Of course, a mutation that produces a beneficial change is not the same as microbe-to-man evolution. In order for that to occur new information has to appear in the DNA to code for new features not previously seen in the species, and there are no examples of this in existence. However, mutation that damages DNA information, which is therefore the opposite of evolution, can sometimes be beneficial. Fish living in total darkness in waters inside a cave would benefit from losing their eyes, as eyes are no help where there is no light; but their eyes can be damaged by swimming into things, which could then lead to disease and death.In the case of Lenskiís experiment, E. coli benefitted by saving energy through losing some abilities that were previously there.