Bill makes a good point re antibiotic resistance. However, my understanding is that this is about "training" your immune system to seek and destroy. Whether there has been an irreversible change in the molecular makeup of your antibodies goes to the heart of what we term evolution.

If your children retain that genetic memory, is that because the mother has passed on sufficient antibody intact or the DNA ability to produce it? Moot point. (Not just bacterial either, viral too.)

HIV itself, regardless of host is altering, as a good example of evolution. In order to evade antiretrovirals, the strain is becoming better at hiding but less virulent in doing so and it is (fingers crossed) expected to become a condition of first to catch a cold, guaranteed to catch what is going round etc in around a hundred years from now. Even where no treatment is around, the time taken to developing AIDS had increased from seven to ten years over the last twenty years. (Source BMJ, last week.)

Evolution is, to my mind, not just what we can observe.