The American Journal of Science, Vol. 6 (Classic Reprint)

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Excerpt from The American Journal of Science, Vol. 6Before undertaking any general or special examination of the life histories and interpretation of spinose organisms, it is desirable to consider brie¿y some of the biogenetic principles which are considered to bear directly on the problems here under discussion.First among these is the law of variation or change, which is so generally recognized as to require but the briefest restate ment.The organic as well as the inorganic world is subject to all the forces of nature, internal and external, molecular and molar, and even a partial stability is gained only through a regulated adjustment. In organisms, this change is momentary and persistent, while in most inorganic substances, it is slow and intermittent. The results of this continual readjustment constitute modification, which may be progressive or regressive, continuous or discontinuous (in the sense of accelerated, uni form, or retarded). They are everywhere present and the causes always operative. Throughout life, the individual chan es, and in addition varies from all other individuals. The fami y, also, changes with time, and likewise differs from other families. Variation is everywhere present. Moreover, it is generally accepted, and is so taken here, that, in its results, this variation is not haphazard, but is normally in accordance with certain demands or in harmony with certain surroundings. Whether an organism itself tends to vary in all directions, or is chie¿y subject to modifications from external forces, does not alter the preceding statement.Cope has considered variation as either physico-chemical (molecular) or mechanical (molar). The in¿uence of the first is known as physiogenesis and Of the second as kinetogenesis. In the animal kingdom, the potency Of kinetogenesis is greater as an efficient cause of evolution, while in the vegetable king dom, physiogenesis is apparently of more importance.The tendency Of variation is always in the direction of the establishment Of an equilibrium between the organism and its environment. However, the laws of the development Of the earth preclude the possibility of a constant environment, and therefore a perfect, permanent, and uniform equilibrium between life and surroundings is unattainable.About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully, any imperfections that remain are intentionally left to preserve the state of such historical works.