Page:Popular Science Monthly Volume 66.djvu/233

Rh paleontologia sine geologic. With other physical sciences paleontology is hardly less intimate; from the physicist it demands time for the evolution of successive waves of organisms, from the geographer it demands continental connections or even whole continents for the passage of land animals and plants. As with geology, what it receives it is ever ready to return in gifts; the new branch of geography, for example, entitled paleogeography, appeals quite as often to the paleontologist as to the geologist for its data.

Naturally the central thought of paleontology as biology is the origin of fitness as the property which above all others distinguishes the living from the non-living. Here the paleontologist enjoys the peculiar advantage of being present at the birth of new characters and watching the course of their development; and to this advantage is attached the peculiar responsibility of observing the birth and course of development of such characters with the utmost accuracy and a mind free from prejudices in favor of any particular hypothesis, with full acquaintance with the phenomena of evolution as they present themselves to the zoologist, the botanist and the experimentalist, and with the philosophical temper which will put every hypothesis to the test of every fact. The laughing remark of Cope on seeing a newly discovered specimen which controverted one of his hypotheses, 'if no one were watching I should be glad to throw that fossil out of the window,' has a serious reality in our often unconscious protection of our own opinions.

The birth of new characters is the crucial point in the origin of fitness. With Darwin himself, with Cope, with Bateson, we do not regard the Darwinian law of selection as the creative or birth factor; by its very terms it operates after there is something of value to select. Forgetting this distinction, some naturalists are so blind as to fail to see that selection is still the supreme factor in evolution in the sense that it produces the most grand and sweeping results as well as the most inconspicuous results in the organic world. Certain of the creative factors can not be seen at all by paleontologists; others, in my opinion, can not be seen by zoologists.

Before looking further into the creation of fitness, let us clear away another misconception, which happens to be of paleontological origin, although paleontologists are not responsible for it. It concerns the history of one of the great theories of the day. Many years ago, Waagen, a German paleontologist, observed that the varieties or minor changes in time (chronological varieties) differ from varieties in space (geographical varieties); that the latter have a variable value and are of small systematic importance, while the former are very constant and.