I grew up in Rotterdam, a large modern city and industrial area in the Netherlands. Luckily, I lived near some parks and lakes so I could escape into green areas most of the time, and I would also often venture into nature areas further afield, particularly with my father, who had studied biology. When I was around twelve years old, I joined a Dutch youth association for nature study (Nederlandse Jeugdbond voor Natuurstudie; NJN), an association for and by young people aged 12 to 25 who like to study nature. Together with them I had a great childhood, and I joined and helped organise nature camps and excursions throughout the year with different themes, including plants. These were really wonderful times, and I would often spend the entire summer living in tents and venturing into nature on foot or by bicycle and most of all being amongst other young people with similar mindsets and interests!

In my BSc at the University of Groningen, I got the opportunity to join in on two long summer fieldwork seasons at the Dutch Arctic Station in Ny-Ålesund, Svalbard. Spending time in this arctic multi-national science-village with fieldwork every day really made me fall in love with the high latitudes and looking at the small organisms inhabiting the tundra, in particular bryophytes, small vascular plants and insects. In my BSc I also did  my first project on mosses: a short but interesting study on Sphagnum and how it copes with different ions and pH conditions, which we investigated using microelectrode ion flux measurements, as well as measuring photosynthesis and oxygen production.

I became eager to study ecology and evolution using molecular tools, and to learn more about higher latitude regions. After studying my MSc with a combined Nordic master program in Norway, Iceland, Denmark and the Faroe Islands, I continued to do my PhD at the University of Cambridge and the British Antarctic Survey on the evolutionary history of bryophytes in Antarctica. During these years I really fell in love with mosses, and their amazing capabilities to live in harsh environments, their evolutionary age, their incredible life cycle and capabilities to disperse across long distances. Although I never developed great skills in bryophyte taxonomy (yet!), I have found it extremely interesting to dive into their ecology, evolution, population biology and biogeography.

My main focus was on finding out more about the geographic origin and age of mosses in Antarctica, and their responses in relation to past dramatic climatic shifts. I mainly used dried herbarium collections in combination with phylogenetic, population genetic and molecular dating approaches (using fossils and rates) in order to understand how, from where and when bryophytes dispersed. These studies revealed evidence that the modern Antarctic moss flora consists of a mix of old survivors (e.g., the endemic Schistidium antarctici) and recent arrivals. Other studies I did during these years on very common and globally widespread moss species (e.g., Ceratodon purpureus) revealed how their populations across the globe are highly aligned with (and likely highly influenced by) global atmospheric currents. Another project on bipolar mosses revealed that the dispersal events that led to their highly disjunct distribution pattern mainly occurred from the north to the south, and only one example revealing the opposite direction of dispersal. Molecular dating analyses suggested that these dispersals across the equator are likely rare events, occurring on multi-million-year timescales.

Finding out the stories of how and when a particular species arrived somewhere is fascinating to me, as it feels as if I am unravelling a puzzle, revealing that even tiny, little organisms can possess such an incredible history of how they got to where they are now. It is also motivating to me as the insights of such studies can have implications for conservation (e.g. the need of more protected areas of ice-free regions in Antarctica) and reconstructing Antarctica’s past climate (e.g. finding out where there might have been ice-free “refugial” areas to allow for survival throughout glacial periods).

Since 2019, I have been working as a postdoctoral researcher at the Natural History Museum of Denmark and the University of Copenhagen, focusing on the biogeography of plants in Greenland and their responses to past and future climate change. Unfortunately, I don’t work on bryophytes as much as I would like, and in the future, I would like to do more research on bryophytes again. I also like to add that I rarely experienced a more welcoming community than the bryologist community; people have always been extremely warm and helpful, and there is a highly collaborative atmosphere, which really appeals to me!

Selected publications:

• Biersma, E.M., Convey, P., Wyber, R., Robinson, S.A., Dowton, M., Van De Vijver, B., Linse, K., Griffiths H. & Jackson, J.A. (2020) Latitudinal biogeographic structuring in the globally distributed moss Ceratodon purpureus. Frontiers in Plant Science. 11:502359. https://doi.org/10.3389/fpls.2020.502359
• Biersma E.M., Jackson, J.A., Stech, M., Griffiths, H., Linse, K. & Convey, P. (2018) Molecular data suggest long-term in situ Antarctic persistence within Antarctica’s most speciose plant genus, Schistidium. Frontiers in Ecology and Evolution. 6, 77. https://doi.org/10.3389/fevo.2018.00077
• Biersma E.M., Jackson, J.A., Bracegirdle T.J., Griffiths, H., Linse, K. & Convey, P. (2018) Low genetic variation between South American and Antarctic populations of the bank-forming moss Chorisodontium aciphyllum (Dicranaceae). Polar Biology, 1-12. https://doi.org/10.1007/s00300-017-2221-1 ?
• Lewis, L.R., Biersma, E.M., Carey, S.B., Holsinger, K., McDaniel, S.F., Rozzi, R., & Goffinet, B. (2017) Resolving the northern hemisphere source region for the long-distance dispersal event that gave rise to the South American endemic dung moss Tetraplodon fuegianus. American Journal of Botany. 104(11), 1651-1659. https://doi.org/10.3732/ajb.1700144
• Biersma E.M., Jackson, J.A., Hyvönen, J., Koskinen, S., Linse, K., Griffiths, H. & Convey, P. (2017) Global biogeographic patterns in bipolar moss species. Royal Society Open Science. 4: 170147. http://dx.doi.org/10.1098/rsos.170147
• Lewis, L.R. & Ickert-Bond, S., Biersma, E.M., Convey, P., Goffinet, B., Hassel, K., Kruijer, H., La Farge, C., Metzgar, J., Stech, M., Villarreal, J.C. & McDaniel, S.F. (2017) Future directions and priorities for Arctic bryophyte research. Arctic Science(ja). https://doi.org/10.1139/as-2016-0043
• Pisa, S. & Biersma, E.M., Convey, P., Patiño, J., Vanderpoorten, A., Werner, O. & Ros, R.M. (2014) The cosmopolitan moss Bryum argenteum in Antarctica: recent colonisation or in situ survival? Polar Biology, 37(10), 1469-1477. https://doi.org/10.1007/s00300-014-1537-3