Final answer:
Small populations are highly susceptible to genetic drift because the loss of even a single individual can lead to a significant change in the population's gene pool. Larger populations are more genetically stable against random events, as they have greater genetic diversity.
Step-by-step explanation:
How Small Populations Are Affected by Genetic Drift Small populations are more vulnerable to the effects of genetic drift compared to larger populations. This occurs because genetic drift is accentuated in small populations due to the founder effect and the bottleneck effect, both of which reduce genetic variation and thus, the capacity for a population to adapt to environmental changes. For instance, if one individual with unique alleles dies without reproducing in a small population, those alleles will be completely lost, greatly impacting the population's genetic structure. This is not the case in larger populations where the loss of a single individual has a statistically smaller impact on the gene pool.
The flow of alleles in and out of a population, known as gene flow, can also alter genetic composition, especially when new individuals migrate into a population. On the other hand, genetic drift can be affected by differential survival and reproduction, as illustrated by the example of white rabbits being more visible to predators, therefore being eaten more often and decreasing the allele frequency for white fur within the population.
In summary, genetic drift effects can lead to a significant change in the population's genetic makeup. This makes small populations particularly susceptible to changes in allele frequencies due to random events, and less stable over time compared to larger populations with a more diverse and stable gene pool.