Other Seminars

The balance of trade in mycorrhizas: phosphorus, nitrogen, and light availability mediate mycorrhizal mutualism and parasitism

The Curriculum for the Environment and Ecology hosts the distinguished Jenner Lecture in Ecology this Thursday, February 10th at 4:00pm in Wilson 128. This semester's Jenner speaker is Nancy Collins Johnson, an associate professor at Northern Arizona University, and a pioneer in investigating the relationships between plants and arbuscular mycorrhizal fungi.

Abstract --- We discuss two types of partial differential equation models of fishery harvesting problems. We consider steady state spatial models and diffusive spatial-temporal models. We characterize the distribution of harvest effort which maximizes the harvest yield, and in the steady state case, also minimizes the cost of the effort. We show numerical results to illustrate various cases.

Contemporary evolution as an agent of ecological change

Traits determine how species interact and, in turn, how communities and ecosystems function. Ecological theories typically assume that traits are static on so-called ecological time scales. However, recent evidence for contemporary evolution raises the question of whether rapid trait changes can impact ecological dynamics. I examined the effects of contemporary evolution in fishes on ecological processes in two aquatic ecosystems - New England lakes and Trinidadian streams.

Dispersal, Environmental Niches, and Oceanic-Scale Beta-Diversity in Deep-Sea Bivalves

Elucidating processes responsible for the structure of ecological communities is one of the longest standing questions in ecology. To gain insight, studies have related the degree of turnover between pairs of communities (beta-diversity) to the spatial and/or environmental distances between them. Strong relationships between beta-diversity and spatial or environmental distance suggest important roles of dispersal limitation or environmental filtering, respectively.

Using Insect Systems to Study How Organisms Interact with Beneficial and Harmful Microbes

Microbial communities within animals greatly influence their hosts' ecology and evolution. These diverse microbial associates consist of commensals, pathogens and mutualists. In such systems, hosts would benefit substantially if they could selectively recognize and accept beneficial microbes while still being able to avoid or attenuate infection by microbial pathogens.