Examining changes in foraging patterns during Dehnel phenomenon in the common shrew (Sorex araneus)
Ephemeral Resource Adaptations Research Group
What’s the project about? Animals living in temperate climates have evolved various strategies to cope with seasonal variations in temperature and resources. One of the most intriguing and poorly understood overwintering strategies is the Dehnel's Phenomenon, where certain small mammals undergo a programmed and reversible decrease in body size, including the mass of internal organs, to adapt to harsh winter conditions. The most remarkable change occurs in the brain, which can decrease in volume by up to 20% from summer to winter, and then increase by up to 10% from winter to spring. The reversible reduction of energetically costly tissues, such as the brain, leads to decreased food demands during periods of limited resources, but may also result in cognitive compromises. The common shrew (Sorex araneus) is considered the model species of this phenomenon. Previous studies on this species have shown that summer juveniles solve spatial navigation tasks faster than winter subadults. However, little is currently known about how Dehnel's Phenomenon might impact the foraging habits and patterns of the common shrew. Previous studies have focused on cognitive changes, but the potential alterations in foraging behavior during the seasonal cycle of body size reduction and expansion remain largely unexplored. During this bachelor project, you will analyze data from a foraging task conducted in captivity between 2021 and 2022. The data consists of video recordings of the tasks, which will be tracked to extract information about foraging patterns and efficiency. You will learn how to code videos for behavioral analyses using different software. Depending on the season when the project starts, there may be an opportunity to assist with fieldwork, such as catching new individuals and setting up new cognitive tasks for 2025. No prior experience coding in R or Python is necessary, as during this bachelor project you will gain hands-on experience in extracting and analyzing data.
Who can apply? The project is open to BSc students
