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"Scientific" Evidence for Creation
lucaspa replied to MoMo's topic in Evolution, Morphology and Exobiology
There are 2 different claims about how close to the "source" the writings are: 1. The sacred writings are inspired and for theological purposes (2 Tim. 3:16 as an example) 2. The sacred writings are dictated word for word: Fundamentalism and Islam's claim for the Quran. If you go with 1, then the object is to look at the theological messages of sacred writings. In looking at Genesis, it can be seen that a literal reading of the different creation stories in Genesis 1 and Genesis 2 contradict. This is a huge neon sign that the stories are not there for a history, but for theology. And that is their purpose. The theological messages work just as well in modern science as they do in the Babylonian science in which they are set. "in our image" in Genesis has been misunderstood to mean a physical image. And, the Judeo-Christian deity is very carefully separated from ANY physical form. So any sentient beings, of course, would not "look" like Yahweh, anymore than we look like Yahweh -- because Yahweh has no form to look like. You need to be more specific here. I would say that scientific theories based on a literal reading of sacred writings have been disproved. So what? Lots of scientific theories have been disproved. But I do not know of any scientific work that disproves the basic theology of the 3 main monotheisms today. Perhaps you could cite the papers. 1. The philosophy should be rooted in evidence. Theists say they have evidence: personal experience of deity. No governing philosophy should be based on ignoring evidence, should it? 2. And at least Judeo-Christianity has evolved. Christianity is an evolution of Judaism adding the ideas a) that deity is not tribal or partisan but universal, b) strict rules of diet and behavior are not necessary, what is necessary are general guidelines such as "do unto others as you would have them do unto you". Christianity itself has evolved in many ways. Just one is the role the priesthood plays in mediating between humans and God. Both Catholics and Protestants now view that individuals come to God and that ministers/priests serve only as guides and helpers, not necessary intermediaries. 3. As knowledge and maturity of humans has increased, Judeo-Christianity has changed its position on issues (by applying general principles): slavery was OK in Paul's time, Christians decided it was wrong; interpretation of scripture has changed based on extrabiblical knowledge; and repudiation of sexism to name just 3. -
"Scientific" Evidence for Creation
lucaspa replied to MoMo's topic in Evolution, Morphology and Exobiology
Creation itself is a theological statement: God created. Any scientific evidence involves an additional statement(s): how God created. So, if you postulate that God created the universe by the Big Bang, galaxies, stars, and planets by gravity, life by chemistry, and the diversity of life by evolution, then you have LOTS of scientific evidence for creation. The difficulty, of course, is showing that these processes depend on God rather than work on their own. Yes, many of their arguments are analogical. Many of the arguments about design are analagies of human deisgn. However, the idea of "intelligent design" is predicated on the idea that ONLY intelligence can produce design. Since natural selection is an unintelligent process to give design, there goes the premise out the window. -
"Scientific" Evidence for Creation
lucaspa replied to MoMo's topic in Evolution, Morphology and Exobiology
"god-of-the-gaps". Creationism is a scientific theory. It was disproved/falsified in the period 1800-1859. What modern day creationists do is: 1. Deny the data falsifying the theory. 2. Basically use atheist theology that natural = without God and thus "no natural"/miracle = God as the basis of their search. The idea is that there is no "natural" explanation for certain phenomenon: the human species, irreducible complexity, complex specified information, design, etc. No. But it would challenge the religion of Fundamentalism -- which is the worship of a literal, inerrant Bible. Fundamentalism would hold that God created only one sentient species. The 3 major monotheisms -- Judaism, Christianity, and Islam -- would simply have it that the material processes God used to create the universe also created other sentient species. Presumably God would have revealed Himself to these species also and provided a path for them to understand and communicate with God. -
Microevolution, does it equal Macroevolution?
lucaspa replied to FreeThinker's topic in Evolution, Morphology and Exobiology
That doesn't make any sense to me. Please try again. What polymer? What is "express overtime in the population"? There are stretches of the DNA that are more prone to mutation than other stretches. Those are "hotspots". When we say "types of mutations" we mean substitution, addition, deletions, duplications, translocations, etc. And yes, subsitutions, deletions, and additions of single nucleotides are more common. But the mutation rate comprising all types of mutations on any spot in the genome is about 1 per person. Again, we are talking rate of mutations per individual. That automatically lumps all mutations together. The paper was looking at a flatworm C. elegans. They picked this because the worms are hermaphrodite, so they could compare populations that descended from a single individual. So they had a baseline genome -- the hermaphroditic parent -- as a starting point. Now, I'm not sure what you mean by "lack of direct observation in all levels biologically". Biology is about direct observation at all levels, from the genome to populations. A hot area in medicine is "single nucleotide polymorphisms" (SNPs or "snips") which is looking at single nucleotide differences in a single gene between individuals. This is often related to particular diseases. So what I see in medicine and biology is direct observation -- at least as much in other sciences if not more. In physics, for instance, subatomic particles are never directly observed. What is observed is their effects on other things. -
Microevolution, does it equal Macroevolution?
lucaspa replied to FreeThinker's topic in Evolution, Morphology and Exobiology
There have been studies. The mutation rate is about 1 per genome or individual. So you are a mutant, I am a mutant, and everyone posting on this board has a mutation. The current human population is 6 billion or so people. So there are that many mutations. The vast majority of mutations are neutral. That is, they neither help nor hinder the individual in the population. That is why most populations have such a huge reservoir of genetic variability among the individuals. Humans are unusual right now because we went thru a bottleneck about 150,000 years ago when there were only about 10-100 breeding pairs of humans -- not very many individuals and thus not much variation. This is different. Ants are a Family, which means there are a LOT of species of ants. It is this difference between species that you are calling "variance in ants". This is different than variance between individuals. Ants underwent what is called "adaptive radiation" and moved into a lot of vacant ecological niches (lifestyles), which is why there are so many different species. Evolution happens to populations, not individuals. That's why you don't have cows giving birth to goats. Over generations, the character of the population gradually shifts until the new population is different enough from the old one to be called a new species. If you plot the number of individual on the y-axis vs the trait (such as length of incisors) on the x-axis, you get a bell-shaped curve. Over generations, evolution (particularly with natural selection) shifts that bell-shaped curve either right or left on the x-axis. Say we get a shift of the incisors becoming longer as the population adapts to eating meat. Eventually, the curve will have shifted enough to the right such that the individual with the shortest incisor in the new curve will still have incisors longer than the individual with the longest incisor in the old curve. Is that clear or did I just completely confuse you? -
Microevolution, does it equal Macroevolution?
lucaspa replied to FreeThinker's topic in Evolution, Morphology and Exobiology
It can. Remember, most variation in sexually reproducing organisms comes from recombination -- mixing alleles. Again, most macroscopic traits are polygenic -- they are the result of interplay between many different genes. The definition of evolution is very broad. If you mean "descent with modification" -- which is the best short-hand definition -- that evolution happens is partly supported by the fact that there are mechanisms to introduce changes (mutations) into our DNA. But mutations alone won't cause changes in species. There is a type of natural selection called "stabilizing" or "purifying" selection. When a population is in a stable environment and is well-adapted, any change in DNA is going to move them off the fitness peak. In that case, natural selection is going to act to eliminate the "modifications of our DNA" and the population remains genetically stable. No. It is evolutionary biologists who came up with the terms "microevolution" and "macroevolution". Microevolution was coined to represent the changes seen in populations by population geneticists. A famous example would be the shift in coloring in the peppered moths in England. Macroevolution referred to the long term trends in lineages seen in the fossil record -- such as the transition in the horse lineage from a small, 5 toed species Hyracatherium (?) to the modern horse Equus that is large and has only 1 toe. Macroevolution involves multiple speciations but the questions are: what are the reasons for such large scale changes over time (and many species) within a lineage? The point where micro and macro evolution meet is speciation. In fact, speciation is macroevolution. Speciation (particularly in sexually reproducing organisms) involves processes in addition to the shuffling of alleles seen in microevolution. In particular, speciation involves reproductive isolation of two populations. Speciation also often involves separation of 2 populations of the same species, either by geography or by lifestyle. -
Microevolution, does it equal Macroevolution?
lucaspa replied to FreeThinker's topic in Evolution, Morphology and Exobiology
As I understand it, yes. Macroevolution involves speciation. In fact, many evolutionary biologists equate those: macroevolution = speciation. The reproductive isolation of the !Kung -- including unique alleles in that population -- is incipient macroevolution, IMO, because the end result would be a new species of Homo. I basically agree. The distinction serves an emotional and theological function for creationists. Microevolution is so widely observed that they cannot deny it. However, they have to preserve, at all costs, the idea that "kinds" cannot transform to other kinds. So they created (intelligent design:-) ) this artificial distinction between micro and macro evolution. They will allow fluctuations of alleles within species as long as speciation doesn't take place. Of course, then they have problems with that. They then admit that speciation occurs but try to draw a line with the slippery word "kinds". Look at the diagram on this page -- http://www.answersingenesis.org/home/area/magazines/docs/v22n3_liger.asp -- and compare it to the (only) diagram in Origin of Species. As far as I can see, they are the same! as long as you bear in mind that theres no evidence for the above mechanism, and that microevolution X lots can = macroevolution, theres nothing 'unscientific' about the terms. -
Microevolution, does it equal Macroevolution?
lucaspa replied to FreeThinker's topic in Evolution, Morphology and Exobiology
It can. In the mix and match and selection, some alleles will move to fixation (every individual has them) and some will be removed totally from the population. This shifts the bell-shaped curve of traits either right or left and can move it such that the new bell-shaped curve doesn't overlap the old one. I agree that evolution is a continuous phenomenon. However, evolutionary biologists, for convenience, do talk about about micro vs macroevolution. Micro is shifts of alleles within a population that does not necessarily lead to a new species. Macroevolution is the trends of species in an evolutionary lineage. The evolution of the horse is macroevolution. The trend is toward larger size, fewer toes, and changes in teeth to eat tougher grasses. There are exceptions to the trend, where a speciation will make a new species in the horse family smaller, but those all ended as extinctions. But you are correct it is creationists (not necessarily Christians) that really try to draw a hard and sharp line between micro and macro. The purpose is emotional and theological, not scientific or convenience. Creationists accept micro evolution but deny macro. IOW, they deny the sequence of individuals and speciations that led from a species of fish to amphibians, or from Hyracatherium to modern horses and zebras. Microevolution is "changes within populations and species".* Macroevolution is "the origin and diversification of higher taxa". "Many biologists consider the study of species and speciation to constitute the bridge between microevolution and macroevolution."* Douglas Futuyma, Evolutionary Biology, pg 447, 1998 "But we must ask, what exactly are these genera, families, orders, and so on? It was clear to Darwin, and it should be obvious to all today, that they are simply ever larger categories used to give names to ever larger clusters of related species. That's all these clusters, these higher taxa, really are: simply clusters of related species. Thus, in priniciple the evolution of a family should be no different in its basic nature, and should involve no different processes, from the evolution of a genus, since a family is nothing more than a collection of related genera. And genera are just collections of related species. The triumph of evolutionary biology in the 1930s and 1940s was the conclusion that the same principles of adaptive divergence just described -- primarily the processes of mutation and natural selection -- going on within species, accumulate to produce the differences we see between closely related species -- i.e., within genera. Q.E.D.: If adaptive modification within species explains the evolutionary differences between species within a genus, logically it must explain all the evolutionary change we see between families, orders, classes, phyla, and the kingdoms of life. Niles Eldredge, The Triumph of Evolution and the Failure of Creationism. pgs 76-77. -
Microevolution, does it equal Macroevolution?
lucaspa replied to FreeThinker's topic in Evolution, Morphology and Exobiology
To back Mokele, not necessarily. Especially when we start going to 5 or 10 loci (which is pretty common for polygenic traits). Are they difference species? No. Eventually, yes we will. Remember, what happens is that some alleles disappear from a population while new alleles become fixed. So, if we have 2 populations side by side, one undergoing selection for different alleles (population A), and the other not (population B), over generations Population A is going to have a completely different set of alleles than B. That's not the biological definition. The biological definition is that we have a different species when the populations do not interbreed, even when in close contact. Whether they can or not becomes irrelevant. The gene pools are separate when they don't interbreed even if they have the chance. The two are NOT "obviously differnt" Instead, the quote from Eldredge I gave says the processes of microevolution lead to macroevolution. If selection for a new environment happens to all of all of the original population, we end up with transformiing the entire population into a new species. This is difficult to test with interbreeding because we don't have a time machine to go back and retrieve members of the population 5,000 generations ago to see if they can interbreed with the members of the current population. So we test out sympatric and allopatric speciation -- comparing two populations separated by either geographical or ecological barriers. Let me go in reverse order. There are genes that control hybrid sterility. This paper discusses changes to those genes -- different alleles -- that result in hybrid insterility: 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. Your local library will have that article. If you have trouble, let me know and I can either attach the PDF file or cut and paste the relevant data. Allopatric speciation is well documented both in the wild and the lab. Instead of "gene shuffling", what you want is "gene flow" between the isolated population and the main population (A and B, respectively). And yes, speciation is a balance between isolation and gene flow. Where a population has a large range with different habitats, there is what is called "disruptive selection". This is where the sub-populations are being selected for different environments but gene flow is retarding the fixation of alleles. Humans today are undergoing disruptive selection. There is also sympatric speciation where population A and B are in the same geographic area but now isolated by a different ecological niche. Apple maggot flies is one example. Another recently documented example are 2 populations of salmon -- but one breeds in the shallows of the stream and the other breeds in the deeper center. Now they don't interbreed at all. Now what you are missing, I think, in your "gene shuffling" is that selection works such that a particular allele will become "fixed" in the population. That is, EVERYONE will have that that allele and no other allele. Also alleles will be dropped from the population so that NO ONE will have that allele. Thus, over the course of generations, some alleles can't be "shuffled" because they either aren't there anymore or there are no competitor alleles. If the environment for the peppered moths had continued with dark trees, the alleles for light colored moths would have disappeared from the population. So, natural selection working at what you call the microevolution level can create a population that has completely different alleles from the original. It could. IF it occurred in a Hox gene. These are high level developmental genes that control major body changes. For instance, a change in just ONE base converts a multilegged animal like a millipede into a 6 legged animal like an insect: 1a. http://www.nature.com/cgi-taf/DynaPage.taf?file=/nature/journal/vaop/ncurrent/full/nature716_fs.html Hox protein mutation and macroevolution of the insect body plan. Ronshaugen M, McGinnis N, McGinnis W. Nature 2002 Feb 21;415(6874):914-7 Right, and the number of differnt alleles changes from situation to situation. Sometimes it might take 1,000 new alleles, in another case only 1. Which is why I resist definiing evolution solely in terms of "changing allele frequencies". Speciation involves other processes such as population isolation, change in habits, and fixation and loss of alleles My original argument was that all dog breeds were just the result of gene shuffling and that no beneficial mutation of a gene has been documented. If this is our definition of microevolution, it is not the same as macroevolution. If we introduce mutations, and we would have to look at the genomes to find them, than the two become the same thing. Not entirely. There are also different genes. Remember gene duplication and chromosome duplication. These create new genes. Also, insertion and deletion mutations can change a gene so that it really has no functional relationship to the original allele. -
Microevolution, does it equal Macroevolution?
lucaspa replied to FreeThinker's topic in Evolution, Morphology and Exobiology
Microevolution also works on new alleles -- mutations. An allele that has been in the population for generations is not the only type of allele that can undergo positive selection, is it? If a new mutation is advantageous, then natural selection (which you seem to be equating with microevolution) will also select the new allele. But macroevolution can also be the result of shuffling of alleles, too. Most traits we can see are the sum of many genes. And different alleles of those genes will give different traits. If we are looking at say the shape of teeth, that is under the control of many genes. One set of alleles would give teeth better suited to eating plants and another better suited to eating meat. In an omnivore population in an evironment where plants are scarce but prey plentiful, an individual with teeth better suited to eating meat would have an advantage. So, those alleles contributing to those type of teeth would be kept and alleles for teeth for plant eating would be lost. Over many generations, the alleles for teeth for eating plants would disappear entirely from the population and only those alleles for teeth for meat eating remain. Not necessarily. That's not entirely true anymore. Nope, you could have speciation without any mutations. Simply separate the allele populations. However, you are getting close to a truth: macroevolution also involves reproductive isolation. However, since reproductive compatibility is also a multigenic trait, if you separate the allele packages entirely, then eventually you lose the ability to interbreed and produce fertile offspring. But I need to caution you here, the biological speciation concept only requires that populations DO NOT interbreed. Genetic incompatibility is only the most dramatic example of reproductive isolation. However, if because of behavior, differences in the size or shape of reproductive organs, cues as to mate selection, etc are operative, then you have 2 separate species even if, were you to use artificial insemination, you could produce fertile F1 hybrids. The fact on the ground would be that there are no F1 hybrids. "But we must ask, what exactly are these genera, families, orders, and so on? It was clear to Darwin, and it should be obvious to all today, that they are simply ever larger categories used to give names to ever larger clusters of related species. That's all these clusters, these higher taxa, really are: simply clusters of related species. Thus, in priniciple the evolution of a family should be no different in its basic nature, and should involve no different processes, from the evolution of a genus, since a family is nothing more than a collection of related genera. And genera are just collections of related species. The triumph of evolutionary biology in the 1930s and 1940s was the conclusion that the same principles of adaptive divergence just described -- primarily the processes of mutation and natural selection -- going on within species, accumulate to produce the differences we see between closely related species -- i.e., within genera. Q.E.D.: If adaptive modification within species explains the evolutionary differences between species within a genus, logically it must explain all the evolutionary change we see between families, orders, classes, phyla, and the kingdoms of life. Niles Eldredge, The Triumph of Evolution and the Failure of Creationism. pgs 76-77. [emphases in original] -
Bluenoise's answer is generally correct, but the situation is much more complicted for ES cells. Concentration gradients apply later in development. They have been well-studied in limb development and patterning. The concentration of 2 or more factors, for instance, tells an undifferentiated cell (but no longer an ES cell) to become a bone cell at a particular place in the limb. ES cells make their own differentiation factors and these act on the cell and on neighboring ES cells. It's called "autocrine/paracrine" action. ES cells must be stopped from differentiating. In cell culture this is done by either culturing the ES cells on a layer of killed mouse 3T3 cells or including Leukemia Inhibitory Factor (LIF) in the culture media. When LIF is withdrawn, the ES cells differentiate in random patterns. You will have a heart cell next to a bone cell next to an intestinal cell next to a nerve cell. When ES cells are implanted in a mass into an animal, basically the same random differentiation pattern happens. The result is a teratoma where you will have mixture of teeth, hair, intestine, muscle, cartilage, bone, etc. Scientists are just now figuring out what the differentiation factors are. And this is one area where ES cells are critical. No other cell is going to be able to be used as an assay for these very early developmental differentiation factors.
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Yes and no. There are a lot of claims in the article. Some are correct, others are not. It is true that many Americans oppose ES cell research because they have an ethical position that human life in the ethical, political sense begins at conception. However, we also have the ethical tradition that it is OK for one human to die so that many more can live. Our military personnel in Iraq and Afghanistan are part of that ethical position. It is OK to send them to get killed (even if they were drafted) in order to save people here in the US. It is also true that adult stem cells have been used to regenerate some tissues in animals and there are clinical trials using them. However, altho "Adult stem cell therapies are already being advertised and promoted ", these have not passed clinical trials. Talk about flim-flam!! Also, by far the most extensive source of biomedical research funds in the US is the federal government. What individual states can contribute is nothing in comparison to the budgets for NIH and NSF. California and other states are just doing a stop-gap. If ES cell research is to go anywhere, it must have federal funds. Both ES cells and adult stem cells have problems in being used in clinical trials. For instance, cord blood cells form bone marrow, but no other tissue reliably. The article didn't tell you that when it mentioned that those cells were being banked, did it? Many adult stem cells (there are several types) have been shown to have either limited ability to form tissues or limited ability to self-renew, or both. So, while claiming that Fox was preying on the ignorance of the public, this article does the same thing. Dust mote and logs. ES cells have unlimited ability to form tissues and unlimited ability to self-renew. But they come with their own problems. Adult stem cells tend to respond to signals in the local area and form the tissues of that area. ES cells form tissue without regard to where they are: they generate their own signals, apparently. Thus, much ES cell research is geared toward directing ES cells to form specific tissues. When implanted in a mass, ES cells form tumors called teratomas. When injected in a suspension, they don't. Go figure. IMO, ES cells are indispensable in understanding developmental problems such as spina bifida or Down's syndrome. Adult stem cells can't provide us with any of those answers because they are past that stage of development. OTOH, adult stem cells probably are a safer and more reliable route to treatment of some diseases or trauma, such as bone defects, osteoarthritis, heart attacks, kidney disease, making new blood vessels, etc. Places where you need a mass of stem cells in a particular shape. ES cells may be better for more diffuse diseases where individual cells need to be replaced. Parkinson's or muscular dystrophy would be two of those. So Michael Fox was not wrong: ES cell research does hold the most promise for his disease. But the point is that we will never find out what the promise of ES cells are unless we do the research! Fox is protesting that a narrow ethical position is being forced on the majority of the population.
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No, it's not. Most evolutionary biologists do NOT accept it. They follow the lead of Mayr, Futuyma, and the NAS and don't use that definition. It is the definition often encountered in online evolution vs creationism debates. But the debators are "evolutionists" but not evolutionary biologists. Frequency is the proportion of individuals that carry that allele. Remember, genes come in several forms -- called alleles. Each allele has a slightly different DNA sequence. Let's take a simple Mendelian example where there are only 2 alleles: A and B. If we have 100 individuals and 90 have A and 10 have B, then the frequency of A = 0.90 and the frequency of B = 0.1 Now, if this was a very large population and there was no natural selection and there was no selective mating (completely random mating), that frequency would not change from generation to generation. We would always find that the frequency of A = 0.90 and B = 0.10. However, in this small of a population two things are going to change the frequency of A and B. So, after several generations instead of having 90 individuals with A and 10 with B, you might see 70 with A and 30 with B. Over time, the frequency will shift such that all the individuals will have either B or A and none will have the other.
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Well, it was in this thread. And you are using the same ellipses I am. NAS is writing for a lay audience. Thus there defiinition is not as detailed as Futuyma's. However, I can't see anywhere that their's is in contradiction to Futuyma's. In which case, you need to demonstrate how it is not "sharp". That isn't what Futuyma states. Let's look at Futuyma again: "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. Note what I bolded. Futuyma is staking out the boundaries -- the "big tent", if I may borrow a phrase from Phillip Johnson. What you are reading is a progression that says changes in allele frequencies is all you need to get new species. "begins with ... and ends ''. But to get the diversity of life we see now, you need more than a change of allele frequencies. For instance, the peppered moth has vacillated and you don't have any more diversity in species that you had before. Same with the Grant studies on the Galapagos finches. This is Mayr's point: change in allele frequencies is not enough -- by themselves -- to get a new species. Yet if one explores the statement "descent with modification" closer I'd say it is not too far from change of allele frequencies over time. It does not (at least as I would interpret it) require speciation for instance. But it includes speciation. "change in allele frequencies" does not necessarily include speciation. It can include that, but as I keep pointing out, there are numerous examples of changing frequencies without getting a new species. "Descent with modification" is necessarily going to include both micro and macroevolution -- since macroevolution is also "descent with modification". And everything below that would be a shuffling of alleles. Yet, it does not define how much shuffling is needed to accept it as a evolutionary process. And this in turn also has an impact on evolution of proakaryotes. Here you do not have easily definable endpoint frequencies (e.g. fixation) due to extensive horizontal gene transfer. BTW the genetic species concept as applied to prokaryotes is an extremely arbitrary distinction (70% hybridization). re fixation: Sigh. You didn't read post #71, did you? Yes, I mistakenly did give that impression. Since you apparently won't go back and read the post, let me quote it here: "Let's start from the top. #1 is correct and my original claim was poorly worded. It does look like I'm saying that shifting allele frequencies within a population is not part of evolution. "Biological evolution may be slight ...; 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" Futuyma op cit, pg 4 Instead, what I meant to say was that loss of alleles and fixation of alleles is an inevitable result of evolution -- common ancestry: "The geneology of the genes in the present population is said to coalesce to a single common ancestor [individual]. Because that ancestor represents one of the several original alleles, the population, descended entirely from that ancestor, must eventually become monomorphic: one or the other of the original alleles becomes fixed (reaches a frequency of 1.00)" D. Futuyma, Evolutionary Biology, pg 299 Of course, that means that the other is lost. So, let me rephrase: When evolution -- changes in populations -- happens, some alleles must become fixed and other alleles must become lost." Let me give another disadvantage of the "evolution is the change of allele frequencies" definition. In the creationism vs evolution debate, "change in allele frequency" is often used to try to win a "slam dunk". After all, no one can doubt that this happens. So, evolution is correct, right? Nope, because people extrapolate from that limited definition to macroevolution. And it is here that creationists nail their ass to the wall. Because, as Mayr says and the data says, you can't extrapolate this by itself. There are other processes that come into play during speciation -- the processes that lead to reproductive isolation. And it is argued that there are other processes yet that come into play during macroevolution. So, if you try to go with the "slam dunk" that evolution is "change in allele frequencies" and thus evolution is "proven", the smart creationist is going to reply that changes in allele frequencies don't result in new species, and will cite not only the peppered moths and the Grant study, but all of Fisher's and Dobzhansky's studies in population genetics. Now the whole basis of your position of evolution "proved" is down the drain. The evidence for speciation and macroevolution don't count because "change in allele frequencies" has been "shown" not to result in new species. IF, OTOH, you use the correct, broader definition of either Futuyma or the NAS, then "change in allele frequencies" is only part of evolution. Then the peppered moth and Grant studies become "proof" for that part. And the other evidence on speciation and macroevolution are still valid because they apply to their parts of evolution.
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Yes, you did. Otherwise I woudn't have objected. OK, now your point is becoming clearer. You are using "fuel" as getting more engery out of as substance than we have to expend in getting the substance. That's not the standard definition of fuel -- thus the confusion -- but I see your point. Yes, we have to expend more energy making hydrogen than we are going to get out of it. In the case of oil and coal, the energy expenditure to make them was by geological processes, not us. OK, I understand your complaint now and it is a valid complaint. The energy to make the hydrogen by hydrolysis has to come from somewhere. That energy expenditure -- and the environmental consquences -- are not discussed. That is essentially my complaint about hydrogen not being a solution to pollution. If we use coal to generate the electricity for hydrolysis (the most abundant and cheapest means for electrical generation), then we simply shift pollution from the middle of the cities to the whole planet with a net increase in the level of pollution. I think ethanol can make the same claim. After all, again the sun is doing the work of generating the energy. So if you use ethanol vehicles for planting, cultivating, and conversion of the organics to ethanol, then you get a positive energy balance.
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You got it from me! I'm the one that posted it. No, it can't. Because it leaves out many of the most important things: such as speciation. Evolution includes "changes in allele frequency", but can't be "changes in allele frequency". The NAS uses "descent with modification" as the minimal definition of evolution: Appendix and Frequently Asked Questions Science and Creationism, A View from the NAS, the section "What is Evolution?" says: "Evolution in its broadest sense explains that what we see today is different from what existed in the past. Galaxies, stars, the solar system, and Earth have changed through time, and so has life on Earth. "Biological evolution concerns changes in living things during the history of life on Earth. It explains that living things share common ancestors. Over time, biological processes such as natural selection give rise to new species. Darwin called this process "descent with modification," which remains a good definition of biological evolution today." pg 27 You never made any statement that Futuyma's definition of evolution was not "sharp". The NAS definition for evolution of "descent with modification" is both sharp and universal. Of course, I am the one that agreed that a precise definition of species was impossible -- because evolution is true. And yes, biological species concept applies only to sexually reproducing species. If you are looking at fossils, you use the morphological species concept. If prokaryotes, then it's the genetic species concept. All of them are "fuzzy", because transformation of one species to another is simply not sharp and definitive. Regarding species while what you said has some truth in it, you have consider that there are inherent problems with the definition proposed by Mayr. Remember, there were species concepts long before evolution was thought of. Linneaus was a creationist, after all. And the contemporaries of Darwin that classified and named new species were adherents of Special Creation. Now there is an intertwining because evolution is recognized as true. Thus we now have "phylogenetic species concept" and even an "evolutionary species concept". The fuzziness of species had an impact in realizing evolution existed in the first place, but not on the definition -- see at end of post. Which I had already decided I misspoke when I said that. Look post #71. "Nor shall I discuss here the various definitions which have been given of of the term species. No one definition has satisfied all naturalists; yet every naturalist knows vaguely what he means when he speaks of a species. Generally the term includes the unknown element of a distanct act of creation. The term 'variety' is almost equally difficult to define; but here community of descent is almost universally implied, though it can rarely be proved." Charles Darwin, Origin of the Species, 6th edition, pg 58 "Hence, in determining whether a form should be ranked as a species or a variety, the opinion of naturalists having sound judgement and wide experience seems the only guide to follow. We must, however, in many cases, decide by a majority of naturalists, for few well-marked and wll-known varieties can be named which have not been ranked as species by at least some competent judge." pg 62 "Some few naturalists maintain that animals never present varieties; but then these same naturalists rank the lightest difference as of specific value; and when the same indetical form is met with in two distant countries, or in two geological formaions, they believe that two distinct species are hidden under the same dress. The term species thus comes to be a mere useless abstraction, implying and assuming a separate act of creation. It is certain that many forms, considered by highly-competent judges to be varieties, resemble species so completely in character, that they have been thus ranked by other highly-competent judeges. But to discuss whether they ought to be called species or varieties, before any definition of these terms has been generally accepted, is vainly to beat the air." pg 64 Darwin describes the work of De Candolle, who had done an exhaustive study of oak species and varieties. "De Candolle then goes on to say that he gives the rank of species to the forms that differ by characters never varying on the same tree, and never found connected by intermediate states. After this discussion, the result of so much labour, he emphatically remarks: 'They are mistaken, who repeat that the greater part of our species are clearly limited, and that the doubtful species are in a feeble minority. This seems to gbe true, so long as a genus is imperfectly known, and its species were founded upon a few specimens, that is to say, were provisional. Just as we come to know them better, imtermediate forms flow in, and doubts as to specific limits augment.'" pg 65 "Finally, De Candolle admits that out of the 300 species, which will be enumerated in hs Prodromus as belonging to the oak family, at least two-thirds are provisional species, that is, are not known strictly to fulfil the definition above given of a true species. It should be added that De Candolle no longer believes that species ae immutable creations, but concludes that the derivative theory is the most natural one, 'and the most accordant with the known facts in paleontology, geographical botany and zoology, of anatomical structure and classification.'" pg 65 Darwin concludes: "Certainly no clear line of demarcation has as yet been drawn between species and sub-species --that is, the forms which in the opinion of some naturalists come very near to, but do not quite arrive at, the rank of species: or, again, between sub-species and well-marked varieties, or between lesser varieties and individual differences. These differences blend into each other by an insensible series; and a series impresses the mind with the idea of an actual passage." Charles Darwin, Origin of the Species, 6th edition, pg 66
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That makes no sense. Hybrid cars are simpler and cut emissions and increase mileage to levels comparable for hydrogen vehicles. Remember, hydrogen vehicles don't necessarily get better mileage, they simply don't use oil (at least not at the car end). Unless you live in Arizona or the Namibian desert, solar is too unreliable and inefficient to power a car. So, for you, get either an electric car that you plug in at night, or a hybrid. My Toyota Prius does not leave a foul-smelling smoke. It's "super low emissions". The biggest danger would be when it's running on batteries and the biker would never hear it coming and might make an ill-advised left turn.
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But that's true of fossil fuels, too. However, the addition of energy was by the sun and geology several million years ago. As we get oil to use in cars, it is fuel -- for the cars. Hydrogen would be the same thing -- fuel for the cars. Again, that is also true of oil. Oil is a way of turning solar energy into a more convenient fuel and storing it. It's just that we, today, do not have to do the energy input; that was done by the sun via photosynthetic plants tens or hundreds of millions of years ago. Then geology compressed the plants and converted them to coal and oil -- again using energy. Also don't forget that refining the oil takes energy. There we agree. And wind and solar simply are not available in large enough quantities to make the amount of hydrogen we would need if we switched all our vehicles to hydrogen.
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Again, the Second Law of Thermodynamics states that the energy needed to strip the hydrogen atoms and then using them to move the car must be less efficient than burning the hydrocarbons as fuel for moving the car down the road. Also note that one of the advantages of hydrogen is that combustion doesn't release greenhouse gasses -- all you get is water. BUT, in your system, we still get as much CO2 emissions as we would with gasoline. If your hydrocarbon source is coal, then we also have the problem of sulfuric acid and nitrous oxide emission. We can take care of a lot of that in coal plants by scrubbers, but in individual cars? Nope.
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So what you are saying is: these guys are "notable contributors" to evolutionary thought and they are all atheists, therefore evolution is atheism. You do realize that you are using the Argument from Authority, don't you? Remember, this started out as a counter to Coulter's assertion/theory that people must either choose evolution or theism -- that evolution and theism cannot co-exist. Evolutionary biologists that are both -- and even you can't belittle Dobzhansky or Fisher -- are evidence refuting her theory. So tell me, why do you want us to think Coulter's theory is true?
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shoot, forgot to attach the file to the last post. Berry- threat to creationists.txt
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You said you could falsify Yahweh. Want me to get the quote by you? Now you seem to be backing off. What "current physical evidence"? The key here is current. At the time, there was indeed physical evidence: the risen Jesus with nail holes and a wound in the side. So it's not the same argument. In this case, the miracle healings, the loaves and fishes, et. there was evidence. It's just that the evidence does not persist to our time. You've confused apples with oranges. As you noted, science is incapable of testing the Oomphalos theory -- the idea that God only made the universe LOOK old. The refutation for that theory is not in science. It's in theology. Within Christianity, that theory is not valid. False dichotomy. There are many positions other than these two. But no, they don't believe in the same deity, but not for the reason you think. A person who believes the Bible is literally true has the literal Bible as a god. It's the equivalent of a graven image. It's not Yahweh. There are several different statements here: 1. God exists. 2. God created the universe. 3. God used creationism to create the universe. Yes, I understand that you don't make the distinction between method and existence, but that is the error. It's obvious why you don't want to make the distinction and you want to tie the 3 statements together: it's the only way you can falsify God and make atheism look valid. But it's equally obvious that the statements are separate. If God doesn't create the way stated by the theory of creationism, that does not mean God didn't create. All it says is that God didn't create THAT way. All you can do is say "a literal interpretation of the Bible is disproven". You are making the same non-sequitor mistake as creationists: if Yahweh did not create this way, then Yahweh does not exist. You can readily see that this does-not-follow. I'm going to attach a file. It's part of Hiram Berry's essay in Is God a Creationist? edited by Roland Frye. This is a critique of creationism from the standpoint of Christian theology that came out after the McLean vs Arkansas trial in 1982. Berry does a much more extensive job of showing that it is not valid to make the link between existence and method that you, and creationists, want to make. No, it's not. It's simply a way to get you off the hook of being unable to disprove the existence of God. Instead of showing the weakness of atheism in this regard, you are trying to shift the blame to theism by saying "God can mean anything." But you haven't demonstrated that Christians are using the word in that sense. But, that isn't what I'm saying. I'm not defining the word "science". Let's follow the logic from the perspective of Judeo-Christianity. 1. Yahweh exists. 2. Yahweh created the universe and everything in it. therefore 3. Everything in the universe was put there by Yahweh, either directly or indirectly. 4. Yahweh is honest. therefore 5 Studying the physical universe is studying Yahweh's Creation and 6. Such study is going to tell you how Yahweh created. Notice that #1 and 2 comes from outside science. Those are conclusions reached by other evidence theists consider valid. Those conclusions are then used as premises in the present argument. However, starting from those premises, it is a conclusion that science (the study of the physical universe) is going to tell you how Yahweh created. Yahweh is not "what is". Instead, "what is" is a result of the creative processes used by Yahweh. Yahweh is an entity independent of the universe. Creationism in all its forms -- from YEC to the quasi-ID promoted by Coulter -- is a method by which Yahweh is said to have created. So, from the perspective of a theist (which you are not required to adhere to), evolution becomes simply the method Yahweh used to create. No conflict between evolution and Christianity. It also means that evolution does not falsify Yahweh. Because the core statements concerning Yahweh don't require a specific method of creation.
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I said "at least half of all evolutionary biologists", not "most". Again you are trying to change terms. Looking at scientists in general -- which would include evolutionary biologists -- 40% are theist with a very conservative definition of theism. EJ Larson and L Witham, Scientists are still keeping the faith, Nature, 286: 435-436, 1997 (April 3) "Forget philosophy for a moment; the simple empirics of the past hundred years should suffice. Darwin himself was agnostic (having lost his beliefs upon the tragic death of his favorite daughter), but the great American botanist Asa Gray, who favored natural selection and wrote a book entitled Darwiniana, was a devout Christian. Move forward 50 years: Charles D. Walcott, discoverer of the Burgess Shale fossils, was a convinced Darwinian and an equally firm Christian, who believed that God had ordained natural selection to construct a history of life according to His plans and purposes. Move on another 50 years to the two greatest evolutionists of our generation: G.G. Simpson was a humanist agnostic, Theodosius Dobzhansky a believing Russian Orthodox. Either half my colleagues are enormously stupid, or else the science of Darwinism is fully compatible with conventional religious beliefs -- and equally compatible with atheism, thus proving that the two great realms of nature's factuality and the source of human morality do not strongly overlap." SJ Gould, Impeaching a self-appointed judge. Scientific American, 267:79-80, July 1992. And you get to define "important". So that you can exclude anyone you don't want. See the examples: His work in paleontology was solid and he is considered an important contributor to paleontology. His work on the relationship of evolution to religion is remembered, but it is a sideline. No, he's an evolutionary biologist and has written one of the most popular scientific textbooks. He's a charter member of NCSE and the most effective defender of evolution against attempts to include creationism in science class. He was a star witness for evolution at the Dover trial and it was his testimony that caused Judge Jones to rule that IC had been refuted. Walcott discovered the Burgess Shale and thought a lot about the Cambrian explosion. This simply shows your religious bias, pettiness, and attempt to exclude data you don't like. As I said, it's selective data. Equivalent to Gish looking at some juvenile forms of birds that have claws and declaring Archie to be "fully a bird". Or looking at the one paper that showed Lucy did not have a fully modern gait and saying she walked like an ape. But among his contemporaries he was. And I can't find too many publications in peer-reviewed journals, either. Can you? Which also characterizes Walcott. But you apparently don't know him. I never said they were. Science is agnostic. Which means it does not exclude either theism or atheism. See Gould above. But the point is that science and theism are not mutually exclusive. And that is the argument that is effective against Coulter and her cronies. If you try to make science ONLY atheist, then you play right into her hands. I submit that you are promoting a different superstition/faith that is no more scientific than creationism. Also, theism is rational. I said "at least half". And the only reason you think you are right is that you exclude any theist from being "great evolutionary biologist". Again, this reminds me of Gish. He excludes all transitional fossils as being transitionals, then he says "there are no transitional fossils". The Judeo-Christian deity is not anthropomorphic. But anyway, I presume you can quote Gould? Did you read what you wrote? You never did research, but you know? Yet I have done some research. And this is where your faith threatens science. We can disprove many of the stories we tell children. We can falsify Santa Claus, Tooth Fairy, etc. In fact, I have inadvertently done the experiments that disproved TF. As I said, there is reason to doubt the data. BUT you can NEVER use theory to disprove data or even show it "unlikely" That is simply dreadful science. Take a look at this below. Tachyons are a lot like God: can't detect and are a pain in the ass. Yet what is our scientific attitude toward them? Do we say they are "unlikely"? "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.
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Aren't most capsules made from gelatin? Or some form of vegetable fiber. In that case, the natural color is tan. I think agents are added for other colors. http://www.capsugel.com/ http://www.emptycaps.com/ http://www.capsuleking.com/?gclid=CPKgw76m3YcCFQimHgodPHv1lg
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"Yahweh" is the Judeo-Christian deity. How do you think Yahweh has been disproved by science? Cite particular papers if possible. But can science disprove miracles? That is, science being conducted properly. Not usually. Miracles are one-time events. In order for science to study them, they must leave evidence we can study today. Most miracles don't do that. Let me try one example: the Resurrection. Essential to Christianity as a historical event. And a miracle. Now, the usual way to try to use "science" to deny the Resurrection is to say "dead people don't rise", therefore Yeshu (Jesus) did not resurrect. But is this correct science? Scientifically, what you have with the dead bodies is a THEORY, based upon the individual data points of dead bodies we have observed. The *theory* states that a person dead will not come back to life. However, you can never prove a theory, you can only test it. So far, all the data supports that theory. BUT, Yeshu's possible resurrection is DATA. That is the essseintial point. Data always overthrows theory. But you cannot use theory reject data. You cannot generalize from what you have observed to reject the next observation. Now, Yeshu's supposed resurrection is not solid data. It happened a long time ago and it left no physical consequences around that we can objectively, intersubjectively study today. So, we are allowed to view the event as an anomaly and do not have to revise the theory. But we simply CANNOT use the theory to say the data (the resurrection) never happened. Let me give you another example of theory and data. We have released several rocks and seen them fall. So we devise a theory of gravity that says that ALL unsupported objects will fall. This works well as we drop bricks, limbs, seashells, leaves, etc. But then we try a helium balloon. It goes up. Do we deny that it goes up? NO. Instead, we revise the theory to: all objects that mass more than the air they displace will fall when unsupported. The THEORY gets changed. In the case of Yeshu, IF we could find objecitve data to confirm the event happened, then our theory would be: all humans who die remain dead except when deity interferes and reverses the process.