Trying to summarize my research with a few key words, ecological networks, specialization and insect diversity might do. My research interests are based on my fascination for nature and biodiversity. I am puzzled by how many different species (especially insects) can be found on our planet and how many stories can be told when you look at them closely. In my view, fundamental research that keeps in mind the current environmental challenges is the way we can move towards a better understanding of nature, which will prove useful for a sustainable future (but has also merits in its on right).
I try my best to integrate observation, experimentation and theory to achieve this, mostly asking questions about species communities, interspecific interactions and environmental change. One theme is to identify mechanistic predictors of dynamics and variation in biotic niches and interaction patterns on different scales. I search for ecological conclusions that give sense in light of both theory and natural history, and that are unlikely to be caused by sampling artifacts. Much of my work so far deals with plant-pollinator interactions in a community context, but I am also studying other mutualistic (seed dispersal) and antagonistic (plant-herbivore, host-parasitoid, predation) interactions. Apart from bees and plants, I have worked about ants, dragonflies and damselflies, birds, neotropical bats, aphids, caterpillars and their parasitoids, and purely theoretical beasts.
Daily and seasonal dynamics of ecological interaction networks: temporal structure and its functional consequences
(funded by DFG)
PhD student Benjamin Schwarz and I are focusing on the temporal dimension of network ecology. We are developing concepts, theory and analytical techniques for understanding the dynamics and functional consequences of temporal structure in species interaction networks on multiple timescales (within a day, within a year and among years). We start from the idea that many different types of networks are actually built from consumer-resources processes. Besides a general approach, a special focus is on diel dynamics of plant-pollinator interactions.
On this topic, I am also collaborating with Diego Vázquez, Carsten Dormann, Gita Benadi, Chris Kaiser-Bunbury.
Tree species diversity effects and the importance of relative timing and species origin for insect-mediated interactions between neighbor plants
(funded by Baden-Württemberg-Stiftung, Eliteprogramm for Postdocs)
As a collaboration within the IDENT network, we are developing tree-herbivore-enemy networks for a set of tree diversity experiments in Europe and North America. We will use the temporal networks approach to help explain variation in tree diversity effects on herbivory and understand how exotic trees are integrated into native tree-herbivore networks.
Supervised thesis students study different aspects of herbivorous insects and their antagonists across tree species. Main collaborators are Michael Scherer-Lorenzen, Charles Nock, Laura Rose and Dominique Gravel.
I am currently looking for a PhD candidate to work on this project.
Plant diversity and host-parasitoid food webs based on trap-nesting Hymenoptera
(funded by DFG / Jena Experiment)
As part of the synthesis phase of the Jena Experiment, I have organized a workshop together with Alexandra Klein. In this workshop and its aftermath, we have compiled a big dataset of multiple studies using trapnests to study bees, wasps and their natural enemies. We use these data, collected with a standard method, to understand how food webs change with changing plant diversity in a range of experimental and natural settings.
Spruce budworm and quantitative host-parasitoid food webs over time
(originally funded by DFG / Forschungsstipendium)
Together with Kevin McCann (U of Guelph) and Eldon Eveleigh (NRCan, Canadian Forest Service, Fredericton), I am looking at the balsam fir food web. In this system, Spruce Budworm (Choristoneura fumiferana) is notorious for devastating outbreaks after long periods of low density. We are interested in the host-parasitoid food web surrounding this core interaction and are developing quantified food webs to understand their temporal dynamics.
Other projects (pollinators, mutualistic networks and more)
I am involved in a couple more collaborative projects, modeling and synthesis studies. Topics include plant-pollinator interactions, plant-frugivore interactions, host-parasitoid interactions, … — from very applied to very fundamental, all within my broad range of research interests. Come back for updates.