Oxygen on the young planet Earth
A new study is believed to have resolved a major debate about when oxygen began to be produced on earth and how long it took before oxygen levels were enough to support the growth of life.
Winthrop Professor Mark Barley, Centre for Exploration Targeting, The University of Western Australia
Nature, http://www.news.uwa.edu.au/201110204059/international/new-evidence-first-production-oxygen-earth
