Question

consider a population of birds living on an island. suppose several individuals of the same species from a different population migrate to the island. due to the arrival of the new birds, the allele frequencies in the original population change. what mechanism of microevolution is at work in this example?

gene flow

genetic drift

natural selection

Explanation:

Gene flow refers to the transfer of genetic material (alleles) from one population to another. In this case, new birds (from a different population) arriving on the island introduce their alleles into the original bird population. This changes the allele frequencies of the original population. Natural selection involves survival and reproduction based on traits. Genetic drift is random allele - frequency change (e.g., due to small population size, random events). Since the change here is due to migration (introduction of new genetic material from another population), it is gene flow.

Answer:

gene flow