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Science Forum Index » Bio Evolution Forum » Notes worth thinking about
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| Guest |
 Posted: Sun Feb 11, 2007 7:41 pm |
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1. Did life begin way before 4.0 bya? Jan. 01 report found
a tiny crystal of zircon in NW Australia dated at 4.4 bya. Anaylsis
of the oxygen isotopes suggest that the crystal could ONLY have
orginated in a wet, low-temperature environment. Was the early
earth a water-world so long ago? That really pushes things back.
2. Thermal vents happen at the surface too. Perhaps a mix of
two was involved in the origin process. That way one can
have both the advantages of vents and the UV/heat cycle.
3. Wachtershauser suggests retracing the Krebs cycle to see how
it began. I suggest seeing how a uv/sun cycle could have produced
a Krebs cycle in reaction to that heat cycle on the early earth.
4. UV may have had a key in determining the preferred handedness,
"It turns out that UV light that is circular polarized can selectively
destroy left-handed or right-handed molecules, depending on the
direction of the polarization. If an initially racemic mixture of
amino acid molecules in space were bathed in circular polarized
UV, the result would be an eventual bias of either the left-handed
or the right-handed forms" Life Everywhere, D Darling. |
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| Tom Hendricks |
| Posted: Mon Feb 12, 2007 9:40 am |
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Guest
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TomHendricks474@cs.com wrote:
Quote: 1. Did life begin way before 4.0 bya? Jan. 01 report found
a tiny crystal of zircon in NW Australia dated at 4.4 bya. Anaylsis
of the oxygen isotopes suggest that the crystal could ONLY have
orginated in a wet, low-temperature environment. Was the early
earth a water-world so long ago? That really pushes things back.
Here's a good website article on the zircon evidence.
http://science.nasa.gov/headlines/y2001/ast17jan_1.htm |
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