Astrobiology in Deep Time

This theme investigates ancient biosignatures and the intersection between astrobiology and palaeontology

Astrobiology includes the study of the origin and evolution of life on Earth, the distribution of life across time (as well as space), and the search for fossils on Mars and other worlds. These topics lie at the intersection of astrobiology and palaeontology. Work under the Deep Time theme seeks to understand how geological biosignatures such as fossils can form and endure across billions of years, and how they might be recognised and identified in very ancient materials. This theme is the main focus of the McMahon Group, who have, for example:

• shown that life in dark subsurface environments outweighed life at the Earth's surface for at least half the history of the biosphere (link to paper)
• discovered ancient biosignatures in Mars-analogue materials such as gypsum veins (link to paper)
• highlighted the difficulty of distinguishing ancient fossils from "chemical gardens" and other abiotic impostors that might form in Mars-relevant geochemical environments (link to paper).