AP BIOLOGY

Detailed explanation-1: -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-2: -Genetic drift is the change in frequency of an existing gene variant in the population due to random chance. Genetic drift may cause gene variants to disappear completely and thereby reduce genetic variation. It could also cause initially rare alleles to become much more frequent, and even fixed.

Detailed explanation-3: -Genetic drift is common after population bottlenecks, which are events that drastically decrease the size of a population. In these cases, genetic drift can result in the loss of rare alleles and decrease the gene pool.

Detailed explanation-4: -A genetic bottleneck occurs when a population is greatly reduced in size. The bottleneck limits the genetic diversity of. the species because only a small part of the original population survives.

Detailed explanation-5: -Genetic drift can cause big losses of genetic variation for small populations. Population bottlenecks occur when a population’s size is reduced for at least one generation.