Bacterial evolution refers to the process by which bacteria change over time through genetic variations. These changes can occur due to mutations, gene transfer, or environmental pressures. As bacteria reproduce rapidly, even small genetic changes can spread quickly through populations, allowing them to adapt to new conditions. One significant aspect of bacterial evolution is antibiotic resistance. When exposed to antibiotics, some bacteria may survive due to genetic mutations that confer resistance. Over time, these resistant bacteria can become more common, making infections harder to treat. This highlights the importance of understanding bacterial evolution in public health and medicine.