Complex sentence: Giving merit to the hypothesis that constraints on physiological processes at the cellular level account for temperature-mediated body size, studies have also shown that "S. stercoraria" body size varies via gene-by-environment interactions.
Split into simpler sentences: Giving merit to the hypothesis that constraints on physiological processes at the cellular level account for temperature-mediated body size. Studies have also shown S. stercoraria body sizes varies via gene-by-environment interactions.