Several years ago, paleontologist Dewey M. McLean stepped to the podium at a conference on the climatological effects of volcanoes. The silver-haired professor from the Virginia Polytechnic Institute looked out over the packed house like a pastor surveying his flock. He was about to deliver a sermon— well, a paper actually—that would take on one of the exalted among his priesthood—the redoubtable Nobel laureate Luis W. Alvarez. Specifically, McLean was about to challenge Alvarez’s well-publicized theory that an asteroid had caused the extinction of the dinosaurs and thousands of other species 65 million years ago. The real angel of death, he would argue, was a “greenhouse effect” caused by intense volcanic activity.
The audience of scientists was looking forward to the talk; most of them were fellow heretics. But before McLean could begin, something started roaring outside the auditorium. The noise grew quickly, and as it reached near-deafening dimensions, McLean ...
