In the Founder Effect, a small group of organisms from the original population become isolated and begin a new population. Since there are very few of them, there will be a lot of inbreeding and thus the spectrum of genotypes will be different from and much more homogeneous than the original population. Genetic drift has thus occurred. An example is in certain populations of Amish people and at Lake ____________ in South America where Nancy Wexler has studied the high occurrence of Huntington's Disease.
In the Bottleneck Effect, most of the original population gets killed off, leaving only a few to repopulate the area. For the same reasons as above, the new population will exhibit genetic drift. An example of this is in the cheetah in Africa. Most of them were killed off by hunters, so that all cheetahs are now very closely related genetically. One of the consequences is that a large percent of cheetahs born in the wild do not survive due to multiple genetic defects.
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