Final answer:
Falconer's formula for heritability is the equation that relates environmental variations in genes to the total phenotype variation, while the Hardy-Weinberg equation describes genetic structure under certain conditions.
Step-by-step explanation:
The equation that describes the relationship between the variation in environmental variation in genes and the total variation in phenotype is Falconer's formula for heritability. This formula takes into account both the genetic (heritable) and environmental variance to understand the phenotypic variance in a population. The Hardy-Weinberg equilibrium equation, on the other hand, does not directly address the relationship between environmental variation and phenotype but is crucial for understanding the genetic structure of a population under specific conditions.