Published by Joseph Leidy, this is the first illustration in print of Hadrosaurus bones, from Cretaceous Reptiles of the United States, 1865. Series: Smithsonian Contributions to Knowledge, volume 14, number 192.
AN OVERVIEW OF THE GEOSCIENCES
The interdisciplinary study of planet Earth involves at present a multitude of interacting and overlapping disciplines with historical roots in the traditional investigations conducted for more than two centuries under the headings of Geology and Paleontology.
Geology studies the physical, chemical and mineralogical structures of the planet and their various transformations since the Earth’s formation within the solar system some 4.5 billion years ago. Stratigraphic mapping is prominent among the various methodologies employed by this discipline since its early beginnings. It involves the surveying and recording of the physical disposition of layers of rocks as evidence of historical transformations and upheavals.
Paleontology is concerned with the origin, evolution and distribution of life forms, from organisms to ecosystems, in relation to the inanimate physical structures in which they are embedded. From Paleontology’s earliest stages a prominent methodology has focused on the study of fossil remains of organisms, as evidence of life’s evolutionary changes and as clues for identifying strata.
HISTORICAL OVERVIEW: From ancient lore to plate tectonics
Geology and Paleontology rose as independent scientific disciplines, in the modern sense of those terms, during the eighteenth century. They inherited a vast amount of empirical knowledge about rocks and land formations that had been accumulated through millennia of observation and analysis of phenomena. This loosely organized knowledge had often been acquired in the pursuit of practical ends, such as activities based in the use of rocks for construction of dwellings and monuments and for the fashioning of artifacts. Another important source of information originated in sophisticated systems of practices that were deployed in the extraction of mineral ores for the smelting of metals and in the search for mineral veins in rock fractures. Greek thinkers were aware of the spheroidal shape of the Earth and in Hellenistic times Eratosthenes measured its radius with remarkable accuracy.
The Scientific Revolution of the seventeenth century rose with the mathematical and experimental treatment of mechanical and astronomical phenomena by means of methods based in the framing of hypotheses and their empirical testing by means of instruments. The application of these methods rapidly extended to other fields of research in the study of nature, including those aimed at revealing the structure and history of the Earth and the life forms dwelling in its upper layers.
In the eighteen-century the new scientific approach to the acquisition and organization of knowledge became integrated into geological and paleontological studies through the work of several practitioners, such as John Strachey (1671 – 1743), Johann Lehmann (1719-1767), James Hutton (1726-1797), Peter Pallas (1741-1811), Abraham Werner (1749-1817), and various others.
Hutton is widely considered the father of scientific geology. He was part of the extraordinary intellectual flowering known as the Edinburgh Enlightenment, which included such outstanding luminaries as Adam Smith, David Hume, Joseph Black, and James Watt. His extensive investigations of rock outcrops in Scotland and Northern England led him to conceive revolutionary ideas that he summarized in his seminal paper, “Theory of the Earth” [Transactions of the Royal Society of Edinburgh, vol. 1, Part II, pp. 209-304, plates I and II, published 1788]; the link to this journal in the LHL catalog is given below.. He submitted it in 1785 to the Royal Society of Edinburgh, which historians consider to be the most active scientific institution in the world at that time. Hutton realized that igneous rocks, formed from molten materials, were different and younger than the sedimentary rocks into which they penetrated. He was led to a theory, later known as “Uniformitarianism, ” which stated that the same processes and laws that explain the formations observed in the Earth have also operated in distant earlier times and continue operating at present. (For books by or about James Hutton, please see p. 2 of this research guide, "Geological Time.")