. © Funk & Wagnalls Corporation. All rights reserved. "Atheism«AY thee ihz uhm», is the belief that there is no God. Atheism is the opposite of theism, the belief that God exists." Ivan Soll, "Atheism," World Book Online Americas Edition, http://www.aolsvc.worldbook.aol.com/wbol/wbPage/na/ar/co/035360,November 4, 2001. http://www.positiveatheism.org/faq/faq1111.htm#WHATISPOSATH "since no gods exist" http://www.atheists.org/Atheism/atheism.html "Atheism is based upon a materialist philosophy, which holds that nothing exists but natural phenomena. There are no supernatural forces or entities, nor can there be any." "Atheism -- the belief that there are no gods." Douglas A. Krueger, What Is Atheism? A Short Introductory Course, pg 19. What's worse, the about.com position is untenable. You can't simply have a "lack of belief" as atheism uses the term. In order to continue to be an atheist, you MUST make positive statements of faith. In particular, you must make the positive statement of faith that "natural" = "without God". That is part of the statement at the atheist.org site. "lack of belief" is semantically = to "believe the opposite". To say "I lack belief that deity exists" is the same as saying "I believe deity does not exist." The only reason to use "lack of belief" is to try to hide that atheism is a belief/faith. Think about this: one reason evolutionists have such dislike and prejudice against IDers is that they try to say their belief is not a belief. Same thing here. You ignored that, before 1858, atheism was not a rational faith. Therefore, the faith aspect was more clearly visible. Of course not. After all, you say atheism isn't saying that. If atheism is "lack of belief", then why would the government ever declare "Gopd does not exist"? You betrayed the true nature of atheism in these quotes. If your side is "God does not exist", then that is a positive faith, not simply "lack of belief"! It's defensive, not arrogant. Defensive because they are being forced by the courts to give up declarations that they think are true. They are not being given any rational arguments -- from within the premises of theism -- why they should take the statements out. Read what I wrote: "4. In their arrogance, atheists have failed to make use of the "do unto others ..." argument that would have helped theists understand the atheist position and given theists an argument within theism to agree with the atheist position." The arrogance comes from 2: "2. Atheists have generally not been sensitive to the feelings of theists on the matter. They have used force in the form of the courts instead of trying to engage theists in dialogue and explain their position. IOW, atheists have often been arrogant." The arrogance comes from 1. using the courts to enforce the atheist position instead of engaging in dialogue with theists and trying to convince them. So yes, atheists have displayed arrogance because they went directly to the courts instead of trying politics and trying to get people to agree voluntarily to their position and what constitutes "neutrality". From the position of your opponents, "under God" IS neutral, because it doesn't advance a particular religion. Instead of arrogantly using ONLY the courts, atheists should have tried using dialogue. 2. Failing to use a powerful argument that would appeal to theists because it comes from theism. The arrogance involved is in thinking that theism has no merit and deserves no respect, therefore using arguments from within theism is beneath atheists. 3. Failing to reach out to theists like myself that agree with them. Instead of finding common ground and listening, all theists are rejected because the arrogance says "we don't need you or your arguments". For the same reason there was a burden on abolitionists to do something to achieve a government where liberty was a right for everyone or for feminists to achieve a government where the right to vote applied to women. One problem you are facing is that theists have evidence for belief in the supernatural. Either their personal experience of deity or accounts of experience that the theists trusts is true. So you have a burden to show 1) that atheism is a rational position and 2) generic expressions of an entity for which theists have (personally) convincing evidence should not be stated in public. Now, if you insist that atheism is simply "lack of belief", then all you have done is say that you don't agree with theism. So what? The Pledge doesn't require you to AGREE that the US is "under God", anymore than it requires you to AGREE that the US is "one nation". You could be an unreconstructed Southerner that still thinks the South should be independent. The Southerner would have a "lack of belief" that the US should be one nation. The argument of proponents of organized school prayer would say that you are not required to recite a prayer. If you only have a "lack of belief", then other people saying a generic prayer doesn't establish any particular religion. Religion being, in your own argument, a particular version of theism. Theism in general would NOT be a religion, but rather an established "fact". As I think on this, ONLY if atheism is a faith would the Establishment Clause apply. Then the government would be attempting to establish a religion that is different from the faith ("religion") of atheism. But as long as it is maintained that atheism is simply "lack of belief", then as long as the government doesn't endorse a particular belief (religion), then it is fine. You could get the 10 Commandments from being displayed, but couldn't stop the hanging of pictures of Buddha, Jesus, and Vishnu in public schools (as long as it was all of them) or the organized generic prayer to deity. There would be no establishment of "religion". Yeah, as I think about this, as long as atheism is maintained as "lack of belief", then it has no standing in regard to the establishment of "religion". OTOH, if atheism is a positive belief (as it is), then any expression of theism, no matter how generic, would be a violation of the Establishment Clause.
  9. The evolutionary geneticist hadn't read chapter 3 of Origin of Species? You could be a bit more gracious in admitting that the idea was in error.
  10. The logical chain is still a syllogism. It's just that the syllogism has been confirmed by empirical observation. There are objective criteria that can be used to assess "do better". Since you don't want me to lecture you on evolutionary genetics, I will only remind you of Hardy-Weinberg. Yes, I do need a source. Because we have the situation x is not true in some situations. That is not the same as saying "x is not true". That statement has the implied "x is not true AT ALL" "false in general" is not the same as "sometimes may not be true. "in general" refers to a majority of the time. "sometimes" refers to much less than 50% of the time. So I also need as source that equates "in general" with "sometimes'. Thank you.
  11. Please tell me an assembly line that turns out hammers or screws with variations above the trivial molecular level. It can't be, because you see the organisms replicate and there is no intelligence in sight, is there? Creationists often try to say that some organisms -- horseshoe crabs, sharks, for instance -- are "unchanged" for tens of millions of years. However, this is untrue. Altho the basic shape is similar, the species of horseshoe crab that exists today is different than those in the past. Also, there are actually 3 forms of natural selection: 1. Directional. This is the one that is usually considered, and the one that changes a population as the environment changes. 2. Stabilizing selection. Once a population reaches a "fitness peak" and is well-adapted to the environment, further changes will actually make the individual LESS fit for that particular environment. So, as long as the environment remains constant, natural selection will actually act to prevent change to the population and instead narrow the variation to the optimum for that particular environment. 3. Disruptive selection. This happens when a population has wide geographical range and faces different environments in different parts of the range. There is a tendency for directional selection to adapt the sub-populatoins to the particular environments, but gene flow between populations counters that. If for any reason, there is a disruption of gene flow, you get separate species. This is what happens in "ring species". As we both noted, human manufacture does have minor variation: each hammer is not identical if you would analyze it in enough detail. There would be irregularities at the level of the atom between different hammers. Because of the second law of thermodynamics, complete replication is not possible. It's just that the differnces between hammers is too minor to matter. Also, because hammers don't replicate over generations, it is not possible to accumulate differences to turn a claw hammer to a sledge hammer. BUT, in living organisms you have an amplification mechanism -- development -- that turns the molecular variations at the DNA level to macro differences at the level of the organism. Also, differences accumulate because of natural selection. So the minor changes are additive, not isolated like they are in manufactured artifacts, and you can get the equivalent of turning a claw hammer into a sledge hammer. Manufactured artifacts are isolated. You make one hammer. Then you make another. But in biological organisms you have the equivalent of one hammer making another hammer. The hammers are connected by ancestor-descent.
  12. Actually, it's not the same street. What you had with the Pledge was the Congress inserting the words. As representatives of the majority -- theists. What you have with the actions of judges you mention are not their rulings from the bench, but expression of their personal beliefs. Which are then suppressed by rulings from the bench. Yes, they are when taken in historical context. Altho most of the Founding Fathers were Christians, they established a secular government. However, before 1858, atheism simply wasn't a rational faith. It was an irrational position and thus was safely ignored. Therefore we could have saying like "in God we trust" on our currency because it did not support a particular form of theism -- and thus is "secular". After 1858, atheism was a rational faith. But atheists didn't advocate for consideration of their beliefs under the First Amendment until Madeleine O'Hare in the 1960s. And then atheists didn't go thru the Executive or Legislative branches of the government. IOW, they didn't try to convince the majority of the population that atheism was a rational belief and that phrases like "in God we trust" represented an endorsement by government of the general religion of theism as opposed to the general religoin of atheism. Instead, they had the courts enforce their views. The key here is "enforce". They didn't "convince" or get consensus, but used force. Then you haven't met many Christians. The major opposition to teaching creationism in public schools has come from Christians. There are very few, or no, Fundamentalists that want a secular government. They actually want a theocracy. No. Applying "do unto others as you would have them do unto you", I as a Christian understand how theists have unintentionally but thoughtlessly endorsed a religion: theism. They didn't mean to, because they weren't thinking in terms of theism vs atheism, but instead of endorsing particular forms of theism (Christianity) over others. 1. We simply haven't caught up to the reality that atheism is a rational faith and, therefore, must be respected as such in the First Amendment. 2. Atheists have generally not been sensitive to the feelings of theists on the matter. They have used force in the form of the courts instead of trying to engage theists in dialogue and explain their position. IOW, atheists have often been arrogant. 3. Atheists have generally been reluctant to acknowledge, or resistant to the fact, that atheism is a faith. Therefore they have not availed themselves of the argument of protection under the Establishment Clause. Instead, the arguments have been an attack on theism as the "only" religion involved. 4. In their arrogance, atheists have failed to make use of the "do unto others ..." argument that would have helped theists understand the atheist position and given theists an argument within theism to agree with the atheist position. 5. There is the, IMO, minor problem that there are demagogues within theism that want to misrepresent the issue. However, IMO these demagogues could be marginalized if atheists would have pursued 2-4 more agressively. For instance, my parents have sometimes gotten upset with some of the removals. My father wondered why the 10 Commandments couldn't be displayed outside a courthouse. Certainly we could all agree on "Thou shalt not commit murder", "Thou shalt not steal" etc. as a basis for justice. And we can. But as soon as I pointed out the first 2 Commandments and the effect on Hindus, Native Americans, and atheists, then he immediately understood that those Commandments promoted a particular deity and religion and not rules for justice.
  13. I agree that theism and atheism is about belief. And that agnosticism is about knowledge. However, to do a bit of semantics, when you say that "the nature of God is fundamentally unknowable through logic or science" you are stating a belief. Agnosticism, as used originally by Huxley, was simply an "I don't know whether deity exists or not". Somewhere since, some people have tried to tack the idea that the existence of deity is unknowable. I don't see how you can speak for all the future of what science and logic can do. Based on what we know now, science does not know whether deity exists or not. But to extrapolate that to unknowable is also a form of belief. That is not tenable. Because theists do have rational discourse on the subject. Also, "don't believe" is logically not tenable. What you have to have are some positive beliefs in order to be atheistic. Semantically, I would dispute your use of the term "gnostic". According to Webster's "gnostic" has only one meaning: " an adherent of gnosticism" Gnosticism is a particular form of theism. Therefore to attempt to use "gnostic" as any description of atheism or of theism in general is semantically invalid. That second axis doesn't exist. It is semantically invalid because agnostic and gnostic don't mean what you are trying to use them for. Your atheism/theism axis includes the middle ground of agnosticism. What you are trying to do with the agnosticism/gnosticism axis is delineate the ways people justify atheism or theism. I submit that this isn't necessary the way you are doing it. The justification within the atheism/theism axis boils down to one thing: evidence. What people consider valid evidence and what evidence they personally have. Of couse it is absurd, because they are equating atheism with certainty when it is a belief. However, they do have a point because many atheists mistakenly ascribe certainty to atheism.
  14. True, but that isn't where the theists are looking. Instead, they are looking at the cases the atheists bring in court. The case to have a monument of the 10 Commandments removed from a courthouse, to remove the words "under God" from the Pledge, and to remove a cross from public land. The perceived attack by atheists doesn't come open in the media or public discourse, but thru the backdoor of the courts under the aegis of the First Amendment. Therefore the massive amount of public support for theism doesn't count. Theists perceive that their beliefs are being persecuted by the minority. He's not that lonely. Add Peter Atkins, PZ Meyer ("best" science blog according to Nature), William Provine, Daniel Dennett, EO Wilson, etc. All of these have launched very public (in the media) attacks on theism in the wake of the decision in the Dover PA trial on ID. PZ Meyer attacked Kenneth Miller, of all people, for even daring to suggest that science and religion can co-exist. I'll get the blog site for you. http://news.yahoo.com/s/usatoday/20060116/cm_usatoday/letsacceptthefaultlinebetweenfaithandscience http://www.boston.com/news/globe/ideas/articles/2006/01/29/supernatural_selection/
  15. There aren't enough atheists to have a war. Nor are they really associated with a nation-state. The greater danger, IMO, is that atheists would end up like the gypsies and Jews in Nazi Germany or Christians in the Soviet Union: subjected to extreme discrimination or killed. A war where one side can't fight back effectively is called a "massacre". However, if the Fundies have their way, IMO the atheists will be followed by the agnostics and then Christians.
  16. I think so. I'd say "monocyte" but it could easily be one of the granulocytes. The OPer said he got this from a sample of pus. So the thick part would be consistent with water combined with proteins/components left over from dead bacteria and cells. We don't know much more about the processing of the tissue, and I don't think the poster has access to stains, unfortunately.
  17. No. And the common usage wouldn't appy here anyway. What the authors are doing is retracing evolution on a molecular level. NOT doing evolution in reverse. The research is showing how things got to be the way there are today by means of evolution. In this case, there was gene duplication -- a well-known phenomenon where the mistake in copying DNA results in 2 copies of the same gene. Now, while the original copy continues to do the job, the second copy can change without any penalty to the animal. After all, the original job is still covered. In gene duplications known to date, the changes came in the coding region -- the areas that tell what the amino acid sequence of the protein is. The different types of collagen arose this way. However, in this case the amino acid sequence of the protein for Hox1 is the same. What changed was the regulatory sequence. Remember, proteins are not turned on all the time in all cells. The regulatory sequence tells when to turn on the gene and have it make the protein. It is part of the gene but the DNA sequence that is the regulatory sequence lies in front of the sequence for the protein. Here the regulatory sequence changed so that Hox1 is expressed at different times in different cells. Same protein doing 2 different things in the development of the central nervous system depending on which cells make it and when in development they make it. By making Hox1 later in development, it allows the new trait of facial expression.
  18. Thank you. Darwin also, in Chapter 3, documented many cases of the struggle for existence. The geometric increase is the cause of the struggle, but the struggle itself can be observed, often directly.
  19. Now you've made it important. By saying the minor premise -- struggle for existence -- is "assumed". It's demonstrated. Darwin spent an entire chapter on the "Struggle for Existence". http://pages.britishlibrary.net/charles.darwin/texts/origin_6th/origin6th_03.html What you are saying is "assumed" is that the "fittest survive". The problem there is that you are using the soundbite of natural selection to be all of natural selection. It's not. "Survival of the fittest" is the soundbite version. Like all soundbites, it is not totally accurate. What natural selection says is that variations useful to the organism will do better in the struggle for existence and those variations will be passed to the offspring. Over time, the accumulation of new variations will change a population and transform a population. Can you please find me a source for that "one says that x is false in general"? I've never come across that phrase in all my reading. Also please find a source that "not true in general" = "false". I've always seen "false" associated with being "totally wrong", not with "not true in general". Thank you.
  20. The general figure given is 10% agnostic + atheist, so 3% atheist fits within the range. As you said, I expect the prejudice to be strong among Fundamentalists, and they are 50% or so of Americans these days. However, in order to have these results, there must be a considerable amount of prejudice among mainline Christians. And that is surprising. I speculate that much of the prejudice arises because atheism has been pushing back traditional expressions of religion -- no organized school prayer, no display of the 10 Commandments, removal of a large picture of Jesus from my former grade school, etc. Therefore atheism is viewed as an agressor to theism. Couple this with the attitude of many atheists that atheism is not a faith and is epistemologically superior to theism and you have the appearance that it is atheism that is intolerant and seeks to destroy theism and theists. For the poster who wondered why atheists would be put lower than Muslims (who were mistakenly equated with terrorists), there is your answer. Atheism is perceived as just as intolerant as radical Islam and bent on the destruction of theists. Most Christians recognize that the claim of epistemological superiority is bogus, but don't know why and can't articulate an argument against it. This inability leads to frustration and might also contribute to the prejudice. Dak also has a point. Even Hinduism is moving toward monotheism. So it is only atheism that is outside the fold of "in God we trust". AzurePhoenix: "The conservative view towards atheists that I've noticed always seems to associate them with things like satanism, communism, anarchism and fascism. There's lots of misunderstanding in there." Remember that Fundamentalism is also an intolerant faith. Therefore they wish total hegemony for their faith (which isn't theism, BTW). Atheists for Fundies serve the same purpose as Jews for Nazism: a convenient bogeyman to rally against.
  21. I don't think the thick portion is the membrane. I think it is an artifact of the processing. I suspect it is the edges of the liquid in which the cell is suspended -- the rest has dried up. The cell membrane parallels the thick part just inside it.
  22. Depends on the mass of the sphere. There are equations to calculate that. I'm sure a google search would find them.
  23. lucaspa

    Animal Testing

    Your "challenge" consists of personal opinion -- what you decide to do for yourself. That's not the same as a universal, objective ethic. Is it ethical to kill young animals for food? Yes. Do you eat eggs? You say ethics by humans must not only apply to other humans but other species. However, you say that ethics does not apply to other species. That's where the logical disconnect comes in and what undermines your argument. Ethics need to be universal, otherwise you can't use them to tell us what we ought to do. If ethics are relative, and only apply where you want them to because this is what you want, then you have special pleading. Your argument is that it is unethical to kill living beings not only within your species but outside your species. However, that argument must apply to ALL species. So it is also unethical for wolves to kill. Uou are still working with human ethics -- what humans decide is ethical. You simply want to extend human ethics to other animals. That is a desire of yours, but it is not an ethical imperative or rule. The rest of us say we should treat animals humanely, but this is based on the idea that humans who wantonly mistreat animals are going to mistreat humans, also.
  24. A syllogism is a form of argument. Two premises and a conclusion. Darwin has those premises. You can find them in the "ifs": 1. Variation. 2. Struggle for existence (deriving from geometric increase in population) Conclusion: variations beneficial to the organism will be selected. It's not an "assumption" that the survivors are the fittest. Population genetics demonstrated that by looking at traits/designs and the environment. It was easy to reverse engineer the environment to show that the designs selected did work better in the environment. The peppered moth in England is one example. One recent study where the "fittest" were predicted ahead of time is here: Evaluation of the rate of evolution in natural populations of guppies (Poecilia reticulata). Reznick, DN, Shaw, FH, Rodd, FH, and Shaw, RG. Science 275:1934-1937, 1997. The lay article is Predatory-free guppies take an evolutionary leap forward, pg 1880. This is the idea that EVERY trait is under natural selection. It is also Dawkins' position. Gould, Lewontin, and others argued against it. I would agree that it is false, but that is my conclusion from the data. However, Dawkins and others have not reached the same conclusion and the argument continues. So I'm not at the point where I can say we "know to be false in general". I can point to examples and say "selection doesn't account for that particular trait" but I certainly can't say that "in general" traits that are in existence were not selected for.
  25. Human manufacture. We turn out hammers, screws, etc that are identical. The degree of how identical depends on the precision of the machine tools. You can quibble that there is variation at the molecular level, but at the level of "trait", each hammer or screw is identical.
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