AP BIOLOGY

Detailed explanation-1: -The bottleneck effect occurs when a population’s size is reduced for at least one generation. Undergoing a bottleneck can greatly reduce the genetic variation in a population, leaving it more susceptible to extinction if it is unable to adapt to climactic changes or changes in resource availablility.

Detailed explanation-2: -Populations generate genetic variation over time, which can be specifically reduced by selection or stochastically reduced by genetic bottlenecks. After a bottleneck, a limited number of randomly selected individuals create a founding population, resulting in genetic drift.

Detailed explanation-3: -The bottleneck effect is an extreme example of genetic drift that happens when the size of a population is severely reduced. Events like natural disasters (earthquakes, floods, fires) can decimate a population, killing most individuals and leaving behind a small, random assortment of survivors.

Detailed explanation-4: -A genetic bottleneck occurs when a population is greatly reduced in size, limiting the genetic diversity of the species. Scientists believe cheetahs (Acinonyx jubatus) have already survived at least two genetic bottleneck events.