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?

No.

"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.

To answer this question, we need to consider two main factors: energy efficiency and environmental impact.

1. Energy efficiency: It is true that producing animal-based foods and goods requires significantly more energy compared to plant-based options. This is because animals at the top of the food chain like cows, pigs, and chickens need to be fed large amounts of plant-based feed to grow. This process leads to energy loss at each trophic level, as energy is transferred from plants to animals. So, consuming products closer to the bottom of the food chain, such as fruits, vegetables, grains, and legumes, can generally be considered more energy-efficient.

2. Environmental impact: Animal agriculture is a major contributor to greenhouse gas emissions, deforestation, water pollution, and biodiversity loss. The production of animal-based foods requires significant amounts of land, water, and fossil fuels. In contrast, plant-based options have a lower environmental footprint. Consuming products lower on the food chain reduces the demand for animal-based products, helping to alleviate these environmental impacts.

Considering these points, it can be argued that shifting towards a diet that includes more plant-based options can be more energy-efficient and environmentally sustainable. However, it is important to note that dietary choices are influenced by various factors, including cultural, social, and personal preferences. Making small changes, like incorporating more plant-based meals, can still have a positive impact on energy efficiency and the environment.