Office Hours: By appointment

Research interests: 
Plant-macrofossil analysis, Quaternary environments of the Midwest and Rocky Mountains

Professional experience:

• Professor Emeritus, 2000-present
• Chairman, Department of Geology, University of Iowa, 1992-1995
• Professor of Biology, University of Iowa, 1992-present (Joint appointment)
• Professor of Botany, University of Iowa, 1988-1992 (Joint appointment)
• Professor of Geology, University of Iowa, 1982-present.
• Associate Professor of Geology, University of Iowa, 1975-1981.
• Assistant Professor of Geology, University of Iowa, 1970-74.
• Geologist (intermittent), U.S.G.S., 1980-1985.
• Geologist (intermittent, temporary), U.S.G.S., 1972-79.
• Project Associate in Meteorology, University of Wisconsin, 1969-70.
• Teaching Associate, Geology Dept. University of Colorado, 1967-69.

Professional affiliations:

• Geological Society of America (Fellow)
• American Quaternary Association (Councilor, 2000-2004)
• Editorial Board, Plant Ecology, 2001
• Geological Society of Iowa
• Iowa Academy of Science (Fellow)