Creationists...What will it take?, page 8
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reply posted on 2-2-2005 @ 12:27 PM by mattison0922
As you are throughly admitting. The bacteria/viruses that are becomming immune to medicine's are gradually adapting to a large threat to living in some of their best breeding habitats (humans). This is the definition of evolution.

Please go back and re-read my post. Bateria are not 'becoming immune.' Evolution doesn't occur in individuals, it occurs in populations. There is nothing gradual about. Genes for immunity exist in populations... they don't arise as a result of a particular stressor. This genetic information was present already in the bacteria. Exposing bacteria to antibiotics merely selects for this gene. Bacteria haven't gained anything new from this. If you'd bothered to read AND think about what I've written, you'd realize that antibiotic resistance isn't equipping bacteria with anything new or improved. This is evidenced perfectly by the observation that antibiotic resistant bacteria are outcompeted by sensitive bacteria in the absence of this selective pressure. The genetic predisposition for antibiotic resistance ALREADY EXISTED within the population. Antibiotic resistance existed BEFORE the isolation and use of antibiotics. Evolution hasn't driven anything except the alteration of frequencies of a certain genetic character (that pre-existed) within a population.

It will either try to change to eliminate the ability to sustain damage or get rid of unneeded parts.

Statements like this merely demonstrate how poorly you understand this topic. Evolution doesn't attempt to do anything. There is no goal in this process. Evolution merely alters the frequencies of existing genetic information within populations.

The human is most likely the slowest evolving species on the planet. We actively evolve the world around us to suit our current state. Thus our bodies do not need to evolve as much or as frequently as others to survive.

Again, your utter lack of understanding comes shining through in this statement. Individuals don't evolve, populations do. What you actually mean to say is that humans have manipulated themselves and their environment such that certain selective pressures have been removed. The process of altering allelic frequencies doesn't cease though. Allelic frequencies ARE still being altered. What's happening, is that 'defective' or 'bad' genes are being allowed to persist within the gene pool. The process that is proposed to drive evolution doesn't cease because we can effectively manipulate certain aspects of our environment to compensate for inherited 'defects.'


reply posted on 4-2-2005 @ 08:15 AM by LuDaCrIs
Originally posted by mattison0922

Please go back and re-read my post. Bateria are not 'becoming immune.' Evolution doesn't occur in individuals, it occurs in populations. There is nothing gradual about. Genes for immunity exist in populations... they don't arise as a result of a particular stressor. This genetic information was present already in the bacteria. Exposing bacteria to antibiotics merely selects for this gene. Bacteria haven't gained anything new from this. If you'd bothered to read AND think about what I've written, you'd realize that antibiotic resistance isn't equipping bacteria with anything new or improved. This is evidenced perfectly by the observation that antibiotic resistant bacteria are outcompeted by sensitive bacteria in the absence of this selective pressure. The genetic predisposition for antibiotic resistance ALREADY EXISTED within the population. Antibiotic resistance existed BEFORE the isolation and use of antibiotics. Evolution hasn't driven anything except the alteration of frequencies of a certain genetic character (that pre-existed) within a population.



I dont know if i can agree with this. Are you saying that these bacteria are already immune to an anti-biotic before it was ever invented or produced??
Are you trying to say that there is no possible way to stop some bacteria because they are always going to be one step ahead?. What makes some baceria more special than others? Are there any bacteria that dont have some kind of immunity to any anti-biotic? If so then, do you think they will be able to gain immunity with progressive reproduction while being exposed to an anti-biotic. I am getting the impression that you think bacteria cant all of the sudden become resistent to anitbiotics because they already store that immunity somewhere and only when it needs to be used they use it. Am i right?.


reply posted on 4-2-2005 @ 09:07 AM by mattison0922
Originally posted by LuDaCrIs
I dont know if i can agree with this.

This is no great surprise.


Are you saying that these bacteria are already immune to an anti-biotic before it was ever invented or produced??

More or less. But first of all remember that antibiotics weren't 'invented,' they were just isolated. But I am saying that antibiotic resistant bacteria existed well before we knew about antibiotics. Consider the case noted by McQuire, "Eerie: human Arctic fossils yield resistant bacteria," Medical Tribune, 12/29/1988. Bacteria were recovered from the frozen bodies of a band of early Arctic explorers who died in 1845. The bacteria were recovered from their colons in 1988, carefully cultured and exposed to modern antibiotics. Many were found to be resistant to the most powerful modern antibiotics, demonstrating that antibiotic resistance was present ahead of time and has not "evolved" as a response to new selective pressures.

Are you trying to say that there is no possible way to stop some bacteria because they are always going to be one step ahead?.

That's not what I said at all. I stated that the genes for antibiotic resistance didn't arise as a result of antibiotic use. The genes ALREADY EXISTED in the population, and use of antibiotics resulted in an increase in the frequency of AR genes in the population.

What makes some baceria more special than others? Are there any bacteria that dont have some kind of immunity to any anti-biotic?

I don't understand the 'special' question. Please elaborate. I don't know about completely sensitive strains of bacteria. It seems like they're not on the radar so to speak.

If so then, do you think they will be able to gain immunity with progressive reproduction while being exposed to an anti-biotic.

No. There is no 'gain of immunity.' The bacteria that are immune live, those that are sensitive die, end of story. Immunity is either present in an individual or not. If it is, that individual is free to reproduce and the AR genes will proliferate in the population.


I am getting the impression that you think bacteria cant all of the sudden become resistent to anitbiotics

Bacteria can't suddenly become anything. They either are resistant or they aren't. Remember individuals don't evolve, populations do. AR stems only from genes already present in a population. It is noteworthy that bacteria can transfer genetic information horizontally, but this is still just transfer of PRE-EXISTING genetic information.

because they already store that immunity somewhere and only when it needs to be used they use it. Am i right?.

Well, sort of. They don't 'store it' until needed. It's a part of their regular genetic makeup. The AR is present in some already. Those that are AR survive and their genes are passed on, including AR genes.


reply posted on 4-2-2005 @ 10:32 AM by LuDaCrIs
Originally posted by mattison0922
More or less. But first of all remember that antibiotics weren't 'invented,' they were just isolated. But I am saying that antibiotic resistant bacteria existed well before we knew about antibiotics. Consider the case noted by McQuire, "Eerie: human Arctic fossils yield resistant bacteria," Medical Tribune, 12/29/1988. Bacteria were recovered from the frozen bodies of a band of early Arctic explorers who died in 1845. The bacteria were recovered from their colons in 1988, carefully cultured and exposed to modern antibiotics. Many were found to be resistant to the most powerful modern antibiotics, demonstrating that antibiotic resistance was present ahead of time and has not "evolved" as a response to new selective pressures.


Simply amazing. Didnt even know of such a case. I am fairly uneducated in this field, clearly not as much as you, and find this very interesting now that you've brought it up.


That's not what I said at all. I stated that the genes for antibiotic resistance didn't arise as a result of antibiotic use. The genes ALREADY EXISTED in the population, and use of antibiotics resulted in an increase in the frequency of AR genes in the population.


What i meant is, if the AR genes already exist, then how do we stop them if they are already immune to the anti-biotic, watever it is? If it's ALREADY in them then they will be one step ahead all the time since they can increase the frequency of AR genes in the population once we introduce the anti-biotic.

No. There is no 'gain of immunity.' The bacteria that are immune live, those that are sensitive die, end of story. Immunity is either present in an individual or not. If it is, that individual is free to reproduce and the AR genes will proliferate in the population.


Based on this, wat makes some bacteria more special than others?...WHy is it some have the immunity and others dont?


reply posted on 4-2-2005 @ 02:04 PM by mattison0922
Originally posted by LuDaCrIs
Simply amazing. Didnt even know of such a case. I am fairly uneducated in this field, clearly not as much as you, and find this very interesting now that you've brought it up.

Yes, I am chock full of interesting but pretty much completely impractical knowledge.


What i meant is, if the AR genes already exist, then how do we stop them if they are already immune to the anti-biotic, watever it is? If it's ALREADY in them then they will be one step ahead all the time since they can increase the frequency of AR genes in the population once we introduce the anti-biotic.

Well, this is the dilemma isn't it? The key is to decrease the frequency of AR genes as much as is possible... which would mean decreasing use of antibiotics overall. But in essence you are correct. The genes will most likely always be there, and use of ANY drug just increases resistance, especially in bacteria, which can have doubling times of about 20 minutes.

Based on this, wat makes some bacteria more special than others?...WHy is it some have the immunity and others dont?

A big part of it could have to do with the bacteria's ability to engage in horizontal gene transfer. You see bacteria can pass genes horizontally. The needn't reproduce to pass on genetic information. They can replicate AR genes INDEPENDENT of their other genes and pass them into the 'population.' Resistant vs. Sensitive bacteria could result from the bug's ability to take up these other genes. But within the same population, why some are immune and others are not is because of the slight variations that exist within individuals. Have you read "The Stand?" In that book, RANDOM people were immune to the Superflu (Cpt. Tripps). There was nothing special about them in particular, just luck of the draw. Just like there are certain people in the population that don't become addicted to nicotine (I'm one), just like there are people with sickle-cell anemia in a population, there are bacteria that are immune to the action of certain antibiotics. The strains that are resistant to multiple antibiotics result from concentration of all or most AR genes into a particular population. Generally the only occurs in an highly selective environment, like a hospital that uses tons of antibiotics and disinfectants.


reply posted on 13-2-2005 @ 12:51 PM by mattison0922
Originally posted by LuDaCrIs
THis is the one thing i cant get myself to belive as true.

The irony of this is that it's one of the vew verifiable and traceable instances or examples of 'evolution' that we've available to us.

Based on this we would have to conclude that there are no bacteria we could kill off,

Hmmmm.... I don't know how you got this from my posts. There are plenty of bacteria we can kill off, they are the antibiotic sensitive strains. However killing off the sensitive strains removes or reduces competition for the resistant strains, thus the resistant strains proliferate. I don't know that our goal should be to kill off any particular strain of bacteria.

because "the genes will most likely be there and use of ANY drug jsut increases resistence".

It is likely that alleles for resistance to pretty much whatever DO exist, and use of whatever selects for those resistant strains... it's natural selection, and it's pretty much inescapable.


If the gene, to become resistent, is always goin to be there why have we managed to kill off bacteria using anti-biotics?

We've not managed to 'kill off' bacteria using antibiotics. We've been able to control infection via the use of antibiotics. Use of antibiotics however leads to proliferation of resistance genes within the population. I don't see what's so difficult to comprehend about this.

Here is the deal: Antibiotics are substances that are produced by microorganisms. The organisms that produce antibiotics must be resistant to their action themselves. It also must be kept in mind that bacteria are capable of horizontal gene transfer, resistance can be passed WITHOUT dividing and mutating, etc. Resistance can be acquired EXTRACHROMOSOMALLY. Thus the very source of antibiotics is often also the source of resistance. Many antibiotics are derived from Streptomyces species... coincidentallly enough many resistance genes found in other varieties of bacteria show remarkable homology to those genes found in Streptomyces species, suggesting that Streptomyces is the likely source of antibiotic resistance in many cases.

Synthetic antibiotics are simply modifications of other natural antibiotics, and can often be defeated via mutation of existing genes. However even in the case of man-made chemicals... take DDT for example. To my knowledge the structure of DDT (shown here)
isn't based on any biomolecule and was pretty much unobserved in the natural world. However, DDT resistance in the common housefly has been tracked to a single point mutation. It is entirely likely that one cannot create a chemical to which all members of a population will be sensitive.


reply posted on 14-2-2005 @ 12:33 PM by Xerrog
Well I've been reading on Allelic frequencies and while you are right you are also wrong. Alleles are simply put variations in a given gene. These variations can and do happen in individuals. Most of the time when they happen in small groups that gene is to die out. Except in asexual lifeforms in which the gene variations tend to replicate and change farther.

Allelic frequencies are basically nothing more then a measurement of gene variations across a species. They represent a trend of evolution not a guarenteed path.


Since asexual lifeforms dont have their own variations overwritten by other dna/genes from another individual they will evolve more seperate and distinct "breeds" then other lifeforms. Thousands of generations down the line of one type of amoeba may and in many cases has multiple very distinct "breeds" with diffintive differences. Only when a entire "breed" or strain is eliminated will that specific allele strain stop.

That is individual evolution at its simplest.

Now in non-asexual lifeforms individual still have gene variation that is indepedent of the entire species, but many times it is limited in its abilitie to cause a true evolution simply because a dominant gene type in the other donating individual overrides it and erases it from that lineage.

If it does happen to make it through the first generation it has a much greater chance albeit a horribly small one of making it through the second. With each consecutive generation that variation its self can change more. If it does become a dominant trait it will survive and eventually become a notable allelic frequency. At that time it will be considered a evolved state.

Almost every individual everywhere of every species has its own individual evolutions. Most of them will never make it into the broader gene pool because they are not dominant traits. Some of them though can lie dormant for generations before reappering.

You describe evolution as the change of a species, but it does not happen magically overnight from some random energy source passing through the entire species.

Evolution starts with the individual, and after many many generations it might become inherint in the species.
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