Final answer:
The false statement about genetic drift is that it cannot affect the frequency of traits with a visible phenotype. Genetic drift, a random evolutionary process, can influence visible traits and is more potent in small populations. It can be caused by accidental deaths, disasters, or mutations...
Step-by-step explanation:
The statement that is false about genetic drift is: c. genetic drift cannot affect the frequency of traits with a visible phenotype. This statement is incorrect because genetic drift can indeed impact the frequency of visible traits. Genetic drift is a random process that can lead to changes in allele frequencies in a population regardless of whether they have visible or invisible phenotypes.
Causes of genetic drift include random events such as accidental deaths, natural disasters, and the effects of populations being small, like the bottleneck and founder effects. When disasters strike indiscriminately, they can reduce genetic variation regardless of the genotypes' adaptiveness, leading to different allele frequencies. In small populations, which are more susceptible to genetic drift, random events tend to have a greater influence on allele frequencies because each individual represents a larger fraction of the total gene pool.
Examples illustrating genetic drift include a population in which a mutation introduces a new allele, changing the gene pool, or situations where allele frequencies shift by chance over generations, potentially leading to the fixation or loss of alleles. Whether due to the influx of new alleles through mutation or chance fluctuations, genetic drift is a significant evolutionary mechanism, along with mutation and gene flow, and can introduce new genetic variation into a population.