PART III. Animal Ecology

ANIMAL ECOLOGY

XXIX.--THE STRUGGLE FOR EXISTENCE, ADAPTATION, AND SPECIES-FORMING.

The multiplication and crowding of animals, 404.--The struggle for existence, 406.--Variation and natural selection, 406.--Adaptation and adjustment to surroundings, 407.--Species forming, 408.--Artificial selection, 409.

XXX.--SOCIAL AND COMMUNAL LIFE, COMMENSALISM, AND PARASITISM.

Social life and gregariousness, 410.--Communal life, 411.--Commensalism, 413.--Parasitism, 415.

XXXI.--COLOR AND PROTECTIVE RESEMBLANCES.

Use of color, 424.--General, variable, and special protective resemblance, 426.--Warning colors, terrifying appearances, and mimicry, 430.--Alluring coloration, 433.

XXXII.--THE DISTRIBUTION OF ANIMALS.

Geographical distribution, 435.--Laws of distribution, 437.--Modes of migration and distribution, 437.--Barriers to distribution, 438.--Faunæ and zoogeographic areas, 440.--Habitat and species, 441.--Species-extinguishing and species-forming, 442.

APPENDICES

EQUIPMENT AND METHODS