Current research


The topic of my PhD studies is 'Ecology and evolution of parasitoid communities in leaf-mining and gall inducing sawflies'.

Host and parasites typically form complex food webs spanning multiple trophic levels, and it has been proved that natural enemies of herbivores can also affect their host-plant use. I will use parasitoids of gall-inducing sawflies (Euura and Pontania) and leaf miners (the tribe Fenusini and the Heterarthrinae) to investigate the ecology and evolution of parasitoid communities. Parasitoids are insects that lay their eggs in or on the bodies of other insects, eventually killing the host.

Parasitoids are important mortality factor for sawflies, and they could be important driving force behind the diversification of gall morphologies. Diversifying effects can operate either “top-down” or “bottom-up”. It has been proposed that diversification of plants leads to diversification of herbivores which, in turn, leads to increased diversity in parasitoid species. It is still unknown if this could happen in parasitoids, but there is some evidence that colonization of rapidly diversifying plant groups facilitates specification in plant-feeding insects. There has been little research on tritrophic plant-herbivore-parasitoid interactions, and the purpose of my study is to discover this tritrophic interaction between plants, sawflies and parasitoids. 


I am concentrating in coevolutionary issues, and my main questions are:

  • How are complex tritrophic food webs assembled?
  • How do coevolutionary interactions between parasitoids and their host species vary in time and space?
  • Do vertical diversification effects occur in complex food webs?




Tommi Nyman Academy Research Fellow (University of Joensuu)

Heikki Roininen Professor of animal ecology (University of Joensuu)



Academy of Finland