How lowly bacteria froze Earth solid: Scenarios that led
to snowball episode could happen again, scientists warn
By R. R. Britt, MSNBC, Aug. 1, 2005 [msnbc.msn.com]

Evolutionary Accident Probably Caused The Worst Snowball Earth
PhysOrg.com, VA, Aug. 2, 2005, [www.physorg.com]

The article is:

Kopp, R. E., Kirschvink, J. L., Hilburn, I. A., and Nash, C. Z.,
2005, The Paleoproterozoic snowball Earth: A climate disaster
triggered by the evolution of oxygenic photosynthesis.
Proceddings of the National Academy of Science. (August 1, 2005)
10.1073/pnas.0504878102 [www.pnas.org]

"The past is never dead. It's not even past."
William Faulkner, Act 1, Scene III, Requiem for a Nun (1951)