Out of interest, how many "snowball earth" events were/are alleged?
I'm aware of the one just before the Cambrian explosion, & am dimly aware it wasn't the first. My reading suggests it may have been life itself that prevented the next "post" cambrian snowball, due to a change in gas concentrations, particularly oxygen.
------------------ Occam's razor is not for shaving with.
[This message has been edited by mark24, 03-04-2002]