ECR Spotlight is a series of interviews with early-career authors from a selection of papers published in Journal of Experimental Biology and aims to promote not only the diversity of early-career researchers (ECRs) working in experimental biology but also the huge variety of animals and physiological systems that are essential for the ‘comparative’ approach. Sara Nørris Christoffersen is an author on ‘ Strong acclimation effect of temperature and humidity on heat tolerance of the Arctic collembolan Megaphorura arctica’, published in JEB. Sara is a PhD student in the lab of Simon Bahrndorff at Aalborg University, Denmark, investigating how climate change affects invertebrates in the Arctic terrestrial environment.
Sara Nørris Christoffersen
How did you become interested in biology?
For as long as I can remember, I have always found nature fascinating. This fascination was in great part nurtured throughout my childhood by my grandparents and other family members bringing me to the zoo, to natural museums and out into nature. Through high school, this interest was further developed through different courses, but it wasn't until my gap year when I volunteered for a wildlife rescue centre that I realised that I had found my calling in biology.
Describe your scientific journey and your current research focus
After my gap year, I enrolled at Aalborg University to study biology where I completed both my bachelor's and master's degrees. Aalborg University is unique in that the education is centred around Problem Based Learning meaning that for every semester students conduct experiments or field work that culminates in a scientific report. This sparked my passion for research in the early semesters of my bachelor’s degree, because I got to experience what research looked like on a smaller scale. During both my bachelor’s and master’s, I worked with invertebrates and the direct and indirect effects of climate change, so when I was offered the opportunity to do an integrated PhD centred around just this, by my supervisor Simon Bahrndorff, I naturally accepted. I started the PhD in 2022 and am now halfway through.
My current research focus is how climate change affects the Arctic terrestrial environment. More specifically, I investigate Arctic arthropods and how they respond to different climate scenarios both in laboratory experiments and in the field.
A laboratory population of the Arctic springtail Megaphorura arctica. This species is often found aggregated under stones and vegetation under bird cliffs and along seashores. Eggs can be seen centrally in the picture.
A laboratory population of the Arctic springtail Megaphorura arctica. This species is often found aggregated under stones and vegetation under bird cliffs and along seashores. Eggs can be seen centrally in the picture.
How would you explain the main findings of your paper to a member of the public?
When looking at Arctic arthropod species’ thermal tolerances, the majority of studies have focused on how these species respond to cold stress and associated drought stress, meaning that the heat tolerance of Arctic arthropod species is a relatively unexplored field, especially when seen in combination with drought stress. In this paper, I investigated the heat stress tolerance of the Arctic springtail Megaphorura arctica and found that the effect of a higher temperature on its own on the heat tolerance was rather complex and dependent on the duration of exposure. I also saw that there was a marked interaction between high temperatures and low humidities, which resulted in decreased heat stress tolerance in the springtail. This interaction could also be seen when investigating how fluctuating temperatures affected the heat tolerance of the species. These results highlight the importance of taking multiple environmental factors into account when trying to understand how species will respond and adapt to future climate changes.
What do you enjoy most about research, and why?
My favourite part of research is that I get to geek out about and deep dive into subjects that I find fascinating. More practically, I most enjoy brainstorming experiments and coming up with designs for investigating specific research questions. I also thoroughly enjoy data analysis because this is where all your work comes to fruition. Here, you get to see the patterns emerge and you can start answering your hypotheses. Overall, I just think it is really cool to be able to contribute with new knowledge to a field that I am so passionate about.
What is the most important lesson that you have learned from your career so far?
There are certain challenges when working with Arctic species, as they are very difficult to keep in the laboratory (because it is hard to imitate natural conditions in the lab) and the period in which they are active during summer is very short. With M. arctica, which I worked with for this paper, I was able to keep them in the laboratory for quite a long time. Even though the species managed to lay eggs (as can be seen centrally on the picture), which was quite exciting, these never hatched. This meant that I had to conduct as many experiments as I could in the period in which I was able to keep them in the lab. Furthermore, when working in the field, I have learned to not only have a plan A, but also a plan B, C and D ready, because in the Arctic there is a very short window in which you have a chance to collect samples and perform experiments in and if something does not go as planned you need to quickly be able to reroute. When you are working in an area as remote as the south of Greenland, you also only have access to whatever equipment you brought with you, which further emphasises the need for planning for every possible scenario when preparing for the field season.
Sara Nørris Christoffersen's contact details: Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg East, Denmark.
E-mail: [email protected]
