Evolution?

[juvenissun]

Originally Posted by juvenissun

Yes, you did give a few examples. However, it is not easy for me to evaluate your examples. The only thing I can tell is that your examples do not represent the normal situation.

What "normal situation". If it happens in nature, it is normal.

No. the normal in a statistic sense.

As a scientist, you should bear the scientific meaning of this word in your mind all the time.

 

[juvenissun]

To evaluate the changes that happened to animals, we need the exact same criterium. Of course, we can also use morphology to determine what happened with bacteria, another thing that you continuously keep ignoring. Not all bacteria look alike, for from it.

This is great. Could you show me an example that illustrates the morphological evolution of bacteria?

 

[Wiccan_Child]

No. the normal in a statistic sense.

As a scientist, you should bear the scientific meaning of this word in your mind all the time.

I submit this post as proof that juvenissun is a troll, and a successful one at that. While repeatedly flouting scientific terminology for his own bizarre and inconsistent concoctions, he then has the audacity to berate someone for apparently doing the same thing! The icing on the cake is that the person didn't do what juvenissun does!

So yeah, I'm unsubscribing. Please don't feed the troll, folks.

 

[TheGnome]

This is great. Could you show me an example that illustrates the morphological evolution of bacteria?

This is Streptomyces coelicolor. It has 63 different sigma factors.

This is Staphylococcus aureus and it only has 4 sigma factors

This is Pseudomonas aeruginosa and contains 24 different sigma factor.

Sigma factors are required for transcription to take place. One is primarily used for all transcription, however, the others are used in special circumstances, such as in case of emergency.

 

[Tomk80]

No. the normal in a statistic sense.

Given the multitude of ways that speciation can occur and the enormous diversity in nature regarding this, I very much doubt that bacteria can be considered abnormal in a statistical sense.

edited to add: I doubt that what Juvenissun means when he says speciation is even the norm in the animal world.

As a scientist, you should bear the scientific meaning of this word in your mind all the time.

Cut the crap, you don't reason like this in any part of this thread, neither did you do so regarding "normal" with animals.

 

[Naraoia]

Yes, you did give a few examples. However, it is not easy for me to evaluate your examples.

Then please refrain from dismissing them.

The only thing I can tell is that your examples do not represent the normal situation.

What makes you think that, and what would be the "normal" situation?

Then, the classification scheme issue came. We found that species, genus, class etc. are NOT the same thing used on bacteria and on animals.

So what? It's a language issue and not a biological one. We happen to call both a rose and the Old Red Sandstone "red" but that doesn't in any way indicate that the two must be the same colour. Does this carry any profound meaning about colours, rocks or roses? No. The only thing it tells us anything about is how our brains process the situation.

Use the word "lineage" or "clade" if you like. That means the same thing in any form of life: descendants of a given ancestor. If you really need ranks then use degrees of genetic difference or something that's more than just a language construct.

So my definition of evolution (speciation) may not apply to bacteria either (progress and learning to me). Obviously, we need to use an entirely "different" criteria (genetic) to evaluate the changes happened to bacteria. While I agree that evolution "can be" defined as change with time, it is not the one underlain the OP.

Again, then don't call it evolution. If we don't know what you want then don't expect us to answer your questions.

In the evolution/creation debate, the default definition of evolution is the species evolution happened to plants/animals.

Which is a sure sign that most creationists are in dire need of basic biology education.

It seems that we can agree now that this definition does not apply to bacteria.

Species is hardly more than a label that we stick to groups of organisms so we can identify them.

Now, a vague or an improperly defined term does not eliminate the problem. Bacteria, one of the earliest form of life appeared on the earth, are still dramatically different from megascopic form of lives in their mechanism of evolution.

Dramatically? Well, they reproduce and exchange genes in a different way (but then not all eukaryotes are sexual, and we also get random genes from other things - a huge portion of the human genome is retroviruses). I guess you have to use different population genetic models for them. But they mutate just like we do, they are subject to selection just like we are, and selection has the same effect on their mutations as it has on ours. Where is this dramatic difference?

With this understanding or modification, the question in the OP STILL STANDS. All the debates happened so far only served to clarify the question of the OP.

Clarify? I think I have less idea of what you're asking than I had at the beginning.

 

[Split Rock]

May be what you said is true. Only lives created on Day 5 (and Day 6) are counted as lives. That is why Adam (and animals) is allowed to eat plants (not lives).

Folks, this is what happens when you take a Bronze-Age creation Story and try to make it God's Inerrant Word. Adam was allowed to eat plants, because plants are not alive. Yes, that is correct, folks. We must ignore the obvious contradiction that plants can die, plants need food, plants grow, plants respond to the environment, plants undertake homeostasis, and plants reproduce. Juvenissun says the Bible states they are not alive. So let it be written... so let it be done!

 

[juvenissun]

Dramatically? Well, they reproduce and exchange genes in a different way (but then not all eukaryotes are sexual, and we also get random genes from other things - a huge portion of the human genome is retroviruses). I guess you have to use different population genetic models for them. But they mutate just like we do, they are subject to selection just like we are, and selection has the same effect on their mutations as it has on ours. Where is this dramatic difference?

Size difference?

 

[juvenissun]

Folks, this is what happens when you take a Bronze-Age creation Story and try to make it God's Inerrant Word. Adam was allowed to eat plants, because plants are not alive. Yes, that is correct, folks. We must ignore the obvious contradiction that plants can die, plants need food, plants grow, plants respond to the environment, plants undertake homeostasis, and plants reproduce. Juvenissun says the Bible states they are not alive. So let it be written... so let it be done!

My reply was not to you. I won't say the same thing to you (or to any non-believers in this forum), as you would never understand anything of it.

See, Assyrian, this is a consequence when you start to talk about heavenly issue and read by earthly people.

 

[juvenissun]

The only thing I can tell is that your examples do not represent the normal situation.

What makes you think that, and what would be the "normal" situation?

It was a while ago. When I asked for examples of muti-cellular bacteria, he gave me two examples (can't remember clearly). I am not sure if the examples shown real multi-cellular bacteria (one I said is a colony, rather than a true multi-cellular bacterium. But the cell in the middle of the chain puzzled me). But I am sure if they do, they are exceptions rather than normal. And are possibly rare exceptions, i.e. statistically insignificant examples. The normal situation is that 99% of bacteria are single-celled lives.

Sorry if my memory burred. This issue is not my thing and I could not put information together efficiently enough.

 

[juvenissun]

This is Streptomyces coelicolor. It has 63 different sigma factors.

This is Staphylococcus aureus and it only has 4 sigma factors

This is Pseudomonas aeruginosa and contains 24 different sigma factor.

Sigma factors are required for transcription to take place. One is primarily used for all transcription, however, the others are used in special circumstances, such as in case of emergency.

Are you suggesting that we can find bacteria made of different number of sigma factors and that represents or illustrates the change of bacterial morphology through evolution?

I don't have time to search for information. But I guess the sigma factor is too small (in size) to affect the morphology of a bacterium.

Thanks for the nice images. While looking at them, It occurred to me that may be I should ask this question: what are the factors that control the shape of a bacterium? Another hunch is that the variation on the shape and size of bacteria is quite limited. Right?

One side question is how could a SEM operated on 4 KV but is able to focus well under 10,000X magnification?

 

[Split Rock]

Thanks for the nice images. While looking at them, It occurred to me that may be I should ask this question: what are the factors that control the shape of a bacterium? Another hunch is that the variation on the shape and size of bacteria is quite limited. Right?

How did you come to that strange conclusion by looking at images of very different shaped bacteria?

 

[Split Rock]

My reply was not to you. I won't say the same thing to you (or to any non-believers in this forum), as you would never understand anything of it.

See, Assyrian, this is a consequence when you start to talk about heavenly issue and read by earthly people.

So would I need to be guided by the Holy Spirit in order to understand that living organisms like plants are not really alive? Or do you have some other explanation?

 

[Tomk80]

It was a while ago. When I asked for examples of muti-cellular bacteria, he gave me two examples (can't remember clearly). I am not sure if the examples shown real multi-cellular bacteria (one I said is a colony, rather than a true multi-cellular bacterium. But the cell in the middle of the chain puzzled me). But I am sure if they do, they are exceptions rather than normal. And are possibly rare exceptions, i.e. statistically insignificant examples. The normal situation is that 99% of bacteria are single-celled lives.

As is probably 99% of the non-bacteria.

Face it, what you're looking at (animals, more specifically mammals) is not the norm.

Sorry if my memory burred. This issue is not my thing and I could not put information together efficiently enough.

This issue is indeed clearly not your thing.

 

[Tomk80]

So would I need to be guided by the Holy Spirit in order to understand that living organisms like plants are not really alive? Or do you have some other explanation?

Always try to resort to religion when others see your verbiage for what it really is: nonsense.

 

[Bombila]

Juvenissun, you seem fixated on the size of bacteria, that they are small. Do you think size dictates something important about evolution? Is it your contention that a polar bear is somehow more evolved than a human or a mouse?

 

[TheGnome]

Are you suggesting that we can find bacteria made of different number of sigma factors and that represents or illustrates the change of bacterial morphology through evolution?

I don't have time to search for information. But I guess the sigma factor is too small (in size) to affect the morphology of a bacterium.

Thanks for the nice images. While looking at them, It occurred to me that may be I should ask this question: what are the factors that control the shape of a bacterium? Another hunch is that the variation on the shape and size of bacteria is quite limited. Right?

One side question is how could a SEM operated on 4 KV but is able to focus well under 10,000X magnification?

The images along with knowing the sigma factors were supposed to show how different they can be from each other.

You're just never going to get it, are you?

 

[Vene]

The images along with knowing the sigma factors were supposed to show how different they can be from each other.

You're just never going to get it, are you?

I don't think he wants to get it.

 

[Naraoia]

Size difference?

Size difference only means that you meet different challenges and different selective pressures. A small thing may have to prevent being blown out of its favourite spot by the wind; a large thing doesn't have to worry about that, but it has to have effective ways of transporting oxygen, nutrients etc. across its body.

I fail to see, though, how that's a fundamental difference between bacteria and eukaryotes (or animals, or whatever).

First, animals themselves cover a HUGE size range. Think blue whale versus flea - there are smaller animals than fleas but they are well-known and illustrate the point well enough. Does that mean there is a dramatic difference between flea and whale evolution?

Second, size is just one factor that influences the selective pressures you face. You could substitute any trait in which organisms differ: food sources, locomotion, living in salt water/fresh water/on land, heat tolerance or any number of other things. Does this mean that animals (eat organic stuff) and plants ("eat" carbon dioxide, other inorganic nutrients and sunlight) differ "dramatically" in their mechanisms of evolution?

 

[Naraoia]

It was a while ago. When I asked for examples of muti-cellular bacteria, he gave me two examples (can't remember clearly). I am not sure if the examples shown real multi-cellular bacteria (one I said is a colony, rather than a true multi-cellular bacterium. But the cell in the middle of the chain puzzled me). But I am sure if they do, they are exceptions rather than normal. And are possibly rare exceptions, i.e. statistically insignificant examples. The normal situation is that 99% of bacteria are single-celled lives.

Sorry if my memory burred. This issue is not my thing and I could not put information together efficiently enough.

Aren't the majority of eukaryotes unicellular too? Off the top of my head I can think of four eukaryotic groups that have many multicellular members:

- animals (all of them, by definition)
- plants (plus some red and green algae)
- fungi (but only some of them, not sure if it's the majority)
- brown algae

And there are a large number of other groups besides them, diverse and numerous, that are perfectly happy living the one-celled life.

(And yes, the cell in the middle - a heterocyst, a nitrogen-fixing cell - is a different cell type, so you could say that the cyanobacteria that have these cells are truly multicellular)