<p>Genetic Drift i cant understand it !!! can any one help me ??
examples of genetic drift is :
A.Bottleneck
B.Founder effect what is mean Both ???</p>
<p>It’s been a long time since I’ve taken bio, but this is my best recalling:</p>
<p>Genetic drift is change in a population due to random variation. Unlike natural selection, it doesn’t have some force behind it; just random chance. It only happens with small populations because in larger ones the variation cancels out. Genetic drift can reduce genetic variety.</p>
<p>Bottleneck - A disaster occurs and a population is reduced to a very small size. Genetic drift will occur because population size is lowered. Genetic variety is also clearly lowered.</p>
<p>Founder effect - A small population founds a much larger one, such as a group of settlers starting a colony. The genetic properties of the founders will be disproportionally represented in their offspring. For example, if several of the founders of a colony have hereditary blindness, a few generations down the road the colony will have many more blind people than surrounding colonies will.</p>