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The Origin of Specious Nonsense. Twelve years on. Still going. Answer soon.
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What is tiresome is your complete lack of comprehension of the distinction between biologiocal evolution as a scientific fact and the various theories describing the mechanisms of biological evolution. I am done trying to educate you on the distinction, read the article I posted above by Larry Moran and educate yourself.
You have repeatably dodged responding to the points in my rebuttal and just repeated the same thing over and over. I'm assuming you didn't think you would have to follow up your statements with actual logic and reason.
Wouldn't be the first time we have run into that problem, would it nagirrac?0 -
You have repeatably dodged responding to the points in my rebuttal and just repeated the same thing over and over. I'm assuming you didn't think you would have to follow up your statements with actual logic and reason.
Wouldn't be the first time we have run into that problem, would it nagirrac?
A sure sign you have lost the argument when you have to personalize the discussion.
My logic and reasoning in terms of what evolution is and the distinction between evolution as a fact and the various theories of evolution are completely in agreement with science. I have no idea where your logic and reasoning is coming from but it is not science.0 -
A sure sign you have lost the argument when you have to personalize the discussion.
No, its a sure sign that I'm sick and tired of your debating tactic, of never dealing with rebuttals put to you, but just moving on to the next round of nonsense.
I'm still waiting for you evidence that consciousness controls matter, or that evolution is creative and intelligent ... but I suppose it is easier just to move on to the next bit of hookum, or if really pushed into a corner just say its your "world view" ... this is the most anti-scientific nonsense since JC (the Creationist troll) frequented these partsMy logic and reasoning in terms of what evolution is and the distinction between evolution as a fact and the various theories of evolution are completely in agreement with science. I have no idea where your logic and reasoning is coming from but it is not science.
And the 5 times I've presented my rebuttal?
If a cat gave birth to a dog would that be evolution? You ignored that the first time around ...0 -
If a cat gave birth to a dog would that be evolution? You ignored that the first time around ...
..because it is genuinely hard to respond to absurd rebuttals.
If a cat gave birth to a dog it would be evidence against everything we know about biological evolution (for 150 years, if not 250 years, if not 2,000 years and did not just call it "evolution") and we would regard that event as "supernatural".
We may still have a long way to go in understanding the mechanisms (theory) of how evolution (fact) occurred, but we do know that an individual from one sexually reproducing species does not give birth to a different species. Naturalists did not need genetics to figure that out.0 -
That is precisely the point, the rock is changing but the change is not evolutionary.
Which is why it is incorrect to say evolution is just change and change is evolution. Evolution is a particular type of change.)
Change is change - accumulated change in living things is evolution.Imagine that if instead of Darwinian evolution, which is how we know life evolves, instead life changed as the rock in the river does, just stuff happening here and there with no selection process.
Would life evolve without this selection process? Would life evolve if it was like the rock in the stream, and stuff just happened to it to change it but there were no other mechanics taking place (ie no natural selection process)?
But stuff does just happen here and there, it's just that the helpfull stuff is more likely to be passed on due to the organisms survival. If a cheetah is born with a genetic difference that means it can only run at half the speed of other cheetahs, odds are it will starve and that gene will die out. If it's born with a gene that speeds it up, odds are it will thrive and pass the gene on. That's the "selection process". Surely it's more of a by product than a driving force - the changes aren't "driven" per se, it just so happens that the good ones tend to stick around due to having a reproductive advantage.
Maybe i'm taking you up wrong but you seem to be suggesting that evolution strives to help living things survive, which as far as i can see it doesn't. It has no intent either good or bad, it's just an uncaring stream of change - the changes that happen to help survival - lead to survival (survival of the fittest). But equally, millions of species have evolved themselves into extinction.0 -
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sbsquarepants wrote: »Maybe i'm taking you up wrong but you seem to be suggesting that evolution strives to help living things survive, which as far as i can see it doesn't.
My point was that we cannot know evolution is taking place divorced of all Darwinian and Neo-Darwinian understanding of the mechanisms that drive it, which is what nagirrac is suggestion, so he can drop his own "creative intelligent" mechanism in and pretend that he is still adhering to sound scientific reasoning. Understanding of Darwinian and Neo-Darwinian evolution is what allows us to say that evolution is taking place in the first place.0 -
Am I the only one who thinks the title for this new thread is a little flirty sounding?
Like the ads for the sexlines on late night tv?
"Call now for evolution, creationism... and maybe more"0 -
..because it is genuinely hard to respond to absurd rebuttals.
If a cat gave birth to a dog it would be evidence against everything we know about biological evolution (for 150 years, if not 250 years, if not 2,000 years and did not just call it "evolution") and we would regard that event as "supernatural".
Precisely. And this non-evolutionary event would still fit with in your definition of what evolution is if you take that definition in isolation, which I suspect it never was meant to be taken.
So how can that definition be what evolution is when it encompasses things that are clearly not evolutionary?
This is the rebuttal that you have refused to address.We may still have a long way to go in understanding the mechanisms (theory) of how evolution (fact) occurred
No, we really don't. You would like that to be the case so your ridiculous notions can live in these gaps, but in reality these gaps are very small. Biologists are discovering the precise details of the mechanics of evolution, not still trying to decide what is the over arching mechanics in the first place. Your analogy to gravity and the mechanics of gravity is way off. The idea that we know evolution takes place but Neo-Darwinian evolution is just one possible explanation among many is frankly utter nonsense.
When people say evolution is a established they mean Neo-Darwinian evolution is a established. There are no other plausible theories of evolution, certainly not "creative intelligent" or what ever the heck that was.0 -
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It's a classic tease. There's never more.0
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More on your phone bill, perhaps. :pac:0
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Precisely. And this non-evolutionary event would still fit with in your definition of what evolution is if you take that definition in isolation, which I suspect it never was meant to be taken.
So how can that definition be what evolution is when it encompasses things that are clearly not evolutionary?
This is the rebuttal that you have refused to address.
When people say evolution is established they mean Neo-Darwinian evolution is a established. There are no other plausible theories of evolution, certainly not "creative intelligent" or what ever the heck that was.
First of all it's not my definition of evolution, it's the definition of evolution you will find from every scientific source, a university biology department for example. The only place you will find your definition (we only know evolution occurs because of the mechanism) is on atheist websites, but I will get back to that later.
A cat giving birth to a dog does not fit into the definition. What is it about the term "inheritable characteristics" that you can't seem to grasp. Naturalists had been studying both living lifeforms and fossils for centuries before Darwin, it was clearly understood what was inheritable and not inheritable. Again, getting back to my basic point, why would evolution have been accepted within the scientific community as a fact before genetics was even discovered and applied to the theory of evolution? The answer is because there was overwhelming evidence for it before any mechanism was proposed (just as there is overwhelming evidence for gravity without an agreed mechanism).
The reason why atheists focus so much on the mechanism of evolution is because it fits nicely with their worldview of a random, purposeless universe. Because of the underlying mechanism (random mutation), then the universe must be random, ergo atheism. It is completely flawed logic and inserts the question of belief or non-belief in God into science where it does not belong. In many ways atheists are as bad as creationists in this regard.
Obviously your whole issue here is my use of the term "creative intelligence". This is called speculation zombrex, the root of all scientific inquiry. Science starts with a guess, then works its way up to a hypothesis, then a theory and then a fact.
Your statement on where science is at (just filling in the litttle details) in understanding evolution is as laughably naive as Lord Kelvin's infamous remark stating there was nothing new to be discovered in physics, just a matter of filling in the details. Its a pity he didn't live another decade and have to try and absorb the theories of relativity and quantum physics.
We are only starting on the journey to understanding the DNA molecule. The human genome was only decoded a decade ago. When we understand in more detail how DNA functions we will then know a lot more about how life evolved. Let me outline one of the many challenges for you, the development of the human brain, and perhaps it will pose some questions for you.
During human fetal development the development of the brain accelerates at an incredibble level, in the last month of development new brain cells are made and placed in their precise structure at the rate of 250,000 per second. At birth, the human brain has a trillion neurons with an average of a thousand synaptic connections per neuron, for a total of 1,000,000,000,000 connections. There are hundreds of different types of neurons utilizing thousands of different proteins in the human brain. This amazing structure is then trimmed to 100 billion neurons during childhood development, in a variety of stages leading to what we know of as an adult brain.
All of this development arises from a single DNA molecule in a single cell (the egg and sperm cells being essentially the same from a DNA perspective). The mechanism for how this unfolds is highly mysterious to science, we are just starting to scratch the surface in understanding it. Literally every step we take in understanding brain function unearths another group of mysteries.
Everywhere we look in nature we find intelligence, learned behavior that is passed on in DNA. Did you know that rats have the same ability as humans to reflect on their own thoughts? that flies sleep, and express the same genes in asleep and awake states as we do? Clearly such abilities are not related to brain size.
DNA is the driving force of evolution, we simply cannot say we understand the mechanisms of evolution well when we are only starting to understand how DNA functions. It may well be (speculation again, sorry) that DNA is a highly adaptive molecule. This is the whole debate on whether the vast amounts of non coding DNA have a functional, adaptive role or are simply "junk". Are Transposable Elements (TEs) parasitic, the selfish gene hypothesis of Dawkins, or are they functional? That is the big question, and that is the precise area where I believe we will uncover more knowledge regarding evolutionary mechanisms.0 -
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A cat giving birth to a dog does not fit into the definition. What is it about the term "inheritable characteristics" that you can't seem to grasp.
I've already asked you this, but lets try again. If a cat gave birth to a dog why would you say that wasn't iheritable characteristics.
Try answering that question without referencing anything in Neo-Darwinian evolution, and you might grasp the point.Again, getting back to my basic point, why would evolution have been accepted within the scientific community as a fact before genetics was even discovered and applied to the theory of evolution? The answer is because there was overwhelming evidence for it before any mechanism was proposed (just as there is overwhelming evidence for gravity without an agreed mechanism).
Evolution was accepted as a fact because Darwin provided the mechanics that explained it.The reason why atheists focus so much on the mechanism of evolution is because it fits nicely with their worldview of a random, purposeless universe. Because of the underlying mechanism (random mutation), then the universe must be random, ergo atheism. It is completely flawed logic and inserts the question of belief or non-belief in God into science where it does not belong. In many ways atheists are as bad as creationists in this regard.
Here we go :rolleyes:
There were atheists around long before anyone knew anything about mutation nagirrac. I was an atheist long before I knew anything about mutation.
All you need to be an atheist is to reject the claims of theists, and that isn't hard, you can do that without knowing anything about evolution.Obviously your whole issue here is my use of the term "creative intelligence". This is called speculation zombrex, the root of all scientific inquiry. Science starts with a guess, then works its way up to a hypothesis, then a theory and then a fact.
Yes, and it isn't science if you just stop at the guess part.
People who believe their guesses without processing to the hypothesis, theory and fact parts, are not scientists. Far from it in fact.We are only starting on the journey to understanding the DNA molecule. The human genome was only decoded a decade ago. When we understand in more detail how DNA functions we will then know a lot more about how life evolved.
These are details within the Neo-Darwinian frame work, they are not some smoking gun that some how will prove the whole universe is intelligently creating itself or what ever nonsense you believe in.
Stop this God of the gaps nonsense nagirrac. You criticise science but then retreat to worshiping your guesses.Everywhere we look in nature we find intelligence, learned behavior that is passed on in DNA.
Hog wash. We don't find that anywhere. Nothing learned is passed on in DNA.
If we did you could give me more than "its my guess" as an answer. :rolleyes:0 -
I'm coming late to the current argument, so apologies if this has already been said.
It seems to me that most biologists take the 'fact' of evolution to mean that it is solidly established that species have evolved from earlier species, and that all life has common ancestry. That is what I get from most of the quotes in Nagirrac's link from talk origins. 20+ years on from those quotes, that is truer than ever.
What is still somewhat undecided, as Nagirrac's quotes also say, is exactly how evolution is happening: how much of genome sequence evolution is neutral and how much is adaptive, and how speciation occurs. On the neutral vs adaptive question at least, we have amassed lot more data in the last 20+ years. The picture is that both processes are ongoing at the sequence level, with Darwinian 'positive' selection playing a major role in shaping phenotype. I've a mostly-written longer post on this with citations, but I'll hold fire unless it becomes more relevant.0 -
darjeeling wrote: »I'm coming late to the current argument, so apologies if this has already been said.
It seems to me that most biologists take the 'fact' of evolution to mean that it is solidly established that species have evolved from earlier species, and that all life has common ancestry. That is what I get from most of the quotes in Nagirrac's link from talk origins. 20+ years on from those quotes, that is truer than ever.
What is still somewhat undecided, as Nagirrac's quotes also say, is exactly how evolution is happening: how much of genome sequence evolution is neutral and how much is adaptive, and how speciation occurs. On the neutral vs adaptive question at least, we have amassed lot more data in the last 20+ years. The picture is that both processes are ongoing at the sequence level, with Darwinian 'positive' selection playing a major role in shaping phenotype. I've a mostly-written longer post on this with citations, but I'll hold fire unless it becomes more relevant.
Be careful with the bit in bold. The emphasis should be on the exactly bit, because without that being clear (biologists are looking for the exact details of how evolution works within the Neo-Darwinian framework already established), it leaves the door open for the nonsense nagirrac is talking about, where we throw Darwinian evolution out the window and start talking about "creative intelligence" and "learned behavior" guiding evolution.
nagirrac is a non-theistic creationist, a new age snake oil peddler. I wouldn't give him the opportunity to believe that his beliefs some how have validity because biologists haven't figured out ever last aspect of how evolution works.0 -
I've already asked you this, but lets try again. If a cat gave birth to a dog why would you say that wasn't iheritable characteristics.
Evolution was accepted as a fact because Darwin provided the mechanics that explained it.
There were atheists around long before anyone knew anything about mutation nagirrac. I was an atheist long before I knew anything about mutation.
Hog wash. We don't find that anywhere. Nothing learned is passed on in DNA.
I'm not sure I've ever encountered such a rash of misconceptions and fallacies in one post on any internet forum:( (and I've only selected the worst ones):
The cat giving birth to the dog: I don't have to reference anything in Darwinian, neo-Darwinian or modern synthesis thought. Species do not give birth to other species, you can observe this yourself if you spend enough time in nature. From observing nature you learn what is "inheritable" and "not inheritable", with no understanding of what mechanism is behind inheritance. Unfortunately for your position, naturalists understood this long before Darwin.
Evolution was established as a scientific fact by Darwin, building on the work before him by hundreds of naturalists, by providing overwhelming evidence for evolution (form and function simularities, fossil record, etc). Nothing to do with the mechanism. Have you read "On the origin of species?" Your failure to understand this distinction puts you out of step with every scientist on the planet. It is however a common non-scientist misconception.
I am not suggesting the theory of evolution has a cause and effect relationship with atheism, and the fact you think I am indicates you have a serious comprehension problem. I am suggesting how an atheist looks at evolution, and you are making my point for me. For an example of how a scientist with no belief/lack of belief bias looks at evolution ponder the response given by Francis Collins, head of the NIH, when asked whether he believed life was designed.. he answered: "it could be". That is the correct scientific answer, not one biased by a belief in God (creationists) or belief in a random, purposeless universe (atheists).
Behavior is inherited, we call it instinct. How does a chicken raised from day old with no interation with older chickens know how to roost? Have a look at the studies done on behavioral problems in kids raised by biological parents and those adopted, including identical twins. You should really read up on this because it is one of the more interesting areas in science, spanning many disciplines including neuroscience and genetics. The correct scientific answer you will get as to how behavior is inherited is "we don't know currently". The most common "guess" you will get is behavior or instinct is "hardwired into the brain". How is the brain wired?.. by DNA. That's why I gave you the example of brain development as an example of a challenge in understanding the functions of DNA, but (unsurprisingly) it has gone completely over your head.
I have never introduced God into this discussion but you continue to do so, highlighting the preoccupation atheists have with God.0 -
nagirrac is a non-theistic creationist, a new age snake oil peddler. I wouldn't give him the opportunity to believe that his beliefs some how have validity because biologists haven't figured out ever last aspect of how evolution works.
As expected, now that you have had your ass handed to you by someone who knows more about evolutionary biology than you or I know or may ever know, you resort to personal insults.0 -
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Be careful with the bit in bold. The emphasis should be on the exactly bit, because without that being clear (biologists are looking for the exact details of how evolution works within the Neo-Darwinian framework already established), it leaves the door open for the nonsense nagirrac is talking about, where we throw Darwinian evolution out the window and start talking about "creative intelligence" and "learned behavior" guiding evolution.
I'm aware of that. I've seen genetic drift, transposons, transgenerational epigenetic inheritance, selection, functionality, junk DNA - all kinds of things being brought up, with suggestions that these point to an inherent intelligence in evolution. The evolutionary questions I'm talking about - genetic drift vs adaptation, ecological and demographic parameters in speciation - have nothing to do with any such intelligence, for which I see no evidence.0 -
As expected, now that you have had your ass handed to you by someone who knows more about evolutionary biology than you or I know or may ever know, you resort to personal insults.
I don't think I'm doing that - I just said how I see things, and didn't refer directly to previous comments in thread.
Also, I would never claim to be any great authority - that's why I like to cite when I have time so that people can see for themselves if what I'm saying is true.0 -
darjeeling wrote: »I don't think I'm doing that - I just said how I see things, and didn't refer directly to previous comments in thread.
Also, I would never claim to be any great authority - that's why I like to cite when I have time so that people can see for themselves if what I'm saying is true.
Agreed, that is my conclusion.
However, your interpretation of the "fact" versus "mechanisms" of evolution debate is in keeping with what I have said for about 20 posts and which zombrex has been arguing against.
Do you agree that we still have a long way to go in understanding how DNA functions, for example the development of the human brain?0 -
Do you agree that we still have a long way to go in understanding how DNA functions, for example the development of the human brain?
I really don't know enough about neuroscience to comment very meaningfully, as I'm not very familiar with how genes contribute to building a brain. TCD's Kevin Mitchell is interested in this and has a blog worth a follow.
Evolutionarily, I've read that several genes involved in controlling brain development, size and neurotransmission seem to have been under recent Darwinian 'positive' selection (i.e. selection to increase frequency of an advantageous mutation) in humans in the last tens of thousands of years (links: 1, 2, 3). This does point to the importance of adaptive changes in the brain in shaping recent human evolution.0 -
The cat giving birth to the dog: I don't have to reference anything in Darwinian, neo-Darwinian or modern synthesis thought. Species do not give birth to other species, you can observe this yourself if you spend enough time in nature. From observing nature you learn what is "inheritable" and "not inheritable", with no understanding of what mechanism is behind inheritance. Unfortunately for your position, naturalists understood this long before Darwin.
You are still purposefully avoiding my point.
Given that a cat giving birth to a dog would fit your definition of evolution, how is your definition sound? (I say your definition because you are using it devoid of any Darwinian context, which is not what the original authors would have meant)Evolution was established as a scientific fact by Darwin, building on the work before him by hundreds of naturalists, by providing overwhelming evidence for evolution (form and function simularities, fossil record, etc). Nothing to do with the mechanism.
You cannot be serious :rolleyes: It is called Darwinism for a reason.I am not suggesting the theory of evolution has a cause and effect relationship with atheism, and the fact you think I am indicates you have a serious comprehension problem. I am suggesting how an atheist looks at evolution, and you are making my point for me. For an example of how a scientist with no belief/lack of belief bias looks at evolution ponder the response given by Francis Collins, head of the NIH, when asked whether he believed life was designed.. he answered: "it could be". That is the correct scientific answer, not one biased by a belief in God (creationists) or belief in a random, purposeless universe (atheists).
"It could be" is an answer for anything. Are well all brains in jars? We could be.
Science is interested what is, not what could be.Behavior is inherited, we call it instinct.I have never introduced God into this discussion but you continue to do so, highlighting the preoccupation atheists have with God.
You have introduced a host of nonsense concepts, that have been rebutted every time you have. The best you can come up with is that this is your "guess" or your "world view"
As expected when pressed you retreat from any solid evidence, facts or theories and just waffle on about what could be and what you personally believe.0 -
Behavior does not impact DNA. It is a one way process. Nothing learned is passed on through DNA.
As expected when pressed you retreat from any solid evidence, facts or theories and just waffle on about what could be and what you personally believe.
I gave you a thanks because you are hanging on to your dogma admirably, much like Mick Rock.
Do you honestly believe there is no such thing as genetically transmitted behavioral traits? If you do not believe it, I have a few dogs (one of them is even psychic:)) I would like to introduce you to. Behaviors are breed specific in domestic dogs. There was study done examining retrieval desire in dogs, you know whether they would run after a stick and bring it back. Chasing after it may be instinctive but bringing it back is a learned trait and it is also inherited. Certain retriever breeds have 95% retrieval and return data while other retriever breeds have 50%. Some domestic breeds have literally none.
Certain behaviors are hardwired into the brain and transmitted through generations, while others are learned during development. You need to accept the fact of genetically transmitted behavioral traits. Most behavioral biologists recognize that all behavior is a blend of learned, inherited and modifiable. If it is inherited how does this not involve DNA? I expect you'll say that's genetics and not evolution, but of course its evolution, just artificial selection evolution.0 -
I gave you a thanks because you are hanging on to your dogma admirably, much like Mick Rock.
Do you honestly believe there is no such thing as genetically transmitted behavioral traits? If you do not believe it, I have a few dogs (one of them is even psychic:)) I would like to introduce you to. Behaviors are breed specific in domestic dogs. There was study done examining retrieval desire in dogs, you know whether they would run after a stick and bring it back. Chasing after it may be instinctive but bringing it back is a learned trait and it is also inherited. Certain retriever breeds have 95% retrieval and return data while other retriever breeds have 50%. Some domestic breeds have literally none.
Certain behaviors are hardwired into the brain and transmitted through generations, while others are learned during development. You need to accept the fact of genetically transmitted behavioral traits. Most behavioral biologists recognize that all behavior is a blend of learned, inherited and modifiable. If it is inherited how does this not involve DNA? I expect you'll say that's genetics and not evolution, but of course its evolution, just artificial selection evolution.
Wooh hold on a second there...
Yes there are in genetically transmitted behavioural traits but learned behaviours are not recored and stored on a gentic level.
Could you cite some of these biologists that think that learned traits are inheritable?0 -
I gave you a thanks because you are hanging on to your dogma admirably, much like Mick Rock.
Do you honestly believe there is no such thing as genetically transmitted behavioral traits? If you do not believe it, I have a few dogs (one of them is even psychic:)) I would like to introduce you to. Behaviors are breed specific in domestic dogs. There was study done examining retrieval desire in dogs, you know whether they would run after a stick and bring it back. Chasing after it may be instinctive but bringing it back is a learned trait and it is also inherited. Certain retriever breeds have 95% retrieval and return data while other retriever breeds have 50%. Some domestic breeds have literally none.
Certain behaviors are hardwired into the brain and transmitted through generations, while others are learned during development. You need to accept the fact of genetically transmitted behavioral traits. Most behavioral biologists recognize that all behavior is a blend of learned, inherited and modifiable. If it is inherited how does this not involve DNA? I expect you'll say that's genetics and not evolution, but of course its evolution, just artificial selection evolution.
I've no problem with instinct being transmitted via DNA. But then we both know that isn't what you claimed.
You claimed that learned behavior is passed on in DNA.Everywhere we look in nature we find intelligence, learned behavior that is passed on in DNA
This was part of your evolution is intelligent/creative nonsense. I appreciate you are now back tracking, but I can only go on what you state ...0 -
Wooh hold on a second there...
Yes there are in genetically transmitted behavioural traits but learned behaviours are not recored and stored on a gentic level.
Could you cite some of these biologists that think that learned traits are inheritable?
I fully accept that this is not well understood in terms of the mechanism. There is no science to cite because as yet the mechanism is not understood. However, evolutionary biologists, from what I have read, seem agreed that behavior is a mixture of inherited, learned in early development (due to environment) and modifiable. All three involve wiring the brain, and the only thing that can wire the brain is DNA. The unknown is the mechanism.
I fully understand the objection here, that the agreed mechanism in genetics currently has no place for events that happen during the lifetime of the organism in terms of phenome development that can impact the genome in terms of inherited characteristics. What I am saying is based on what we observe there must be a mechanism.
There are many observed inheritance traits we have no mechanism for. We know for certain many mental illness conditions are inherited (like schizophrenia), but we have no mechanism for how it happens. If you go on the blog that darjeeling referenced a few posts up you will see very lively debate on this topic.
The main point I am making is that because something is observed in nature or in evolution does not mean we have a mechanism to explain it, but the only possible mechanism is in DNA because that is the only molecule involved in inheritance.
What is instinct if it isn't learned behavior at some point in the organism's evolution? Think about dog breeding. A dog running after a falling pheasant or a stick may be called instinctive, but there are many dog breeds who will not run after anything. A dog that runs after something, fetches it and returns it is behavior that was bred into the dog. The same with chickens roosting. It's easy to say "instinct" but not so easy to explain the mechanism. Clearly at some point in their evolution the behavior of roosting became hardwired into a domestic chicken's brain structure and this behavior is inherited. Yes, you can say from a natural selection standpoint chickens who did not roost all got eaten eventually and only the one's who roost survived to reproduce.. but what is the mechanism? Is there an allene for roosting, for stick fetching?0 -
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The main point I am making is that because something is observed in nature or in evolution does not mean we have a mechanism to explain it, but the only possible mechanism is in DNA because that is the only molecule involved in inheritance.
And as you have mentioned previously, we have some tentative and worth-pursuing hints that it may not only be the As,Cs,Gs and Ts of the sequence, but the epigenetic modifications to this sequence that can be inherited, at least for a few generations.
Kevin Mitchell says in his blog that he is skeptical that epigenetic inheritance has much of a role in determining behaviour, because of a lot of experimental groundwork that has led us to think that epigenetic modifications are wiped clean in the early embryo, and then reinstated as cells diverge and become different tissues. Also, the fact that germ cells are insulated from most epigenetic change happening elsewhere during the life of the organism.
The best evidence for inherited epigenetic behavioural changes seems to be the Swedish chicken study, which claims to have found results at odds with Mitchell's view. I haven't fully read the paper yet, but mean to when I get time.0
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