- Professor of Biology, Mount Vernon Nazarene University, 2000 to present
- Associate Professor of Biology, Mount Vernon Nazarene University, 1994-2000
- Professor, Division of Science and Mathematics, Oklahoma Wesleyan University, 1982-1994
- Columbus Astronomical Society
- Kokosing Chapter of Ohio Archaeological Society
- Mid-American Paleontological Society
- Ohio Fish and Wildlife Management Association
- Ohio Chapter of the Wildlife Society
- Ohio Chapter of the American Fisheries Society
Published Works & Presentations:
- "Crinoid Assemblage from the Barnsdall Formation, Late Pennsylvanian (Missourian) Washington County, Oklahoma," (with Pabian, Lewis and Holterhoff). Geological Society of America, 1995; Oklahoma Geology Notes, August 1995.
- "Taphonomy of a crinoid lagerstatte deposit, Barnsdall Formation (Upper Pennsylvanian), northeastern Oklahoma," (with Lewis, Holterhoff and Pabian). Geological Society of America, National Meeting, 1998.
- "Prey-predator, Parasite, and Commensal Relationships with Late Pennsylvanian Crinoids and Associated Fauna from the Barnsdall Formation (Late Pennsylvanian, Missourian/Virginian) of Northeastern Oklahoma." Spring Meeting of the Nebraska Academy of Sciences, 1997.
- "An Immature Brachymetopid Trilobite From the Iola Formation (Late Pennsylvanian - Missourian) Near Sand Springs, Tulsa County, Oklahoma, Nebraska Academy of Science, 1994.
- Lewis, R.D., P.F. Holterhoff, D. Mosher, and R.K. Pabian. 1999. Taphonomy of a crinoid lagerstatte deposit, Barnsdall Formation (Upper Pennsylvanian), northeastern Oklahoma. Geological Society of America 1998 Abstracts with Programs v.30, no.7, p. A-31. Reprinted in Oklahoma Geology Notes v. 59, no. 4, p. 160, August 1999 issue.
Awards and Recognition:
- Recipient of Mount Vernon Nazarene University 2002-2003 Presidents Award For Excellence in Teaching.
- Recipient of Excellence in Education Award, and featured in December 2003 issue of Ohio Magazine as one of Ohios top 100 educators.
- Ohio Environmental Education Grant, 1997
- OEEF Grant "The Clear Fork River Project - An Environmental Education Project," 1997, was named as one of twelve statewide examples of outstanding environmental education.