Gene flow refers to the transfer of genetic material from one population to another. This can occur when individuals from one population migrate and join another population, bringing their genes with them. This process can introduce new alleles into the population, increasing genetic diversity.
The correct statement that best describes what happens in gene flow is:
c) New individuals that join a population contribute
When new individuals join a population, they bring their own unique set of genes. These genes can then be passed on to the next generation, thereby altering the gene pool of the population. This is a key mechanism of evolution, as it can lead to changes in the genetic makeup of a population over time.
In contrast, crossing over (option a) is a process that occurs during meiosis, where homologous chromosomes exchange genetic material, creating new combinations of alleles. This is not related to gene flow. Chance events (option b) that alter a population’s gene pool are typically associated with genetic drift, not gene flow.