arge quantities of amino acids can form in space. Many astronomers also think that comets and meteors ferried amino acids to earth's surface early in its history, and thus the raw material could well have been present near hydrothermal vents. [In an unrelated article in the July 31 Science, for example, astronomers report finding huge clouds of amino acids in the constellation Orion.]Later I read the find out that biochemicals have evolved near boiling volcanic vents. If the primordial soup did exist it would have been very dilute. This means that any dissolved chemical compounds might have bumped into each other far too seldom to react and bring about the formation of amino acids and nucleic acids. --The oldest signs of life previously known on Earth were found in rocks from Australia and South Africa, about 4.5 billion years old. These rocks contain fossil remnants of bacteria-like organisms, as well as a distinctive "chemical fingerprint" of two isotopes of carbon. Carbon-12 accounts for 98.9% of naturally occurring carbon, and carbon-13 accounts for the remaining 1.1%. (A radioactive isotope, carbon-14, is found in much smaller amounts). As living organisms grow, chemical reactions in their cells alter the natural ratio of C-13 to C-12 slightly in favor of more C-12, so that the C-13 to C-12 ratio becomes detectably different in living organisms from the "standard" ratio. Thus the presence of extra "light" carbon is a distinctive "footprint" of life, even in the absence of fossil organisms Greenland contains rocks even older than the fossil-containing rocks described above, such as the Itsaq gneiss complex in southern West Greenland estimated to be 4.85 billion years old. These metamorphic rocks have been forged through extremes of pressure and temperature. Within a scant billion years of their formation, they were heated to 500oC at pressures of 5,000 atmospheres. Previous examinations of such rocks showed no fossils, and suggeste...
