A comparatively short generation time together with genetic flexibility. The latter means that within a microbial community, a number of variants exist due to point mutations in the genome, accumulated during replication. Moreover, microbes may take up external genetic material (different mechanisms: natural transformation, transduction, transfection), thereby acquiring additional characteristics. This genetic flexibility is the basic mechanism for adaptation and other mechanisms. In real time that does only mean, that a given species might be able to adapt to changing environments. Evolution by means of origination of novel species is nevertheless a slow process (in terms of human sense of time).

modification of genetic expression

A comparatively short generation time together with genetic flexibility. The latter means that within a microbial community, a number of variants exist due to point mutations in the genome, accumulated during replication. Moreover, microbes may take up external genetic material (different mechanisms: natural transformation, transduction, transfection), thereby acquiring additional characteristics. This genetic flexibility is the basic mechanism for adaptation and other mechanisms. In real time that does only mean, that a given species might be able to adapt to changing environments. Evolution by means of origination of novel species is nevertheless a slow process (in terms of human sense of time).

Different levels of evolution have their own main mechanisms.

If you look at difference between closely related genomes, (the same species) you will see that deletion and insertion of single genes is the main factor of their diversity (core genome stays stable). Thus, they must have high activity of mobile genetic elements.

Related species have re-arranged gene clusters (Ballouz S, et al. (2010) Conditions for the Evolution of Gene Clusters in Bacterial Genomes. PLoS Comput Biol 6(2): e1000672), as result of recombination and gene exchange with other species

Distant species have different core genomes and distant house-keeping genes as result of all possible mechanisms of evolution.

• Some of viruses shows antigenic shifts and antigenic drifts. Those mechanisms leads to arise new variations.
• Transformation, conjugation and transduction mechanisms helps to bacteria for their evolution.

Thank you.

https://globescience.net/origin-of-life-on-earth/

Well to answer in brief, lets remember the fact the different environments on this planet is very dynamic and so is the various ecosystems and habitats of different microorganisms i.e. ever changing. Therefore, in order to survive in such a system, every living systems including microorganisms must undergo adaptation, which is called as selection. It may be natural or anthropogenic. This is seen in the form of evolution or called as evolution..

Thanks for all these valuable inputs...

Dear colleagues, most of the proposed mechanisms are existed and may give microbes evolutionary precedence compared with antimicrobial. Is that make sense??! If so, which one evolves faster, the microbe or antimicrobial? If microbe does, what kind of future we shall have?

Thanks in advance.

This needs a specific answer and for this you must specify a microorganism and an antimicrobial too.