The effects of microhabitat temperature in phenotypic variation across B. antarctica populations

Environmental conditions are the major drivers of species distribution, and terrestrial Antarctica arguably presents the most dramatic challenges for its inhabitants. Many animals rely on acclimation to enhance their stress tolerance to face unfavorable conditions. Some animals can also rely on their phenotypic plasticity to respond to these unfavorable conditions without the need to slowly experience increasing levels of stress to enhance their stress tolerance (i.e., acclimate). Belgica antarctica can rely on both types of strategies, but since they evolved to live in a habitat with such dramatic environmental changes as Antarctica, they are very sensitive to any type of stress (e.g., a sudden drop in temperature, or a bout of high-speed wind). Studying the extent to which B. antarctica rely on each of these strategies to survive and how environmental variation can shape this species’ biology across distinct populations (i.e., that might experience distinct selective pressures) is important to help us better understand how polyextremophiles adapt and evolve while inhabiting extreme environments. This project focused on studying freeze tolerance in B. antarctica populations populations within Cormorant Island that inhabited three distinct microhabitats over the course of the summer season (January-March).