Using Google Earth to Teach the Magnitude of Deep Time

Most timeline analogies of geologic and evolutionary time are fundamentally flawed. They trade off the problem of grasping very long times for the problem of grasping very short distances. The result is an understanding of relative time with little comprehension of absolute time. Earlier work has shown that the distances most easily understood by teachers and students are those most people can experience directly. Thus most timeline analogies are flawed by either overcompressing an experienceable time or relying on an unexperienceable distance. Under the constraint of experienceability, the best timeline to distance scale must be at least 75 miles and no more than about 500 miles long. Using Google Earth, one can construct such ideal timeline analogies relative to a point in the classroom with locally adaptable markers for important events in geologic time. I have used these analogies for several years in university and public lectures to great effect. (Contains 1 table and 2 figures.)