How much is a million? How big is a billion?
Danita Brandt, Michigan State University
We constructed a geologic timeline along a 5K road-race route across the MSU campus at a scale of 1 meter = 1 million years, using signage to mark important events in the history of life. In addition to over 1500 race participants, numerous casual observers were exposed to the timeline. This project works well in the classroom at a scale of 1 mm = 1 million years, and as a manageable one-day outdoor sidewalk chalk activity at a scale of 1" = 1 million years. Timelines drawn to scale lead the observer to the inescapable conclusions that "simple" life appeared early in Earth history; that it took the bulk of Earth history to achieve the next, multi-cellular stage of development; and that once the metazoan threshold was crossed, subsequent biological diversification-and the resulting fossil record-followed in rapid succession.