Evolution?

[juvenissun]

Hehe, perhaps. I haven't read up on it too much lately, so what I know of it is a bit hazy (about 2 years ago hazy). But as far as I remember, epigenetics is a change in gene expression, but not of the underlying DNA. It can be passed on to a next generation, but isn't permanent in the sense that the next generation can loose it again and thus revert to the previous condition if the enabling mechanisms behind the gene expression are lifted. Perhaps if I ammend what I said to "passed on to the next generations"?


Do I look very dumb if I cannot place your comment here? I generally evade threads with dad in them. Threads with AV in them I can bear up to a certain amount, but with AV the insanity goes into such extreme overdrive that I cannot feel anything other than pity for the guy. I keep wondering what they did to him?

This is another example. While I know little about what you guys talking about, but I know it is NOT directly related to the main argument of micro-evolution.

Stuff genetic content into the definition of micro-evolution is a bad thinking.

 

[Blayz]

Reference please! Sounds like something I'd want to read.

Sorry mate, this comes under "personal communication". I was doing some consultancy work for a research group and they explained that the disease in question was epigenetically inherited, and that the methylation they were studying was a consequence of the silencing, not the cause.

Hehe, perhaps. I haven't read up on it too much lately, so what I know of it is a bit hazy (about 2 years ago hazy). But as far as I remember, epigenetics is a change in gene expression, but not of the underlying DNA. It can be passed on to a next generation, but isn't permanent in the sense that the next generation can loose it again and thus revert to the previous condition if the enabling mechanisms behind the gene expression are lifted. Perhaps if I ammend what I said to "passed on to the next generations"?

Epigenetics is not limited to a single generation. In the above example the disease was present in many generations.

I don't think "change in allele frequency" cuts it as a definition of evolution any more. It should be amended to "change in allele frequency and expression"

 

[TheGnome]

Thanks for the introduction of term: quantitative genetics.

My argument in this thread, can now be read as: quantitative genetics is not appropriate to be used on the study of bacteria, because bacteria seldom change their morphology.

Bold emphasis is demonstratively false. I've shown you three pictures of bacteria with wildly different morphology. Hell, S. coelicolor has 63 sigma factors and S. aureus only has 4! That's just in sigma factors.

Why do you think bacteria are not that much different from each other?

 

[TheGnome]

Epigenetics is not limited to a single generation. In the above example the disease was present in many generations.

I don't think "change in allele frequency" cuts it as a definition of evolution any more. It should be amended to "change in allele frequency and expression"

This is correct. There's an interesting paper out that I've read concerning this new area of research: Epigenetics for ecologists by Oliver Bossdorf, Christina L. Richards and Massimo Pigliucci

I didn't want to bring it up because it's cutting edge kind of research and juvenissun is having problems with even the most basic established issues. He might pull a supersport now.

 

[Tomk80]

This is another example. While I know little about what you guys talking about, but I know it is NOT directly related to the main argument of micro-evolution.

euh, yes it is, even in your own fantasy world definition. Epigenetics can cause morphological changes.

Stuff genetic content into the definition of micro-evolution is a bad thinking.

No, it is accurate thinking.

 

[Tomk80]

Epigenetics is not limited to a single generation. In the above example the disease was present in many generations.

Okay, interesting. It's one of those areas of research I really need to read up on.

I don't think "change in allele frequency" cuts it as a definition of evolution any more. It should be amended to "change in allele frequency and expression"

Well, "change in allele frequency" was out already with evodevo as far as I'm concerned. The allele frequencies never change there, the regulation of genes does. "Change in genetics" or indeed "change in allele frequency or expression" is probably better indeed.

 

[Tomk80]

This is correct. There's an interesting paper out that I've read concerning this new area of research: Epigenetics for ecologists by Oliver Bossdorf, Christina L. Richards and Massimo Pigliucci

I didn't want to bring it up because it's cutting edge kind of research and juvenissun is having problems with even the most basic established issues. He might pull a supersport now.

Can't we just turn this thread into a thread on epigenetics? Much more interesting.

 

[Naraoia]

Sorry mate, this comes under "personal communication". I was doing some consultancy work for a research group and they explained that the disease in question was epigenetically inherited, and that the methylation they were studying was a consequence of the silencing, not the cause.

Is this likely to be published any time soon?

I don't think "change in allele frequency" cuts it as a definition of evolution any more. It should be amended to "change in allele frequency and expression"

That's a good point.

 

[juvenissun]

Can't we just turn this thread into a thread on epigenetics? Much more interesting.

How is that related to bacteria?

 

[juvenissun]

Bold emphasis is demonstratively false. I've shown you three pictures of bacteria with wildly different morphology. Hell, S. coelicolor has 63 sigma factors and S. aureus only has 4! That's just in sigma factors.

Why do you think bacteria are not that much different from each other?

Did you demonstrate a bacterium change its sigma factor through time, so it also changed its morphology?

 

[juvenissun]

euh, yes it is, even in your own fantasy world definition. Epigenetics can cause morphological changes.


No, it is accurate thinking.

I said A with a reason. You replied: not A.

You are getting very bad in debate.

 

[Tomk80]

I said A with a reason. You replied: not A.

You are getting very bad in debate.

Just doing the same as you are doing, Juvenissun.

The problem is that whether genetic change does or does not lead to morphological change, the process is the same. The effects are different, changing for example metabolism instead of morphology, but this has to do with the area in the genome where the process acts, not with the process being inherently different. You want to give the same process two different names. Biologists give the same process the same name.

 

[Blayz]

Is this likely to be published any time soon?

I am moving to another country to take up a new job, so might not get back to them before I leave. However, I will do my best to get what info I can.

 

[Tomk80]

How is that related to bacteria?

Epigenetic changes happen in bacteria to. It's in bacteria that they have been discovered, after which we discovered it also works in other organisms.

But more importantly, even if it wasn't it's more interesting than your constant naysaying.

 

[juvenissun]

Just doing the same as you are doing, Juvenissun.

The problem is that whether genetic change does or does not lead to morphological change, the process is the same. The effects are different, changing for example metabolism instead of morphology, but this has to do with the area in the genome where the process acts, not with the process being inherently different. You want to give the same process two different names. Biologists give the same process the same name.

I can understand what you said. But you do not get what I said.

Genetically, every life evolves. But that is NOT what the creation/evolution debate is about. You missed the theme of this thread. That is why I kept bring up dinosaur etc. in the argument. I want to compare bacteria with other life forms and not to look at the bacteria alone.

 

[paug]

You're not going to get anywhere with such rudimentary knowledge in the mechanisms of evolution. You are going to misunderstand or be misunderstood at every turn, stumble on terminology and shift the goalposts whenever you're showed a viable answer. But this thread has been quite fun to follow.

 

[Naraoia]

I am moving to another country to take up a new job, so might not get back to them before I leave. However, I will do my best to get what info I can.

Thanks

 

[Naraoia]

I can understand what you said. But you do not get what I said.

Genetically, every life evolves. But that is NOT what the creation/evolution debate is about. You missed the theme of this thread.

Given that you went into this pointless argument about the definition of evolution instead of just admitting you are trying to discuss some subset of evolutionary events, the theme wasn't that hard to miss. Maybe if you hadn't insisted that our definition is Wrong and bacteria don't evolve we would've got your "theme" easier.

 

[TheGnome]

Did you demonstrate a bacterium change its sigma factor through time, so it also changed its morphology?

I'm confused by this. Are you only concerned about an organism's appearance? Differences in morphology is really easy to find among bacteria as I've demonstrated with photos. Sigma factors don't affect the morphology of those organisms, they're to demonstrate how different they can be on all levels. Bacteria are a complex group.

That said, I guess the argument has shifted to demonstrating their evolution. I guess you disagree with techniques of putting the pieces of the past together, such as examining the genetics of these organisms using phylogenetics. I'm no microbiologist, so I don't know what kind of studies they've done to change the morphology of a particular bacterium. I know of studies where new physiological functions have evolved in bacteria. Morphology generally isn't complex, but physiology is complex. I don't know what kind of argument against evolution you could make out of that.

 

[juvenissun]

I like to quit this thread. Basically, I, a geologist, am talking to a bunch of people who study genetics. Geology (paleontology) and genetics are two different studies. Unfortunately, they shared the use of the same word: evolution. The definition is different and the content is different. This miscommunication started right from the beginning of this thread. And, it took me a while to find it out. Just like what TheGnome is puzzled, yes, I am (mostly) interested in the morphology and it is what the OP meant right at the beginning.

Well, anyway, I learned. Thanks to everyone.