Charles D. Amsler

Research Description:

The research that my students and I conduct is centered in several areas but most involve chemical interactions between organisms or ways in which organisms perceive, respond to, or otherwise interact with their chemical environments. A particular area of recent interest has been the interactions of antarctic macroalgae and invertebrates with herbivores or predators and with fouling microorganisms such as diatoms and bacteria. We are also interested in analogous questions with temperate and tropical organisms.

My laboratory also studies algal ecophysiology, often beginning with quantitative studies of the biochemistry, physiology, or swimming behavior of single cells. These algal studies start with the cell and focus in large part on physiological and behavioral adaptations to the microenvironments of the biofilm and planktonic communities. A particular area of current interest is the influence of nutrient and other chemical gradients on the swimming and settlement behavior of algal spores. We have also worked on bacterial chemotactic signal transduction. The bacterial studies started with the cell and focused on the biochemical signal pathway they use to control their behavior and on the adaptive constraints on flagellar gene expression. A research tool common to both the algal and bacterial studies is computer-assisted motion analysis of swimming behavior.

I am also interested in the ecophysiology and population structure of antarctic macroalgae and microalgae. Other, previous work has included research on environmental factors governing algal seasonality and on the taxonomy of filamentous brown algae.

Representative Publications:

Iken, K., C.D. Amsler, S.P. Greer, & J.B. McClintock. 2001. Quantitative and qualitative studies of the swimming behaviour of Hincksia irregularis (Phaeophyceae) spores: ecological implications and parameters for quantitative swimming assays. Phycologia 40: 359-366. {Awarded the 2002 Tyge Christensen Prize for best macroalgal paper in Phycologia during 2000 and 2001.}

Greer, S.P. & C.D. Amsler. 2002. Light boundaries and the coupled effects of surface hydrophobicity and light on spore settlement in the brown alga Hincksia irregularis (Phaeophyceae). Journal of Phycology 38: 116-124. {Honorable Mention for the 2003 Luigi Provasoli Award for best paper in Journal of Phycology during 2002.}

Amsler, C.D., K. Iken, J.B. McClintock, M.O. Amsler, K.J. Peters, J.M. Hubbard, F.B. Furrow, & B.J. Baker. 2005. Comprehensive evaluation of the palatability and chemical defenses of subtidal macroalgae from the Antarctic Peninsula. Marine Ecology Progress Series 294: 141-159.

Greer, S.P., K. Iken, J.B. McClintock, & C.D. Amsler. 2006. Bioassay-guided fractionation of antifouling compounds using computer-assisted motion analysis of brown algal spore swimming. Biofouling 22: 125-132.