Washington: Where did life on Earth start? -- This age-old question seems to have a new answer. Life may have originated between sheets of mica that were layered like
the pages in a book, say scientists.
A team at University of California has come up with the so-called "life between the sheets" mica hypothesis which is described in an upcoming 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 progenitors to cells.
Provided with the right physical and chemical environment in the structured compartments to survive and evolve, the molecules eventually reorganised into cells, while still sheltered between mica sheets.
According to lead scientist Helen Hansma, as mica surfaces are hospitable to living cells and to all the major classes of large biological molecules, including proteins, nucleic acids, carbohydrates and fats, the mica hypothesis is consistent with other well-known hypotheses that propose life originated as RNA, fatty vesicles or primitive metabolisms.
"Mica world might have sheltered all the ancient metabolic and fat-vesicle and RNA `worlds`," she said.