On the Cutting Edge - Professional Development for Geoscience Faculty
Rates, Dates and Geologic Time: Teaching about the Temporal Aspects of Geoscience
Rates and Time > Activity Posters > How much is a million? How big is a billion?

How much is a million? How big is a billion? Getting a handle on the immensity of geologic time

Danita Brandt, Elizabeth Conover, and Kristen Johnson
,
Michigan State University
Author Profile

Summary

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.

Context

Audience:

general public

Skills and concepts that students must have mastered:

no prior skills necessary; concepts: the Earth has changed through time, we have ways to calibrate that record of change, and we can put events in their proper chronologic order

How the activity is situated in the course:

may be used as stand alone or as follow-on to discussion of the development of the geologic time scale

Goals

Content/concepts goals for this activity:

Immensity of geologic time; the proper chronologic perspective of the eons, eras, and periods of the geologic time scale

Geologic skills:

becoming familiar with the geologic time scale

Higher order thinking skills goals for this activity:

interpreting a two-dimensional representation (charts of geologic time scale) in its proper 4th dimensional aspect (time)

Other skills goals for this activity:

measurement, scaling, unit conversion

Description of the activity/assignment

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 eventsin 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.

Evaluation

To know: whether students develop a more accurate view of events in Earth's deep history relative to more recent events for which we have a more abundant record

pre- and post-activity quizzes

Logistics

no special tools required

Poster Presentation

How much is a million? How big is a billion? Getting a handle on the immensity of geologic time (PowerPoint 498kB Feb15 06)

See more Activity Posters »