posted by April .
Considering the amount of energy required to produce animal-based foods and goods, should humans change their habits so they consume products closer to the bottom of the food chain because it is more efficient?
"More efficent" depends on what you mean by efficient. The food value of an animal is concentrated, so humans eating it are "more efficent" eaters. Now considering Solar energy, it might be more efficent not to eat animals. Humans shifted from grasses and nuts, for the most part, many thousands of years ago. Grazing is hard work.