What evolutionary mechanisms might account for the origin and persistence of cell-to-cell signaling systems in prokaryotes?

Quorum sensing.

Explanation:

Quorum sensing may be defined as the phenomena by which the bacteria can detect the specific stimuli and respond towards the cell population density. This process helps in coordinating gene expression.

Quorum sensing is used in prokaryotes for the cell to cell signalling and cell communication as well. The main evolution of quorum sensing in bacteria was to relay the information and helps in cell signalling by releasing the specific toxins. From the evolutionary point, the organism that are capable of quorum sensing would survive more in their environment, adapt well in their environment.

Thus, the answer is quorum sensing.

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