Pluto, Eris, Haumea, Ceres, and Makemake are the answers to this question.
They are said to be “denser” than air. what happens is that light slows down when it passes from the less dense air into the denser glass of water. this slowing down the ray of light also causes the ray of light to change directions. it is the change in the speed of the light that causes refraction.
They have evolved into the best length for their environment.
Cutaneous membrane also known as the skin
