Pumice Proposed as Home to the First Life Forms
ScienceDaily (Oct. 5, 2011) — The glassy, porous, and once gas-rich rock called pumice may have given rise to early life forms, according to a provocative new hypothesis on the origin of life published in Astrobiology.
Pumice. (Credit: © Jakub Cejpek / Fotolia)
Martin Brasier, Richard Matthewman, and Sean McMahon, University of Oxford (U.K.), and David Wacey, University of Western Australia (Crawley), contend that pumice has "four remarkable properties" that would enable it to have had "a significant role in the origin of life and provided an important habitat for the earliest communities of microorganisms." They describe those four properties in detail in the article "Pumice as a Remarkable Substrate for the Origin of Life."
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Pumice as a Remarkable Substrate for the Origin of Life
To cite this article:
Martin D. Brasier, Richard Matthewman, Sean McMahon and David Wacey. Astrobiology. September 2011, 11(7): 725-735. doi:10.1089/ast.2010.0546.
Published in Volume: 11 Issue 7: September 16, 2011
Online Ahead of Print: August 31, 2011
Martin D. Brasier,1 Richard Matthewman,1 Sean McMahon,1 and David Wacey2,3
1Department of Earth Sciences, University of Oxford, Oxford, UK.
2Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, Crawley, Australia.
3School of Earth and Environment, The University of Western Australia, Crawley, Australia.
Address correspondence to:
Martin Brasier
Department of Earth Sciences
Oxford University
South Parks Road
Oxford OX1 3AN,United Kingdom
E-mail: martinb@earth.ox.ac.uk
Submitted 11 September 2010
Accepted 19 February 2011
Abstract
The context for the emergence of life on Earth sometime prior to 3.5 billion years ago is almost as big a puzzle as the definition of life itself. Hitherto, the problem has largely been addressed in terms of theoretical and experimental chemistry plus evidence from extremophile habitats like modern hydrothermal vents and meteorite impact structures. Here, we argue that extensive rafts of glassy, porous, and gas-rich pumice could have had a significant role in the origin of life and provided an important habitat for the earliest communities of microorganisms. This is because pumice has four remarkable properties. First, during eruption it develops the highest surface-area-to-volume ratio known for any rock type. Second, it is the only known rock type that floats as rafts at the air-water interface and then becomes beached in the tidal zone for long periods of time. Third, it is exposed to an unusually wide variety of conditions, including dehydration. Finally, from rafting to burial, it has a remarkable ability to adsorb metals, organics, and phosphates as well as to host organic catalysts such as zeolites and titanium oxides. These remarkable properties now deserve to be rigorously explored in the laboratory and the early rock record. Key Words: Pumice—Volcanoes—Biominerals—Origin of life. Astrobiology 11, 725–735.
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