Why are the Gene pools of small populations reduced compared to those of larger populations
The gene pools of small populations are reduced compared to those of larger populations because of genetic drift, inbreeding, and reduced genetic diversity.
1. Genetic drift: In small populations, random events such as natural disasters, disease outbreaks, or human activities can lead to the loss of certain alleles (gene variants) from the gene pool. Due to the small size of the population, these random events can have a greater impact and result in a reduction in genetic diversity.
2. Inbreeding: In small populations, individuals are more likely to breed with closely related individuals, leading to an increase in the frequency of harmful recessive alleles. Inbreeding can result in the expression of deleterious traits and a decrease in overall fitness of the population.
3. Reduced genetic diversity: Small populations have a limited number of individuals, which means there are fewer alleles available for natural selection to act on. This can result in a reduced ability to adapt to changing environments and an increased susceptibility to diseases or other threats.
Overall, the combination of genetic drift, inbreeding, and reduced genetic diversity in small populations can lead to a decrease in the overall fitness and viability of the population, making them more vulnerable to extinction.