[matheusmoreira]

It makes sense. Same thing happens with antibiotic resistance, for example. It costs them energy and nutrients to develop and maintain resistance capabilities. Previously resistant bacteria may become sensitive again if exposure to the antibiotic ceases. The logic is they will be wasting energy duplicating and expressing useless DNA and proteins whose only purpose is dealing with antibiotics that are no longer present, so getting rid of them increases fitness because it frees up resources for other purposes.

Bacteria evolve frighteningly quickly.

[ByersReason]

Totally happens even with insects. The biotech industry started using BT genes (a fungus which takes care of corn ear worm) in GMO corn. Previously, BT was an organically approved pesticide, carefully applied by growers according to guidelines which made sure the target pest did not develop resistance. But with the genes making the nasties continually = BT all the time = excellent evolutionary driver = cases of resistant corn ear worm appearing. Biotech reaction: "we will just think of something new and keep doing it!" ref: https://entomologytoday.org/2018/10/23/problems-driving-resi...

[saalweachter]

> Previously, BT was an organically approved pesticide, carefully applied by growers according to guidelines which made sure the target pest did not develop resistance.

Excuse me, I'll just be over here laughing so hard I can't breathe.