1. Baird, D. T., “Reproductive Hormones,” in C. R. Austin and R. V. Short, eds., Reproduction in Mammals: 3 Hormones in Reproduction (Cambridge, England: Cambridge University Press, 1972).
2. Blount, R. F., “The Effects of Heteroplastic Hypophyseal Grafts upon the Axolotl, Ambystoma mexicana,” Jour. Exp. Zool.
113 (1950), p. 717.
3. Darwin, Charles, On the Origin of Species by Natural Selection, or the Preservation of Favored Races in the Struggle for Life (1859).
4. Darwin, Charles, The Descent of Man and Selection in Relation to Sex (1871), reprinted from the English edition (New York: A. L. Burt Company, 1971).
5. Dimond, Stuart J., The Social Behavior of Animals (New York: Harper & Row, 1970).