LESSONS LEARNED: BOB DOTT AND THE ETHICS OF DEEP TIME

Bob Dott’s textbook, “Evolution of the Earth”, with Roger Batten and later Donald Prothero, was unique in teaching “how do we know,” rather than simply “what do we know,” about Earth history. It was more than a recitation of the events of Earth history and the approach was explicitly stated in the preface of the book. Bob fulfilled it in lectures and labs. The first edition was published in 1971, five years after I got my BS degree from Madison but, fortunately Bob had us work on and cross reference the facies, geologic, and paleo geographic maps, cross sections, and various other charts and diagrams such as unconformity bounded sequences that were prototypes for what were to appear in his text. We learned how to find paleo shorelines, boundaries of cratons and mobile belts, ancient land masses and epi continental seas; how to determine sea level changes and prevailing directions of current flow, climatic zonation, mountain building episodes, correlation of sediments by their fossil content; and how to assess the fitness of the environment in which prehistoric organisms lived as well as their effects upon it—in short, how to define ancient worlds back into the distant past. We unraveled Earth history with Bob’s guidance from the very beginning of our education! But Bob also taught us humility, encouraging us to apply TC Chamberlin’s, “Method of Working Hypotheses,” in our interpretations. Understanding our fallibility helped us find a kinship with the founders of geology.

A few years ago, Bob told me that Aldo Leopold was one of his heroes. In his “Sand County Almanac,” Leopold repeatedly cited the lessons of deep time to express dismay about the “commodification of nature.” The “ethics of deep time” run quietly throughout Bob’s text. That the past was different from the present, yet natural laws operative in deep time are consequential today, should sober everyone’s conception of their place on Earth. Humans propose, but nature disposes. It is a difficult lesson to learn. Judging by the waning presence of historical geology classes in the curricula of geoscience departments, and the ongoing commodification of nature, Bob Dott’s lessons about the ethics of deep time are needed more than ever.