AP BIOLOGY

Detailed explanation-1: -Demographic bottlenecks generally reduce genetic diversity through more intense genetic drift, but their net effect may vary along the genome due to the random nature of genetic drift and to local effects of recombination, mutation, and selection.

Detailed explanation-2: -Once it begins, genetic drift will continue until the involved allele is either lost by a population or until it is the only allele present in a population at a particular locus. Both possibilities decrease the genetic diversity of a population.

Detailed explanation-3: -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-4: -Small populations tend to lose genetic diversity more quickly than large populations due to stochastic sampling error (i.e., genetic drift). This is because some versions of a gene can be lost due to random chance, and this is more likely to occur when populations are small.