Question

Describe the FIVE model assumptions of the Hardy-Weinberg theorem, AND explain why each is a violation and how it can lead to evolutionary change.

Answer 1

The Hardy-Weinberg model outlines five crucial assumptions for a population to maintain genetic equilibrium. Violating these assumptions, such as mutations, gene flow, genetic drift, non-random mating, or natural selection, results in evolutionary change by altering allele frequencies and, consequently, genotype frequencies within the population.

Step-by-step explanation:

The Hardy-Weinberg model is pivotal in understanding population genetics and assumes genetic equilibrium is maintained in a population if five conditions are met, which comprise:

1. No mutations
2. No gene flow or migration
3. A large population size to prevent genetic drift
4. Random mating to ensure equal genetic contribution
5. No natural selection allowing for survival of all genetic variants

Each assumption is critical, and violation of any can lead to evolutionary change:

• Mutations can introduce new alleles, altering allele frequencies.
• Gene flow can alter allele frequencies when individuals migrate into or out of a population.
• Genetic drift can significantly impact allele frequencies in small populations due to random chance events.
• Non-random mating can result in certain alleles being passed on more frequently, skewing genotype frequencies.
• Natural selection can affect allele frequencies if certain genotypes confer a survival advantage.

When the frequencies of alleles or genotypes deviate from those expected under Hardy-Weinberg equilibrium, we can infer that the population is not static and is indeed evolving under the influence of these evolutionary forces.