Traces of microbial life and activity in Arctic endolithic habitats

Arctic endolithic (rock-dwelling) microbial communities are a key interface between biology and geology, yet their diversity, distribution, and metabolic capabilities remains vastly unexplored. The Arctic's sensitivity to changes in climate makes it especially imperative to understand the interactions between microorganisms and environmental conditions to enable the prediction of future ecological changes. Furthermore, endolithic communities are vital for our understanding of the parameters for life in extreme environments. Despite subzero temperatures, nutrient shortage, and a lack of liquid water, these "islands of microbial life" thrive beneath the surface of translucent rocks, where they are protected from the harsh conditions of the Arctic. However, little is known about the diversity and ecology of such communities in the Arctic. The aims of this PhD project are therefore two-fold: 1) to characterise the composition and functional adaptations of microbial communities present in Arctic endolithic habitats, and 2) to utilise novel imaging and spectroscopy methods to investigate microbe-mineral interactions and biosignatures associated with these microbial communities. This project will involve collaboration within a multidisciplinary team including the Natural History Museum and the London Centre for Nanotechnology, addressing key cross-disciplinary questions about life in extremes and the strategies needed to search for past life in the geological record on Earth, and potentially elsewhere in the Solar System.