Global Warning/Climate Change

[Josh]

If you want to make your name in science, come up with a discovery that re-writes or overturns some existing understanding or theory, not some discovery that merely confirms what we already know or think that we know. Nothing will give a young scientist more instant fame and fortune than proving his or her elders were wrong. Galileo, Einstein, Newton, Copernicus, Pasteur, Darwin, etc. were all famous for upsetting the existing body of science, not confirming it.

come to think of it, that's exactly what Jesus did. He's famous for upsetting the existing body of religion, not confirming it.

Yes, people tend to forget that he was very much a radical and revolutionary. I wonder if many Christians would recognize him he if returned to walk among us today.

We would, because God is the same yesterday, today, and forever, and in fact Jesus does walk amongst us today and still has the same message.

You can find that message in the Bible.

[Josh]

This is actually not true. Scientific ideas do not mature from hypotheses to become theories and then finally graduate to become laws. In science, laws and theories are two completely different things:

No, that actually is true. I’m not sure why you are arguing about this.

[Josh]

Yes. I'm not actually super in tune with all the latest research in this area.

In that case, perhaps it would be best to not be lecturing and correcting other posters.

[Ken]

Perhaps in normal scenarios but that is ignoring retroviruses and transcriptase.

Well yes. It is really more along the lines of, you can't spend your life training yourself to be super fast, super strong, or super fit, and then pass those traits on to your offspring. What you pass on to your offspring are the genes that you were born with, not traits that you might have developed since then.

The study of epigenetics shows this is not actually the case. For example, people who are drinking during pregnancy are more likely to have children who grow up to be alcoholics. The same mother (or father) who quits drinking’s future children are less likely to be alcoholics.

We are all products of both our environment and our genetics. Epigenetics studies the former rather than the latter. Or more specifically, epigenetics studies how environmental factors can affect how genes work. But it isn't about changes to a person's DNA itself.

In your example, both the mother and the children experience prolonged alcohol exposure which can have long-term or permanent effects on neural pathways. However these are physical changes in response to the environment. They are not changes to the genetic code in either the mother or child. In fact, these changes are by definition not being passed on genetically from mother to child because that process only happens when the sperm fertilizes the egg.

Alcohol exposure in the womb is an environmental factor that conditions the child to alcohol and damages neural pathways. But it does not re-write either the mother or child's DNA to add an alcohol dependence gene of some sort which can then be passed on down to future generations.

The Central Dogma of Biology is just something I cited as an example of a scientific theory. It was proposed and given a rather grandiose name by Francis Crick in the 1950s after he and Watson discovered the molecular structure of DNA. It is a scientific theory because it provides an EXPLANATION of HOW genetic information flows within organisms. https://en.wikipedia.org/wiki/Central_d ... ar_biology

[Josh]

In your example, both the mother and the children experience prolonged alcohol exposure which can have long-term or permanent effects on neural pathways. However these are physical changes in response to the environment. They are not changes to the genetic code in either the mother or child. In fact, these changes are by definition not being passed on genetically from mother to child because that process only happens when the sperm fertilizes the egg.

You seem to be inventing a hypothesis on the spot to explain what is now standard, settled science. I think you shouldn't do this. Your conclusion above is not what the peer-reviewed research says.

Alcohol exposure in the womb is an environmental factor that conditions the child to alcohol and damages neural pathways. But it does not re-write either the mother or child's DNA to add an alcohol dependence gene of some sort which can then be passed on down to future generations.

How an organism develops depends o more than just their DNA. I have always found this kind of determinism interesting. Epigenetic expression is just as important as your DNA; after all, you share a lot of DNA with a potato, and the key difference is in expression.

The same observations for alcohol/alcoholism have also been observed with obesity. Obesity during pregnancy is more likely to mean an obese child from epigenetic factors.

The Central Dogma of Biology is just something I cited as an example of a scientific theory. It was proposed and given a rather grandiose name by Francis Crick in the 1950s after he and Watson discovered the molecular structure of DNA. It is a scientific theory because it provides an EXPLANATION of HOW genetic information flows within organisms. https://en.wikipedia.org/wiki/Central_d ... ar_biology

It's nice that you have a dogma from the 1950s, but it does not align with observed reality.

Ken, I will try to say this to you politely. When you engage both me (and others), I feel like you do this:

- Talk down to me
- Make remarks that I don't understand something or don't know what I'm talking about
- Offer long "explanations" that are simply a repeat of your own opinion, but presented as uncontested facts
- Offer links to simple explanations (like the Wikipedia link above), assuming I have not read the topic on Wikipedia - or anywhere else

I am not one of your students in your classroom and you are not my teacher. I feel you need to learn to engage us here as peers, not people you impart knowledge to from on high.

[Ken]

In your example, both the mother and the children experience prolonged alcohol exposure which can have long-term or permanent effects on neural pathways. However these are physical changes in response to the environment. They are not changes to the genetic code in either the mother or child. In fact, these changes are by definition not being passed on genetically from mother to child because that process only happens when the sperm fertilizes the egg.

You seem to be inventing a hypothesis on the spot to explain what is now standard, settled science. I think you shouldn't do this. Your conclusion above is not what the peer-reviewed research says.

Alcohol exposure in the womb is an environmental factor that conditions the child to alcohol and damages neural pathways. But it does not re-write either the mother or child's DNA to add an alcohol dependence gene of some sort which can then be passed on down to future generations.

How an organism develops depends o more than just their DNA. I have always found this kind of determinism interesting. Epigenetic expression is just as important as your DNA; after all, you share a lot of DNA with a potato, and the key difference is in expression.

The same observations for alcohol/alcoholism have also been observed with obesity. Obesity during pregnancy is more likely to mean an obese child from epigenetic factors.

The Central Dogma of Biology is just something I cited as an example of a scientific theory. It was proposed and given a rather grandiose name by Francis Crick in the 1950s after he and Watson discovered the molecular structure of DNA. It is a scientific theory because it provides an EXPLANATION of HOW genetic information flows within organisms. https://en.wikipedia.org/wiki/Central_d ... ar_biology

It's nice that you have a dogma from the 1950s, but it does not align with observed reality.

Ken, I will try to say this to you politely. When you engage both me (and others), I feel like you do this:

- Talk down to me
- Make remarks that I don't understand something or don't know what I'm talking about
- Offer long "explanations" that are simply a repeat of your own opinion, but presented as uncontested facts
- Offer links to simple explanations (like the Wikipedia link above), assuming I have not read the topic on Wikipedia - or anywhere else

I am not one of your students in your classroom and you are not my teacher. I feel you need to learn to engage us here as peers, not people you impart knowledge to from on high.

You used fetal alcoholism and epigenetics as examples to refute the notion that environmentally acquired traits cannot be inherited because they do not re-write a person's DNA. When in fact your examples prove the exact opposite. Look up any definition of epigenetics if you don't believe me.

Environmental stresses that a fetus undergoes in the womb are not genetic traits that the fetus is inheriting from the mother's DNA. They are no different from the constant environmental stresses that all organisms experience inside or outside of the womb. And they are not genetic modifications that get passed down to future generations.

[Josh]

You used fetal alcoholism and epigenetics as examples to refute the notion that environmentally acquired traits cannot be inherited because they do not re-write a person's DNA. When in fact your examples prove the exact opposite. Look up any definition of epigenetics if you don't believe me.

Environmental stresses that a fetus undergoes in the womb are not genetic traits that the fetus is inheriting from the mother's DNA. They are no different from the constant environmental stresses that all organisms experience inside or outside of the womb. And they are not genetic modifications that get passed down to future generations.

What is significant is that maternal behaviour can end up permanently changing her offspring's behaviour for life, which will in turn affect that child's eventual offspring too.

I don't believe in DNA "determinism", that is, how children inherit traits from parents is much more than just downloading a copy of their sequenced DNA.

[Ken]

You used fetal alcoholism and epigenetics as examples to refute the notion that environmentally acquired traits cannot be inherited because they do not re-write a person's DNA. When in fact your examples prove the exact opposite. Look up any definition of epigenetics if you don't believe me.

Environmental stresses that a fetus undergoes in the womb are not genetic traits that the fetus is inheriting from the mother's DNA. They are no different from the constant environmental stresses that all organisms experience inside or outside of the womb. And they are not genetic modifications that get passed down to future generations.

What is significant is that maternal behaviour can end up permanently changing her offspring's behaviour for life, which will in turn affect that child's eventual offspring too.

I don't believe in DNA "determinism", that is, how children inherit traits from parents is much more than just downloading a copy of their sequenced DNA.

Well yes, we are all the result of BOTH environmental and genetic factors. No one has ever claimed anything to the contrary.

The only claim is that environmental traits that a person acquires during their lifetime do not get recoded back into their DNA in the form of new genes to be passed down to future generations. Prior to our modern understanding of molecular genetics and DNA this was something that people thought actually happened. That for example, if you trained really hard to improve your strength, that acquired trait of increased strength would be passed on down to your offspring. Now we know it isn't true.

[Josh]

The only claim is that environmental traits that a person acquires during their lifetime do not get recoded back into their DNA in the form of new genes to be passed down to future generations. Prior to our modern understanding of molecular genetics and DNA this was something that people thought actually happened. That for example, if you trained really hard to improve your strength, that acquired trait of increased strength would be passed on down to your offspring.

Once again, the whole point of what I said with epigenetics is that behaviour from parents does end up being a trait that their offspring have.

Now we know it isn't true.

You may want to reacquaint yourself with whatever this is that you think "we" know. It turns out (particularly with certain traits most of us would think are negative) that parental behaviour can strongly impact traits that offspring end up having. Maternal obesity causing offspring to be more likely to be obese is a very good example.

For example:

Obesity Heritability through Sperm?

Is it possible that some of these changes are heritable? Obesity runs in families, with the usual questions of nature vs. nurture, but some researchers are starting to believe that parents’ obesity itself (independent of their DNA) could affect a child’s epigenome. A study by Danish researchers in December in Cell Metabolism implicates an epigenetic mechanism in sperm that could potentially tend a child toward obesity. A comparison of the sperm of 13 normal weight subjects and 10 obese subjects showed a “distinct epigenome that characterizes human obesity” with distinguishing small noncoding RNA expression and DNA methylation patterns, particularly in genes controlling brain development and function.

The study also examined the sperm of morbidly obese men who underwent gastric bypass before the surgery and, a year later, after weight loss. They found “a dramatic remodeling of sperm DNA methylation, notably at genetic locations implicated in the central control of appetite” back toward the lean type.

“Everybody in the field is very excited about this study,” says Simmons. “But the question remains whether those changes can be transmitted to the offspring to result in a phenotype.” Simmons is cautious in interpreting many results, pointing to the perennial issue that association is not causation. Teasing out causes will take a lot more work. “We know that there are changes. We know that they can be reversed. But we don’t know how they influence the phenotype,” she says.

[Ken]

The only claim is that environmental traits that a person acquires during their lifetime do not get recoded back into their DNA in the form of new genes to be passed down to future generations. Prior to our modern understanding of molecular genetics and DNA this was something that people thought actually happened. That for example, if you trained really hard to improve your strength, that acquired trait of increased strength would be passed on down to your offspring.

Once again, the whole point of what I said with epigenetics is that behaviour from parents does end up being a trait that their offspring have.

Now we know it isn't true.

You may want to reacquaint yourself with whatever this is that you think "we" know. It turns out (particularly with certain traits most of us would think are negative) that parental behaviour can strongly impact traits that offspring end up having. Maternal obesity causing offspring to be more likely to be obese is a very good example.

For example:

Obesity Heritability through Sperm?

Is it possible that some of these changes are heritable? Obesity runs in families, with the usual questions of nature vs. nurture, but some researchers are starting to believe that parents’ obesity itself (independent of their DNA) could affect a child’s epigenome. A study by Danish researchers in December in Cell Metabolism implicates an epigenetic mechanism in sperm that could potentially tend a child toward obesity. A comparison of the sperm of 13 normal weight subjects and 10 obese subjects showed a “distinct epigenome that characterizes human obesity” with distinguishing small noncoding RNA expression and DNA methylation patterns, particularly in genes controlling brain development and function.

The study also examined the sperm of morbidly obese men who underwent gastric bypass before the surgery and, a year later, after weight loss. They found “a dramatic remodeling of sperm DNA methylation, notably at genetic locations implicated in the central control of appetite” back toward the lean type.

“Everybody in the field is very excited about this study,” says Simmons. “But the question remains whether those changes can be transmitted to the offspring to result in a phenotype.” Simmons is cautious in interpreting many results, pointing to the perennial issue that association is not causation. Teasing out causes will take a lot more work. “We know that there are changes. We know that they can be reversed. But we don’t know how they influence the phenotype,” she says.

Look, I just made a side reference to a basic theory of biology that is found in every basic textbook. I referenced it as an aside as part of a larger point about scientific theories in general. Can you find very fringe examples that might prove to be exceptions? Sure. Soloist mentioned some. However the epigenetic research you are citing are not exceptions. Right there in the text you cited they state they are talking about changes that are "independent of their DNA" Will future research discover a parent's acquired obesity can actually recode their DNA? Maybe. Who knows. That will be an interesting new development and theories will have to be revised. That is science and what makes it interesting.

In any event, you aren't arguing with me. This isn't some principle of biology that I invented and am defending. It is a complex theory that I summarized in a very simplistic manner. What you are now arguing against is a strawman caricature of a very complex principle of biology. Go for it if you want. But none of this relates at all to the subject at hand.