AP BIOLOGY

Detailed explanation-1: -Genetic drift can have major effects when a population is sharply reduced in size by a natural disaster (bottleneck effect) or when a small group splits off from the main population to found a colony (founder effect).

Detailed explanation-2: -Definition. Founder effect refers to the phenomenon which occurs when a small group of individuals becomes isolated from a large population while the bottleneck effect refers to the phenomenon which occurs when a population rapidly decreases in size.

Detailed explanation-3: -The fish in the flash flood were separated from the main population and subsequently established a new population in the nearby lake. This is an example of the founder effect. The drought lake is the best example of the Bottleneck effect because the event was random and the survivors lived due to random chance.

Detailed explanation-4: -The founder effect principle was developed by Mayr (1954). It is based on the assumption that reproductive isolation from the parent species can evolve rapidly in a population established by a very small number of founding individuals (i.e., 2–10).