HOW SHOULD WE BE PRESENTING GEOLOGIC TIME IN MUSEUM EXHIBITS?

Geologic time is an integral and daily part of the work and world view of almost all professional geologists, and one of the central themes of geology and perhaps its greatest contribution to human thought. An understanding of geologic time is also essential for general science literacy. It is thus ironic that geologic time is among the areas of geology most poorly understood by the general public. This is particularly true in otherwise highly popular and successful museum exhibits.

Surveys suggest that a majority of Americans accept that the Earth is old (at least millions of years), but also that they have numerous misconceptions regarding the process of measuring geologic time, as well as the pattern in relative timing of major events in Earth history. Barriers to comprehension of geologic time include: (1) difficulty comprehending large numbers, the impact of long intervals upon slow processes and rare events, and processes occurring over several orders of magnitude; (2) underestimation of the amount of data and independent evidence that support the geologic time scale; (3) lack of distinction between numerical and relative dating; (4) tendency to lump historical events into a single "past"; and (5) inexperience in associating processes and passage of time with static objects and landforms..

Most natural history museums have geologic time exhibits but they vary widely, from inconspicuous (and largely unread) text panels to more ambitious timelines and radiometric dating interactives. Anecdotal evidence suggests that none of these are very popular or effective in communicating what geologists think is important about the subject.

Museum exhibits on geologic time should build on the strength of museums, which is objects and how they can be interpreted to yield insights about natural processes (#5 above). We have experimented with some success with exhibits that start with the “biography” of a rock, and encourage visitors to try to interpret rocks in terms their histories, which is the most important geological insight of all and may have the most practical implications for museum visitors. Combining this approach with providing visitor-friendly access to the abundance of actual biostratigraphic and chronostratigraphic data now widely available on-line might lead to a new generation of museum exhibit experiences.