Introduction
Hello and welcome topic 7.11 of AP Biology: Variations in Populations! This lesson reviews genetic diversity and how it affects a population's resilience to different selective pressures. Everything you’ll learn here is similar to previous topics and this lesson mainly serves to string everything together.
Genetic Diversity
Genetic diversity is the variety of different genetic traits (or genes) within a single species or population. A population's ability to respond to environmental changes is dependent on its genetic diversity. Populations with higher genetic diversity are more likely to adapt and be resilient to environmental changes, as they have a higher chance of having individuals that can withstand these environmental pressures. However, species with low genetic diversity are at a much higher risk of decline and/or extinction.
However, alleles that are advantageous in one environmental condition may be deleterious in another due to different selective pressures. For example, returning to the bear analogy, a polar bear would have an advantage living in the Arctic but not in the forest since it would be unable to camouflage.
Ultimately, genetic diversity impacts a population’s resilience to different selective pressures and its ability to respond to environmental changes.