First, how about addressing this question:
Is nylon-digesting bacteria considered to be a different type/species/kind of organism than non-nylon-digesting bacteria?
(Seems to me they’re clearly the same kind of organism (i.e. bacteria), just as a person vulnerable to sickle-cell anaemia is as much of a human being as a person not vulnerable to that disease. But macro-evolution is all about one kind of organism leading to distinctly different kinds. Like a bacterium becoming a bumble bee or a gnat. THAT’s the kind of “significant” I’m talking about.)
As far as your question – “Why would a bacteria as part of its stress response increase its mutation rate?” – assuming this is true, I don’t know why.
What I DO know, however, is that your statement – “…a bacteria under stress INTENTIONALLY increases its mutation rate in order TO INCREASE ITS CHANCES of successful evolution” presumes not only a type of CONSCIOUSNESS, but both an INTELLIGENCE and a WILL…in the lowly bacteria. I know that a true-blue evolutionist would never entertain such an idea of an organism directing/orchestrating its own evolution.
Here’s a bonus question…given it’s late and soon time for sleep, could you tell us some bed-time stories from the ToE about exactly how those things – consciousness, intelligence, will – evolved?
How about this link and an explanation?
Stress responses and genetic variation in bacteria.Foster PL.
Department of Biology, Indiana University, Jordan Hall, 1001 East Third Street, Bloomington, IN 47405, USA. pfoster@indiana.edu
Under stressful conditions mechanisms that increase genetic variation can bestow a selective advantage. Bacteria have several stress responses that provide ways in which mutation rates can be increased. These include the SOS response, the general stress response, the heat-shock response, and the stringent response, all of which impact the regulation of error-prone polymerases. Adaptive mutation appears to be process by which cells can respond to selective pressure specifically by producing mutations. In Escherichia coli strain FC40 adaptive mutation involves the following inducible components: (i) a recombination pathway that generates mutations; (ii) a DNA polymerase that synthesizes error-containing DNA; and (iii) stress responses that regulate cellular processes. In addition, a subpopulation of cells enters into a state of hypermutation, giving rise to about 10% of the single mutants and virtually all of the mutants with multiple mutations. These bacterial responses have implications for the development of cancer and other genetic disorders in higher organisms.