What is the difference between natural selection and evolution?

Evolution is the gradual change in the alleles of a species over time to make it more suited to its environment. Natural selection is when certain members of a population have an advantageous allele making them more adapted to their environment, usually as a result of random mutation. These members are more likely to survive, reproduce and pass on their advantageous alleles to the offspring. Although natural selection and evolution are different processes, natural selection can result in evolution.For example, the peppered moth. Some moths had darker than normal colouring, due to pollution, making them less likely to be spotted by prey. This meant the darker coloured moths survived and reproduced, passing on the advantageous allele for darker colouring onto their offspring. This process is natural selection. The offspring with darker colouring were also more likely to survive and reproduce and pass the allele onto their offspring. Eventually all of the moths in the population had darker colouring. This overall change is known as evolution.