Assistant Professor
PhD, University of Chicago, 2003
Post-doctoral Research Associate, University of Illinois, 2003-2005

Program Affiliation: Evolution, Ecology and Behavior

Research Groups Affiliation: Ecology

Adjunct Assistant Professor, W.K. Kellogg Biological Station, Michigan State University

Phone: 812/855-6009
Fax: 812/855-6082
Email Spencer

Hall research page

I study interactions between species and their environment at population, community, and ecosystem levels. I use freshwater plankton to study these interactions. Plankton provide an ideal system because they interact strongly, are readily manipulated in the lab and field, reproduce quickly, and supply crucial functioning to freshwater ecosystems.

My research program hinges on: (1) development of mathematical models; (2) experimental tests of those in both the laboratory and the field; and (3) surveys of natural systems. Combined, these approaches help me rigorously test logical, relevant ideas.

Currently, I run two main research projects:

We are studying the influence of infectious disease on population dynamics and community interactions. Our work focuses on the determinants of spatial and temporal dynamics of bacterial and fungal epidemics in Daphnia. This work relies on combination of community ecology, physical limnology, and epidemiological modeling. Current projects consider:

1. interactions between hosts and their food resources, their parasites, and their predators
2. spatial variability of parasitism among and between lake systems
3. temperature, physiology, and turbulence as determinants of the timing of epidemics, and
4. parasitism as a driver of selection on hosts.

Collaborators: Carla Cáceres (U of Illinois), Alan Tessier (NSF), Meghan Duffy and Marianne Huebner (Michigan State), and Sally MacIntyre (U of California-Santa Barbara).

2. Food Web Stoichiometry:

We are developing and testing new theory focused around the intersection of ecological stoichiometry and food webs. The stoichiometric approach explores the consequences in mismatches in the elemental composition of grazers and plants. It also considers how supply of resources, especially nutrients and light, can set the stage for these mismatches.Most of our work examines the ability of stoichiometric models to explain:

1. dynamics of algae and zooplankton
2. changes of community composition of both grazers and producers
3. ecosystem-level response to supply of light and nutrients, and
4. response of plant stoichiometry to resource supply gradients.

Collaborators: Mathew Leibold (U of Texas-Austin), David Lytle (Oregon State), Val Smith (U of Kansas)

Disease ecology:

Hall, S.R., C.R. Becker, J.L. Simonis, M.A. Duffy, A.J. Tessier, and C.E. Cáceres. 2009. Friendly competition: evidence for a dilution effect among competitors in a planktonic host-parasite system. Ecology, in press

Hall, S.R., J.L. Simonis, R.M. Nisbet, A.J. Tessier, and C.E. Cáceres. 2009. Resource ecology of virulence in a planktonic host-parasite system: an explanation using dynamic energy budgets. American Naturalist, in press

Cáceres, C.E., C.J. Knight, and S.R. Hall. 2009. Predator spreaders: predation can enhance parasite success in a planktonic host-parasite system. Ecology, in press

Duffy, M.A., S.R. Hall, C.E. Cáceres, and A.R. Ives. 2009. Rapid evolution, seasonality, and the termination of epidemics. Ecology, in press

Hall, S.R., C.M. Knight, C.R. Becker, M.A. Duffy, A.J. Tessier, and C.E. Cáceres. 2009. Quality matters: food quality and the course of epidemics in a planktonic host-parasite system. Ecology Letters, in press

Duffy, M.A., and S.R. Hall. 2008. Selective predation and rapid evolution can jointly dampen effects of virulent parasites on Daphnia populations. American Naturalist 171:499-510

Hall, S.R., L. Sivars-Becker, C. Becker, M.A. Duffy, A.J. Tessier, and C.E. Cáceres. 2007. Eating yourself sick: transmission of disease as a function of foraging ecology. Ecology Letters 10:207-218

Food-web stoichiometry:

Hall, S.R., M.A. Leibold, D.A. Lytle, and V.H. Smith. 2007. Grazing and the stoichiometric light:nutrient hypothesis: revisiting bottom-up and top-down effects on producer stoichiometry. Ecology 88:1142–1152

Hall, S.R., M.A. Leibold, D.A. Lytle, and V.H. Smith. 2006. Inedible producers in food webs: controls on stoichiometric food quality and composition of grazers. American Naturalist 167:628-637.

Hall, S.R., V.H. Smith, D.A. Lytle, and M.A. Leibold. 2005. Constraints on primary producer N:P stoichiometry along N:P supply ratio gradients. Ecology 86:1894-1904.