Final answer:
The specific percentage of the heritability of happiness is not given in the provided data, but personality traits with a relation to happiness show more than 50% of heritability. Heritability involves genetic variance and is influenced by multiple factors, including environment and epigenetics.
Step-by-step explanation:
The question pertains to the heritability of happiness based on findings from behavioral genetics research. The Minnesota Study of Twins Reared Apart has contributed significantly to understanding the heritability of personality traits, including happiness.
Heritability is expressed as a percentage and refers to the proportion of variance in a trait attributable to genetic variation among individuals.
While the data provided does not give a specific percentage for the heritability of happiness, heritability estimates for personality traits such as well-being (which can be closely related to happiness) are often reported to be more than 50%.
It is important to recognize that heritability is about the variation in a trait within a given population and does not imply that traits are fixed or determined solely by genes.
Environmental factors, interactions between genes and the environment, and epigenetic factors also play significant roles in shaping an individual's traits and behaviors, including their sense of happiness.