A Textbook of Botany for Colleges and Universities, Vol. 1 (Classic Reprint)

Tlie scope of ecology. Ecology is a science in its beginnings. Already it has a great body of data and theories whose validity is more or less established, but whose systematic organization scarcely has been attempted. Nor is it possible as yet to mark out its limits, for it overlaps to a greater or less degree every other field of biology, and of physiography and geology as well. Speaking broadly, ecology considers organisms in relation to their environment. Somewhat more precisely, ecology is that phase of biology that endeavors to explain the origin, variation, and r61e of plant or animal structures, and the origin and variation of plant or animal associations. Plant ecology has a twofold aspect: the one considers the individual organism and its component parts as related to environment; this, since it overlaps morphology and physiology, may be called morphological and physiological ecology, or the ecology of plant structure and behavior. The other aspect considers plants en masse as related to soil and climate; this, since it overlaps physiography, may be called physiographic ecology or the ecology of vegetation. Morphological and physiological ecology consider the same materials as do morphology and physiology, but largely from a different point of view. Morphology deals with structure and physiology with behavior, whereas ecology relates both structure and behavior to external conditions, paying attention chiefly to the cause and the significance of environmental variations. Morphology and physiology are essentially laboratory sciences, while ecology is in the main a science of the field, treating organisms as they grow in nature. Since ecology overlaps various sciences, it is less a simple science than a science complex; its adequate study presupposes a foundation in the basic principles of physics, chemistry, morphology, and physiology, Recently prop
(Typographical errors above are due to OCR software and don't occur in the book.)