[AndrewC]

Then where did the sulfa drug resistance genes go when you claimed they “disappeared”?

He claimed no such thing. This is what he stated.

This was well demonstrated by the the dissappearance of resistance to sulfa drugs over the last 40 years.

And turning off the ability makes the ability "disappear" which does not necessarily mean "cease to exist."

[allmendream]

I turn my car off after I finish driving. Amazingly my car cannot be said to have “disappeared”.

Presently my genes for digestion of lactose are off. The genes cannot be said to have “disappeared”, neither has my ability to digest lactose “disappeared”. If I ate some cereal with milk my lactase genes would turn “on”.

Now if the genes to survive sulfa drugs are present in every bacteria, but merely “off”, then what would be the difference between the 99.9% of bacteria that would die when exposed to sulfa drugs and the 0.1% that would survive?