Outi Vesakoski

Principal Investigator

Department of Finnish language and Finno-Ugric linguistics, University of Turku. (Earlier at the Department of Biology, UTU)

My research revolves around the study of language change over time and space, employing an evolutionary approach. I lead a team that applies research methods derived from population biology, phylogenetics, landscape ecology, geography, and computational sciences to analyze language data. My (not so) secret final aim is to contribute to the study of the human linguistic past and use that aside from other disciplines studying the human past. Historical linguistics has so much to offer for studies of human diversity!


Linguistic variation exhibits a fascinating spatial dimension that intrigues me.I am driven to unravel the patterns and underlying factors shaping the current linguistic landscape. How did the Finnish language spread over the landscape, that was Saami speaking since before the Iron Age? How did the Finnish dialects evolve? How did the Finnish genetic landscape evolve – and did the formation of genetic diversity have to do with the formation of linguistic diversity? Could the formation of genetic diversity be linked to the emergence of linguistic diversity, as suggested by Hunley (2015) and the differential permeability of group boundaries for people and languages?

And what is the history of the Uralic language family? The basic questions are still under debate – where was the geographical origin of Proto-Uralic, how did it spread across different regions and what is the age of the language family? To shed light on these mysteries, I employ innovative datasets such as UraLex (lexical cognate data) and UraTyp (linguistic typological data).

Significantly, our research team has developed a cutting-edge computational framework that seamlessly transforms the information attained in historical linguistics into easily accessible databases. Moreover, we have devised metrics that facilitate cross-comparisons between linguistic history, genetic history, and archaeological records.


The title of my PhD thesis was “Local and sexual divergence in host-use traits and anti-predator adaptations in the marine herbivore Idotea balthica”. The study dealt with local adaptation and ecological speciation; I studied population divergence in phenotypical traits. This work was supervised by doctors Veijo Jormalainen, Sami Merilaita and Tuija Ramsay.

In addition to my linguistic research, I still work with the intriguing realm of evolutionary biology. This side of my work includes the evolution of personality in marine isopods Idotea balthica. My investigations center around understanding sexual differences in personality within this species. To accomplish this, I conduct studies on the same marine crustacean herbivore, Idotea balthica (Pallas), that I previously examined in my doctoral thesis. This research is conducted in collaboration with Maria Yli-Renko, Dr. Jenni Pettay, and Dr. Eva Rothäusler.

In co-operation with Tiia Forsström and Dr. Amy Fowler we initiated studies on the ecology of marine invasive species with focus on the American white fingered mud crab (Rhitropanopeus harrissii). The thesis was defended 2017 and was supervised by Prof. Veijo Jormalainen and Academy Researcher Anti Vasemägi.

Finally, to my great pleasure, my hobby expanded to a master thesis project by Iida Nikkilä: She collected baseline information about phenotypic variation in the growth factors and morphology of the Archipelago Sheep. The goal is to maintain genetic diversity in this breed while breeding it towards faster growth or better quality of the fur. Also this thesis was supervised jointly with Dr Jenni Pettay.

Happened so far

  • 2025 – please hire me
  • 2022-2024 Research fellow at the Turku Institute for Advanced Studies (TIAS); Dept of Finnish language and Finno-Ugric linguistics, UTU
  • 2020-2022 PI/Coordinator of interdisciplinary URKO project (sites.utu.fi/urko, Finnish Academy Funding for Dept of Biology (Päivi Onkamo), Dept of Finnish languages and Finno-Ugric linguistis (Sirkka Saarinen) and Geography and Geology (Harri Tolvanen), UTU
  • 2019 (Jan-June) University Lecturer of Environmental Sciences
  • 2018 Visiting researcher at the Department of Linguistics and Phylology at the Uppsala University, Sweden
  • 2014-2019 PI of the BEDLAN-initiative with Kone Foundation funding (SumuraSyyni and AikaSyyni) at the Department of Biology, University of Turku
  • 2013-2014 (Sep-Aug) EU adviser at MTT Agrifood research Finland (at Jokioinen)
  • 2011-2013 (Jan-July, 2,5 years) University lecturer in (aquatic) ecology at Department of Biology, University of Turku
  • Nov 2010→ Post doc at BEDLAN
  • 2010
    • a) Part time post doc at BEDLAN and
    • b) Part time planner at the South-West Finland Centre for Economic Development, Transport and the Environment (former LOS) as a marine biologist in the NANNUT project
  • 2009 Post roc research in a project financed by Kone Foundation: Herbivore adaptations to local selective environment: Variation in gut microbial activity, predator avoidance and behavior in Idotea balthica
  • 2009 PhD finally defended
  • 2007-2009 All together 9 mo at the South-West Finland Regional Environmental Centre (LOS); Preparing an EU-project called NANNUT to study the underwater biodiversity of the Baltic Sea and applying the data to environmental governance
  • 2003-2009 PhD studies at the University of Turku, Department of Biology, Section of Ecology
  • 2001 MSc about the effects of acidification to fluctuating asymmetry of perch (Perca fluviatilis). The degree included also studies of Finnish and Estonian language.

List of publications


  • Maurits, L., de Heer, M., Honkola, T., Dunn, M. & Vesakoski, O. 2020: Best practices in justifying calibrations for dating language families. Journal of Language Evolution 5 (1,), 17–38. https://doi.org/10.1093/jole/lzz009


  • Tambets, K., Yunusbayev, B., Hudjashov, G., Ilumäe, A-M., Rootsi, S., Honkola, T., Vesakoski, O., Atkinson, Q., Skoglund, P., Kushniarevich, A., Litvinov, S., Reidla, M., Metspalu, E., Saag, L., Rantanen, T., Karmin, M., Parik, J., Zhadanov, S.I., Gubina, M., Damba, L.L., Bermisheva, M., Reisberg, T., Dibirova, K., Evseeva, I., Nelis, M., Klovins, J., Metspalu, A., Esko, T., Balanovsky, O., Balanovska, E., Khusnutdinova, E., Osipova, L., Voevoda, M., Villems, R., Kivisild, T., Metspalu, M. (2018). Genes reveal traces of common recent demographic history for most of the Uralic-speaking populations. Genome Biology. 19:139.
  • Honkola, T., Ruokolainen, K., Syrjänen, K. J. J., Leino U, Tammi, I, Wahlberg, N. & Vesakoski, O. (2018). Evolution within a language: Environmental differences contribute to divergence of dialect groups. BMC Evolutionary Biology. 18:132.
  • Forsström, T., Vesakoski, O., Riipinen, K., Fowler, AE (2018). Post-invasions demography and persistence of a novel functional species in an estuarine system. Biological Invasions 20 (11): 3331–3345
  • Yli-Renko M., Pettay J.E., Vesakoski O. (2018). Sex and size matters: Selection on personality in natural prey-predator interactions. Behavioural Processes 148: 20-26.
  • Lehtonen T., Vesakoski O., Yli-Rosti J., Saarinen A., Lindström K. (2018). The impact of an invasive mud crab on brood success of nest-building fish in the Northern Baltic Sea. Biological Invasions 20(4): 981-993.


  • Riipinen K., Mikkola S., Ahola M.K., Aalto M.M., Olkinuora A., Vesakoski O. (2017). Habitat selection of the mud crab Rhithropanopeus harrisii in its newly invaded range. Aquatic Invasions 12: 191–200.


  • Syrjänen K., Honkola T., Lehtinen  J., Leino A., Vesakoski O.
    (2016). Applying population genetic approaches within languages: Finnish
    dialects as linguistic populations. Language Dynamics and Change 6:
  • Forsström T, Fowler A., Vesakoski O. (2016). The introduced dark false mussel, Mytilopsis leucophaeata (Conrad, 1831) has spread in the northern Baltic Sea. BioInvasions Records.


  • Forsström T,  Fowler A.,  Vesakoski O. (2015). An introduced species
    meets the local fauna: Predatory behaviour of the North American
    White-Fingered mud crab (Rhithropanopeus harrisii) in the Fucus vesiculosus dominated habitat of the Northern Baltic Sea. Biological Invasion 17: 2727-2741.
  • Yli-Renko M., Pettay J., Vesakoski O. (2015). Personality-dependent survival in the marine isopod Idotea balthica. Ethology 121: 135-143.


  • Lehtinen J., Honkola T., Korhonen K., Syrjänen K., Wahlberg N.,
    Vesakoski O. (2014). Behind family trees: Secondary connections in
    Uralic language networks. Language Dynamics and Change. 4: 189-221.
  • Mattila J.M., Zimmer M., Vesakoski O., Jormalainen V. (2014).
    Habitat-specific gut microbiota of the marine herbivore Idotea balthica
    (Isopoda). Journal of Experimental Marine Biology and Ecology 455: 22–2.

2013 and earlier

  • Vesakoski O. & Jormalainen V. (2013). Ignored patterns in
    studies of local adaptations: When the grass is greener on the
    allopatric site. Ideas in Ecology and Evolution 6: 32-36.
  • Syrjänen K., Honkola T., Korhonen K., Lehtinen J., Vesakoski O.,
    Wahlberg N. (2013). Shedding more light on language classification using
    basic vocabularies and phylogenetic methods: A case study of Uralic.
    Diachronica 30(3): 323-352.
  • Fowler A., Forsström T., von Numers M., Vesakoski O. (2013). The North American mud crab Rhithropanopeus harrisii (Gould 1841) in newly colonised Northern Baltic Sea: distribution and population demography. Aquatic Invasions 8: 89–96
  • Honkola T., Vesakoski O., Korhonen K., Lehtinen J., Syrjänen K.,
    Wahlberg N. (2013). Cultural and climatic changes shape the evolutionary
    history of the Uralic languages. Journal of Evolutionary Biology 26:
  • Vesakoski O., Rautanen J., Jormalainen V., Honkanen T. (2009).
    Divergence in host use ability of a marine herbivore from two habitat
    types. Journal of Evolutionary Biology 22: 1545-1555.
  • Vesakoski O., Boström C., Jormalainen V., Honkanen T. (2008). Sexual
    and local divergence in host exploitation in the marine herbivore Idotea baltica (Isopoda). Journal of Experimental Marine Biology and Ecology 367: 118-126.
  • Vesakoski O., Merilaita S., Jormalainen V. (2008). Reckless males,
    rational females: Dynamic trade-off between food and shelter in the
    marine isopod Idotea balthica. Behavioural Processes 79: 175-181.
  • Jormalainen V., Honkanen T., Vesakoski O. (2008). Geographical
    divergence in host use ability of a marine herbivore in alga-grazer
    interaction. Evolutionary Ecology 22: 545-559.
  • Korpinen S., Honkanen T., Vesakoski O., Hemmi A., Koivikko R.,
    Loponen J., Jormalainen V. (2007). Macroalgal communities face the
    challenge of changing biotic interactions – Review with focus on the
    Baltic Sea. Ambio 36: 203-211.
  • Jormalainen V., Honkanen T., Vesakoski O., Koivikko R. (2005). Polar extracts of the brown alga Fucus vesiculosus (L.) reduce assimilation efficiency but do not deter the herbivorous isopod Idotea baltica (Pallas). Journal of Experimental Marine Biology and Ecology 317: 143-157.
  • Jormalainen V., Honkanen T., Mäkinen A., Hemmi A., Vesakoski O.
    (2001). Why does herbivory sex matter? Sexual differences in utilization
    of Fucus vesiculosus by the isopod Idotea baltica. Oikos 93: 77-86.

Books and book chapters

  •  Vesakoski O. (2017). Uusia näkökulmia Suomen kielellisen alkuperän
    tutkimiseen. In Kaikki vapaudesta, eds. Kari Enqvist, Ilari Hetemäki,
    Teija Tiilikainen. 212-226. Gaudeamus p. 311.
  • Vesakoski O. (2009). Local and sexual divergence in host-use traits and anti-predator adaptations in the marine herbi-vore Idotea balthica. Annales Universitatis Turkuensis A II 235, Turku. p. 111

Contact Information

Email: outi.vesakoski(at)utu.fi