greater depths the descending water boils and provides steam and heat so that (3) salts continue to slowly dissolve, rise with steam and deposit as evaporites on a cooler nearby wall, ceiling or as in this model, a shelf. (Image credit: the authors).
Models of the sulfur and ammonia oxidizing environments are available in a previous study [1.3].
1.7 Conclusions
The worldwide abundance of fumaroles compared to hot springs make this an ideal choice as a habitat for early development of life on Earth. These primitive steam habitats characterized by two extreme physical features, low pH and high temperature, typically flourish with Archaea. The fact that these organisms seem to have persisted from the earliest times argues that they may represent the type of living organism that could have evolved else-where beyond planet Earth. Steam caves/vents, while limited in diversity [1.7], represent and remain a rich and potentially useful and reliable source for isolation of unknown and unexplored life forms.
Acknowledgments
We thank the following National Park Service members for assistance with access to collections; Michael Magnuson, Wildlife Biologist, Lassen Volcanic National Park; Rhonda Loh, Chief of Natural Resources Management and Keola Awong, Cultural Specialist and Native Hawaiian Liaison for facilitating our collections of fumaroles and supporting our research efforts in Hawai’i Volcanoes National Park. Jeff Sutton and Aaron Pietruszka, US Geological Survey, offered guidance on the Geology/Geochemistry of our collection areas. Benno Spingler prepared Figure 1.1; Xzayla Zabiti and Anthony Correy provided ideas and participated in the design and construction of the steam collector. We thank our graduate students, Dean Ellis, Courtney Benson, Kate Wall, and Jenny Cornell, and undergraduates, Christa Anderson and Wendy Gutierrez. The authors acknowledge the assistance of Steve Barlow, and use of equipment at the San Diego State University Electron Microscopy Facility acquired by NSF Instrumentation grant DBI-0959908, SB Barlow. Ingrid Niesman, Director of the SDSU Electron Microscope Laboratory facilitated the SEM work. Generous contributions of Schering-Plough Biopharma assisted this study.
References
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1 * Corresponding author: [email protected]
2 Richard L. Weiss Bizzoco: https://www.researchgate.net/profile/Richard_Bizzoco
3 Scott T. Kelley: https://scholar.google.com/citations?user=oHXnsCEAAAAJ&hl=en
2
Rio Tinto: An Extreme Acidic Environmental Model of Astrobiological Interest
Ricardo Amils 1,2* and David Fernández-Remolar3,4
1 Centro de Astrobiología (CAB, CSIC-INTA), Torrejón de Ardoz, Spain
2 Centro de Biología Molecular Severo Ochoa (CBMSO, CSIC-UAM), Universidad Autónoma de Madrid, Madrid, Spain
3 State Key of Lunar and Planetary Sciences, Macau University of Science and Technology, Macau SAR, People’s Republic of China
4 CNSA Macau Center for Space Exploration and Science, Macau SAR, People´s Republic of China
Abstract
Among extremophiles, acidophiles are of special interest because their chemolithotrophic metabolism obtains energy from reduced minerals, thus creating the extreme acidic conditions in which they thrive. Rio Tinto is a 92 km long extreme acidic environment, which is the product of the metabolic activity of chemolithotrophic microorganisms thriving in the high concentration of metal sulfidic minerals existing in the Iberian Pyrite Belt. An extensive geomicrobiological characterization of the Tinto