Arizona State University (ASU) BIO 345 Evolution Exam 2 Practice

The Hardy-Weinberg principle describes the genetic variation in a population that is in equilibrium, where allele and genotype frequencies remain constant over generations in a non-evolving population. This principle establishes a mathematical model that predicts how gene frequencies will remain stable in the absence of evolutionary influences, such as natural selection, mutation, migration, genetic drift, or non-random mating. The conditions for a population to be in Hardy-Weinberg equilibrium include a large breeding population, random mating, no migration, no mutations, and no selection. When these conditions are met, allele frequencies can be calculated using the Hardy-Weinberg equation, which allows for predictions about genetic variation within the population. Thus, the correct answer highlights an essential concept in population genetics related to equilibrium, contrasting it with situations where external factors influence gene frequencies.