[Mika]

Thanks misterJ for jumping in the bandwagon. Maybe we'll all learn something from this discussion after all. I like it when people from different fields of Science can talk about the same thing but the perspectives are usually very different!

period of generation ranges from about 20 minutes to several hours, in general. not that I see what that has to do with anything. yes this means they can evolve very very fast, but as I've said without a change in environment this means nothing.

Here, what does it mean "no change in environment"? Terms like these are awfully easy to throw around but show me a place where this actually holds! Mind you, this is now roughly atomic level stuff we are talking about! Physicists know it best that Mathematics is an abstraction and especially logic (as defined in Mathematics). What I think is that you are thinking in terms of mathematical abstraction when you have written some of the above. I don't bother to go through the whole thing today as it needs to be split into parts to check the validity of each, but I'll try to do it tomorrow.

The molecular level DNA copying already introduces random errors. Add some further noise to it from environmental conditions like radiation for example. So the conclusion of the research is: being resistant to antibiotics can happen without any antibiotic influence at all. Given the numbers of population, mutation rates, cross-over rates and time period between generations, I don't find it that difficult to believe. As an analogy, some people are able to do splits, while for some this is physically impossible without tearing some ligaments. It might be little details like this (in their scale) that determine if bacteria is able to withstand an antibiotic or not.

Yes I'm not Mars. Maybe I should restart putting my name also on the bottom of the messages to clear up confusions that people thought cannot happen.

[mister J]

that experiment does not address the origin of the resistant bacteria, it simply proves that resistant strains exist and are in the wild.

actually, what it does address is the fact that exposure to a treatment has nothing to do with whether resistance develops or not. It just happens that way at random.

It's kinda like how Lamarck and Darwin had differing opinions on how giraffes got longer necks. Darwin's idea, which is currently the one accepted today, is that Giraffes did not develop longer necks specifically because they needed to get to that higher foliage, it just happened that giraffes with longer necks had a better chance of survival. Those giraffes had little long necked babies and they flourished, having spread their advantageous phenotype to the next generation.

Just the same with bacteria. Bacteria did not suddenly adapt to antibiotics specifically because they were exposed to them, it just happened that bacteria existed that were resistant, having been born with a random mutation that makes them different, and had a better chance of survival. Those bacteria flourished through dividing or transferring their genetic info "horizontally*" and flourished, having spread their advantageous phenotype to generations in both their own and subsequent levels of the phylogenetic tree.

so to reiterate, in answering the question, "how do resistant strains exist?" Current evidence points to "it just happened at random." Given that  gazillions of any species of bacteria are created at any moment, it's not hard to believe. Selective pressure (such as antibiotic use) just accelerates the process by making the environment favorable to certain bacterial types, forcing them to adapt, by (again) random mutation.

*basically, one bacteria shares genetic information (which can include resistance) to another without creating offspring, which helps a bacteria evolve.

[General Battuta]

That was reaching pretty low, Bob.

Only in a community run and populated mostly by vaginas. Grow a pair, people.

Excuse me? The vagina is a mighty organ! The penis is fragile and delicate!

[Thaeris]

Excuse me? The vagina is a mighty organ! The penis is fragile and delicate!

Oh, you know what it's time for now, right?

CLITORIS!!!

 

[General Battuta]

Different organ, mate.

[Snail]

...

[Flipside]

Yeah, because it's perfectly alright to be rude and ignorant to other people, that's never caused any problems, ever...

Edit: Basically, 'everyone else does it' stopped being an excuse for me at the age of 12, and I don't consider it justification in here.

I will attempt to clean out the sensible discussion from the name-calling in that thread and seperate it out, that's an acceptable suggestion, but the idea that hurling personal insults at each other merely requires 'a thick skin' or that because it is 'just what the Internet is like', it is ok, is a self-delusion. It's what the Internet is like because of people doing it, not vice versa.