Dr. Matthew Dodd is a geochemist who develops and applies novel geochemical tools to understand how carbon and nutrient cycles affect the long term habitability of Earth. In 2017 he discovered the oldest known fossils on Earth, which received global media attention. His current work focuses on studying changes in the global carbon, phosphorus and oxygen cycles in order to understand how these critical elements have shaped the evolution of Earth's atmosphere, climate, and the evolutionary history of life. A detailed understanding of the carbon, phosphorus and oxygen cycles will be critical in predicting the future habitability of Earth and of extraterrestrial planets.