WANI Dictionary

Bottleneck effect

Bottleneck effect is the reduction of genetic diversity caused by massive death of members in a population.

After disaster that kills most members of a populaion, survivor's genetic structures become dominant in the population.

Definitions in the literature

• bottleneck: Reduction in population size so severe that it reduces genetic diversity [1].
• Natural events, such as an earthquake disaster that kills—at random—a large portion of the population, can magnify genetic drift. Known as the bottleneck effect, it results in suddenly wiping out a large portion of the genome (Figure 19.5). At once, the survivors' genetic structure becomes the entire population's genetic structure, which may be very different from the pre-disaster population [2].