Which statement best describes the greenhouse effect?
A: It is a process by which plants are able to grow well in a warm, enclosed structure.
B: It is a process by which greenhouse gases block the sun’s light to penetrate the atmosphere.
C: It is a process by which greenhouse gases allow the sun’s light to penetrate the atmosphere but stop the heat from escaping.
D: It is a process by which prevailing winds bring moisture to the land, to the prevailing wind direction.

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.