Research

Currently, my projects combine an ecological, modelling, genomic and chemical approach and deal with: i) insect community ecology, ii) plant defence to multi herbivory, iii) plant growth-defence strategies, iv) parasitoid behaviour, v) hyperparasitoid ecology and have an interest in the ecology of poison frogs.

Insect community ecology. Individual plants harbour species rich communities of insects. These communities are structured by trophic interactions of who eats whom, but are also riddled with indirect interactions. One type of these interactions is mediated by the plant. In response to attack by one herbivore the plant changes its phenotype. Each community member may respond differently to this new phenotype and thus induced responses to one herbivore may alter community composition on the individual plant. I study how predictable these indirect interactions are for insect community structure and assess the importance of these processes in the evolution of (induced) plant defence.

Plant defence to multi herbivory. When attacked by multiple herbivores, plants should be able to play a defence strategy that is the best solution to attack by this community rather than maximizing its defence to each individual attacker. This is because a defence response to one herbivore may make plants more susceptible to colonisation by other herbivores. Moreover, the physiological response to one herbivore may affect the capabilities of a plant to respond to the next herbivore. I study how plants deal with multi herbivore attack, what are their physiological limitations in response to multi attack and whether plant species differ in their solutions to defend themselves against their specific dynamic herbivore community.

Plant growth defence strategies. While defending against herbivores, plants also interact with neighbouring plants. These neighbours compete for light and nutrients, but may also affect the likelihood of herbivore attack on a focal plant. Induced defence responses to herbivores also affects growth parameters and plant physiological machinery for defence and response to light interact. How dynamic processes of plant-plant-herbivore interactions and in particular the role of induced plant responses is played out on a spatial scale is still poorly understood. I study how dynamics of plant-plant-herbivore interactions shapes plant growth-defence strategies.

Host location by parasitic wasps. Parasitic wasps that lay their eggs in or on the bodies of other insects such as aphids or caterpillars and use these insects as a host for development of their offspring, are well known to use plant odours in location of their hosts. When these aphids or caterpillars feed from the plant, they induce changes in plant odours that the parasitic wasps use as a reliable cue of where their hosts are located. However, when the plant or plant stand is under attack by multiple herbivores and these interactions take place in complex habitats, host location by parasitic wasps is less straight forward. I study how habitat complexity, such as presence of multiple herbivores, affects efficiency of host location and which strategies parasitic wasps evolved to cope with complex environments.

Hyperparasitoid ecology: The enemy of your enemy`s enemy. Parasitic wasps in turn are attacked by other parasitic wasps. These hyperparasitoids lay their eggs inside the larvae of parasitic wasps when those are still inside their herbivore host or lay eggs in/on pupae of parasitic wasps when they left the herbivore to spin their silk cocoon. Since their hosts are not only hidden in a plant community but also are frequently inside a herbivore, they may be very difficult to find. I study how hyperparasitoids locate the parasitic wasps and how the interaction network of the plant, herbivore, parasitic wasp and hyperparasitoid is structured and functions.

Ecology of poison frogs. During my masters I was trained as a vertebrate ecologist with particular interest in the ecology of Neotropical poison frogs (Dendrobatoidae). Apart from their bright colours that advertise toxicity, the frogs have a wide range of reproductive strategies in which one or both parents provide elaborate care to their offspring. I studied plasticity in parental care of these colourful frogs in French Guyana and Ecuador.