Talk:Texans for a Better Science Education

Oxygen, life, and iron
Elaborating on the point against
 * Photodissociation of water vapor has been a source of oxygen since the Earth formed, and there is substantial geologic evidence that a significant amount of oxygen existed in the atmosphere prior to the advent of photosynthesis. Oxygen breaks down amino acids and sugars that are postulated to have formed!

Oxygen in concentrations to be harmful to sugars and amino acids would have also been 'harmful' to free iron. Most of banded iron formations where laid down 2.5 - 1.8 billion years ago. At this point, the free iron dissolved in the oceans precipitated out. More on this at http://www.talkorigins.org/indexcc/CB/CB035_1.html. Fossil Eukaryotic are found at 3.5 Bya. Fossils of early life predates any evidence of molecular oxygen in any significant quantity. --Shagie 18:54, 9 July 2008 (EDT)