Which of the four factors that affect evolution apply to the finches that the Grants studied? Use evidence from your research to support your answer.

The four factors that affect evolution are mutations, natural selection, genetic drift and the gene flow, In the case, if the ground finches that Grants studied, we can observe the working of the natural selection. Due to change in the conditions in the environment, the large beak was an advantageous trait that was favored by the natural selection. The result of this process was an increase in numbers of large beaked finches and decrease in small-beaked finches compared to the initial numbers in the population.