A recent critique of ecological tqeory and the protein focused upon some general features of human nutrition and the cultural biases which have led to an overemphasis on the role of animal protein (Diener, Moore, and Mutaw 1980). In this paper, authors expand upon that general critique and develop an alternative, evolutionary perspective upon problems of human nutrition. They employ the relative importance of plant and animal foods in Mesoamerica as a useful example.