Terrestrial Ecosystems as Probable Analogues of Extraterrestrial Ones

This paper examines the issues of correlating some terrestrial ecosystems with hypothetical environments and processes on other planets and their moons. Recent studies of modern extremophiles suggest the need to re-evaluate established ideas about the ranges of physicochemical conditions suitable for accommodating life. Soda lakes may be considered as equivalents of local ephemeral, potentially habitable, ponds of cometary origin both on the early Earth (in the first ~0.5 Gyr, i.e., before the formation of the hydrosphere) and on the surface of other Solar System bodies. Studies of the Earth’s paleosols allow modelling of the possible past for Mars. The permafrost biota is not considered in the context of this study.