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Signatures of a shadow biosphere
Paul C W Davies1, Steven A Benner, Carol E Cleland
1BEYOND: Center for Fundamental Concepts in Science, Arizona State University, Tempe, Arizona 85287-1404, USA. paul.davies@asu.edu
Astrobiology
|March 19, 2009
Summary
Scientists explore the potential for "shadow biospheres" of unusual life forms on Earth. This research considers how to detect these hidden ecosystems, which may have arisen independently from known life.
Area of Science:
- Astrobiology
- Origin of Life Research
- Biogeochemistry
Background:
- Extraterrestrial life may differ significantly from terrestrial life.
- The possibility of independent origins of life on Earth, forming 'shadow biospheres,' is underexplored.
- Current astrobiological focus is primarily on alien life, neglecting potential 'weird life' on our own planet.
Purpose of the Study:
- To investigate the potential existence of shadow biospheres on Earth.
- To identify possible biosignatures associated with hypothetical 'weird life' forms.
- To propose strategies for detecting evidence of a shadow biosphere.
Main Methods:
- Conceptual analysis of life's origins and potential diversity.
- Review of astrobiological principles and biosignature detection.
- Development of hypothetical detection frameworks for novel biochemistry.
Main Results:
- The concept of a shadow biosphere on Earth is plausible if life arises readily.
- Unique metabolic pathways or molecular structures could serve as biosignatures.
- Existing detection methods may not be sensitive to all forms of 'weird life.'
Conclusions:
- Earth may harbor undiscovered biospheres with distinct biochemistry.
- Further research into alternative biochemistries is crucial for astrobiology.
- Developing novel detection strategies is essential to find evidence of shadow biospheres.
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