Helsinki group

The Helsinki group has been at the Department of Agricultural Sciences since 2011.
Nerea Abrego - Post Doc

I am broadly interested in community ecology, especially in linking general theory in community ecology to empirical research. In my PhD project I studied how human-induced environmental changes affect wood-inhabiting fungal diversity and assembly processes at different spatial scales, and how these processes are related to functional traits and interaction networks. During my postdoc at the Centre of Biodiversity Dynamics in the Norwegian University of Science and Technology, I expanded my core research by taking part into the development of statistical methods, in particular joint species distribution models, which enable community ecologists to more efficiently link theory to empirical data. Thanks to gaining expertise in joint species distribution modelling, I established collaborations with empirical researchers working on a broad range of taxonomical groups, such as birds, insects, mammals and plants.

Currently, I am an Academy postdoc establishing my own research group (Fungal Community Ecology Group) at the University of Helsinki. My current principal lines of research are:

1) How interspecific interactions change and determine community structure under environmentally stressful conditions, using root-associated fungi as a model system (personal post-doctoral fellow awarded by the Academy of Finland).

2) How interspecific interactions and stochastic processes influence the colonization success of wood-inhabiting fungi of conservation concern (PhD project funded by the University of Helsinki).

3) Global spatiotemporal patterns of the fungal diversity with special focus on fungi affecting human life.

4) Development of joint species distribution models for analyzing community data.

Recent publications by Nerea Abrego
Laura Antao - Post Doc

My main research interests are biodiversity, macroecology and global change. I am interested in biodiversity synthesis and biodiversity patterns, and how we can generalize information across taxa and habitats, and furthermore across scales. In my future research, I will examine patterns of biodiversity change using long-term data and large scale environmental drivers, such as climate and land-use.

Antoine Becker-Scarpitta - Post Doc

Profile: I am a plant ecologist focusing on community ecology, field botany, forest ecology. I started my studies in France in forest ecology, then in ecology and evolution in master’s degree. I obtained a PhD in Canada, QC, under the supervision of Mark Vellend at the University of Sherbrooke. The main question of my project was: What is the impact of environmental change on biodiversity? I built a set of hypotheses around two main questions: (i) What is the effect of environmental changes on forest vegetation? (ii) Which taxon, bryophytes or vascular plants, is most sensitive to global changes? To answer these questions, I use the framework of historical ecology and numerical ecology.

Research: I am currently postdoctoral researcher in the Spatial Food-Web Ecology Group. My main research interest is the temporal dynamic of the biodiversity in response to recent human-induced global changes. My current research program focuses on the long-term dynamics of the Arctic vegetation in response to warming, using modern frameworks of community ecology, functional ecology, and advanced statistical methods, e.g. joint species distribution models.

I am highly interested in theory in ecology, numerical tools, data visualization and natural history. For me, science is first and foremost a human story of collaboration and mutual aid, I enjoy sharing ideas, co-operated, help and discuss. I vote for an open science.

Alyssa Cirtwill - Post Doc

I am a network ecologist currently working as a postdoctoral researcher with Dr. Tomas Roslin. My main research interests are how we can describe the ways species fit into ecological networks and what the network perspective can add to our understanding of ecology. I am currently investigating how phenological change in plants and insects affects pollination networks, including crops that we humans depend on. I am also interested in how we can draw better conclusions from messy and missing data.


During my PhD work with Dr. Daniel Stouffer (University of Canterbury, New Zealand) I was introduced to network motifs, a way of describing meso-scale network structure and species’ roles in networks. I used motifs to explore differences in the ways that parasites and free-living species interact in food webs, and expanded motif theory to describe the roles of interactions as well as species. After my PhD I completed postdoctoral work with Dr. Anna Eklöf (Linköping University, Sweden) and Dr. Peter Hambäck (Stockholm University, Sweden). This work included linking species’ motif roles to traits such as body mass and habitat use, developing a simple Bayesian framework to supplement observed interaction data with prior knowledge, and applying this framework to networks based on spider gut contents.


Outside of research, I like to hike and make things. I spin, knit, and weave with wool, brew beer and mead, and love woodworking when I get the chance. I’m learning how to hunt for mushrooms and trying to find more time to read.

Helena Wirta - Post Doc

I am interested in ecological communities from various perspectives: what taxa they consist of, how are they structured, how they function and how did they evolve to their current day form as well as how they change. For my PhD, under supervision of professor Ilkka Hanski, University of Helsinki, I examined how the dung beetles in Madagascar had evolved, from where the species’ ancestors came to how speciation among closely-related species had taken place, and how ecological traits affected species’ roles. This species group and the study region, Madagascar, were ideal to examine species’ evolution, for the dung beetles are endemic and highly diverse. My main tool were molecular phylogenies, once we had collected dung beetles all over the island, resolving ecological traits of the beetles during the trappings.

After my PhD, I focused my research on the community composition and structure of a species poor Greenlandic community with professor Tomas Roslin, University of Helsinki. Here the paucity of species allowed encompassing nearly all the macroscopic species as examining how the species affect each other in the community. We created DNA barcodes for the vast majority of the animal and plant species, through wide collaborations with taxonomists. With the DNA barcodes we resolved who eats whom by identifying the consumers and consumed ones. We concentrated on arthropods, especially Lepidoptera and Diptera, and their predators, parasitoids as well as the plants they feed on. As the climate is warming up fast in the Arctic, our studies serve as baseline and the DNA barcodes as highly important tools for other research in the area.

My current research projects concentrate on honey bees. I have two research projects, an applied one examining how DNA based identification of organisms could improve the identification of floral and regional origin of honey, and another one using honey as a sample describing the environment and the trophic interactions of honey bees. Honey bee as a worldwide species offers a change to look at trends of how a species’ environment and trophic interactions change across different environments, and honey serves as a sample from which the organisms honey bees encounter can be identified by DNA. I also collaborate in various research projects, mainly on wild pollinators, and studying different aspects of pollination efficiency and changes in pollinator communities.

Recent publications by Helena Wirta
Tuomas Kankaanpää - PhD student

Profile: I'm currently working on my PhD, studying how food webs of herbivores and their parasitoid predators vary in relation to local climates and climate change in the High Arctic. By using molecular methods to reveal interactions between individual parasitoids and their hosts, I can construct quantitative food webs for a range of climatic conditions, both locally and on a larger circumpolar scale. In practice, my work involves arduous field work in Northeast Greenland, laborious high-throughput DNA-extraction and finally serious analysis of next-generation sequencing data. My interests in biology also cover evolutionary and developmental biology, which are, naturally, easy to integrate with any biological research.

Outside of research, I am an all-round nature nerd, enjoying especially birding, collecting and photographing insects, especially in wetlands and forests, often done with conservation in mind. I also like brewing beer, building bicycles and playing the banjo. I tweet about scientific stuff: @morphospaceman

Janne Koskinen - PhD student

Profile: I started in SFEG as a visiting PhD student in January 2016 as a visiting researcher from UEF. I am studying the food web and community structures of fungus-associated arthropods. Non-polypore fungi and their associated insects are an elementary part of woodlands around the globe, and also of great interest to many people – easily witnessed when visiting a market in autumn or opening a mushroom guide. Although highly diverse, the fungus-associated arthropod fauna is relatively poorly known, and provides a great opportunity to study and model food web functions and community composition in spatially and temporally discrete, ephemeral habitats. Thus, I aim to build an understanding of who eats whom, who lives where, and how these translate into mushroom damages affecting humans. I utilize metabarcoding to understand whom lives where – the cornerstone of all ecological knowledge.

Outside my research, I am also a mushroom fanatic, birder and all-round nature enthusiast often interested in the small or arcane. I am also interested in cooking, music, modern arts, taxonomy, history and particularly computer gaming and its effects on us. I tweet about science, various off-topic materials, natural history, and occasionally about Eurovision Song Contest as @jskoskinen

Bastien Parisy - PhD student


After completing my Masters in plant ecology and in modelling of ecological systems, I joined SFEG in September 2019 as a PhD student. My research is mainly focus on the interactions between plants and microbes as determinants of Arctic vegetation dynamics.


In a context of global changes, most of plant ecology frameworks have an aboveground bias that overlooked belowground importance. Consequently, our understanding of multiple relationships among abiotic soil parameters, interaction between soil microbiome and plants communities’ characteristics remains fragmented. I am interested by integrating a microbial perspective into recent conceptual frameworks of plant communities’ ecology. Indeed, I want to explore how soil communities’ dynamics shape the structure of plant communities in space and in time, but also how climatic and ecological processes affects each communities over the course of the plants’ life cycle and over generations of plants and microbes. My work involves fieldwork and experiments across Arctic (for a range of climatic conditions, both locally and on a larger circumpolar scale), high-throughput DNA-extraction, analysis of next-generation sequencing data, use of latest generation of statistical approaches and models.


Outside of research, I am a nature and hiking enthusiast. Amateur photographer, I like shooting landscapes, plants and various things during my trips. I also like playing ukulele, developing my knowledge about Anthropology, Astronomy and various types of arts such as music and cinema.

Sonja Saine - PhD student

My main research interests are community ecology and conservation biology. In specific, I am interested in how to apply community ecological theory in species conservation. In the beginning of 2020, I joined SFEG and Fungal Community Ecology group as a PhD student with Nerea Abrego (HY) and Reijo Penttilä (Luke) as my supervisors.

In my PhD, I am studying how different assembly processes affect colonization and community dynamics of wood-inhabiting fungi. My focus is especially on the role of interspecific interactions and stochasticity; how resident community influences the colonization success of a newly arriving species, and how predictable is the colonization success under identical abiotic and biotic conditions? I address these questions by reintroducing threatened wood-inhabiting fungi via inoculation, and reveal the following changes in mycelial communities by applying molecular methods and joint species distribution modelling. In addition, I will assess whether reintroductions could provide a novel tool for wood-inhabiting fungal conservation.

Outside of research, I am a big fan of music, nature, street dancing, cinema and ice cream.

Mikko Mäkelä - Undergraduate student

Profile: I started my studies at the Faculty of Biological and Environmental Sciences in 2013 with a major in Ecology and Evolutionary Biology. I have a background in Information studies at the University of Tampere. In the field of biology, I am especially interested in insect communities and the effects of climate change on their functioning and structure. I have been working on my bachelor and master's theses under the supervision of Tomas Roslin since October 2015. In my work, I will investigate the effects of certain environmental factors on arthropod community structure in the Zackenberg area of North-East Greenland. The High Arctic has experienced a drastic increase in temperature during the past few decades and the phenology of several taxa has changed. In my research, I utilize the concept of time-for-space –substitution for interpreting the effects of climate change on arthropod communities. I intend to compare the temporal variation observed in insect community structure to the variation in spatial, altitudinal scale.

In my spare time, I try to spend as much time as possible with my wife and son. I also enjoy reading books from a variety of fields.


Mikko Tiusanen (PhD student)

Isabella Palorinne (Project secretary)

Tea Huotari (Post Doc)