A century of science in America

by Unknown

As a leader in science, a teacher and administrator, Professor Osborn’s rank is high among the leading vertebratists. He is remarkably successful in his choice of assistants and in stimulating them in their productiveness so that their combined results form a very considerable share of the later literature in America.

The ninth decade ushered in the work of a valuable group of students, of whom John Bell Hatcher should be mentioned in particular, as his work is done. Graduate of Yale in 1884, he spent a number of years assisting his teacher, Professor Marsh, mainly in the field, collecting during that time, either for Yale or for the United States Geological Survey, an enormous amount of very fine material, especially from the West, although he also collected in the older Tertiary and Potomac beds near Washington. In the West he secured no fewer than 105 titanothere skulls, explored the Tertiary, Judith River, and Lance formations, collected and in fact virtually discovered the remains of the Cretaceous mammals and of the horned dinosaurs which he was later privileged to describe. He then (1893) went to Princeton, which he served for seven years, his principal work being explorations in Patagonia for the E. and M. Museum, one direct result of which was the publication of a large quarto on the narrative of the expedition and the geography and ethnography of the region. Going to the Carnegie Museum in Pittsburgh in 1900, Hatcher carried forward the work of exploration and collecting begun for that institution by Wortman, and as a partial result prepared many papers, the principal ones being memoirs on the dinosaurs Haplocanthosaurus and Diplodocus. In 1903, with T. W. Stanton of the United States Geological Survey, Hatcher explored the Judith River beds and together they settled the vexatious problem of their age, the published results appearing in 1905, after Hatcher’s death. His last piece of research, begun in 1902 and continued until his death in 1904, was an elaborate monograph on the Ceratopsia, one of the many projected by Marsh. Of this memoir Hatcher had completed some 150 printed quarto pages, giving a rare insight into the anatomy of these strange forms. The final chapters, however, which were based very largely upon Hatcher’s own opinions, had to be prepared by another hand.

Despite his early death, therefore, Hatcher rendered a very signal service to American paleontology—in exploration, stratigraphy, morphology, and systematic revision—and his activity in planning new fields of research, such, for instance, as the exploration of the Antarctic continent, gave promise of further high attainment, when his hand was arrested by death.

Summary.

It is not surprising that American vertebrate paleontology has arisen to so high a plane, when one considers the material at its disposal. Having a vast and virgin field for exploration, a sufficient number of collectors, some of whom have devoted much of their lives to the work, and a refinement of technique that permitted the preservation of the fragmental and ill conserved as well as the finer specimens, the results could hardly have been otherwise. Thus it has been possible to secure material almost unique throughout the world for extent, for completeness, and for variety. To this must be added a certain American daring in the matter of the restoration of missing portions, both of the individual bones and of the skeleton as a whole, such as European conservatism will not as a rule permit. This work has for the most part been done after the most painstaking comparison and research and is highly justified in the accuracy of the results, which render the fabric of the skeleton much more intelligible, both to the scientist and to the layman. Material once secured and prepared is then mounted, and here again American ingenuity has accomplished some remarkable results. Some of the specimens thus mounted are so small and delicate as to require holding devices comparable to those for the display of jewels; yet others—huge dinosaurs the bones of which are enormously heavy, but so brittle that they will not bear even the weight of a process unsupported—require a carefully designed and skilfully worked out series of supports of steel or iron which must be perfectly secure and at the same time as inconspicuous as possible. And of late the lifelike pose of the individual skeleton has been augmented by the preparation of groups of several animals which collectively exhibit sex, size, or other individual variations and the full mechanics of the skeleton under the varying poses assumed by the creature during life.

The work of further restoration has been rendered possible through comparative anatomical study, enabling us to essay restorations in entirety by means of models and drawings, clothing the bones with sinews and with flesh and the flesh with skin and hair, if such the creature bore; while the laws of faunal coloration have permitted the coloring of the restoration in a way which if not the actual hue of life is a very reasonable possibility.

Thus the American paleontologists have blazed a trail which has been followed to good effect by certain of their Old World colleagues.

With such means and methods and such material available, it is again not surprising that American paleontology has furnished more and more of the evidences of evolution, and disclosed to the eyes of scientists animal relationships which were undreamed of by the systematist whose research dealt only with the existing. It has also explained some vexatious problems of animal distribution and of extinction, and has connected up cause and effect in the great evolutionary movements which are recorded.

The results of systematic research have added hosts of new genera and species and of families, but of orders there are relatively few. Nevertheless a number, especially among reptiles and mammals, have come to light as the fruits of American discovery. But aside from the dry cataloguing of such groups, the American systematists have worked out some very remarkable phylogenies and have thus clarified our vision of animal relationships in a way which the recent zoologist could never have done. In this connection, the Permian vertebrates, which have been collected and studied with amazing success, principally by Williston and Case, should be mentioned, although the work is yet incomplete. Some of these forms are amphibian, others reptilian, yet others of such character as to link the two classes as transitional forms. Of the Mesozoic reptiles, a very remarkable assemblage has come to light, in a degree of perfection unknown elsewhere. These are dinosaurs, of which several phyla are now known; carnivores both great and small, some of the latter being actually toothless; Sauropoda, whose perfection and dimensions are incomparable except for those found in East Africa; and predentates, armored, unarmored, and horned, the last exclusively American. The unarmored trachodonts are now known in their entirety, for not only has our West produced articulated skeletons but mummified carcasses whose skin and other portions of their soft anatomy are represented, and which are thus far without a parallel elsewhere in the world. Other reptilian groups are well known, notably the Triassic ichthyosaurs, and the mosasaurs and plesiosaurs of the Kansas chalk. The last formation has also produced toothed birds, Hesperornis and Ichthyornis, which again are absolutely unique.

But it is in the mammalian class that the phylogenies become so highly complete and of such great importance as evolutionary evidences, for nowhere else than in our own West have such series been found as the Dinocerata and creodonts among archaic forms, the primitive primates from the Eocene, the carnivores such as the dogs and cats and mustellids, but especially the hoofed orders such as the horses. Of these hoofed orders, the classic American series of horses is complete, that of the camels probably no less so, while much is known of the deer and oreodonts, the last showing several parallel phyla, and of the proboscideans, which while having their pristine home in the Old World nevertheless soon sought the new where their remains are found from the Miocene until their final and apparently very recent extinction. These creatures show increase of bulk, perfection of feet and teeth, development of various weapons, horns and antlers, which may be studied in their relationship with the other organs to make the evolving whole, or their evolution may be traced as individual structures which have their rise, culmination, and sometimes their senile atrophy in a way comparable to that of the representatives of the order as a whole. Thus, for example, Osborn has traced the evolution of the molar teeth, and Cope of the feet, while Marsh has shown that brain development runs a similar course and that its degree of perfection within a group is a potent factor for survival.