Posted on 05/26/2012 9:47:00 PM PDT by eekitsagreek
Uh, yeah. And just what should a transitional species look like, if not the two species it's transitional between? This is one of the funniest objections yet.
I remember one person who used to participate in these threads had a chart of skulls along with their classification by various creationists. There was very little agreement on whether a particular skull was ape or human--some would say one, some the other. But they all agreed that no way could any of them be transitional between ape and human--oh no, that was impossible!
If you have ever watched an engineer work you will see them reuse solutions over and over again. You could line their work up and claim it auto-evolved with the same kinds of evidence.
And when the things engineers make start reproducing on their own, that argument might start to make sense.
It's clear that God could have designed every animal we have fossils of individually, reusing parts He liked for whatever reason. And He could have designed little horses and then changed His mind and replaced them all with big horses. Or He could have never made little horses at all, but rather just made little horse skeletons and buried them just to tease us. Pick your story. But the idea that that's "science," while the careful matching of rock ages with the fossils they contain and the alignment of morphological trees with phylogenetic analysis isn't, is "laughable on its face."
When you claim something is beyond debate then disagreeing with you is precisely what you are defining to be the problem.
The expression of traits has nothing to do with selection. It has everything to do with whether the individual has the genes for those traits or not.
Speaking of sexual reproduction, genes can exist in a population but not be expressed because 1) the proper combination happens too rarely to be noticed or 2) in the natural environment the combination results in the death of the individual organism. Change the environment or select for the specific gene and it will be expressed. No mutation needs to have occurred.
A trait that is not encoded in the DNA will never be expressed, because it is not there. No amount of selection will cause it to be there.
Unless you can conclusively prove that it is not encoded in the DNA of any individual in a population you haven't proved that it is not there.
If a new trait appears, it is because the DNA was altered somehow to make it appear. The most common alteration is a point mutation, but other, more drastic alterations can and do happen.
Not if you are talking about a combination of genes to produce the trait.
DNA undergoes constant mutation. In evolution, that matters when the mutation(s) occur in germ cells--the sperms and eggs. According to the biochemistry professor who wrote this blog, a human zygote has ~130 mutations. Most mutations, of course, are DNA errors that missed being repaired.
Some things are just absurd and should be considered more carefully. If those mutations are truly random they would be predominately negative and quickly result in the non-viability of humanity.
The minority of zygotes who live long enough and reproduce will pass ~half of their mutations to their offspring--along with the ~130 new germ cell mutations they pass along.
Might out to check that ratio of positive mutations to negative mutations again. And assuming the the negative mutations are adding up to positive mutations because we are still alive is another one of those show your homework moments.
One cannot "agree" or "disagree"; the only possibility here is to accept or reject the evidence.
What evidence? I see clearly delineated species that occurred relatively suddenly followed by changes that are best characterized by species dying off. I see a mountain of assumptions that dwarfs the data and understanding we do have. I see you sparing no effort to defend your beliefs and expending none to test your theories. Anyone who fails to mindlessly parrot the official line is branded a charlatan and shunned.
Settled science is dead science. Even the most basic core of science is subject to reconsideration: Newton gives way to Einstein. Not so with evolution. You don't discard the old theory, you redefine the new observations to fit it. For you the earth will always be the center of the universe because it is "beyond debate."
Your missing the point -- that it resembles two species proves nothing. It is just an observation. I have met several people who look like me, but are not related.
And when the things engineers make start reproducing on their own, that argument might start to make sense.
No, then evolution would make sense. The point is that similarity does not always boil down to heredity.
But the idea that that's "science," while the careful matching of rock ages with the fossils they contain and the alignment of morphological trees with phylogenetic analysis isn't, is "laughable on its face."
Attacking other people's religion is a poor argument for your "science."
When you claim something is beyond debate then disagreeing with you is precisely what you are defining to be the problem.
The basic mechanisms of genetics *are* settled. The basic mechanisms of DNA alteration *are* settled. The sciences of genetics and molecular biology, both of which are based in those mechanisms, moved beyond trying to establish that DNA mutates, or that DNA drives phenotype decades ago. You might as well try to debate whether photosynthesis in plants is a real phenomenon or not.
Speaking of sexual reproduction, genes can exist in a population but not be expressed because 1) the proper combination happens too rarely to be noticed or 2) in the natural environment the combination results in the death of the individual organism. Change the environment or select for the specific gene and it will be expressed. No mutation needs to have occurred.
A recessive gene that happens so rarely in a population that it is never seen is quite likely to disappear--it only has a 50% chance of being passed to offspring. In order for the effects of the gene to be seen, two individuals heterozygous for that gene have to mate and produce offspring, of whom 1/4 will express it. Selection is not a factor for a recessive gene that is never expressed. Selection cannot make an unexpressed gene suddenly express. Selection does not make two individuals carrying the same unexpressed gene find each other.
Selection would only be a factor if a rare gene is *not* recessive--in which case, it doesn't matter how rare the gene is in the population, it *will* have an effect on the individuals who have it. If the rare gene confers a survival advantage to those individuals carrying it, they are more likely to produce offspring than other individuals, and that gene may become more prevalent in the population. But--not always. Genetic drift--the accumulation of changes in gene frequency throughout a population is, for the most part, random.
Let's put it this way: the genetic traits for Down syndrome are not hidden until "selection" causes them to be expressed. Neither the mother nor the father of a Down syndrome child have Down genes. Down syndrome is caused when all or part of chromosome 21 is duplicated--a process that only occurs in the germ cell (the sperm or egg). Chromosome duplication is a common type of DNA mutation.
Let me reiterate: no amount of selection can cause a trait to appear if it is not encoded in the DNA. A new trait can only appear as a result of DNA alteration. Selective forces become relevant only after a new gene is expressed.
Unless you can conclusively prove that it is not encoded in the DNA of any individual in a population you haven't proved that it is not there.
I do not think it necessary to sequence the genome of every single human on the planet to conclude that we do not have genes to produce feathers. Nor do we have genes to produce an exoskeleton, pink hair, etc. I'm fairly certain that no amount of selective pressure is going to cause us to be able to digest wood, and that won't change--until an individual has a mutation in an enzyme gene that makes him/her able to digest wood, in which case selective pressure gives him/her a huge advantage for survival in a situation where food is scarce and wood is plentiful (otherwise, it's not an advantage, and there will be no selection).
Some things are just absurd and should be considered more carefully. If those mutations are truly random they would be predominately negative and quickly result in the non-viability of humanity.
Some things are just absurd and should be considered more carefully. If those mutations are truly random they would be predominately negative and quickly result in the non-viability of humanity.
You didn't read my last post carefully, did you? Mutations are absolutely random, and a large number of humans *do* die before their mothers even know they exist. Most mutations are not good or bad, but it does take only one bad one (out of the ~130 in the zygote) to be lethal. There is no need for a mutation to be beneficial to be passed on; as long as it is not lethal and the individual reproduces, any mutation has a chance of being maintained in the population.
I should also point out that DNA mutation isn't just a factor in reproduction. It can have a direct effect on your health. Cancers result from changes in gene expression...some of those changes are mutations, others are changes in DNA structure. And part of aging is that DNA changes in a very stereotypic and predictable fashion.
What evidence? I see clearly delineated species that occurred relatively suddenly followed by changes that are best characterized by species dying off. I see a mountain of assumptions that dwarfs the data and understanding we do have. I see you sparing no effort to defend your beliefs and expending none to test your theories. Anyone who fails to mindlessly parrot the official line is branded a charlatan and shunned.
Since when are species clearly delineated? What, exactly, are the "assumptions that dwarf the data"? I have yet to state a single opinion, assumption, or belief--everything I have said is backed up by mountains of scientific evidence. Does the fact that you don't want to actually read some of the (thousands of) scientific papers for yourself make those papers non-existent? Every Wikipedia article or webpage I have linked to has a ton of references. You can access and read those references for yourself. Those references have references, which you can also read. The references of references also have references--again, you have the right to read all of them. In the case of papers describing original research--you know, the process by which scientists painstakingly test hypotheses to establish the nature of reality--you are able to examine what the scientists did, what their hypothesis was, what their results were and how they interpret their results, and--if you really want--you can repeat their experiments for yourself and confirm their results. Or, if you don't want to repeat the experiments, you can find other papers written by scientists who repeated the experiments. We're way past trying to prove that DNA mutates (as if that were ever in doubt). We're way past trying to determine how it mutates. We're at the point where those processes are taken for granted, and we're trying to figure out the effect of X mutation on Y gene--a much more complicated proposition, because there are thousands of genes, and our level of knowledge about some genes is quite advanced, while we know nothing about others. And how do we determine the effect of mutation? We start out by purposely introducing mutations, and then we look at their effect. I did that all throughout graduate school.
Settled science is dead science. Even the most basic core of science is subject to reconsideration: Newton gives way to Einstein. Not so with evolution. You don't discard the old theory, you redefine the new observations to fit it. For you the earth will always be the center of the universe because it is "beyond debate."
That's exactly backwards. The current theory of evolution is quite different than that proposed by Darwin or any other scientist of his time or earlier. Remember, evolution is the process; the theory only describes the process. As we learn more about the process, we refine the theory. There is almost no legitimate scientist who doubts the fundamental process itself.
Why not just stick your fingers in your ears and hum?
You are just ignoring what I am saying and substituting your own strawman to argue against.
A recessive gene that happens so rarely in a population that it is never seen is quite likely to disappear--it only has a 50% chance of being passed to offspring.
Actually, there are quite a few rare but recurring genetic disorders that exist as recessive genes. Since the rare recessive genes that cause them are found in very different populations they have apparently been around a while.
I do not think it necessary to sequence the genome of every single human on the planet to conclude that we do not have genes to produce feathers.
If someone suddenly grew feathers I think we could be sure their DNA was tampered with purposefully, not that they were victims of a simple mutation.
On the other hand, if someone is born with a given rare trait you can't simply assume mutation until you demonstrate that their parents didn't have those genes.
Mutations are absolutely random, and a large number of humans *do* die before their mothers even know they exist.
According to your numbers, 1 out of 6 lives. It stands to reason then, that if 5/6 of those mutations are terminal, something like 5/6ths of the viable offspring have harmful mutations and half of those will be dominant. And they would be infinitely varied. Instead the same defects are the most common and occur in rates from 1 in 1000 to 1 in 10000.
Does the fact that you don't want to actually read some of the (thousands of) scientific papers for yourself make those papers non-existent? Every Wikipedia article or webpage I have linked to has a ton of references.
Detecting a pattern here -- every time I bring up an inconvenient excerpt from one of your citations, I am too uneducated to understand it. Anyone else who tries to elaborate outside of your control is "unscientific". And since when did Wikipedia attain the credibility of a scientific paper?
And nobody claims that, by itself, "proves" anything. It's evidence. Finding someone who looks a lot like you wouldn't prove you were related, but it'd be a valid reason to start comparing family trees and history.
The point is that similarity does not always boil down to heredity.
No. But sometimes it does. If your cousin looks like you, do you assume that a designer or engineer assembled you out of similar parts? Or do you conclude the similarity is inherited? Sometimes you have to use your common sense, even when you don't like what it tells you.
Attacking other people's religion is a poor argument for your "science."
I didn't attack anyone's religion. I just said it wasn't science.
You are just ignoring what I am saying and substituting your own strawman to argue against.
I have read every word that you wrote, and I still see that you have no grasp of science. BTW, just because I point that out does not mean I am "substituting my own strawman." Since making a strawman essentially consists of person A putting words into person B's mouth that B didn't actually say in order for A to argue against his/her own falsehood--I simply haven't done that. I have specifically answered what you actually said and tried to explain what is the actual case.
Actually, there are quite a few rare but recurring genetic disorders that exist as recessive genes. Since the rare recessive genes that cause them are found in very different populations they have apparently been around a while.
Not necessarily. When someone has a rare disorder that requires two defective copies of a gene, you don't know without analyzing their parent's DNA whether they got one defective copy from one parent who was a carrier and the other copy spontaneously mutated, both copies spontaneously mutated, or both parents were carriers. If the parents passed the defective gene to their child, it may be impossible to tell when that gene originally mutated; all you can know is that it mutated sometime in the past. Not all disorders are recessive; some are dominant, and some don't follow dominant/recessive patterns. A child who has a genetic disease caused by a non-recessive gene, and neither of whose parents have the mutation, has a de novo mutation.
If someone suddenly grew feathers I think we could be sure their DNA was tampered with purposefully, not that they were victims of a simple mutation.
On the other hand, if someone is born with a given rare trait you can't simply assume mutation until you demonstrate that their parents didn't have those genes.
If someone suddenly started sprouting feathers, I doubt I'd look at the DNA at all. I'd assume they were one of those freaks who go to extraordinary lengths to look like something other than ordinary human. If a baby were born with feathers, OTOH, I'd start looking at their genotype... and I wouldn't assume genetic manipulation until I could show that.
Unless a rare trait is purely recessive, you don't need to look at the parent's genes; if the child has a non-recessive trait that neither parent has, it's a de novo mutation. It happens quite a bit, actually.
According to your numbers, 1 out of 6 lives. It stands to reason then, that if 5/6 of those mutations are terminal, something like 5/6ths of the viable offspring have harmful mutations and half of those will be dominant. And they would be infinitely varied. Instead the same defects are the most common and occur in rates from 1 in 1000 to 1 in 10000.
Actually, it's more like 2/3 of all conceived humans don't live more than a few weeks into pregnancy. I never tried to calculate how many of the remaining third actually survive to reproduce (which is the only criterion that matters when speaking of evolution), but it's clear that we're doing just fine despite the high early death rate. It only takes one out of the ~130 mutations to be lethal; the majority of mutations are not lethal. They are not dominant, they are not recessive; most of them have little to no effect on phenotype and don't even occur in genes (either coding or regulatory regions).
Detecting a pattern here -- every time I bring up an inconvenient excerpt from one of your citations, I am too uneducated to understand it. Anyone else who tries to elaborate outside of your control is "unscientific". And since when did Wikipedia attain the credibility of a scientific paper?
You've brought up excerpts from some of my links that you completely misunderstood because you don't have the scientific training to understand what they were really saying, or what their context was, but you have yet to bring up an actual scientific excerpt that contradicts anything I've said. You also have never made a claim that you've backed up or even tried to support with any kind of reference to a scientific source.
I choose to link the Wikipedia articles, because I've found that they give pretty decent explanations that are, as far as I can tell, understandable to someone who doesn't have a PhD (or any science education, for that matter). I scan the articles to make sure the information they present is accurate, without glaring errors. Then I look over the references to see how many there are (every fact mentioned in a scientific article must be supported by at least one reference), and what the quality of them is (only journals and scientific books are reliable). Linking the Wiki articles also saves me from having to dig up a reference for every single thing I say, because the authors of those Wiki entries already did all the reference hunting. The Wiki articles aren't scientific papers; if I linked to those, no one but me and maybe a handful of other FReepers would be able to understand them. But they are very good for a layperson who wants to learn more about the subject, plus anyone is free to look up the references and read them. I do this kind of vetting process for everything that I link.
In my professional career, whenever I want to find out more about a subject that is unfamiliar to me, I often read the Wikipedia article as a place to start. *Then* I start searching the scientific literature.
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