Guide to the study of animal ecology

by Charles C. Adams

1903. Birds in their Relations to Man. pp. 380. Phila. Extensive bibliography on the food of birds.

Wheeler, W. M.

1911. Insect Parasitism and its Peculiarities. Pop. Sci. Mo., Vol. LXXIX, pp. 431-449.

1910. The Effects of Parasitic and Other Kinds of Castration in Insects. Jour. Exp. Zoöl., Vol. VIII, pp. 377-438.

Zacharias, O., and others.

1891. Die Tier- und Pflanzenwelt des Süsswassers. Bd. I, pp. 380; Bd. II, pp. 369. Leipzig.

Contains several valuable and suggestive papers on the general biological relations of fresh-water plants and animals.

2. The Dynamic Relations of Aggregations and Associations, with Special Reference to Animal Associations

“A group or association of animals or plants is like a single organism in the fact that it brings to bear upon the outer world only the surplus of forces remaining after all conflicts interior to itself have been adjusted. Whatever expenditure of energy is necessary to maintain the existing internal balance amounts to so much power locked up, and rendered unavailable for external use. In many groups this latent energy is so considerable and is liable to such fluctuations, that a knowledge of its amounts and kinds, and of the laws governing its distribution, is extremely important to one interested in measuring or foreseeing the sum and character of the outward-tending activities of the class.”

—S. A. Forbes (1883).