How does the development of antibiotic resistance in a population of bacteria support the theory of evolution through natural selection?
1 Answer
Evolution can be loosely defined as a change in a population - if the population changes over a period of time, and that change is an adaptation that improves fitness, it supports the theory.
Explanation:
Evolution by natural selection could be better defined as a change in the allele frequencies of a population in response to an external "selective" pressure.
This pressure (predators, limited resources, antibiotics) results in differential fitness in a population - those bacteria with the allele for resistance are better suited to survive than those without and as a result are more often successful at reproducing.
Over time, a population of bacteria will become resistant to an antibiotic in response to a constant selective pressure (application of antibiotics) - the frequency of resistance alleles in the gene pool will increase which we can define as "Evolution".
