Question

Which significant change can occur to a small population as a result of genetic drift?
The Hardy-Weinberg equilibrium will not equal 1.
Recessive traits always become dominant.
Large changes in allele frequencies can occur in a short time.
New individuals add their genes to the gene pool.

Answer 1

Genetic drift arises when a genetic change is passed forward through the generations but is not expressed as part of the phenotype, so does not come under selective pressure from the environment. A shift in a gene pool’s content can be genetic drift, caused by random fluctuations in allele frequencies due to accident & chance losses removing one allele more than another. This impact is most profound on small populations => founder effect

In small initial populations genetic drift can have enormous impact on the population's phenotype whether the entire genotype is under selective pressure or not. The small populatin can have so few coppies o alleles that loss of a few individuals removes those variations from the gene pool. In large populations the random changes in allelic traits generally cancel out statistically. Losses of individuals by random means will not selectively remove any single expressed trait or nonphenotypic allele.