Growth of a Prehistoric Time Scale

This readable history recounts the development of the prehistoric time scale, which is based primarily upon the fossil record. The author begins with early accounts of scientific inquiry in ancient Greece and follows the quest for principles that led to the formation of an interpretive time scale. Although the basic units of this scale were established before Darwin, it is now known that organic evolution through natural selection is reflected in the stratigraphic sequence of fossils, and thus in the time scale itself. The author discusses recent modifications in the use of the shorter units and points out some challenging new avenues of research that have been opened up by using such units to reconstruct earth history. Stress is placed on the role that biological principles, particularly evolution, have had in the establishment and use of units in the time scale. Because this book covers the development of the time scale in a more detailed way than it possible in general textbooks, and because it emphasizes the role evolution has in reckoning past time, it will be useful supplementary text for courses in introductory geology, evolution, paleontology, stratigraphy, and the philosophy and history of science. It will also enlighten the general reader who is curious about the scale of time units geologists use.