Bottleneck effect

 Due to the rapid reduce of the population, it changes the gene distribution.

 

How it works

The bottleneck effect occurs when a population’s size decreases rapidly due to starvation, disease, human activities and natural disasters such as severe weather. Due to those reasons, we have less alleles and the gene pool has lost its diversity. What I mean by losing its diversity is the gene pool that used to have different variations now have less variation and may not be able to adapt the new selection pressures.  

Bottleneck effect refers to the actual bottle neck. Since there is a narrow path, there is a random possibility of alleles coming out. So, the diversity of the gene pool can change due to the bottleneck effect.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Example 

The famous example of the bottleneck effect of the animal is a Northern elephant seal. Northern elephant seal is good for making long life and natural oil, and some for storage of food. One adult elephant seal can produce about 25 gallons of oil, so many hunters are targeting the male elephant seals. around 1880s, too much of hunting lead to the extinction of northern elephant seal. Bottleneck effect can be caused by human, and this shows the great example of it. The random northern elephant seals were killed and reduced their population.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The Mexican government had to design an island called “Guadalupe Island” to wait for the recovery of the Northern elephant seal population. When the Guadalupe island was designed for the northern elephant seals, there were only about 100, but they could expand the new population and genetic pool. Even now, the northern elephant seal population is increasing and living today.