|MadSci Network: Microbiology|
Loss of Antibiotic Resistance?
Your hypothesis sounds good, but it is not as easy as you might think.
You’re right that animals that live in caves might lose their color, however, this may take a long time, as in many many years or many generations. They may also develop new traits such as, better hearing mechanisms or sonar detection systems.
The case for the loss of antibiotic resistance is also not clean cut. Most antibiotics belong to families of drugs that are very similar. Therefore, related antibiotics may continue the presence of other resistance genes for other antibiotics. Also, by definition, antibiotics originate from microorganisms – they actually are microbial defense mechanisms. Antibiotic resistance has been part of the evolution of bacteria as a means of survival among antibiotic-producing competitors. Therefore, these resistance mechanisms will always be present to some extent in nature.
Even after withdrawal of an antibiotic with the loss of resistance, whenever the antibiotic was re-introduced potential random mutations may occur, which will lead to the re-appearance of resistance.
Reference: Bailey & Scott’s Diagnostic Microbiology 10th edition, Chapter 17.
The opinions expressed above are my own and may not reflect those of my employer.
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