Biological activity has shaped environments across Earth with varying degrees of impact throughout geological time, which complicates efforts to distinguish signs of life in preserved structures. This challenge is further compounded in the ancient rock record, where diagenesis and alteration obscure biological signatures. To overcome these obstacles, it is necessary to understand the underlying processes that produce chemical and morphological features indicative of life. Traditional approaches to studying biological signatures in deep time typically focus on the binary question of “life” versus “non-life,” often guided by predefined questions. Here, we emphasize a shift toward process-driven research that explores the relationships between fundamental scientific principles that govern these features, rather than traditional outcome-focused approaches. We lay groundwork for a more comprehensive exploration of life’s role in shaping the rock record by addressing practical challenges and providing approaches for implementation.
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