A portion of a popular college text in historical geology includes 10 chapters (281 pages) in a unit titled “The Story of Earth.” Two chapters (49 pages) are devoted to Precambrian time. By contrast, the last two chapters (67 pages) focus on the most recent 23 million years, with 25 of those pages devoted to the Holocene Epoch, which began 10,000 years ago.

a. Compare the percentage of pages devoted to the Precambrian to the actual percentage of geologic time that this span represents.

b. How does the number of pages about the Holocene compare to its actual percentage of the geologic time?

c. Suggest some reasons why the text seems to have such an unequal treatment of Earth history.