They had to change they way they live which is quite difficult it is like you going to a new school in a new state and not being used to anyone
E Bipedalism is least important because two feet. The others are
important to have a brain, reproduction, vision, and motion movment.
Cell walls are made of cellulose in (Plant) cells.
The concept of internal human stability which is also a central concept of human physiology which you're talking about/asking a question about would be homeostasis. By a homeostatis we're talking about a very narrow interval of functioning in which people function best and have optimal working efficiency.
The DNA can become a double strand again.
