For historians it is obviously important to know when events happened and when those events were recorded and this is where biology is important. A biologist at Penn State as figured out that the way biologists track mutations can be applied to the dating of books. Good news not only for historians, but also for book collectors and librarians.

“The so-called “print clock” technique incorporates some complicated statistical formulas. But professor Blair Hedges says much of his analysis on 16th- and 17th-century books and prints was conducted by simply counting the number of discrepancies such as “line breaks” on the same pages in the different editions of a book. An example of a line break would be a faded line in a drawing that may have been bolder in an earlier edition of a book.”