Why are identical wins more similar than brothers and sisters?

Identical twins share 100% of their genetic material, leading to more similar physical traits, behaviors, and predispositions compared to siblings who share only about 50% of their genes. This genetic similarity contributes to greater likeness in personality, interests, and even health conditions. In contrast, brothers and sisters, while they may have some shared traits, often exhibit more variability due to their different combinations of inherited genes and environmental influences. Thus, the closer genetic relationship of identical twins results in a higher degree of similarity than that between siblings.