Which of the following is the best example of gene flow?
a. A small population of humans colonizes a newly formed island.
b. A fire drastically reduces the size of a white-tailed deer population. The remaining individuals spread out throughout the remaining forest.
c. An earthquake results in the formation of a canyon, splitting a population of toads apart.
d. Wind blows pollen from one population of plants to another and cross-fertilization occurs.
Answer: D