Final answer:
The founder effect and population bottlenecks both influence a population's genetic makeup as a result of genetic drift. The bottleneck effect occurs after a disaster reduces population size and variability, while the founder effect is when a new population starts from a small group, potentially with different allele frequencies than the original.
Step-by-step explanation:
The founder effect and population bottlenecks are two phenomena that can lead to significant changes in a population's genetic structure due to genetic drift. Both result in reduced genetic diversity, but they occur under different circumstances and have different outcomes.
The bottleneck effect happens when a population's size is significantly reduced due to an event such as a natural disaster, leading to a random sampling of alleles which can dramatically change the genetic makeup. This can result in the loss of genetic variation and potentially harmful genetic structures due to inbreeding depression as the population recovers.
Conversely, the founder effect occurs when a small group of individuals leaves a larger population to establish a new one. The new population's genetic structure may significantly differ from the original due to the limited genetic variance of the founders. This can introduce new alleles into the population or increase the frequency of existing ones, which may increase certain genetic disorders due to a non-random sample of alleles from the original population.