ON A DIFFERENCE IN THE METABOLISM OF THE
SEXES.
IT is increasingly apparent that all sociological manifestations proceed from physiological conditions. The variables entering into social consciousness and activity technology, ceremonial, religion, jurisprudence, politics, the arts and professions, trade and commerce have confessedly either a primary or a second- ary connection with the struggle for food. Reproduction, a utilization of surplus nutrition, is also obviously in the closest possible relation with food, and the evidence here detailed is designed to show that the determination of sex is a chemical matter, maleness and femaleness being solely expressions of a difference of attitude toward food. If such a connection can be traced between sex and nutrition it will afford a starting point for a study of the comparative psychology of the two sexes and for the investigation of the social meaning of sex.
A grand difference between plant and animal life lies in the fact that the plant is concerned chiefly with storing energy, and the animal with consuming it. The plant by a very slow process converts lifeless into living matter, expending little energy and living at a profit. The animal is unable to change lifeless into living matter, but has developed organs of locomotion, ingestion, and digestion which enable it to prey upon the plant world and upon other animal forms, and in contrast with plant life it lives at a loss of energy. Expressed in biological formula, the habit of the plant is predominantly anabolic, that of the animal predom- inantly katabolic. Certain biologists, limiting their attention in the main to the lower forms of life, have maintained very plau- sibly that males are more katabolic than females, and that male- ness is the product of influences tending to produce a katabolic habit of body. 1 If this assumption is correct, maleness and . KDDES and THOMSON, The Evolution of Sex, 1889, have presented this view in an
