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During times of poverty or famine, people are often faced with a shortage of food.

Maxwell is studying how the energy in food is transferred from one trophic level to another in a food pyramid. He learns that by decreasing the number of trophic levels in a food pyramid, less energy is lost to the environment as heat.

Maxwell concludes that in times of food shortage humans should replace the
animal products
in their diets with
plant products
in order to decrease the number of trophic levels in their food pyramid.