Vegetarianism. Why would it be more efficient (in terms of ecological energetics

Vegetarianism.
Why would it be more efficient (in terms of ecological energetics) for people to be vegetarian? Discuss your answer with reference to the pyramid-shaped structure of ecological productivity. Create a diagram to illustrate your answer.
Also, please list additional reasons why vegetarians have a smaller “ecological footprint” associated with their feeding habits.
The written portion of this questions should be about 3 paragraphs.