1990 "Systematic significance of lactate dehydrogenase variation at the generic level in percids," presented to the 70th meeting of the American Society of Ichthyologists and Herpetologists, Charleston, South Carolina, 19 June

1990 "Osteology of darters," presented to the 70th meeting of the American Society of Ichthyologists and Herpetologists, Charleston, South Carolina, 19 June (Poster)

1992 "Changes in the aquatic biodiversity of Illinois during the past 110 years," presented to the Illinois Natural History Survey, Champaign, 17 November.

1993 "What's all the fuss about biodiversity?" presented at Chicago Botanic Garden Symposium, "Environmental challenges in northeastern Illinois," 27 March.

1993 "Natural divisions of Illinois as applied to aquatic ecosystems," presented at the Illinois EPA Bioassessment Workshop, Springfield, IL, 29 April.

1993 "Introduction to minnow taxonomy," workshop given at USEPA sponsored Midwest Environmental Indicators and Biocriteria Conference, Chicago, 7 May.

1993 "Are there as many species of darters as minnows in North America?" presented to 73rd annual meeting of the American Society of Ichthyologists and Herpetologists, Austin, Texas, 28 May.

1993 "Reproductive behaviors of percid fishes," presented to national meeting of the North American Native Fishes Association, Urbana, 12 June.

1994 "Identifying and protecting Illinois' most biologically significant streams," presented to annual meeting of Illinois Chapter of American Fisheries Society, Marion, 9 March.

1994 "The state of darter systematics," presented at the 74th annual meeting of Ichthyologists and Herpetologists, Los Angeles, California, 7 June.

1994 "Determining the future of ecological diversity in Illinois: Aquatic community diversity," presented at symposium organized by Green Strategies, Wesleyan University, Bloomington, Illinois, 18 June.

1996 "Egg mimicry as an adaptive strategy in darters," presented to the Department of Zoology, University of Texas, Austin, 23 May.

1996 "Egg mimicry as an adaptive strategy in darters," presented to the Department of Biology, Murray State University, Murray, Kentucky, 24 October.

1996 "Egg mimicry as an adaptive strategy in darters," presented to the Department of Biology, Wright State University, Dayton, Ohio, 13 November.

1996 "Egg mimicry as an adaptive strategy in darters," presented to the Department of Biology, Miami University, Oxford, Ohio, 14 November.

1998 "Egg mimicry as an adaptive strategy in darters," presented to the Department of Zoology Graduate Student Association, Southern Illinois University, Carbondale, 2 March.

1999 Competitive disjunction: a new model of allopatric speciation," presented to the Darter Study Group, Russel Springs, Kentucky, 3 April.

1999 Competitive disjunction: a new model of allopatric speciation," presented at annual meeting of American Society of Ichthyologists and Herpetologists, Pennsylvania State University, State College, 25 June.

1999 Phylogenetic relationships among fantail darters (Percidae: Etheostoma: Catonotus)," co-authoredwith Jean Porterfield for annual meeting of American Society of Ichthyologists and Herpetologists, Pennsylvania State University, State College, 25 June.