Question

As allele frequencies in a finite population drift toward fixation or loss, what happens to the frequency of heterozygotes in the population?

1) Heterozygosity doesn't change
2) Heterozygosity decreases
3) Heterozygosity increases
4) Cannot say because heterozygosity and drift are unrelated

Answer 1

Genetic drift can lead to the decrease in the frequency of heterozygotes in a population over time.

Step-by-step explanation:

Genetic drift is a phenomenon where allele frequencies in a population change randomly with no advantage to the population over existing allele frequencies. As a result of genetic drift, the frequency of heterozygotes in the population decreases over time.

This is because genetic drift can lead to the fixation or loss of alleles in a population. When an allele becomes fixed, it means that all individuals in the population carry that allele. Conversely, when an allele is lost, it means that it is no longer present in the population.

As alleles drift toward fixation or loss, the number of heterozygotes decreases because individuals with heterozygous genotypes can only retain their heterozygosity if both alleles are maintained in the population. If one allele drifts to fixation or is lost, then heterozygotes cannot be formed.