From Finland to Antarctica: Tracking Cellular Energy in Birds

From the frozen polar regions to suburban back gardens, birds of every shape and size survive and thrive thanks to their unique physiology. Nina Cossin-Sevrin, a doctoral researcher in the Department of Biology at the University of Turku (UTU), is particularly interested in two distinct avian species in two very different locations for her research – wild great tits in Turku and king penguins in the French Southern Territories in the sub-Antarctic zone. “The idea of using two species was to investigate different questions,” she explains. “For example, I want to study the effects of environmental factors, and great tits have many chicks and a short breeding season [1.5 months]. But king penguins only have one chick (per breeding season) and a long breeding season [14 months]. Also, they have two peaks of hatching, so we can investigate differences between early-born and late-born chicks.”

Nina first arrived in UTU from France to undertake a six-month internship for her Master’s degree. As she enjoyed the experience so much, she applied to stay on and join Professor Suvi Ruuskanen’s group as a doctoral researcher in 2020. She appreciates the help and support that UTU provides as part of its doctoral programme. She has regular meetings with her two supervisors, and once a month, doctoral researchers get together and take it in turns to discuss their research and any challenges they’re facing. There are also extracurricular events. “A few months ago, all the PhD students went to Tvärminne Zoological Station – it’s like a research station – and the idea was to connect with each other and take part in something that was not work-related,” she says.

Every year doctoral researchers meet with an advisory committee meeting where they discuss their progress and upcoming work. “I think those meetings are really important,” she says. “They can give another perspective and advice on your project that’s really valuable.” The university also offers plenty of optional courses that allow doctoral researchers to enhance their skills in a particular area, for example, statistics, fieldwork or pedagogy, to name a few. And UTU researchers have access to excellent infrastructure and lab equipment for their work at a modern facility nearby called BioCity.

The main focus of Nina’s research is on bird physiology. “The idea of my project is to study what environmental conditions affect the ability of birds to create energy from nutrients and oxygen,” she says. Living cells need to produce energy, and energy production varies not only among birds of different species, but also between individual birds from the same species. Why this variation exists and what causes it is something she’s trying to understand. She’s already published some exciting findings from her research on great tits. She examined the influence of maternal hormones in eggs on chicks’ metabolism and growth. Levels of maternal hormones may fluctuate depending on genetic and environmental factors. “We found some effect caused by the corticosterone hormone, which is related to stress hormones, leading to decreased mitochondrial metabolism [mitochondria produce energy for cells].” This hormone also adversely affected body mass in female birds a few months after fledging.

To study king penguins, Nina had the good fortune to conduct fieldwork during a three-month-long expedition to the Crozet archipelago in the French Southern Territories. There she got to observe king penguins in the wild and collect samples and take measurements for her research. This expedition was a result of her collaborations with the French Polar Institute and the University of Strasbourg. She also received funding for the trip from a Maupertuis grant, which is a grant specifically aimed at strengthening Finnish-French scientific cooperation.

Nina enjoys the community atmosphere at UTU. It has a real international feel as it hosts around 2,000 doctoral researchers from over 70 countries. The university also takes great care to look after the well-being of its students. It runs a peer support project called “On My Mind” to ensure that people always have someone to talk to and nobody feels isolated. The International Staff Services team is on hand to provide helpful advice and information to doctoral researchers moving from abroad. Nina is pleased she joined UTU and enjoys the beautiful surroundings. She says, “Turku is quite a green city. There are lovely forests nearby. I really like the river too, and the sea is also not so far away. So the connection to nature is really nice.” She would definitely recommend that new doctoral researchers check out UTU’s 16 doctoral programmes, covering all disciplines.