This is what I don't get - how someone can believe in "micro-evolution" but not "macro-evolution." If species can change, as you acknowledge (I think), then how can longer time frames not produce larger changes? It seems to me that's like saying you believe that in 20 years water can form trenches but you don't believe that in a million it can form river beds.
Snipped that a bit to focus.
Your example is consistant but what I am talking about is not. Your example uses water twice, hence an existing trait.
I would for example believe that if we took two small hairy dogs and bred them together, we might get an even small hairier dog. We manipulate existing traits all the time, especially in agriculture.
However creating a new trait is entirely different. Your example would say that if in 20 years water can form trenches, but why don't I believe in 100 million years it can build a complex dam generating electricity.
The latter requires complexity, new materials, etc. That (for obvious reasons) is the leap I am not willing to make.
Evolution has been shown to help manipulate, in a gradual manner, existing traits. I have not seen proof of new abilities or traits though.
(as a hint i will give you the definition from dictionary.com
biomechanics:
1. (used with a sing. verb) The study of the mechanics of a living body, especially of the forces exerted by muscles and gravity on the skeletal structure.
2. (used with a pl. verb) The mechanics of a part or function of a living body, such as of the heart or of locomotion.
)
you were using biochemical appropriately before, why the sudden switch to biomechanical which has very little to do with a molecule by molecule model of evolution.
i thought you would be (re)-banned by now
you're playing games and can't answer me---you don't have clue as to how amino acids formed to DNA-based lifeforms
...and I can't be re-banned if I haven't banned already.
I'm beginning to think brussle will have to settle for being my internet stalker, though. Apparently, if he can keep track of the boogie man he wont have to answer any hard questions. 'Looks like you're going for the same cheap thrills he is.
you're playing games and can't answer me---you don't have clue as to how amino acids formed to DNA-based lifeforms
...and I can't be re-banned if I haven't banned already.
I'm beginning to think brussle will have to settle for being my internet stalker, though. Apparently, if he can keep track of the boogie man he wont have to answer any hard questions. 'Looks like you're going for the same cheap thrills he is.
You should both be ashamed of yourselves.
do you know any science at all... i mean i need a starting point as far as discussing this any further. how far did you get in high school? or perhaps (though I am not sure of this) college? what science have you taken? how much of it do you trust? i need to know these things before i can discuss this issue with you because i wish not to waste words.
I remember you. BRussell's very nice. He's no stalker, he's a proud father.
Quote:
Originally posted by ena
you're playing games and can't answer me---you don't have clue as to how amino acids formed to DNA-based lifeforms
I'm a real spanner! DARWIN IS A WANKER, Jesus told me!
Aaanyway, amino acids. It's been a while since I boned up on proteins and evolutionary processes, so forgive me if I'm a bit rusty.
So... let's take the Markovian model of evolution which assumes that amino acids mutate independently of each other with probabilities which depend only on the amino acids and on the amount of evolution. In mathematical terms we can describe the model with mutation matrices: a mutation matrix, denoted by M, describes the probabilities of amino acid mutations for a given period of evolution:
Amino acids appear in nature with different frequencies. These frequencies are denoted by fi and correspond to the steady state of the Markov process defined by the matrix M, that is, the vector f is any of the columns of ? (M multiplied by itself an infinite number of times) or the eigenvector of M whose corresponding eigenvalue is 1 (M f = f). When we find a mutation in aligned sequences, we cannot distinguish which one mutated into which, or whether a third amino acid mutated into them. This implies a simple relation for the entries of M:
M describes mutations over a given period of evolution. We must quantify this amount of change in a mathematically meaningful way. Dayhoff et. al.[3] introduced the term PAM (point accepted mutation) unit.
Definition 1.1 _ A 1-PAM unit is the amount of evolution which will change, on average, ? of the amino acids. In mathematical terms, this is expressed as a matrix M such that ? where fi is the frequency of the ith amino acid.
I'll post some more in a minute. I'm glad to be able to help you with your difficulties understanding ammino [sic] acids.
University of Chicago press release. 31 March 1988
How did life begin? Biochemical evolution on mineral surfaces
How did life begin on Earth? University of Chicago geophysicist Joseph V. Smith, in a Proceedings of the National Academy of Sciences paper published Tuesday, March 31, provides a theory for how small organic molecules may have been able to assemble on the surfaces of minerals into self-replicating biomolecules--the essential building blocks of life.
"The problem with most theories on the origin of life is that there is too much water around for the kind of organic chemistry that needed to take place," said Smith, Louis Block Professor in the Geophysical Sciences. "Synthesis of biomolecules from organic compounds dispersed in aqueous `soups' require a mechanism for concentrating the organic species next to each other, and biochemically significant polymers--like polypeptides and ribonucleic acids--must be protected from photochemical destruction by solar radiation."
Smith postulates that this chemistry could have been facilitated by silica-rich minerals resembling zeolites, porous crystals with channels running through them. Most zeolites are hydrophilic--water-loving--and tend to absorb water from their surroundings. But certain synthetic zeolites are organophilic, preferentially absorbing organic materials out of water.
A naturally occurring organophilic zeolite--called mutinaite--was recently discovered in Antarctica, and Smith thinks that this mineral could provide the key to the chemical evolution that led to the origin of life. It's possible that mutinaite, which has aluminum in place of silica, loses aluminum at its surface to become silica-rich through weathering, Smith said. A small amount of remaining aluminum would provide the catalytic centers for assembling organic molecules into polymers.
"For many years, I've wondered if such a material could occur in nature," said Smith. If small organic molecules, like amino acids, could accumulate in the pores of a zeolite, the mineral surface could have provided the catalytic framework for assembling them into polymers and protecting them from destruction by the sun.
A famous experiment performed at the University of Chicago in 1954 by then-graduate student Stanley Miller and his advisor, the Nobel laureate chemist Harold Urey, showed that amino acids, which make up the proteins found in all living organisms, could form from chemicals in the atmosphere combined with water and lightening.
[snip]
Amino acids occur naturally in right-handed and left-handed forms, but only the left-handed forms are found in the proteins of living organisms. Smith said, "It's probably an accident that only the left-handed form is used, but it may have started in a zeolite with a left-handed channel." Zeolites with one-dimensional channels could have provided the template for assembly of only one version of the amino acids into the first primitive proteins.
Smith plans a trip to Australia, where some of the oldest and least-metamorphosed rocks and minerals are found, to look for more naturally occurring organophilic zeolites like the mutinaite found in Antarctica. He's hoping these minerals still contain evidence of primary biocatalysis. Further research will include chemical experiments to see if the zeolites actually carry out the chemistry he proposes, and the use of computer models to study the structure of the channels.
Smith's work on zeolites was funded by Union Carbide Corporation/UOP, the National Science Foundation, the American Chemical Society, Exxon Educational Foundation, Mobil Research Foundation and Chevron Corporation.
Evolution has been shown to help manipulate, in a gradual manner, existing traits. I have not seen proof of new abilities or traits though.
trumptman, I think i have your answer. Jaw bones are the result of a modified gill (fetuses and some new borns actually have gills), that much has been shown developmentally. Teeth are basically modified scales of the jaw bone, that also has been shown developmentally. Evolutionarily, it is suspected that gills developed from the vasculature that is seen in sponges and other sea dwelling species that dont have gills (this has not been proven), they then developed into jaws, and jaws became teeth, and teeth became tusks etc and who knows what. So to answer that question, and in reference to BRussell's post, small easily understood and realizable changes can when one occurs on top of the other produce two traits (gills and say tusks) that are apparently unrelated to eachother. If you grant that small changes can occur then it (in most cases) necessarily follows that significant changes can occur.
I remember you. BRussell's very nice. He's no stalker, he's a proud father.
Aaanyway, amino acids. It's been a while since I boned up on proteins and evolutionary processes, so forgive me if I'm a bit rusty.
So... let's take the Markovian model of evolution which assumes that amino acids mutate independently of each other with probabilities which depend only on the amino acids and on the amount of evolution. In mathematical terms we can describe the model with mutation matrices: a mutation matrix, denoted by M, describes the probabilities of amino acid mutations for a given period of evolution:
Amino acids appear in nature with different frequencies. These frequencies are denoted by fi and correspond to the steady state of the Markov process defined by the matrix M, that is, the vector f is any of the columns of ? (M multiplied by itself an infinite number of times) or the eigenvector of M whose corresponding eigenvalue is 1 (M f = f). When we find a mutation in aligned sequences, we cannot distinguish which one mutated into which, or whether a third amino acid mutated into them. This implies a simple relation for the entries of M:
M describes mutations over a given period of evolution. We must quantify this amount of change in a mathematically meaningful way. Dayhoff et. al.[3] introduced the term PAM (point accepted mutation) unit.
Definition 1.1 _ A 1-PAM unit is the amount of evolution which will change, on average, ? of the amino acids. In mathematical terms, this is expressed as a matrix M such that ? where fi is the frequency of the ith amino acid.
I'll post some more in a minute. I'm glad to be able to help you with your difficulties understanding ammino [sic] acids.
...very nice, but just as materialistic. You are just restating a theory with plenty of scientific phrasing. You aren't giving answers---you're bludgening the thread with technical jargon.
where is the roadmap: enitity to entity until we have DNA-based lifeforms?
what did the intermidiate forms exist in?
long did this take?
you don't have any answers---you accept all of this on blind faith.
Hell, I'm on a roll. About the thorny problem of the impossible eye. Turns out it's very simple.
Quote:
Edward H. Hagen, Institute for Theoretical Biology, Berlin, quoth
Richard Dawkins wrote a very popular book called the Selfish Gene that explained, for a popular audience, many of the exciting new theories and discoveries being made in evolutionary biology in the 1960?s and 70?s. The metaphor Dawkins chose, the selfish gene, was an extremely powerful metaphor, so powerful that it has often overshadowed the science itself! The controversies that swirl around EP are often tightly bound up with Dawkins? metaphor. If our genes are selfish, are we all, deep down, unalterably selfish ourselves? Why did Dawkins chose this metaphor, what does it really mean, and what are its implications for EP and human nature?
Simplifying greatly for the sake of the argument, there is a molecule, called a nucleotide, that comes in four different types, A, C, G, & T. Large numbers of these nucleotides can be linked together in a linear strand to make a much bigger molecule called DNA. Schematically, DNA looks like this: ACGTGCCT?etc. Human DNA consists of about 3 billion nucleotides chained together. Simplifying greatly again, small sections of the DNA strand called ?genes?, which are usually several hundred to several thousand nucleotides long, are able to create a different type of long, linear molecule called a protein. Proteins are a kind of plastic?technically, a polymer?that, like the DNA chain, are made up of a small number of different molecular building blocks called amino acids (there are 20 different amino acid building blocks ). Just as the different chemical structure of the plastic in a plastic bag versus the chemical structure of the plastic in dental floss versus the chemical structure of the plastic in bullet-proof vests gives these different materials very different properties, the exact sequence of the different amino acids in a particular protein determines its biological properties. Different amino acid sequences give different proteins very different properties.
To summarize, the sequence of nucleotides in small sections of our DNA (called genes) determines the sequence of amino acids of proteins created by the genes, and these amino acid sequences determine the proteins? biological properties. Although scientists are still debating the exact number, DNA contains somewhere between 30,000 and 60,000 different genes, and can therefore create between 30,000 and 60,000 different proteins, each with unique properties. As I mentioned, proteins are a kind of plastic, so our DNA functions, in part, to create a large number of different plastics with different properties. These highly specialized plastics with very special biological properties are what our bodies are made of. DNA is a kind of lumber yard that provides, among other things, a large number of plastic building materials for making organisms.
Simplifying once more (this time by ignoring sex), individuals pass on an exact copy of their DNA chain to their offspring: if my body is made up of a particular set of plastics, because my offspring has an exact copy of my DNA, my offspring?s body will be make up of exactly the same set of plastics, and so it will be exactly like me. Occasionally, however, one of the molecules in the DNA chain (i.e., one of the A, C, G, or T nucleotides), can become mutated (altered) by cosmic radiation, environmental toxins, etc.; these mutagens turn one type of nucleotide into another type of nucleotide (e.g., an A turns into G). If I pass on this mutated DNA, where only one of the 3 billion nucleotides is different from my own, then my offspring will be made of proteins that are almost exactly like mine, except for the protein which was made by the mutated section of DNA (the mutated gene), which will be a different protein with different properties. My offspring will not be exactly like me?he will be said to have a different phenotype (body type).
Imagine that the gene that was mutated was the gene that made the plastic forming the lens of the eye. This plastic has a very special property: it is almost completely transparent. Most proteins, like those forming your skin, muscles, hair, etc., are not transparent. Because my offspring has a mutated form of the lens gene, there are now two types of genes in the population that make the lens protein: the normal version, possessed by most individuals (which I will call Tnormal, for normal transparency) and the mutated version possessed by my offspring. Different forms of the same gene are called alleles. Because it is far easier to make something worse than it is to make it better, most of the time when the gene producing the lens protein is mutated (and this happens very rarely), the altered lens protein produced by the mutated gene will not be as transparent as the original version (so I will label this allele Tlow, for low transparency). My offspring will therefore not be able to see as well as other members of his species who have the Tnormal allele, and thus normal versions of the lens protein.
Let?s assume that my offspring?s lens protein is only slightly less transparent than the normal version. He will be able to live his life and have offspring. The population will therefore contain a mix of lens alleles; most of the population will have Tnormal, but some will have Tlow. Because those with the Tlow allele will not be able to see quite as well as other members of their species possessing Tnormal, on average they will not have as many offspring. Perhaps they notice prey slightly less often, and thus not have quite as much food, or perhaps they fail to notice predators slightly more often, and will therefore be killed and eaten at a slightly higher frequency. Over many, many generations, the fraction of individuals with the Tlow allele will decrease relative to those with the Tnormal allele simply because individuals possessing the Tlow allele produce, on average, fewer offspring. We say that the Tlow allele producing the less transparent lens protein is selected against, and that the frequency of this allele decreases with time. Notice that, if the total population size remains constant, that the decrease in frequency of the Tlow allele results in an increase in the frequency of the Tnormal allele.
Imagine another mutation of the normal lens allele, creating a third allele (Tsuper) that produces a super transparent lens protein. The population now contains three alleles, Tlow, Tnormal, and Tsuper. Individuals possessing the Tsuper allele detect prey, on average, at slightly higher frequencies, and thus have more food, and they more frequently detect predators and therefore are eaten slightly less frequently. As a consequence, on average, they have more offspring than individuals possessing Tnormal. Over many, many generations, the frequency of the Tsuper allele will increase in the population, whereas the frequencies of the Tnormal and Tlow alleles will decrease, and perhaps disappear altogether. This is called evolution by natural selection: the frequencies of the three alleles have changed as a consequence of their reproductive effects. Over time, a population will acquire alleles that produce proteins that better solve critical reproductive problems, and lose alleles that produce proteins that less effectively solve these problems. There is widespread agreement that evolution by natural selection is responsible for the origins of the sophisticated organs and tissues like hearts, lung, livers, etc., that enable organisms to reproduce.
Because, in a population of a given size, the increase in the frequency of Tsuper must decrease the frequencies of the other alleles, biologists began saying that different alleles were ?competing?. (Usually, but not always, alleles increase their frequency by causing individuals possessing them to produce, on average, more offspring.) Dawkins, highlighting the iron-clad logic that alleles increase their frequency in the population if they cause more copies of themselves to be made relative to other alleles, and that by increasing their own frequency, they decrease the frequency of the alternative (competing) alleles, termed genes ?selfish?. Alleles increase their frequency at the expense of other alleles.
Hello ena that never got banned. It was a joke. Anyway, to business:
Quote:
Originally posted by ena
.
what did the intermidiate forms exist in?
long did this take?
Here's one possible solution.
"Smith postulates that this chemistry could have been facilitated by silica-rich minerals resembling zeolites, porous crystals with channels running through them. Most zeolites are hydrophilic--water-loving--and tend to absorb water from their surroundings. But certain synthetic zeolites are organophilic, preferentially absorbing organic materials out of water.
A naturally occurring organophilic zeolite--called mutinaite--was recently discovered in Antarctica, and Smith thinks that this mineral could provide the key to the chemical evolution that led to the origin of life. It's possible that mutinaite, which has aluminum in place of silica, loses aluminum at its surface to become silica-rich through weathering, Smith said. A small amount of remaining aluminum would provide the catalytic centers for assembling organic molecules into polymers."
Quote:
Originally posted by ena
you don't have any answers---you accept all of this on blind faith.
Oh, what nonsense. One explanation takes into account just about everything we know about anatomy, chemistry, and physics, and the other's magic. Like Obatala and his white sheet, only from the Middle East rather than West Africa.
Rational decision based on looking at probablity an' stuff.
Anyway, why is it bad when I make my decision on blind faith (which I don't) but perfectly OK when you do?
hassan has no reason to suspect that you do other than the copious quantities of evidence contained in your un-informative and parrot-like posts. in fact i believe hassan and even i could suspect that you are nothing more than an ai program, a very well designed one, but one that fails to provide answers because its knowledge base is limited. hurrah, computer programmer, you can turn off the machine.
that being said, i think hassan takes it on some blind faith [edit: ok maybe not] (with copious evidence) that i exist. and that is something that has to be even if we shake hands. we exist in our brains, the ballet before us could be but a nightmare.
i dont think anyone actually claimed that scientist dont at some point act on blind faith. why, if we discount evidence as anything, then every reaction that i set up is an act of blind faith. everytime i step outside, i am blindly faithful that the sun has risen.
haha, now i am deep.
i fail to see the relevence of this outside of an intro phil course or maybe high school philosophy. we all act on blind faith, it is the nature of anything that depends on previous occurances. perhaps those who failed to progress past the object permanence point in cognative development act only on what they see before them and dont act on blind faith, but i dont think those people live very long.
now, ena, if you arent a computer program, then you must understand that you are not adding anything to this discussion by saying repetedly you believe it on blind faith, because everything anyone does is dependent on blind faith.
now if you have some real suggestions on whether criticism of evolutionary theory be mandated in science classrooms, i am all ears, or eyes as it were.
Let's just stick to the facts---embryonic recapitulation has been debunked. (by evolutionists)
sorry by gills, i mean structures resembling both gentically and physically gills. and i will further grant you that not all embryo's look alike, that doesnt discount the fact that fetuses (human) have gill like structures.
Billybobsky, I refuse to believe you exist until I see a labelled 3D CG image of your DNA labelled 'Billybobsky's eyes', 'Billybobsky's brain', 'Billybobsky's skin colour', etc., and a complete 'road map' of you from conception to five minutes ago. With photographs.
And if ANY of it's missing, as much as ten minute's worth, I will consider you a fraud.
Billybobsky, I refuse to believe you exist until I see a labelled 3D CG image of your DNA labelled 'Billybobsky's eyes', 'Billybobsky's brain', 'Billybobsky's skin colour', etc., and a complete 'road map' of you from conception to five minutes ago. With photographs.
And if ANY of it's missing, as much as ten minute's worth, I will consider you a fraud.
Hello ena that never got banned. It was a joke. Anyway, to business:
Here's one possible solution.
"Smith postulates that this chemistry could have been facilitated by silica-rich minerals resembling zeolites, porous crystals with channels running through them. Most zeolites are hydrophilic--water-loving--and tend to absorb water from their surroundings. But certain synthetic zeolites are organophilic, preferentially absorbing organic materials out of water.
A naturally occurring organophilic zeolite--called mutinaite--was recently discovered in Antarctica, and Smith thinks that this mineral could provide the key to the chemical evolution that led to the origin of life. It's possible that mutinaite, which has aluminum in place of silica, loses aluminum at its surface to become silica-rich through weathering, Smith said. A small amount of remaining aluminum would provide the catalytic centers for assembling organic molecules into polymers."
Oh, what nonsense. One explanation takes into account just about everything we know about anatomy, chemistry, and physics, and the other's magic. Like Obatala and his white sheet, only from the Middle East rather than West Africa.
Rational decision based on looking at probablity an' stuff.
Anyway, why is it bad when I make my decision on blind faith (which I don't) but perfectly OK when you do?
Yes your blind faith is as good as anyone else's. Although, I don't think your average evolutionist realizes what a can of worms (s)he opens up until they start looking at the details of what they are asking.
Yes your blind faith is as good as anyone else's. Although, I don't think your average evolutionist realizes what a can of worms (s)he opens up until they start looking at the details of what they are asking.
when i read that i think "this is not a scientist, this is not a psuedoscientist, this is not an academic, this is not someone who respects academic integrity".
have you ever recieved a vaccine? do you know why its called a vaccine? it is because the latin for cow is vacca. the detractors of the initial vaccination called it such because the first vaccine (for small pox) involved injecting cow pox into people (mind you this was before a complete cell theory, let alone an understanding of viruses was around), and it was believed that the people would turn into cows. it is nonsense to tell a scientist that they dont know "what a can of worms (s)he opens" when they make a theory, present results to support it etc.
Yes your blind faith is as good as anyone else's. Although, I don't think your average evolutionist realizes what a can of worms (s)he opens up until they start looking at the details of what they are asking.
I don't think that many of the people arguing against evolution here--using the line of argument that because we cannot prove it, we ought to throw it out--realize that they would, if they followed the same line of reasoning in other matters, undo most of human history.
when i read that i think "this is not a scientist, this is not a psuedoscientist, this is not an academic, this is not someone who respects academic integrity".
have you ever recieved a vaccine? do you know why its called a vaccine? it is because the latin for cow is vacca. the detractors of the initial vaccination called it such because the first vaccine (for small pox) involved injecting cow pox into people (mind you this was before a complete cell theory, let alone an understanding of viruses was around), and it was believed that the people would turn into cows. it is nonsense to tell a scientist that they dont know "what a can of worms (s)he opens" when they make a theory, present results to support it etc.
I think I'll let you have it from here....I'm turning into a pumpkin.
And mandatory questioning of these theories and documented facts amounts to nothing more than mandatory discussion in the classroom that two plus two does in fact equal five. [/B]
Tonton,
I agree with you here, as I've said before, that it's crucial that these theories *are* questioned. The problem is that I don't think they ought to be questioned in a biology classroom.
Actually it does mean it could not have evolved in a series of simple steps.
When we take this outside of evolutionary debate it is much easier to understand. It is like the folks in future hardware that just ask why Apple doesn't just plug a Penium IV into their motherboards instead of a G4. You start with, well even if they suddenly found a way to make it pin compatible....etc.
I cannot really deal with the whole eye thing here because all the chemistry behind it really would be a couple chapters, not a couple pages.
Nick
So in a million years, when acheologists dig up a hot cup of coffee, they will marvel at its complexity and conclude it must have been created as found, because instant coffee is impossible?
I don't think so.
I have a friend who was born deaf. Why? Because of the particular mix of his parents genes. Are you suggesting that since life began, something like this has never happened before?
Comments
Originally posted by BRussell
This is what I don't get - how someone can believe in "micro-evolution" but not "macro-evolution." If species can change, as you acknowledge (I think), then how can longer time frames not produce larger changes? It seems to me that's like saying you believe that in 20 years water can form trenches but you don't believe that in a million it can form river beds.
Snipped that a bit to focus.
Your example is consistant but what I am talking about is not. Your example uses water twice, hence an existing trait.
I would for example believe that if we took two small hairy dogs and bred them together, we might get an even small hairier dog. We manipulate existing traits all the time, especially in agriculture.
However creating a new trait is entirely different. Your example would say that if in 20 years water can form trenches, but why don't I believe in 100 million years it can build a complex dam generating electricity.
The latter requires complexity, new materials, etc. That (for obvious reasons) is the leap I am not willing to make.
Evolution has been shown to help manipulate, in a gradual manner, existing traits. I have not seen proof of new abilities or traits though.
Nick
Originally posted by billybobsky
what does it mean?
(as a hint i will give you the definition from dictionary.com
biomechanics:
1. (used with a sing. verb) The study of the mechanics of a living body, especially of the forces exerted by muscles and gravity on the skeletal structure.
2. (used with a pl. verb) The mechanics of a part or function of a living body, such as of the heart or of locomotion.
)
you were using biochemical appropriately before, why the sudden switch to biomechanical which has very little to do with a molecule by molecule model of evolution.
i thought you would be (re)-banned by now
you're playing games and can't answer me---you don't have clue as to how amino acids formed to DNA-based lifeforms
...and I can't be re-banned if I haven't banned already.
I'm beginning to think brussle will have to settle for being my internet stalker, though. Apparently, if he can keep track of the boogie man he wont have to answer any hard questions. 'Looks like you're going for the same cheap thrills he is.
You should both be ashamed of yourselves.
Originally posted by ena
you're playing games and can't answer me---you don't have clue as to how amino acids formed to DNA-based lifeforms
...and I can't be re-banned if I haven't banned already.
I'm beginning to think brussle will have to settle for being my internet stalker, though. Apparently, if he can keep track of the boogie man he wont have to answer any hard questions. 'Looks like you're going for the same cheap thrills he is.
You should both be ashamed of yourselves.
do you know any science at all... i mean i need a starting point as far as discussing this any further. how far did you get in high school? or perhaps (though I am not sure of this) college? what science have you taken? how much of it do you trust? i need to know these things before i can discuss this issue with you because i wish not to waste words.
Originally posted by ena
you're playing games and can't answer me---you don't have clue as to how amino acids formed to DNA-based lifeforms
I'm a real spanner! DARWIN IS A WANKER, Jesus told me!
Aaanyway, amino acids. It's been a while since I boned up on proteins and evolutionary processes, so forgive me if I'm a bit rusty.
So... let's take the Markovian model of evolution which assumes that amino acids mutate independently of each other with probabilities which depend only on the amino acids and on the amount of evolution. In mathematical terms we can describe the model with mutation matrices: a mutation matrix, denoted by M, describes the probabilities of amino acid mutations for a given period of evolution:
Amino acids appear in nature with different frequencies. These frequencies are denoted by fi and correspond to the steady state of the Markov process defined by the matrix M, that is, the vector f is any of the columns of ? (M multiplied by itself an infinite number of times) or the eigenvector of M whose corresponding eigenvalue is 1 (M f = f). When we find a mutation in aligned sequences, we cannot distinguish which one mutated into which, or whether a third amino acid mutated into them. This implies a simple relation for the entries of M:
M describes mutations over a given period of evolution. We must quantify this amount of change in a mathematically meaningful way. Dayhoff et. al.[3] introduced the term PAM (point accepted mutation) unit.
Definition 1.1 _ A 1-PAM unit is the amount of evolution which will change, on average, ? of the amino acids. In mathematical terms, this is expressed as a matrix M such that ?
I'll post some more in a minute. I'm glad to be able to help you with your difficulties understanding ammino [sic] acids.
University of Chicago press release. 31 March 1988
How did life begin? Biochemical evolution on mineral surfaces
How did life begin on Earth? University of Chicago geophysicist Joseph V. Smith, in a Proceedings of the National Academy of Sciences paper published Tuesday, March 31, provides a theory for how small organic molecules may have been able to assemble on the surfaces of minerals into self-replicating biomolecules--the essential building blocks of life.
"The problem with most theories on the origin of life is that there is too much water around for the kind of organic chemistry that needed to take place," said Smith, Louis Block Professor in the Geophysical Sciences. "Synthesis of biomolecules from organic compounds dispersed in aqueous `soups' require a mechanism for concentrating the organic species next to each other, and biochemically significant polymers--like polypeptides and ribonucleic acids--must be protected from photochemical destruction by solar radiation."
Smith postulates that this chemistry could have been facilitated by silica-rich minerals resembling zeolites, porous crystals with channels running through them. Most zeolites are hydrophilic--water-loving--and tend to absorb water from their surroundings. But certain synthetic zeolites are organophilic, preferentially absorbing organic materials out of water.
A naturally occurring organophilic zeolite--called mutinaite--was recently discovered in Antarctica, and Smith thinks that this mineral could provide the key to the chemical evolution that led to the origin of life. It's possible that mutinaite, which has aluminum in place of silica, loses aluminum at its surface to become silica-rich through weathering, Smith said. A small amount of remaining aluminum would provide the catalytic centers for assembling organic molecules into polymers.
"For many years, I've wondered if such a material could occur in nature," said Smith. If small organic molecules, like amino acids, could accumulate in the pores of a zeolite, the mineral surface could have provided the catalytic framework for assembling them into polymers and protecting them from destruction by the sun.
A famous experiment performed at the University of Chicago in 1954 by then-graduate student Stanley Miller and his advisor, the Nobel laureate chemist Harold Urey, showed that amino acids, which make up the proteins found in all living organisms, could form from chemicals in the atmosphere combined with water and lightening.
[snip]
Amino acids occur naturally in right-handed and left-handed forms, but only the left-handed forms are found in the proteins of living organisms. Smith said, "It's probably an accident that only the left-handed form is used, but it may have started in a zeolite with a left-handed channel." Zeolites with one-dimensional channels could have provided the template for assembly of only one version of the amino acids into the first primitive proteins.
Smith plans a trip to Australia, where some of the oldest and least-metamorphosed rocks and minerals are found, to look for more naturally occurring organophilic zeolites like the mutinaite found in Antarctica. He's hoping these minerals still contain evidence of primary biocatalysis. Further research will include chemical experiments to see if the zeolites actually carry out the chemistry he proposes, and the use of computer models to study the structure of the channels.
Smith's work on zeolites was funded by Union Carbide Corporation/UOP, the National Science Foundation, the American Chemical Society, Exxon Educational Foundation, Mobil Research Foundation and Chevron Corporation.
Originally posted by trumptman
Evolution has been shown to help manipulate, in a gradual manner, existing traits. I have not seen proof of new abilities or traits though.
trumptman, I think i have your answer. Jaw bones are the result of a modified gill (fetuses and some new borns actually have gills), that much has been shown developmentally. Teeth are basically modified scales of the jaw bone, that also has been shown developmentally. Evolutionarily, it is suspected that gills developed from the vasculature that is seen in sponges and other sea dwelling species that dont have gills (this has not been proven), they then developed into jaws, and jaws became teeth, and teeth became tusks etc and who knows what. So to answer that question, and in reference to BRussell's post, small easily understood and realizable changes can when one occurs on top of the other produce two traits (gills and say tusks) that are apparently unrelated to eachother. If you grant that small changes can occur then it (in most cases) necessarily follows that significant changes can occur.
Originally posted by al-dajjal
I remember you. BRussell's very nice. He's no stalker, he's a proud father.
Aaanyway, amino acids. It's been a while since I boned up on proteins and evolutionary processes, so forgive me if I'm a bit rusty.
So... let's take the Markovian model of evolution which assumes that amino acids mutate independently of each other with probabilities which depend only on the amino acids and on the amount of evolution. In mathematical terms we can describe the model with mutation matrices: a mutation matrix, denoted by M, describes the probabilities of amino acid mutations for a given period of evolution:
Amino acids appear in nature with different frequencies. These frequencies are denoted by fi and correspond to the steady state of the Markov process defined by the matrix M, that is, the vector f is any of the columns of ? (M multiplied by itself an infinite number of times) or the eigenvector of M whose corresponding eigenvalue is 1 (M f = f). When we find a mutation in aligned sequences, we cannot distinguish which one mutated into which, or whether a third amino acid mutated into them. This implies a simple relation for the entries of M:
M describes mutations over a given period of evolution. We must quantify this amount of change in a mathematically meaningful way. Dayhoff et. al.[3] introduced the term PAM (point accepted mutation) unit.
Definition 1.1 _ A 1-PAM unit is the amount of evolution which will change, on average, ? of the amino acids. In mathematical terms, this is expressed as a matrix M such that ?
I'll post some more in a minute. I'm glad to be able to help you with your difficulties understanding ammino [sic] acids.
...very nice, but just as materialistic. You are just restating a theory with plenty of scientific phrasing. You aren't giving answers---you're bludgening the thread with technical jargon.
where is the roadmap: enitity to entity until we have DNA-based lifeforms?
what did the intermidiate forms exist in?
long did this take?
you don't have any answers---you accept all of this on blind faith.
Edward H. Hagen, Institute for Theoretical Biology, Berlin, quoth
Richard Dawkins wrote a very popular book called the Selfish Gene that explained, for a popular audience, many of the exciting new theories and discoveries being made in evolutionary biology in the 1960?s and 70?s. The metaphor Dawkins chose, the selfish gene, was an extremely powerful metaphor, so powerful that it has often overshadowed the science itself! The controversies that swirl around EP are often tightly bound up with Dawkins? metaphor. If our genes are selfish, are we all, deep down, unalterably selfish ourselves? Why did Dawkins chose this metaphor, what does it really mean, and what are its implications for EP and human nature?
Simplifying greatly for the sake of the argument, there is a molecule, called a nucleotide, that comes in four different types, A, C, G, & T. Large numbers of these nucleotides can be linked together in a linear strand to make a much bigger molecule called DNA. Schematically, DNA looks like this: ACGTGCCT?etc. Human DNA consists of about 3 billion nucleotides chained together. Simplifying greatly again, small sections of the DNA strand called ?genes?, which are usually several hundred to several thousand nucleotides long, are able to create a different type of long, linear molecule called a protein. Proteins are a kind of plastic?technically, a polymer?that, like the DNA chain, are made up of a small number of different molecular building blocks called amino acids (there are 20 different amino acid building blocks ). Just as the different chemical structure of the plastic in a plastic bag versus the chemical structure of the plastic in dental floss versus the chemical structure of the plastic in bullet-proof vests gives these different materials very different properties, the exact sequence of the different amino acids in a particular protein determines its biological properties. Different amino acid sequences give different proteins very different properties.
To summarize, the sequence of nucleotides in small sections of our DNA (called genes) determines the sequence of amino acids of proteins created by the genes, and these amino acid sequences determine the proteins? biological properties. Although scientists are still debating the exact number, DNA contains somewhere between 30,000 and 60,000 different genes, and can therefore create between 30,000 and 60,000 different proteins, each with unique properties. As I mentioned, proteins are a kind of plastic, so our DNA functions, in part, to create a large number of different plastics with different properties. These highly specialized plastics with very special biological properties are what our bodies are made of. DNA is a kind of lumber yard that provides, among other things, a large number of plastic building materials for making organisms.
Simplifying once more (this time by ignoring sex), individuals pass on an exact copy of their DNA chain to their offspring: if my body is made up of a particular set of plastics, because my offspring has an exact copy of my DNA, my offspring?s body will be make up of exactly the same set of plastics, and so it will be exactly like me. Occasionally, however, one of the molecules in the DNA chain (i.e., one of the A, C, G, or T nucleotides), can become mutated (altered) by cosmic radiation, environmental toxins, etc.; these mutagens turn one type of nucleotide into another type of nucleotide (e.g., an A turns into G). If I pass on this mutated DNA, where only one of the 3 billion nucleotides is different from my own, then my offspring will be made of proteins that are almost exactly like mine, except for the protein which was made by the mutated section of DNA (the mutated gene), which will be a different protein with different properties. My offspring will not be exactly like me?he will be said to have a different phenotype (body type).
Imagine that the gene that was mutated was the gene that made the plastic forming the lens of the eye. This plastic has a very special property: it is almost completely transparent. Most proteins, like those forming your skin, muscles, hair, etc., are not transparent. Because my offspring has a mutated form of the lens gene, there are now two types of genes in the population that make the lens protein: the normal version, possessed by most individuals (which I will call Tnormal, for normal transparency) and the mutated version possessed by my offspring. Different forms of the same gene are called alleles. Because it is far easier to make something worse than it is to make it better, most of the time when the gene producing the lens protein is mutated (and this happens very rarely), the altered lens protein produced by the mutated gene will not be as transparent as the original version (so I will label this allele Tlow, for low transparency). My offspring will therefore not be able to see as well as other members of his species who have the Tnormal allele, and thus normal versions of the lens protein.
Let?s assume that my offspring?s lens protein is only slightly less transparent than the normal version. He will be able to live his life and have offspring. The population will therefore contain a mix of lens alleles; most of the population will have Tnormal, but some will have Tlow. Because those with the Tlow allele will not be able to see quite as well as other members of their species possessing Tnormal, on average they will not have as many offspring. Perhaps they notice prey slightly less often, and thus not have quite as much food, or perhaps they fail to notice predators slightly more often, and will therefore be killed and eaten at a slightly higher frequency. Over many, many generations, the fraction of individuals with the Tlow allele will decrease relative to those with the Tnormal allele simply because individuals possessing the Tlow allele produce, on average, fewer offspring. We say that the Tlow allele producing the less transparent lens protein is selected against, and that the frequency of this allele decreases with time. Notice that, if the total population size remains constant, that the decrease in frequency of the Tlow allele results in an increase in the frequency of the Tnormal allele.
Imagine another mutation of the normal lens allele, creating a third allele (Tsuper) that produces a super transparent lens protein. The population now contains three alleles, Tlow, Tnormal, and Tsuper. Individuals possessing the Tsuper allele detect prey, on average, at slightly higher frequencies, and thus have more food, and they more frequently detect predators and therefore are eaten slightly less frequently. As a consequence, on average, they have more offspring than individuals possessing Tnormal. Over many, many generations, the frequency of the Tsuper allele will increase in the population, whereas the frequencies of the Tnormal and Tlow alleles will decrease, and perhaps disappear altogether. This is called evolution by natural selection: the frequencies of the three alleles have changed as a consequence of their reproductive effects. Over time, a population will acquire alleles that produce proteins that better solve critical reproductive problems, and lose alleles that produce proteins that less effectively solve these problems. There is widespread agreement that evolution by natural selection is responsible for the origins of the sophisticated organs and tissues like hearts, lung, livers, etc., that enable organisms to reproduce.
Because, in a population of a given size, the increase in the frequency of Tsuper must decrease the frequencies of the other alleles, biologists began saying that different alleles were ?competing?. (Usually, but not always, alleles increase their frequency by causing individuals possessing them to produce, on average, more offspring.) Dawkins, highlighting the iron-clad logic that alleles increase their frequency in the population if they cause more copies of themselves to be made relative to other alleles, and that by increasing their own frequency, they decrease the frequency of the alternative (competing) alleles, termed genes ?selfish?. Alleles increase their frequency at the expense of other alleles.
Copyright 1999-2002 Edward H. Hagen
_
Originally posted by billybobsky
(fetuses and some new borns actually have gills)
Let's just stick to the facts---embryonic recapitulation has been debunked. (by evolutionists)
Originally posted by ena
.
what did the intermidiate forms exist in?
long did this take?
Here's one possible solution.
"Smith postulates that this chemistry could have been facilitated by silica-rich minerals resembling zeolites, porous crystals with channels running through them. Most zeolites are hydrophilic--water-loving--and tend to absorb water from their surroundings. But certain synthetic zeolites are organophilic, preferentially absorbing organic materials out of water.
A naturally occurring organophilic zeolite--called mutinaite--was recently discovered in Antarctica, and Smith thinks that this mineral could provide the key to the chemical evolution that led to the origin of life. It's possible that mutinaite, which has aluminum in place of silica, loses aluminum at its surface to become silica-rich through weathering, Smith said. A small amount of remaining aluminum would provide the catalytic centers for assembling organic molecules into polymers."
Originally posted by ena
you don't have any answers---you accept all of this on blind faith.
Oh, what nonsense. One explanation takes into account just about everything we know about anatomy, chemistry, and physics, and the other's magic. Like Obatala and his white sheet, only from the Middle East rather than West Africa.
Rational decision based on looking at probablity an' stuff.
Anyway, why is it bad when I make my decision on blind faith (which I don't) but perfectly OK when you do?
hassan has no reason to suspect that you do other than the copious quantities of evidence contained in your un-informative and parrot-like posts. in fact i believe hassan and even i could suspect that you are nothing more than an ai program, a very well designed one, but one that fails to provide answers because its knowledge base is limited. hurrah, computer programmer, you can turn off the machine.
that being said, i think hassan takes it on some blind faith [edit: ok maybe not] (with copious evidence) that i exist. and that is something that has to be even if we shake hands. we exist in our brains, the ballet before us could be but a nightmare.
i dont think anyone actually claimed that scientist dont at some point act on blind faith. why, if we discount evidence as anything, then every reaction that i set up is an act of blind faith. everytime i step outside, i am blindly faithful that the sun has risen.
haha, now i am deep.
i fail to see the relevence of this outside of an intro phil course or maybe high school philosophy. we all act on blind faith, it is the nature of anything that depends on previous occurances. perhaps those who failed to progress past the object permanence point in cognative development act only on what they see before them and dont act on blind faith, but i dont think those people live very long.
now, ena, if you arent a computer program, then you must understand that you are not adding anything to this discussion by saying repetedly you believe it on blind faith, because everything anyone does is dependent on blind faith.
now if you have some real suggestions on whether criticism of evolutionary theory be mandated in science classrooms, i am all ears, or eyes as it were.
Originally posted by ena
Let's just stick to the facts---embryonic recapitulation has been debunked. (by evolutionists)
sorry by gills, i mean structures resembling both gentically and physically gills. and i will further grant you that not all embryo's look alike, that doesnt discount the fact that fetuses (human) have gill like structures.
And if ANY of it's missing, as much as ten minute's worth, I will consider you a fraud.
Originally posted by Hassan i Sabbah
Billybobsky, I refuse to believe you exist until I see a labelled 3D CG image of your DNA labelled 'Billybobsky's eyes', 'Billybobsky's brain', 'Billybobsky's skin colour', etc., and a complete 'road map' of you from conception to five minutes ago. With photographs.
And if ANY of it's missing, as much as ten minute's worth, I will consider you a fraud.
Originally posted by Hassan i Sabbah
Hello ena that never got banned. It was a joke. Anyway, to business:
Here's one possible solution.
"Smith postulates that this chemistry could have been facilitated by silica-rich minerals resembling zeolites, porous crystals with channels running through them. Most zeolites are hydrophilic--water-loving--and tend to absorb water from their surroundings. But certain synthetic zeolites are organophilic, preferentially absorbing organic materials out of water.
A naturally occurring organophilic zeolite--called mutinaite--was recently discovered in Antarctica, and Smith thinks that this mineral could provide the key to the chemical evolution that led to the origin of life. It's possible that mutinaite, which has aluminum in place of silica, loses aluminum at its surface to become silica-rich through weathering, Smith said. A small amount of remaining aluminum would provide the catalytic centers for assembling organic molecules into polymers."
Oh, what nonsense. One explanation takes into account just about everything we know about anatomy, chemistry, and physics, and the other's magic. Like Obatala and his white sheet, only from the Middle East rather than West Africa.
Rational decision based on looking at probablity an' stuff.
Anyway, why is it bad when I make my decision on blind faith (which I don't) but perfectly OK when you do?
Yes your blind faith is as good as anyone else's. Although, I don't think your average evolutionist realizes what a can of worms (s)he opens up until they start looking at the details of what they are asking.
Originally posted by ena
Yes your blind faith is as good as anyone else's. Although, I don't think your average evolutionist realizes what a can of worms (s)he opens up until they start looking at the details of what they are asking.
when i read that i think "this is not a scientist, this is not a psuedoscientist, this is not an academic, this is not someone who respects academic integrity".
have you ever recieved a vaccine? do you know why its called a vaccine? it is because the latin for cow is vacca. the detractors of the initial vaccination called it such because the first vaccine (for small pox) involved injecting cow pox into people (mind you this was before a complete cell theory, let alone an understanding of viruses was around), and it was believed that the people would turn into cows. it is nonsense to tell a scientist that they dont know "what a can of worms (s)he opens" when they make a theory, present results to support it etc.
Originally posted by ena
Yes your blind faith is as good as anyone else's. Although, I don't think your average evolutionist realizes what a can of worms (s)he opens up until they start looking at the details of what they are asking.
I don't think that many of the people arguing against evolution here--using the line of argument that because we cannot prove it, we ought to throw it out--realize that they would, if they followed the same line of reasoning in other matters, undo most of human history.
Cheers
Scott
Originally posted by billybobsky
when i read that i think "this is not a scientist, this is not a psuedoscientist, this is not an academic, this is not someone who respects academic integrity".
have you ever recieved a vaccine? do you know why its called a vaccine? it is because the latin for cow is vacca. the detractors of the initial vaccination called it such because the first vaccine (for small pox) involved injecting cow pox into people (mind you this was before a complete cell theory, let alone an understanding of viruses was around), and it was believed that the people would turn into cows. it is nonsense to tell a scientist that they dont know "what a can of worms (s)he opens" when they make a theory, present results to support it etc.
I think I'll let you have it from here....I'm turning into a pumpkin.
And mandatory questioning of these theories and documented facts amounts to nothing more than mandatory discussion in the classroom that two plus two does in fact equal five. [/B]
Tonton,
I agree with you here, as I've said before, that it's crucial that these theories *are* questioned. The problem is that I don't think they ought to be questioned in a biology classroom.
Cheers
Scott
Originally posted by trumptman
Actually it does mean it could not have evolved in a series of simple steps.
When we take this outside of evolutionary debate it is much easier to understand. It is like the folks in future hardware that just ask why Apple doesn't just plug a Penium IV into their motherboards instead of a G4. You start with, well even if they suddenly found a way to make it pin compatible....etc.
I cannot really deal with the whole eye thing here because all the chemistry behind it really would be a couple chapters, not a couple pages.
Nick
So in a million years, when acheologists dig up a hot cup of coffee, they will marvel at its complexity and conclude it must have been created as found, because instant coffee is impossible?
I don't think so.
I have a friend who was born deaf. Why? Because of the particular mix of his parents genes. Are you suggesting that since life began, something like this has never happened before?