The Science of Discworld III: Darwin's Watch
 In the Discworld story the wizards learn that, once again, the history of Roundworld has changed, resulting in humans failing to leave Earth before the Extinction Level Event shown in the earlier books. They discover that the difference from established history was that Charles Darwin wrote a book called Theology of Species, which described how evolution must be controlled by a Creator. This was generally accepted by both religious figures and conservative scientists, and led to a certain stagnation of thought, preventing the eventual invention of the space elevator. When the wizards try to correct this, the potential futures of Roundworld go mad. The possibility of Darwin ever writing the book becomes zero, with most futures featuring his death in seemingly improbable ways. The wizards eventually deduce that Roundworld has caught the attention of the Auditors of Reality, who approve of a universe which runs on unthinking rules, and disapprove of humans, who try to make it more like the Discworld. Unlike the elven invasion in The Globe, which suppressed our creativity unthinkingly, this is a deliberate attempt to prevent humans escaping Earth. While attempting to maintain a timeline where The Origin was written, the wizards inadvertently take Darwin to the Discworld. There they discover that his line of thought was disrupted by the Disc's God of Evolution, leading to Theology. After defeating the Auditors the wizards manage to correct this, by explaining the situation to Darwin. Since Darwin then wishes to forget the whole thing, they are ethically able to grant his request.