Dr. Tod Osier

Research in Ecology

My research interests focus on the ecology of plant-insect interactions. Specifically, I am interested in how plant chemistry affects the distribution and abundance of herbivorous insects on plants, especially in relation to plant defense theory. Plants and the insects that feed upon them constitute greater than half of the species diversity of macroscopic organisms on the planet; every green plant has insect herbivores that chew its tissues or suck its juices. Due to their abundance and ubiquity, insect herbivores are often our most important competitors for agricultural and forest products, and plant-feeding by insects is a major conduit of energy from primary producers to higher trophic levels. Because plants are continuously under attack from herbivores, they have evolved a dazzling array of chemical and physical defenses for protection. Factors that alter plant defense and subsequently mediate plant-insect interactions are of particular interest to me. These factors operate in both ecological and evolutionary time; the net result is a mosaic of defensive expression with which insects must contend. My interest is to identify those factors that are important for herbivores and to determine their generality within and among systems.

Courses Taught:

• BI 76 Environmental Science
• BI 172 General Biology III - Ecology, Evolution, and Environmental Science
• BI 260 Ecology
• BI 366 Ornithology
• BI 395 & 396 Independent Research I & II
• BI 397 & 398 Internships

Recent Publications:

Lindroth RL, Osier TL, Barnhill HRH, Wood SA (2002) Effects of genotype and nutrient availability on phytochemistry of trembling aspen (Populus tremuloides Michx.) during leaf senescence. Biochem Syst Ecol 30:297-307

Kopper BJ, Jakobi VN, Osier TL, Lindroth RL (2002) Effects of paper birch condensed tannin on whitemarked tussock moth (Lepidoptera: Lymantriidae) performance. Environ Entomol 31:10-15

Osier TL, Lindroth RL (2001) Effects of genotype, nutrient availability, and defoliation on aspen phytochemistry and insect performance. J Chem Ecol 27:1289-313

Osier TL, Hwang S-Y, Lindroth RL (2000) Within- and between-year variation in early season phytochemistry of quaking aspen ( Populus tremuloides Michx.) clones. Biochem Syst Ecol 28:197-208

Osier TL, Hwang SY, Lindroth RL (2000) Effects of phytochemical variation in quaking aspen Populus tremuloides clones on gypsy moth Lymantria dispar performance in the field and laboratory. Ecol Entomol 25:197-207