Rahma took these notes on a process involving the movement of molecules, but she forgot to title them. –Causes molecules to move until they are evenly distributed
–Moves from high concentration to low concentration
–Has no need for added energy
–Can occur with or without a membrane being present

Which of the following best describes the expensive tissue hypothesis? brains require more energy, so the gut had to be reduced, and larger brains and tool use led to higher quality diets. increasing body size means that homo neanderthalensis had to include more fat in its diet. brains require more energy, so the gut had to be reduced as brains got bigger. brains require more fat, so the gastrointestinal viscera (gut) had to expand, and hands were needed to acquire more food.