 I know that a lot of students think that found effect and bottleneck are the same because they both result in genetic drift, which is the random change in allele frequencies from generation to generation. Although both modes of genetic drift ultimately have the same result, the two processes of how they came to be are completely different. Bottleneck occurs when a population is reduced down to a few individuals, for example, due to a natural disaster like a flood. Something that helps me to remember is to picture a bottle and visualize how the neck gets smaller and smaller as you move from the widest part of the bottle to the top. Meanwhile, found effect occurs when a small group leaves the main population to go and establish a new population. And remember, although the focus is now on the new population, the mainland population still exists with all of the initial genetic information. As we just saw, both processes lead to genetic drift, but how we got there given each process was very different. I hope that this video helped to clarify the topic of bottleneck versus found effect. Now, here's a short quiz with some real-world examples to solidify your understanding.