That age-old question, "where did life on Earth start?" now has a new answer. If the life between the mica sheets hypothesis is correct, life would have originated between sheets of mica that were layered like the pages in a book.
The so-called "life between the sheets" mica hypothesis was developed by Helen Hansma of the University of California, Santa Barbara, with funding from the National Science Foundation (NSF). This hypothesis was originally introduced by Hansma at the 2007 annual meeting of the American Society for Cell Biology, and is now fully described by Hansma in the September 7, 2010 issue of Journal of Theoretical Biology.
According to the "life between the sheets" mica hypothesis, structured compartments that commonly form between layers of mica--a common mineral that cleaves into smooth sheets--may have sheltered molecules that were the progenitors to cells. Provided with the right physical and chemical environment in the structured compartments to survive and evolve, the molecules eventually reorganized into cells, while still sheltered between mica sheets.
Mica chunks embedded in rocks could have provided the right physical and chemical environment for pre-life molecules and developing cells because:
Mica compartments could have held, protected and sheltered molecules, and thereby promoted their survival. Also, mica could have provided enough isolation for molecules to evolve without being disturbed and still allow molecules to migrate towards one another and eventually bond together to form large organic molecules. And mica compartments may have provided something akin to a template for the production of a life form composed of compartments, which are now known as cells.
Mica sheets are held together by potassium. If high levels of potassium were donated by mica sheets to developing cells, the high levels of potassium found in mica sheets could account for the high levels of potassium curre
|Contact: Lily Whiteman|
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