Drastic Environmental Change on Mars: Applying the Lessons Learned on Earth
Abstract
Rapid and drastic environmental change has occurred frequently on Earth, posing a critical challenge to life. However, directional selection has overcome those challenges and driven life on our planet to ever increasing diversity and complexity. Based on our knowledge of the natural history of Earth, the effect of drastic environmental changes on a planet's biosphere can be attributed to three main factors: (1) the nature and time scale of change, (2) the composition of the biosphere prior to change, and (3) the nature of the environment following the change. Mars has undergone even larger environmental changes than Earth, from habitable conditions under which the origin of life (or transfer of life from Earth) seem plausible, to a dry and cold planet punctuated by wetter conditions. Given its planetary history, life on Mars could have retreated to a psychrophilic lifestyle in the deep subsurface or to environmental near-surface niches, such as hydrothermal regions and caves. Further, strong directional selection could have pushed putative martian life to evolve alternating cycles between active and dormant forms, as well as the innovation of new traits adapted to challenging near-surface conditions (e.g., use of H2O2 or perchlorates as antifreeze compounds).
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2014
- Bibcode:
- 2014AGUFM.P11C3769F
- Keywords:
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- 1605 Abrupt/rapid climate change;
- GLOBAL CHANGE;
- 1630 Impacts of global change;
- GLOBAL CHANGE;
- 5220 Hydrothermal systems and weathering on other planets;
- PLANETARY SCIENCES: ASTROBIOLOGY;
- 5225 Early environment of Earth;
- PLANETARY SCIENCES: ASTROBIOLOGY