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in the late 1980's scientists began to notice that some strains of staphyloccoccus aureus bacteria were becoming resistant to topical antibiotics used by dermatologists to treat acne. By the year 2000 over 100 strains of staphyloccoccus were resistant to almost all antibiotics and scientists had to develop a new plan to kill the. Explain what happened geneticlly in the bacteria population over time as skin infections caused by staphyloccoccus aureus, were exposed to topical antibiotics.