I always find it theraputic to renew my awareness of the fact that humans as we know them occupy only an eyeblink in the timeline of complex life on this planet. If just the period in which complex organisms arose is thought of in terms of a single year, fish would have appeared in January, land animals in March, dinosaurs in June, monkeys in December and humans late on New Year’s Eve.
This graphic from the Nov. 7 Science section of the NYTimes, prepared by Robert Rohde at Berkeley, is so striking that I wanted to pass it on. Carbon dioxide levels have been much higher at various times in the past than they are now. The accompanying article helps frame the debate over carbon dioxide in the atmosphere.