The satire of The Genocides depends in large measure on the familiarity of its situation, characters, and themes.

The novel recalls The Day of the Triffids, which features alien plants ravaging earth and destroying modern civilization. The War of the Worlds sets the basic pattern for alien invasion novels. It has people heroically battling the frightfully deadly war machines of Martians.

Eventually, a small virtue of planet Earth — its microbes — destroys the Martian enemy. Humanity is taken to the brink of destruction only to be saved at the last moment. In some novels, the factor that saves humanity may be a human characteristic such as the power of love or a scientific discovery that pinpoints a fatal weakness in the alien invaders. The Genocides skips the last-moment device that saves humanity and carries its plot to its logical conclusion: the extinction of humanity.