Geological Biology

GEOLOGICAL BIOLOGY.

CHAPTER I.

THE HISTORY OF ORGANISMS. ITS SCOPE AND
IMPORTANCE.

Man an Organism among Organisms.-Man has been very slow to grasp the fact that he is an organism among organisms. Darwin was the first to speak with such loud emphasis as to thoroughly rouse the world to an appreciation of the very intimate relationship man bears to the whole series of organic forms of not only present but all past time. We are apt to be offended by the bold statement that man is descended from the monkeys, but, without insisting upon the truth of this specific statement, the investigations of modern science have demonstrated beyond controversy that the same. conditions of affinity and relationship which lead to the classification of animals into species, genera, or classes, and as connected with each other by direct genetic descent, apply to man as one of the organisms.

For want of a better name this relationship of man to other organisms may be called his natural-history relationship. Man is an organism among organisms, and it is this fact that lifts the history of organisms out of the field of simple morphological or physiological sciences into a place of direct human interest. Man's origin and history is intimately associated with the origin and history of other living beings in the world.

Not only is there human interest in the subject of the history of organisms, but because of this interest there is a de

mand for discussion of the facts themselves from a special point of view.

The naturalist takes interest in the form and functions of individual organisms from a scientific point of view; they are to him objects of interest in themselves. He classifies and arranges them as favorite objects of knowledge. But the general student, the active thinker, the busy worker in human. affairs finds the details of such studies irrelevant, and to him. the vital interest is in the questions concerning the relations of organisms to the past and to himself.

More than this, the deepest interest of all attaches to the philosophy which is involved in the proposition that man is not so distinct from the dumb organic world around him as was up to a few years ago universally believed to be the case.

History of Organisms and Man's Relationship to Living Things. —If man has arisen from organisms that were not men; if the machinery of his vital organization is represented in less complex form in other animals; if he may find his functions in operation in simpler forms of life, and separated into their elements in lower types, then he has in the organic world a field of study of the greatest interest, which he cannot neglect without ignoring knowledge that is, in a literal sense, vital to his best interests as a man.

The study of the laws of organisms, their relations to each other and to the conditions of environment, their antiquity, their history, and the nature of those laws of adjustment which are suggested by the words heredity and descent, variability, natural and unfavorable habitat, struggle for existence, adaptation to environment, evolution, and many others which have arisen within the last fifty years, is of more importance than we ordinarily attach to the study of the curiosities of natural history.

The Discussion not from the Zoological and Botanical Side.-The approach to the study of organisms, from the zoological or botanical side, presents great difficulty in the very immensity of the subject. When we attempt to analyze the characters of a single animal, to classify animals and describe them, the mere mass of detail-the abundance of the characters to be distinguished-removes the subject from a place in a gen

Such a treatment of organ

eral course of liberal education. isms as may be sufficient for the illustration of their history does not necessarily enter into an analysis of the structural characters of any particular species. Hence, from the point of view of a technical course of study in biology, this treatise will seem quite superficial.

In defining

The Geological Aspect of the History of Organisms. On the other hand, there are characters distinguishing groups of organisms, evidence of which may be preserved in the rocks, which are of far greater importance than the specific details in indicating the relationship organisms bear to each other, to the conditions in which they have lived, and to the place they have occupied in the history of the life of the globe. Such characters are those which will concern us here. our topic as geological biology, we are not proposing to investigate the anatomical organs and tissues of which particular animals are made, but to review the facts and theories which have led to the belief that each living animal and plant is but the last of a long line of organisms whose remains can be recognized in more or less perfect fossils, and whose varying characters can be traced back into the immense antiquity of geological time.

Geological History not a Repetition of Like Events, but a Progressive Change of Phenomena.—If there were only repetition of the same things, this would not constitute history. If different things have succeeded each other, to ascertain the relationship borne by those that follow to those that preceded them becomes an important problem. We do not, at the outset, assume to explain the causes, but geology makes the fact clear that there has been a very elaborate history of the organisms that have lived on the earth. The question we propose to answer is, "What are the prominent laws expressed in this history?"

The geologist observes that there has been a history for the earth itself: the rocks, as geological formations; the lands, as parts of the crust above the surface of the ocean; the surface of the earth, as a whole, in all its complexity-all these have come to be what they are through innumerable changes. The geological conditions in the past have been associated

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Geological Biology: An Introduction to the Geological History of Organisms