Daiyo, a behavioral geneticist, is studying the interaction of heredity and environment. when he looks at monozygotic twins, what will he probably see in their phenotypes? their genotypes will cause them to have very different phenotypes. they will have exactly the same phenotype. their genotypes will predispose them toward certain traits, but their environments influence whether those traits are expressed in their phenotypes. their environments will cause them to have very different phenotypes.