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The energy expansions of evolution.
Olivia P Judson1,2,3
1Freie Universität Berlin, Institute of Biology, Königin-Luise-Strasse 1-3, D-14195 Berlin, Germany.
Nature Ecology & Evolution
|August 17, 2017
Summary
Life on Earth evolved through five energetic epochs, driven by new energy sources like sunlight, oxygen, and fire. This expansion of energy availability increased ecosystem complexity and transformed the planet.
Area of Science:
- Astrobiology
- Geochemistry
- Evolutionary Biology
Background:
- The Earth's history is marked by distinct energetic epochs.
- Life forms evolve to exploit novel energy sources, shaping planetary environments.
Purpose of the Study:
- To outline the five energetic epochs in the life-Earth system history.
- To explore how energy source evolution influences life and planetary changes.
Main Methods:
- Historical analysis of energy sources available to life.
- Examination of evolutionary events and their impact on energy exploitation.
- Interdisciplinary review of life-Earth system interactions.
Main Results:
- Identified five energetic epochs: geochemical, sunlight, oxygen, flesh, and fire.
- Oxygen, flesh, and fire are products of evolutionary events.
- Expanding energy sources correlate with increased ecosystem diversity and complexity.
Conclusions:
- Energy availability has driven major transformations in the life-Earth system.
- An energy-centric view reveals patterns in intertwined life and Earth histories.
- This framework can inform the search for life-planet systems beyond Earth.
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