Answer:
Some genes produces variable traits depending on environmental conditions
Step-by-step explanation:
The interaction between some genes and environments confers on individuals different degrees of susceptibility in the appearance of a certain characteristic or in the expression of some variable traits. The trait appears in individuals who have reached a certain threshold, thus the variability in phenotypic expression could be related to the greater or lesser number of predisposing genes in each individual. The differential expression of genes depending on the environment is called the reaction norm, and it refers to genes that can be expressed in a different way in different individuals, depending on the environment in which those individuals develop. The norm of reaction is the set of pathways that a genotype can follow, in all favorable and unfavorable environments, until giving rise to the various possible phenotypes.