ASSEMBLING PRIMITIVE CELLS UNDER MARTIAN GEOCHEMICAL CONDITIONS: Implications for the Origin and Survivability of Life on Early Mars
ASSEMBLING PRIMITIVE CELLS UNDER MARTIAN GEOCHEMICAL CONDITIONS: Implications for the Origin and Survivability of Life on Early Mars
Date
2022
Authors
Cary, Francesca Catherine Amy
Contributor
Advisor
Fagents, Sarah
Department
Earth and Planetary Sciences
Instructor
Depositor
Speaker
Researcher
Consultant
Interviewer
Annotator
Journal Title
Journal ISSN
Volume Title
Publisher
Volume
Number/Issue
Starting Page
Ending Page
Alternative Title
Abstract
Mars has been a focus for decades of investigation, as a place in the solar system that could have been habitable for life as we know it. Despite being habitable early in its history, it is important to consider whether Mars could have originated life; a necessary foundation for understanding whether life could have inhabited Mars. Little work has been done to directly apply current knowledge about the origin of life to the unique conditions and planetary history of Mars. This research aims to take into account broad geochemical differences between Mars and Earth, such as Mars’ iron-rich surface, and assess how conducive early Mars was to originating life. Iron, calcium, and magnesium cations are abundant in hydrothermal settings on both Earth and Mars, which constitute promising environments for life’s origin. The impacts of different ionic compositions on the assembly, stability, and destruction of primitive cells have been investigated for this thesis. Additionally, we investigate other components in ancient hydrothermal settings that could have increased the stability and survivability of primitive cells. We find that iron destabilizes primitive cell membrane formation less than does calcium. The concentrations of cations required to completely destabilize primitive membranes are higher than those found in natural settings on Earth, but could potentially have reached these high concentrations on Mars as a consequence of the loss of surface water. In addition, dehydration-rehydration cycles of primitive membranes in the presence of RNA stabilize them against cations in solution. High concentrations of cations in solution thus could have functioned as a significant selective barrier on Mars. Interaction of membrane vesicles and functional polymers, which stabilize primitive cells against changes in the environment, could have been a mitigating factor. This work initiates an avenue of Mars astrobiology research that considers how cellular life may have evolved under the distinct planetary conditions and selective factors on Mars.
Description
Keywords
Biogeochemistry,
Planetology,
astrobiology,
early Earth,
hydrothermal,
Mars,
origin of life,
prebiotic chemistry
Citation
Extent
93 pages
Format
Geographic Location
Time Period
Related To
Table of Contents
Rights
All UHM dissertations and theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission from the copyright owner.
Rights Holder
Local Contexts
Collections
Email libraryada-l@lists.hawaii.edu if you need this content in ADA-compliant format.