FlowingData passes along the link to this fine piece of work by Ben Fry.  “Ben Fry Visualizes the Evolution of Darwin’s Ideas” Journos could be using a similar approach to analyze the evolution of the ideas of public officials.

Ben Fry Visualizes the Evolution of Darwin’s Ideas

“Ben Fry, well-known for Processing and plenty of other data goodness, announced his most recent piece, On the Origin of Species: The Preservation of Favoured Traces, made possible by The Complete Work of Charles Darwin Online.

The visualization explores the evolution of Charles Darwin's theory of, uh, evolution. It began as a less-defined 150,000-word text in the first edition and grew and developed to a 190,000-word theory in the sixth edition.

Watch where the updates in the text occur over time. Chunks are removed, chunks are added, and words are changed. Blocks are color-coded by edition. Roll over blocks to see the text underneath.

As usual, excellent work, Mr. Fry.”