This thesis studies one of the most pressing challenges to human existence — climate change and ecological breakdown. It does so by problematising the gaps in responsibility and political awareness of non-human entities that are critical to planetary stability. I explore this rift by leveraging the concept of “personhood” as a potential tool to force political responsibility for vulnerable parts of the ecosystem. This is realised by using a case study: the personhood of phytoplankton, microscopic photosynthesisers that are ubiquitous in our oceans and underpin global food and carbon systems. The result of this theoretical exercise is a more nuanced understanding of the need for political awareness and responsibility for parts of the earth system, and also the limitations of our current political systems to do so.