BergZ writes: The Ordovician ice age happened 444 million years ago, and records have suggested that CO2 levels were relatively high then. But when Seth Young of Indiana University in Bloomington did a detailed analysis of carbon-13 levels in rocks formed at the time, the picture that emerged was very different. Young found CO2 concentrations were in fact relatively low when the ice age began.
"Card readers? We don't need no stinking card readers."
-- Peter da Silva (at the National Academy of Sciencies, 1965, in a
particularly vivid fantasy)