On the Origin of Species and its ability to explain a wide range of observations. The "Examiner" review of 3 December 1859 commented, "Much of Mr. Darwin's volume is what ordinary readers would call 'tough reading;' that is, writing which to comprehend requires concentrated attention and some preparation for the task. All, however, is by no means of this description, and many parts of the book abound in information, easy to comprehend and both instructive and entertaining." While the book was readable enough to sell, its dryness ensured that it was seen as aimed at specialist scientists and could not be dismissed as mere journalism
On the Origin of Species miles wide. His explanation was a combination of migration and descent with modification. He went on to say: "On this principle of inheritance with modification, we can understand how it is that sections of genera, whole genera, and even families are confined to the same areas, as is so commonly and notoriously the case." Darwin explained how a volcanic island formed a few hundred miles from a continent might be colonised by a few species from that continent. These species would become modified over time, but would still be related to species found on the continent, and Darwin observed that