A bottleneck event leads to which genetic consequence?

A bottleneck event leads to which genetic consequence?

• A. Decreases allele frequency
• B. Increases mutation rate
• C. Causes immediate speciation
• D. Increases allele diversity

Answer: (A)

A bottleneck dramatically reduces the genetic toolkit of a population. When only a few individuals survive, many of the original alleles are lost simply by chance, and the alleles that remain can shift in frequency. This random loss shrinks genetic diversity and leaves a population with fewer distinct alleles than before. It doesn’t boost mutation rates, isn’t a quick path to speciation, and it certainly doesn’t increase allele diversity.

A bottleneck dramatically reduces the genetic toolkit of a population. When only a few individuals survive, many of the original alleles are lost simply by chance, and the alleles that remain can shift in frequency. This random loss shrinks genetic diversity and leaves a population with fewer distinct alleles than before. It doesn’t boost mutation rates, isn’t a quick path to speciation, and it certainly doesn’t increase allele diversity.