Discriminating between extinct and extant life detection: implications for future Mars missions

The search for biosignatures on Mars has been a high priority for astrobiology. The approach to detecting putative biosignatures has largely been focused on chemical analysis. However, this approach has limited the characterization of extant life, preventing differentiation between extinct and extant biosignatures. Detecting an extant Martian lifeform requires an incorporation of approaches focused on identification biological features. Identifying potential features of life, such as growth or reproduction, can contribute evidence necessary to identify extant biosignatures. While an unambiguous extant biosignature might not be possible with this these biological techniques, in conjunction with flight tested instrumentation, the combined data can provide supporting evidence to attribute a biosignature to an extinct or extant lifeform. With upcoming initiatives, such as the Mars Sample return and Mars Life Explorer, the incorporation of extant life specific analysis is paramount for the future of Mars exploration.