Over four billion years ago, life began to take form on this nascent Earth. These simple cell life forms
inhabited a much harsher Earth than us, much wetter with sizzling ultraviolet rays. How did these simple cells become every complexity that inhabits the Earth today? This is a question humans have been asking for centuries.
A new study from NASA's Jet Propulsion Laboratory and the Icy World's team at NASA's Astrobiology Institute describes how naturally produced electrical energy at the sea floor may have given rise to life. While this hypothesis had already been proposed, (called the submarine alkaline hydrothermal emergence of life) the new report gathers decades of laboratory, field, and theoretical research into one grand idea.
The new theory, which can be called the 'water world' theory, proclaims life may have began inside warm, gentle springs on the sea floor, back when Earth's oceans covered the entire planet. This idea of hydrothermal vents being the place of the origin of life was first proposed in 1980 by other researchers. The vents they used in their study were called 'black smokers,' bubbling with hot acidic fluids. In contrast, the vents discussed in the water world theory are cooler, gentler, and percolate with alkaline fluids.
(A close-up of chimney structures created in the Icy Worlds lab at NASA's Jet Propulsion Laboratory, Pasadena, Calif. Chimney structures like these can be found on the sea floor, surrounding warm, alkaline hydrothermal vents.)
"Life takes advantage of unbalanced states of the on the planet, which may have been the case billions of years ago at the alkaline hydrothermal vents" said Michael Russel, who first hypothesized life began at alkaline hydrothermal vents back in 1989. Russel claims, "life is the process that resolves these disequilibria." Russell is the lead author of the new water world study, which was published in April's edition of Astrobiology.
Russell says the necessary experiments to determine evidence are extremely difficult to design and carry out. For now, the ultimate question of where life originated still remains unanswered.
Find the original article at: http://www.sciencedaily.com/releases/2014/04/140415195712.htm
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